Import zstd 1.3.0vendor/zstd/1.3.0

57 files changed, 5988 insertions, 2468 deletions

diff --git a/Makefile b/Makefile
index 54652665bc76..ac3034c9b7bf 100644
--- a/Makefile
+++ b/Makefile
@@ -108,7 +108,7 @@ clean:
 #------------------------------------------------------------------------------
 # make install is validated only for Linux, OSX, Hurd and some BSD targets
 #------------------------------------------------------------------------------
-ifneq (,$(filter $(shell uname),Linux Darwin GNU/kFreeBSD GNU FreeBSD DragonFly NetBSD))
+ifneq (,$(filter $(shell uname),Linux Darwin GNU/kFreeBSD GNU FreeBSD DragonFly NetBSD MSYS_NT))
 
 HOST_OS = POSIX
 CMAKE_PARAMS = -DZSTD_BUILD_CONTRIB:BOOL=ON -DZSTD_BUILD_STATIC:BOOL=ON -DZSTD_BUILD_TESTS:BOOL=ON -DZSTD_ZLIB_SUPPORT:BOOL=ON -DZSTD_LZMA_SUPPORT:BOOL=ON
@@ -117,30 +117,36 @@ CMAKE_PARAMS = -DZSTD_BUILD_CONTRIB:BOOL=ON -DZSTD_BUILD_STATIC:BOOL=ON -DZSTD_B
 list:
 	@$(MAKE) -pRrq -f $(lastword $(MAKEFILE_LIST)) : 2>/dev/null | awk -v RS= -F: '/^# File/,/^# Finished Make data base/ {if ($$1 !~ "^[#.]") {print $$1}}' | sort | egrep -v -e '^[^[:alnum:]]' -e '^$@$$' | xargs
 
-.PHONY: install uninstall travis-install clangtest gpptest armtest usan asan uasan
+.PHONY: install clangtest gpptest armtest usan asan uasan
 install:
 	@$(MAKE) -C $(ZSTDDIR) $@
 	@$(MAKE) -C $(PRGDIR) $@
 
+.PHONY: uninstall
 uninstall:
 	@$(MAKE) -C $(ZSTDDIR) $@
 	@$(MAKE) -C $(PRGDIR) $@
 
+.PHONY: travis-install
 travis-install:
 	$(MAKE) install PREFIX=~/install_test_dir
 
+.PHONY: gppbuild
 gppbuild: clean
 	g++ -v
 	CC=g++ $(MAKE) -C programs all CFLAGS="-O3 -Wall -Wextra -Wundef -Wshadow -Wcast-align -Werror"
 
+.PHONY: gcc5build
 gcc5build: clean
 	gcc-5 -v
 	CC=gcc-5 $(MAKE) all MOREFLAGS="-Werror"
 
+.PHONY: gcc6build
 gcc6build: clean
 	gcc-6 -v
 	CC=gcc-6 $(MAKE) all MOREFLAGS="-Werror"
 
+.PHONY: clangbuild
 clangbuild: clean
 	clang -v
 	CXX=clang++ CC=clang $(MAKE) all MOREFLAGS="-Werror -Wconversion -Wno-sign-conversion -Wdocumentation"
@@ -224,10 +230,10 @@ asan-%: clean
 	LDFLAGS=-fuse-ld=gold MOREFLAGS="-g -fno-sanitize-recover=all -fsanitize=address" $(MAKE) -C $(TESTDIR) $*
 
 msan: clean
-	$(MAKE) test CC=clang MOREFLAGS="-g -fsanitize=memory -fno-omit-frame-pointer"   # datagen.c fails this test for no obvious reason
+	$(MAKE) test CC=clang MOREFLAGS="-g -fsanitize=memory -fno-omit-frame-pointer" HAVE_LZMA=0   # datagen.c fails this test for no obvious reason
 
 msan-%: clean
-	LDFLAGS=-fuse-ld=gold MOREFLAGS="-fno-sanitize-recover=all -fsanitize=memory -fno-omit-frame-pointer" $(MAKE) -C $(TESTDIR) $*
+	LDFLAGS=-fuse-ld=gold MOREFLAGS="-g -fno-sanitize-recover=all -fsanitize=memory -fno-omit-frame-pointer" FUZZER_FLAGS=--no-big-tests $(MAKE) -C $(TESTDIR) HAVE_LZMA=0 $*
 
 asan32: clean
 	$(MAKE) -C $(TESTDIR) test32 CC=clang MOREFLAGS="-g -fsanitize=address"
@@ -236,10 +242,11 @@ uasan: clean
 	$(MAKE) test CC=clang MOREFLAGS="-g -fno-sanitize-recover=all -fsanitize-recover=signed-integer-overflow -fsanitize=address,undefined"
 
 uasan-%: clean
-	LDFLAGS=-fuse-ld=gold MOREFLAGS="-Og -fno-sanitize-recover=all -fsanitize-recover=signed-integer-overflow -fsanitize=address,undefined" $(MAKE) -C $(TESTDIR) $*
+	LDFLAGS=-fuse-ld=gold MOREFLAGS="-g -fno-sanitize-recover=all -fsanitize-recover=signed-integer-overflow -fsanitize=address,undefined" $(MAKE) -C $(TESTDIR) $*
 
 tsan-%: clean
-	LDFLAGS=-fuse-ld=gold MOREFLAGS="-g -fno-sanitize-recover=all -fsanitize=thread" $(MAKE) -C $(TESTDIR) $*
+	LDFLAGS=-fuse-ld=gold MOREFLAGS="-g -fno-sanitize-recover=all -fsanitize=thread" $(MAKE) -C $(TESTDIR) $* FUZZER_FLAGS=--no-big-tests
+
 apt-install:
 	sudo apt-get -yq --no-install-suggests --no-install-recommends --force-yes install $(APT_PACKAGES)
 
diff --git a/NEWS b/NEWS
index 7d9c9c94e186..d23a58f02046 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,18 @@
+v1.3.0
+cli : new : `--list` command, by Paul Cruz
+cli : changed : xz/lzma support enabled by default
+cli : changed : `-t *` continue processing list after a decompression error
+API : added : ZSTD_versionString()
+API : promoted to stable status : ZSTD_getFrameContentSize(), by Sean Purcell
+API exp : new advanced API : ZSTD_compress_generic(), ZSTD_CCtx_setParameter()
+API exp : new : API for static or external allocation : ZSTD_initStatic?Ctx()
+API exp : added : ZSTD_decompressBegin_usingDDict(), requested by Guy Riddle (#700)
+API exp : clarified memory estimation / measurement functions.
+API exp : changed : strongest strategy renamed ZSTD_btultra, fastest strategy ZSTD_fast set to 1
+tools : decodecorpus can generate random dictionary-compressed samples, by Paul Cruz
+new : contrib/seekable_format, demo and API, by Sean Purcell
+changed : contrib/linux-kernel, updated version and license, by Nick Terrell
+
 v1.2.0
 cli : changed : Multithreading enabled by default (use target zstd-nomt or HAVE_THREAD=0 to disable)
 cli : new : command -T0 means "detect and use nb of cores", by Sean Purcell
diff --git a/README.md b/README.md
index 7caee5fd3f67..f37be4542c69 100644
--- a/README.md
+++ b/README.md
@@ -6,10 +6,17 @@ and a command line utility producing and decoding `.zst` and `.gz` files.
 For other programming languages,
 you can consult a list of known ports on [Zstandard homepage](http://www.zstd.net/#other-languages).
 
-|Branch      |Status   |
-|------------|---------|
-|master      | [![Build Status](https://travis-ci.org/facebook/zstd.svg?branch=master)](https://travis-ci.org/facebook/zstd) |
-|dev         | [![Build Status](https://travis-ci.org/facebook/zstd.svg?branch=dev)](https://travis-ci.org/facebook/zstd) |
+| dev branch status |
+|-------------------|
+| [![Build Status][travisDevBadge]][travisLink]   [![Build status][AppveyorDevBadge]][AppveyorLink]   [![Build status][CircleDevBadge]][CircleLink]
+
+[travisDevBadge]: https://travis-ci.org/facebook/zstd.svg?branch=dev "Continuous Integration test suite"
+[travisLink]: https://travis-ci.org/facebook/zstd
+[AppveyorDevBadge]: https://ci.appveyor.com/api/projects/status/xt38wbdxjk5mrbem/branch/dev?svg=true "Windows test suite"
+[AppveyorLink]: https://ci.appveyor.com/project/YannCollet/zstd-p0yf0
+[CircleDevBadge]: https://circleci.com/gh/facebook/zstd/tree/dev.svg?style=shield "Short test suite"
+[CircleLink]: https://circleci.com/gh/facebook/zstd
+
 
 As a reference, several fast compression algorithms were tested and compared
 on a server running Linux Debian (`Linux version 4.8.0-1-amd64`),
@@ -60,11 +67,11 @@ Previous charts provide results applicable to typical file and stream scenarios
 The smaller the amount of data to compress, the more difficult it is to compress. This problem is common to all compression algorithms, and reason is, compression algorithms learn from past data how to compress future data. But at the beginning of a new data set, there is no "past" to build upon.
 
 To solve this situation, Zstd offers a __training mode__, which can be used to tune the algorithm for a selected type of data.
-Training Zstandard is achieved by provide it with a few samples (one file per sample). The result of this training is stored in a file called "dictionary", which must be loaded before compression and decompression.
+Training Zstandard is achieved by providing it with a few samples (one file per sample). The result of this training is stored in a file called "dictionary", which must be loaded before compression and decompression.
 Using this dictionary, the compression ratio achievable on small data improves dramatically.
 
 The following example uses the `github-users` [sample set](https://github.com/facebook/zstd/releases/tag/v1.1.3), created from [github public API](https://developer.github.com/v3/users/#get-all-users).
-It consists of roughly 10K records weighting about 1KB each.
+It consists of roughly 10K records weighing about 1KB each.
 
 Compression Ratio | Compression Speed | Decompression Speed
 ------------------|-------------------|--------------------
diff --git a/appveyor.yml b/appveyor.yml
index 67c4f72d7995..1815563e7f5d 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -30,12 +30,6 @@
       SCRIPT:   ""
       TEST:     "cmake"
 
-    - COMPILER: "gcc"
-      HOST:     "mingw"
-      PLATFORM: "x64"
-      SCRIPT:   ""
-      TEST:     "pzstd"
-
     - COMPILER: "visual"
       HOST:     "visual"
       PLATFORM: "x64"
@@ -88,12 +82,10 @@
       ( if [%COMPILER%]==[gcc] if [%ARTIFACT%]==[true]
           lib\dll\example\build_package.bat &&
           make -C programs DEBUGFLAGS= clean zstd &&
-          cp programs\zstd.exe zstd_%PLATFORM%.exe &&
-          appveyor PushArtifact zstd_%PLATFORM%.exe &&
-          cp programs\zstd.exe bin\zstd.exe &&
-          make -C programs DEBUGFLAGS= clean zstdmt &&
-          cp programs\zstd.exe bin\zstdmt.exe &&
-          cd bin\ && 7z a -tzip zstd-win-release-%PLATFORM%.zip * &&
+          cd programs\ && 7z a -tzip -mx9 zstd-win-binary-%PLATFORM%.zip zstd.exe &&
+          appveyor PushArtifact zstd-win-binary-%PLATFORM%.zip &&
+          cp zstd.exe ..\bin\zstd.exe &&
+          cd ..\bin\ && 7z a -tzip -mx9 zstd-win-release-%PLATFORM%.zip * &&
           appveyor PushArtifact zstd-win-release-%PLATFORM%.zip
       )
     )
@@ -159,13 +151,6 @@
       cd ..\..\.. &&
       make clean
     )
-  - if [%TEST%]==[pzstd] (
-      make -C contrib\pzstd googletest-mingw64 &&
-      make -C contrib\pzstd pzstd.exe &&
-      make -C contrib\pzstd tests &&
-      make -C contrib\pzstd check &&
-      make -C contrib\pzstd clean
-    )
   - SET "FUZZERTEST=-T30s"
   - if [%HOST%]==[visual] if [%CONFIGURATION%]==[Release] (
       CD tests &&
diff --git a/contrib/pzstd/Pzstd.cpp b/contrib/pzstd/Pzstd.cpp
index 1265b53efc0b..ae5d73444413 100644
--- a/contrib/pzstd/Pzstd.cpp
+++ b/contrib/pzstd/Pzstd.cpp
@@ -585,7 +585,10 @@ std::uint64_t writeFile(
   std::uint64_t bytesWritten = 0;
   std::shared_ptr<BufferWorkQueue> out;
   // Grab the output queue for each decompression job (in order).
-  while (outs.pop(out) && !errorHolder.hasError()) {
+  while (outs.pop(out)) {
+    if (errorHolder.hasError()) {
+      continue;
+    }
     if (!decompress) {
       // If we are compressing and want to write skippable frames we can't
       // start writing before compression is done because we need to know the
diff --git a/doc/zstd_manual.html b/doc/zstd_manual.html
index 2e77e7742f60..cd2b06dd8309 100644
--- a/doc/zstd_manual.html
+++ b/doc/zstd_manual.html
@@ -1,10 +1,10 @@
 <html>
 <head>
 <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
-<title>zstd 1.2.0 Manual</title>
+<title>zstd 1.3.0 Manual</title>
 </head>
 <body>
-<h1>zstd 1.2.0 Manual</h1>
+<h1>zstd 1.3.0 Manual</h1>
 <hr>
 <a name="Contents"></a><h2>Contents</h2>
 <ol>
@@ -13,14 +13,14 @@
 <li><a href="#Chapter3">Simple API</a></li>
 <li><a href="#Chapter4">Explicit memory management</a></li>
 <li><a href="#Chapter5">Simple dictionary API</a></li>
-<li><a href="#Chapter6">Fast dictionary API</a></li>
+<li><a href="#Chapter6">Bulk processing dictionary API</a></li>
 <li><a href="#Chapter7">Streaming</a></li>
 <li><a href="#Chapter8">Streaming compression - HowTo</a></li>
 <li><a href="#Chapter9">Streaming decompression - HowTo</a></li>
 <li><a href="#Chapter10">START OF ADVANCED AND EXPERIMENTAL FUNCTIONS</a></li>
 <li><a href="#Chapter11">Advanced types</a></li>
-<li><a href="#Chapter12">Compressed size functions</a></li>
-<li><a href="#Chapter13">Decompressed size functions</a></li>
+<li><a href="#Chapter12">Frame size functions</a></li>
+<li><a href="#Chapter13">Context memory usage</a></li>
 <li><a href="#Chapter14">Advanced compression functions</a></li>
 <li><a href="#Chapter15">Advanced decompression functions</a></li>
 <li><a href="#Chapter16">Advanced streaming functions</a></li>
@@ -31,26 +31,27 @@
 </ol>
 <hr>
 <a name="Chapter1"></a><h2>Introduction</h2><pre>
-  zstd, short for Zstandard, is a fast lossless compression algorithm, targeting real-time compression scenarios
-  at zlib-level and better compression ratios. The zstd compression library provides in-memory compression and
-  decompression functions. The library supports compression levels from 1 up to ZSTD_maxCLevel() which is 22.
+  zstd, short for Zstandard, is a fast lossless compression algorithm,
+  targeting real-time compression scenarios at zlib-level and better compression ratios.
+  The zstd compression library provides in-memory compression and decompression functions.
+  The library supports compression levels from 1 up to ZSTD_maxCLevel() which is currently 22.
   Levels >= 20, labeled `--ultra`, should be used with caution, as they require more memory.
   Compression can be done in:
     - a single step (described as Simple API)
     - a single step, reusing a context (described as Explicit memory management)
     - unbounded multiple steps (described as Streaming compression)
-  The compression ratio achievable on small data can be highly improved using compression with a dictionary in:
+  The compression ratio achievable on small data can be highly improved using a dictionary in:
     - a single step (described as Simple dictionary API)
     - a single step, reusing a dictionary (described as Fast dictionary API)
 
   Advanced experimental functions can be accessed using #define ZSTD_STATIC_LINKING_ONLY before including zstd.h.
-  These APIs shall never be used with a dynamic library.
+  Advanced experimental APIs shall never be used with a dynamic library.
   They are not "stable", their definition may change in the future. Only static linking is allowed.
 <BR></pre>
 
 <a name="Chapter2"></a><h2>Version</h2><pre></pre>
 
-<pre><b>unsigned ZSTD_versionNumber(void);   </b>/**< library version number; to be used when checking dll version */<b>
+<pre><b>unsigned ZSTD_versionNumber(void);   </b>/**< useful to check dll version */<b>
 </b></pre><BR>
 <a name="Chapter3"></a><h2>Simple API</h2><pre></pre>
 
@@ -66,28 +67,24 @@
 <pre><b>size_t ZSTD_decompress( void* dst, size_t dstCapacity,
                   const void* src, size_t compressedSize);
 </b><p>  `compressedSize` : must be the _exact_ size of some number of compressed and/or skippable frames.
-  `dstCapacity` is an upper bound of originalSize.
+  `dstCapacity` is an upper bound of originalSize to regenerate.
   If user cannot imply a maximum upper bound, it's better to use streaming mode to decompress data.
   @return : the number of bytes decompressed into `dst` (<= `dstCapacity`),
             or an errorCode if it fails (which can be tested using ZSTD_isError()). 
 </p></pre><BR>
 
 <pre><b>unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize);
-</b><p>  NOTE: This function is planned to be obsolete, in favour of ZSTD_getFrameContentSize.
-  ZSTD_getFrameContentSize functions the same way, returning the decompressed size of a single
-  frame, but distinguishes empty frames from frames with an unknown size, or errors.
-
-  Additionally, ZSTD_findDecompressedSize can be used instead.  It can handle multiple
-  concatenated frames in one buffer, and so is more general.
-  As a result however, it requires more computation and entire frames to be passed to it,
-  as opposed to ZSTD_getFrameContentSize which requires only a single frame's header.
+</b><p>  NOTE: This function is planned to be obsolete, in favor of ZSTD_getFrameContentSize().
+  ZSTD_getFrameContentSize() works the same way,
+  returning the decompressed size of a single frame,
+  but distinguishes empty frames from frames with an unknown size, or errors.
 
   'src' is the start of a zstd compressed frame.
   @return : content size to be decompressed, as a 64-bits value _if known_, 0 otherwise.
-   note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
+   note 1 : decompressed size is an optional field, it may not be present, typically in streaming mode.
             When `return==0`, data to decompress could be any size.
             In which case, it's necessary to use streaming mode to decompress data.
-            Optionally, application can still use ZSTD_decompress() while relying on implied limits.
+            Optionally, application can use ZSTD_decompress() while relying on implied limits.
             (For example, data may be necessarily cut into blocks <= 16 KB).
    note 2 : decompressed size is always present when compression is done with ZSTD_compress()
    note 3 : decompressed size can be very large (64-bits value),
@@ -96,7 +93,7 @@
    note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
             Always ensure result fits within application's authorized limits.
             Each application can set its own limits.
-   note 5 : when `return==0`, if precise failure cause is needed, use ZSTD_getFrameParams() to know more. 
+   note 5 : when `return==0`, if precise failure cause is needed, use ZSTD_getFrameHeader() to know more. 
 </p></pre><BR>
 
 <h3>Helper functions</h3><pre></pre><b><pre>int         ZSTD_maxCLevel(void);               </b>/*!< maximum compression level available */<b>
@@ -114,20 +111,26 @@ const char* ZSTD_getErrorName(size_t code);     </b>/*!< provides readable strin
 ZSTD_CCtx* ZSTD_createCCtx(void);
 size_t     ZSTD_freeCCtx(ZSTD_CCtx* cctx);
 </pre></b><BR>
-<pre><b>size_t ZSTD_compressCCtx(ZSTD_CCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize, int compressionLevel);
+<pre><b>size_t ZSTD_compressCCtx(ZSTD_CCtx* ctx,
+                         void* dst, size_t dstCapacity,
+                   const void* src, size_t srcSize,
+                         int compressionLevel);
 </b><p>  Same as ZSTD_compress(), requires an allocated ZSTD_CCtx (see ZSTD_createCCtx()). 
 </p></pre><BR>
 
 <h3>Decompression context</h3><pre>  When decompressing many times,
-  it is recommended to allocate a context just once, and re-use it for each successive compression operation.
+  it is recommended to allocate a context only once,
+  and re-use it for each successive compression operation.
   This will make workload friendlier for system's memory.
-  Use one context per thread for parallel execution in multi-threaded environments. 
+  Use one context per thread for parallel execution. 
 </pre><b><pre>typedef struct ZSTD_DCtx_s ZSTD_DCtx;
 ZSTD_DCtx* ZSTD_createDCtx(void);
 size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);
 </pre></b><BR>
-<pre><b>size_t ZSTD_decompressDCtx(ZSTD_DCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
-</b><p>  Same as ZSTD_decompress(), requires an allocated ZSTD_DCtx (see ZSTD_createDCtx()). 
+<pre><b>size_t ZSTD_decompressDCtx(ZSTD_DCtx* ctx,
+                           void* dst, size_t dstCapacity,
+                     const void* src, size_t srcSize);
+</b><p>  Same as ZSTD_decompress(), requires an allocated ZSTD_DCtx (see ZSTD_createDCtx()) 
 </p></pre><BR>
 
 <a name="Chapter5"></a><h2>Simple dictionary API</h2><pre></pre>
@@ -137,32 +140,33 @@ size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);
                          const void* src, size_t srcSize,
                          const void* dict,size_t dictSize,
                                int compressionLevel);
-</b><p>   Compression using a predefined Dictionary (see dictBuilder/zdict.h).
-   Note : This function loads the dictionary, resulting in significant startup delay.
-   Note : When `dict == NULL || dictSize < 8` no dictionary is used. 
+</b><p>  Compression using a predefined Dictionary (see dictBuilder/zdict.h).
+  Note : This function loads the dictionary, resulting in significant startup delay.
+  Note : When `dict == NULL || dictSize < 8` no dictionary is used. 
 </p></pre><BR>
 
 <pre><b>size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
                                  void* dst, size_t dstCapacity,
                            const void* src, size_t srcSize,
                            const void* dict,size_t dictSize);
-</b><p>   Decompression using a predefined Dictionary (see dictBuilder/zdict.h).
-   Dictionary must be identical to the one used during compression.
-   Note : This function loads the dictionary, resulting in significant startup delay.
-   Note : When `dict == NULL || dictSize < 8` no dictionary is used. 
+</b><p>  Decompression using a predefined Dictionary (see dictBuilder/zdict.h).
+  Dictionary must be identical to the one used during compression.
+  Note : This function loads the dictionary, resulting in significant startup delay.
+  Note : When `dict == NULL || dictSize < 8` no dictionary is used. 
 </p></pre><BR>
 
-<a name="Chapter6"></a><h2>Fast dictionary API</h2><pre></pre>
+<a name="Chapter6"></a><h2>Bulk processing dictionary API</h2><pre></pre>
 
-<pre><b>ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize, int compressionLevel);
-</b><p>   When compressing multiple messages / blocks with the same dictionary, it's recommended to load it just once.
-   ZSTD_createCDict() will create a digested dictionary, ready to start future compression operations without startup delay.
-   ZSTD_CDict can be created once and used by multiple threads concurrently, as its usage is read-only.
-   `dictBuffer` can be released after ZSTD_CDict creation, as its content is copied within CDict 
+<pre><b>ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize,
+                             int compressionLevel);
+</b><p>  When compressing multiple messages / blocks with the same dictionary, it's recommended to load it just once.
+  ZSTD_createCDict() will create a digested dictionary, ready to start future compression operations without startup delay.
+  ZSTD_CDict can be created once and shared by multiple threads concurrently, since its usage is read-only.
+  `dictBuffer` can be released after ZSTD_CDict creation, since its content is copied within CDict 
 </p></pre><BR>
 
 <pre><b>size_t      ZSTD_freeCDict(ZSTD_CDict* CDict);
-</b><p>   Function frees memory allocated by ZSTD_createCDict(). 
+</b><p>  Function frees memory allocated by ZSTD_createCDict(). 
 </p></pre><BR>
 
 <pre><b>size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
@@ -176,20 +180,20 @@ size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);
 </p></pre><BR>
 
 <pre><b>ZSTD_DDict* ZSTD_createDDict(const void* dictBuffer, size_t dictSize);
-</b><p>   Create a digested dictionary, ready to start decompression operation without startup delay.
-   dictBuffer can be released after DDict creation, as its content is copied inside DDict 
+</b><p>  Create a digested dictionary, ready to start decompression operation without startup delay.
+  dictBuffer can be released after DDict creation, as its content is copied inside DDict 
 </p></pre><BR>
 
 <pre><b>size_t      ZSTD_freeDDict(ZSTD_DDict* ddict);
-</b><p>   Function frees memory allocated with ZSTD_createDDict() 
+</b><p>  Function frees memory allocated with ZSTD_createDDict() 
 </p></pre><BR>
 
 <pre><b>size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
                                   void* dst, size_t dstCapacity,
                             const void* src, size_t srcSize,
                             const ZSTD_DDict* ddict);
-</b><p>   Decompression using a digested Dictionary.
-   Faster startup than ZSTD_decompress_usingDict(), recommended when same dictionary is used multiple times. 
+</b><p>  Decompression using a digested Dictionary.
+  Faster startup than ZSTD_decompress_usingDict(), recommended when same dictionary is used multiple times. 
 </p></pre><BR>
 
 <a name="Chapter7"></a><h2>Streaming</h2><pre></pre>
@@ -236,14 +240,18 @@ size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);
   ZSTD_endStream() instructs to finish a frame.
   It will perform a flush and write frame epilogue.
   The epilogue is required for decoders to consider a frame completed.
-  Similar to ZSTD_flushStream(), it may not be able to flush the full content if `output->size` is too small.
+  ZSTD_endStream() may not be able to flush full data if `output->size` is too small.
   In which case, call again ZSTD_endStream() to complete the flush.
-  @return : nb of bytes still present within internal buffer (0 if it's empty, hence compression completed)
+  @return : 0 if frame fully completed and fully flushed,
+             or >0 if some data is still present within internal buffer
+                  (value is minimum size estimation for remaining data to flush, but it could be more)
             or an error code, which can be tested using ZSTD_isError().
 
  
 <BR></pre>
 
+<pre><b>typedef ZSTD_CCtx ZSTD_CStream;  </b>/**< CCtx and CStream are now effectively same object (>= v1.3.0) */<b>
+</b></pre><BR>
 <h3>ZSTD_CStream management functions</h3><pre></pre><b><pre>ZSTD_CStream* ZSTD_createCStream(void);
 size_t ZSTD_freeCStream(ZSTD_CStream* zcs);
 </pre></b><BR>
@@ -277,6 +285,8 @@ size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output);
  
 <BR></pre>
 
+<pre><b>typedef ZSTD_DCtx ZSTD_DStream;  </b>/**< DCtx and DStream are now effectively same object (>= v1.3.0) */<b>
+</b></pre><BR>
 <h3>ZSTD_DStream management functions</h3><pre></pre><b><pre>ZSTD_DStream* ZSTD_createDStream(void);
 size_t ZSTD_freeDStream(ZSTD_DStream* zds);
 </pre></b><BR>
@@ -296,7 +306,8 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
 
 <a name="Chapter11"></a><h2>Advanced types</h2><pre></pre>
 
-<pre><b>typedef enum { ZSTD_fast, ZSTD_dfast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2, ZSTD_btlazy2, ZSTD_btopt, ZSTD_btopt2 } ZSTD_strategy;   </b>/* from faster to stronger */<b>
+<pre><b>typedef enum { ZSTD_fast=1, ZSTD_dfast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2,
+               ZSTD_btlazy2, ZSTD_btopt, ZSTD_btultra } ZSTD_strategy;   </b>/* from faster to stronger */<b>
 </b></pre><BR>
 <pre><b>typedef struct {
     unsigned windowLog;      </b>/**< largest match distance : larger == more compression, more memory needed during decompression */<b>
@@ -319,68 +330,141 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
     ZSTD_frameParameters fParams;
 } ZSTD_parameters;
 </b></pre><BR>
+<pre><b>typedef struct {
+    unsigned long long frameContentSize;
+    size_t windowSize;
+    unsigned dictID;
+    unsigned checksumFlag;
+} ZSTD_frameHeader;
+</b></pre><BR>
 <h3>Custom memory allocation functions</h3><pre></pre><b><pre>typedef void* (*ZSTD_allocFunction) (void* opaque, size_t size);
 typedef void  (*ZSTD_freeFunction) (void* opaque, void* address);
 typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; void* opaque; } ZSTD_customMem;
+</b>/* use this constant to defer to stdlib's functions */<b>
+static const ZSTD_customMem ZSTD_defaultCMem = { NULL, NULL, NULL };
 </pre></b><BR>
-<a name="Chapter12"></a><h2>Compressed size functions</h2><pre></pre>
+<a name="Chapter12"></a><h2>Frame size functions</h2><pre></pre>
 
 <pre><b>size_t ZSTD_findFrameCompressedSize(const void* src, size_t srcSize);
 </b><p>  `src` should point to the start of a ZSTD encoded frame or skippable frame
   `srcSize` must be at least as large as the frame
-  @return : the compressed size of the frame pointed to by `src`, suitable to pass to
-      `ZSTD_decompress` or similar, or an error code if given invalid input. 
+  @return : the compressed size of the frame pointed to by `src`,
+            suitable to pass to `ZSTD_decompress` or similar,
+            or an error code if given invalid input. 
 </p></pre><BR>
 
-<a name="Chapter13"></a><h2>Decompressed size functions</h2><pre></pre>
-
-<pre><b>unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
-</b><p>   `src` should point to the start of a ZSTD encoded frame
-   `srcSize` must be at least as large as the frame header.  A value greater than or equal
-       to `ZSTD_frameHeaderSize_max` is guaranteed to be large enough in all cases.
-   @return : decompressed size of the frame pointed to be `src` if known, otherwise
-             - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined
-             - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) 
+<pre><b>#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1)
+#define ZSTD_CONTENTSIZE_ERROR   (0ULL - 2)
+unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
+</b><p>  `src` should point to the start of a ZSTD encoded frame.
+  `srcSize` must be at least as large as the frame header.
+       A value >= `ZSTD_frameHeaderSize_max` is guaranteed to be large enough.
+  @return : - decompressed size of the frame pointed to be `src` if known
+            - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined
+            - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) 
 </p></pre><BR>
 
 <pre><b>unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);
-</b><p>   `src` should point the start of a series of ZSTD encoded and/or skippable frames
-   `srcSize` must be the _exact_ size of this series
+</b><p>  `src` should point the start of a series of ZSTD encoded and/or skippable frames
+  `srcSize` must be the _exact_ size of this series
        (i.e. there should be a frame boundary exactly `srcSize` bytes after `src`)
-   @return : the decompressed size of all data in the contained frames, as a 64-bit value _if known_
-             - if the decompressed size cannot be determined: ZSTD_CONTENTSIZE_UNKNOWN
-             - if an error occurred: ZSTD_CONTENTSIZE_ERROR
-
-    note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
-             When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size.
-             In which case, it's necessary to use streaming mode to decompress data.
-             Optionally, application can still use ZSTD_decompress() while relying on implied limits.
-             (For example, data may be necessarily cut into blocks <= 16 KB).
-    note 2 : decompressed size is always present when compression is done with ZSTD_compress()
-    note 3 : decompressed size can be very large (64-bits value),
-             potentially larger than what local system can handle as a single memory segment.
-             In which case, it's necessary to use streaming mode to decompress data.
-    note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
-             Always ensure result fits within application's authorized limits.
-             Each application can set its own limits.
-    note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to
-             read each contained frame header.  This is efficient as most of the data is skipped,
-             however it does mean that all frame data must be present and valid. 
+  @return : - decompressed size of all data in all successive frames
+            - if the decompressed size cannot be determined: ZSTD_CONTENTSIZE_UNKNOWN
+            - if an error occurred: ZSTD_CONTENTSIZE_ERROR
+
+   note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
+            When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size.
+            In which case, it's necessary to use streaming mode to decompress data.
+            Optionally, application can still use ZSTD_decompress() while relying on implied limits.
+            (For example, data may be necessarily cut into blocks <= 16 KB).
+   note 2 : decompressed size is always present when compression is done with ZSTD_compress()
+   note 3 : decompressed size can be very large (64-bits value),
+            potentially larger than what local system can handle as a single memory segment.
+            In which case, it's necessary to use streaming mode to decompress data.
+   note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
+            Always ensure result fits within application's authorized limits.
+            Each application can set its own limits.
+   note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to
+            read each contained frame header.  This is efficient as most of the data is skipped,
+            however it does mean that all frame data must be present and valid. 
 </p></pre><BR>
 
-<a name="Chapter14"></a><h2>Advanced compression functions</h2><pre></pre>
+<pre><b>size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize);
+</b><p>   `src` should point to the start of a ZSTD frame
+   `srcSize` must be >= ZSTD_frameHeaderSize_prefix.
+   @return : size of the Frame Header 
+</p></pre><BR>
+
+<a name="Chapter13"></a><h2>Context memory usage</h2><pre></pre>
 
-<pre><b>size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams);
-</b><p>  Gives the amount of memory allocated for a ZSTD_CCtx given a set of compression parameters.
-  `frameContentSize` is an optional parameter, provide `0` if unknown 
+<pre><b>size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
+size_t ZSTD_sizeof_DCtx(const ZSTD_DCtx* dctx);
+size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs);
+size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds);
+size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict);
+size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
+</b><p>  These functions give the current memory usage of selected object.
+  Object memory usage can evolve if it's re-used multiple times. 
+</p></pre><BR>
+
+<pre><b>size_t ZSTD_estimateCCtxSize(int compressionLevel);
+size_t ZSTD_estimateCCtxSize_advanced(ZSTD_compressionParameters cParams);
+size_t ZSTD_estimateDCtxSize(void);
+</b><p>  These functions make it possible to estimate memory usage
+  of a future {D,C}Ctx, before its creation.
+  ZSTD_estimateCCtxSize() will provide a budget large enough for any compression level up to selected one.
+  It will also consider src size to be arbitrarily "large", which is worst case.
+  If srcSize is known to always be small, ZSTD_estimateCCtxSize_advanced() can provide a tighter estimation.
+  ZSTD_estimateCCtxSize_advanced() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel.
+  Note : CCtx estimation is only correct for single-threaded compression 
+</p></pre><BR>
+
+<pre><b>size_t ZSTD_estimateCStreamSize(int compressionLevel);
+size_t ZSTD_estimateCStreamSize_advanced(ZSTD_compressionParameters cParams);
+size_t ZSTD_estimateDStreamSize(size_t windowSize);
+size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize);
+</b><p>  ZSTD_estimateCStreamSize() will provide a budget large enough for any compression level up to selected one.
+  It will also consider src size to be arbitrarily "large", which is worst case.
+  If srcSize is known to always be small, ZSTD_estimateCStreamSize_advanced() can provide a tighter estimation.
+  ZSTD_estimateCStreamSize_advanced() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel.
+  Note : CStream estimation is only correct for single-threaded compression.
+  ZSTD_DStream memory budget depends on window Size.
+  This information can be passed manually, using ZSTD_estimateDStreamSize,
+  or deducted from a valid frame Header, using ZSTD_estimateDStreamSize_fromFrame();
+  Note : if streaming is init with function ZSTD_init?Stream_usingDict(),
+         an internal ?Dict will be created, which additional size is not estimated here.
+         In this case, get total size by adding ZSTD_estimate?DictSize 
+</p></pre><BR>
+
+<pre><b>size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel);
+size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, unsigned byReference);
+size_t ZSTD_estimateDDictSize(size_t dictSize, unsigned byReference);
+</b><p>  ZSTD_estimateCDictSize() will bet that src size is relatively "small", and content is copied, like ZSTD_createCDict().
+  ZSTD_estimateCStreamSize_advanced() makes it possible to control precisely compression parameters, like ZSTD_createCDict_advanced().
+  Note : dictionary created "byReference" are smaller 
 </p></pre><BR>
 
+<a name="Chapter14"></a><h2>Advanced compression functions</h2><pre></pre>
+
 <pre><b>ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem);
 </b><p>  Create a ZSTD compression context using external alloc and free functions 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
-</b><p>  Gives the amount of memory used by a given ZSTD_CCtx 
+<pre><b>ZSTD_CCtx* ZSTD_initStaticCCtx(void* workspace, size_t workspaceSize);
+</b><p>  workspace: The memory area to emplace the context into.
+             Provided pointer must 8-bytes aligned.
+             It must outlive context usage.
+  workspaceSize: Use ZSTD_estimateCCtxSize() or ZSTD_estimateCStreamSize()
+                 to determine how large workspace must be to support scenario.
+ @return : pointer to ZSTD_CCtx*, or NULL if error (size too small)
+  Note : zstd will never resize nor malloc() when using a static cctx.
+         If it needs more memory than available, it will simply error out.
+  Note 2 : there is no corresponding "free" function.
+           Since workspace was allocated externally, it must be freed externally too.
+  Limitation 1 : currently not compatible with internal CDict creation, such as
+                 ZSTD_CCtx_loadDictionary() or ZSTD_initCStream_usingDict().
+  Limitation 2 : currently not compatible with multi-threading
+ 
 </p></pre><BR>
 
 <pre><b>typedef enum {
@@ -399,13 +483,34 @@ typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; v
   It is important that dictBuffer outlives CDict, it must remain read accessible throughout the lifetime of CDict 
 </p></pre><BR>
 
-<pre><b>ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize, unsigned byReference,
+<pre><b>typedef enum { ZSTD_dm_auto=0,        </b>/* dictionary is "full" if it starts with ZSTD_MAGIC_DICTIONARY, rawContent otherwize */<b>
+               ZSTD_dm_rawContent,    </b>/* ensures dictionary is always loaded as rawContent, even if it starts with ZSTD_MAGIC_DICTIONARY */<b>
+               ZSTD_dm_fullDict       </b>/* refuses to load a dictionary if it does not respect Zstandard's specification */<b>
+} ZSTD_dictMode_e;
+</b></pre><BR>
+<pre><b>ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize,
+                                      unsigned byReference, ZSTD_dictMode_e dictMode,
                                       ZSTD_compressionParameters cParams, ZSTD_customMem customMem);
 </b><p>  Create a ZSTD_CDict using external alloc and free, and customized compression parameters 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict);
-</b><p>  Gives the amount of memory used by a given ZSTD_sizeof_CDict 
+<pre><b>ZSTD_CDict* ZSTD_initStaticCDict(
+                void* workspace, size_t workspaceSize,
+          const void* dict, size_t dictSize,
+                unsigned byReference, ZSTD_dictMode_e dictMode,
+                ZSTD_compressionParameters cParams);
+</b><p>  Generate a digested dictionary in provided memory area.
+  workspace: The memory area to emplace the dictionary into.
+             Provided pointer must 8-bytes aligned.
+             It must outlive dictionary usage.
+  workspaceSize: Use ZSTD_estimateCDictSize()
+                 to determine how large workspace must be.
+  cParams : use ZSTD_getCParams() to transform a compression level
+            into its relevants cParams.
+ @return : pointer to ZSTD_CDict*, or NULL if error (size too small)
+  Note : there is no corresponding "free" function.
+         Since workspace was allocated externally, it must be freed externally.
+ 
 </p></pre><BR>
 
 <pre><b>ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long estimatedSrcSize, size_t dictSize);
@@ -423,8 +528,8 @@ typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; v
 </p></pre><BR>
 
 <pre><b>ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize);
-</b><p>   optimize params for a given `srcSize` and `dictSize`.
-   both values are optional, select `0` if unknown. 
+</b><p>  optimize params for a given `srcSize` and `dictSize`.
+  both values are optional, select `0` if unknown. 
 </p></pre><BR>
 
 <pre><b>size_t ZSTD_compress_advanced (ZSTD_CCtx* cctx,
@@ -451,22 +556,32 @@ typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; v
   Note 3 : Skippable Frame Identifiers are considered valid. 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_estimateDCtxSize(void);
-</b><p>  Gives the potential amount of memory allocated to create a ZSTD_DCtx 
-</p></pre><BR>
-
 <pre><b>ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem);
 </b><p>  Create a ZSTD decompression context using external alloc and free functions 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_sizeof_DCtx(const ZSTD_DCtx* dctx);
-</b><p>  Gives the amount of memory used by a given ZSTD_DCtx 
+<pre><b>ZSTD_DCtx* ZSTD_initStaticDCtx(void* workspace, size_t workspaceSize);
+</b><p>  workspace: The memory area to emplace the context into.
+             Provided pointer must 8-bytes aligned.
+             It must outlive context usage.
+  workspaceSize: Use ZSTD_estimateDCtxSize() or ZSTD_estimateDStreamSize()
+                 to determine how large workspace must be to support scenario.
+ @return : pointer to ZSTD_DCtx*, or NULL if error (size too small)
+  Note : zstd will never resize nor malloc() when using a static dctx.
+         If it needs more memory than available, it will simply error out.
+  Note 2 : static dctx is incompatible with legacy support
+  Note 3 : there is no corresponding "free" function.
+           Since workspace was allocated externally, it must be freed externally.
+  Limitation : currently not compatible with internal DDict creation,
+               such as ZSTD_initDStream_usingDict().
+ 
 </p></pre><BR>
 
 <pre><b>ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize);
 </b><p>  Create a digested dictionary, ready to start decompression operation without startup delay.
-  Dictionary content is simply referenced, and therefore stays in dictBuffer.
-  It is important that dictBuffer outlives DDict, it must remain read accessible throughout the lifetime of DDict 
+  Dictionary content is referenced, and therefore stays in dictBuffer.
+  It is important that dictBuffer outlives DDict,
+  it must remain read accessible throughout the lifetime of DDict 
 </p></pre><BR>
 
 <pre><b>ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize,
@@ -474,8 +589,19 @@ typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; v
 </b><p>  Create a ZSTD_DDict using external alloc and free, optionally by reference 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
-</b><p>  Gives the amount of memory used by a given ZSTD_DDict 
+<pre><b>ZSTD_DDict* ZSTD_initStaticDDict(void* workspace, size_t workspaceSize,
+                                 const void* dict, size_t dictSize,
+                                 unsigned byReference);
+</b><p>  Generate a digested dictionary in provided memory area.
+  workspace: The memory area to emplace the dictionary into.
+             Provided pointer must 8-bytes aligned.
+             It must outlive dictionary usage.
+  workspaceSize: Use ZSTD_estimateDDictSize()
+                 to determine how large workspace must be.
+ @return : pointer to ZSTD_DDict*, or NULL if error (size too small)
+  Note : there is no corresponding "free" function.
+         Since workspace was allocated externally, it must be freed externally.
+ 
 </p></pre><BR>
 
 <pre><b>unsigned ZSTD_getDictID_fromDict(const void* dict, size_t dictSize);
@@ -499,19 +625,19 @@ typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; v
     Note : this use case also happens when using a non-conformant dictionary.
   - `srcSize` is too small, and as a result, the frame header could not be decoded (only possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`).
   - This is not a Zstandard frame.
-  When identifying the exact failure cause, it's possible to use ZSTD_getFrameParams(), which will provide a more precise error code. 
+  When identifying the exact failure cause, it's possible to use ZSTD_getFrameHeader(), which will provide a more precise error code. 
 </p></pre><BR>
 
 <a name="Chapter16"></a><h2>Advanced streaming functions</h2><pre></pre>
 
 <h3>Advanced Streaming compression functions</h3><pre></pre><b><pre>ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem);
-size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs);   </b>/**< size of CStream is variable, depending primarily on compression level */<b>
+ZSTD_CStream* ZSTD_initStaticCStream(void* workspace, size_t workspaceSize);    </b>/**< same as ZSTD_initStaticCCtx() */<b>
 size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize);   </b>/**< pledgedSrcSize must be correct, a size of 0 means unknown.  for a frame size of 0 use initCStream_advanced */<b>
-size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); </b>/**< note: a dict will not be used if dict == NULL or dictSize < 8 */<b>
+size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); </b>/**< creates of an internal CDict (incompatible with static CCtx), except if dict == NULL or dictSize < 8, in which case no dict is used. */<b>
 size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, const void* dict, size_t dictSize,
                                              ZSTD_parameters params, unsigned long long pledgedSrcSize);  </b>/**< pledgedSrcSize is optional and can be 0 (meaning unknown). note: if the contentSizeFlag is set, pledgedSrcSize == 0 means the source size is actually 0 */<b>
 size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict);  </b>/**< note : cdict will just be referenced, and must outlive compression session */<b>
-size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize, ZSTD_frameParameters fParams);  </b>/**< same as ZSTD_initCStream_usingCDict(), with control over frame parameters */<b>
+size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, ZSTD_frameParameters fParams, unsigned long long pledgedSrcSize);  </b>/**< same as ZSTD_initCStream_usingCDict(), with control over frame parameters */<b>
 </pre></b><BR>
 <pre><b>size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
 </b><p>  start a new compression job, using same parameters from previous job.
@@ -524,11 +650,11 @@ size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict*
 
 <h3>Advanced Streaming decompression functions</h3><pre></pre><b><pre>typedef enum { DStream_p_maxWindowSize } ZSTD_DStreamParameter_e;
 ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem);
-size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); </b>/**< note: a dict will not be used if dict == NULL or dictSize < 8 */<b>
+ZSTD_DStream* ZSTD_initStaticDStream(void* workspace, size_t workspaceSize);    </b>/**< same as ZSTD_initStaticDCtx() */<b>
 size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds, ZSTD_DStreamParameter_e paramType, unsigned paramValue);
+size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); </b>/**< note: a dict will not be used if dict == NULL or dictSize < 8 */<b>
 size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict);  </b>/**< note : ddict will just be referenced, and must outlive decompression session */<b>
 size_t ZSTD_resetDStream(ZSTD_DStream* zds);  </b>/**< re-use decompression parameters from previous init; saves dictionary loading */<b>
-size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds);
 </pre></b><BR>
 <a name="Chapter17"></a><h2>Buffer-less and synchronous inner streaming functions</h2><pre>
   This is an advanced API, giving full control over buffer management, for users which need direct control over memory.
@@ -578,21 +704,24 @@ size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned lo
   Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it.
   A ZSTD_DCtx object can be re-used multiple times.
 
-  First typical operation is to retrieve frame parameters, using ZSTD_getFrameParams().
-  It fills a ZSTD_frameParams structure which provide important information to correctly decode the frame,
-  such as the minimum rolling buffer size to allocate to decompress data (`windowSize`),
-  and the dictionary ID used.
+  First typical operation is to retrieve frame parameters, using ZSTD_getFrameHeader().
+  It fills a ZSTD_frameHeader structure with important information to correctly decode the frame,
+  such as minimum rolling buffer size to allocate to decompress data (`windowSize`),
+  and the dictionary ID in use.
   (Note : content size is optional, it may not be present. 0 means : content size unknown).
   Note that these values could be wrong, either because of data malformation, or because an attacker is spoofing deliberate false information.
   As a consequence, check that values remain within valid application range, especially `windowSize`, before allocation.
-  Each application can set its own limit, depending on local restrictions. For extended interoperability, it is recommended to support at least 8 MB.
-  Frame parameters are extracted from the beginning of the compressed frame.
-  Data fragment must be large enough to ensure successful decoding, typically `ZSTD_frameHeaderSize_max` bytes.
-  @result : 0 : successful decoding, the `ZSTD_frameParams` structure is correctly filled.
+  Each application can set its own limit, depending on local restrictions.
+  For extended interoperability, it is recommended to support windowSize of at least 8 MB.
+  Frame header is extracted from the beginning of compressed frame, so providing only the frame's beginning is enough.
+  Data fragment must be large enough to ensure successful decoding.
+  `ZSTD_frameHeaderSize_max` bytes is guaranteed to always be large enough.
+  @result : 0 : successful decoding, the `ZSTD_frameHeader` structure is correctly filled.
            >0 : `srcSize` is too small, please provide at least @result bytes on next attempt.
            errorCode, which can be tested using ZSTD_isError().
 
-  Start decompression, with ZSTD_decompressBegin() or ZSTD_decompressBegin_usingDict().
+  Start decompression, with ZSTD_decompressBegin().
+  If decompression requires a dictionary, use ZSTD_decompressBegin_usingDict() or ZSTD_decompressBegin_usingDDict().
   Alternatively, you can copy a prepared context, using ZSTD_copyDCtx().
 
   Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue() alternatively.
@@ -624,29 +753,196 @@ size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned lo
   b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits
   c) Frame Content - any content (User Data) of length equal to Frame Size
   For skippable frames ZSTD_decompressContinue() always returns 0.
-  For skippable frames ZSTD_getFrameParams() returns fparamsPtr->windowLog==0 what means that a frame is skippable.
+  For skippable frames ZSTD_getFrameHeader() returns fparamsPtr->windowLog==0 what means that a frame is skippable.
     Note : If fparamsPtr->frameContentSize==0, it is ambiguous: the frame might actually be a Zstd encoded frame with no content.
            For purposes of decompression, it is valid in both cases to skip the frame using
            ZSTD_findFrameCompressedSize to find its size in bytes.
   It also returns Frame Size as fparamsPtr->frameContentSize.
 <BR></pre>
 
-<pre><b>typedef struct {
-    unsigned long long frameContentSize;
-    unsigned windowSize;
-    unsigned dictID;
-    unsigned checksumFlag;
-} ZSTD_frameParams;
-</b></pre><BR>
-<h3>Buffer-less streaming decompression functions</h3><pre></pre><b><pre>size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t srcSize);   </b>/**< doesn't consume input, see details below */<b>
+<h3>Buffer-less streaming decompression functions</h3><pre></pre><b><pre>size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize);   </b>/**< doesn't consume input */<b>
 size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx);
 size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
+size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict);
 void   ZSTD_copyDCtx(ZSTD_DCtx* dctx, const ZSTD_DCtx* preparedDCtx);
-size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx);
-size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
-typedef enum { ZSTDnit_frameHeader, ZSTDnit_blockHeader, ZSTDnit_block, ZSTDnit_lastBlock, ZSTDnit_checksum, ZSTDnit_skippableFrame } ZSTD_nextInputType_e;
-ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
 </pre></b><BR>
+<pre><b>typedef enum { ZSTDnit_frameHeader, ZSTDnit_blockHeader, ZSTDnit_block, ZSTDnit_lastBlock, ZSTDnit_checksum, ZSTDnit_skippableFrame } ZSTD_nextInputType_e;
+</b></pre><BR>
+<h3>New advanced API (experimental, and compression only)</h3><pre></pre><b><pre></pre></b><BR>
+<pre><b>typedef enum {
+    </b>/* compression parameters */<b>
+    ZSTD_p_compressionLevel=100, </b>/* Update all compression parameters according to pre-defined cLevel table<b>
+                              * Default level is ZSTD_CLEVEL_DEFAULT==3.
+                              * Special: value 0 means "do not change cLevel". */
+    ZSTD_p_windowLog,        </b>/* Maximum allowed back-reference distance, expressed as power of 2.<b>
+                              * Must be clamped between ZSTD_WINDOWLOG_MIN and ZSTD_WINDOWLOG_MAX.
+                              * Special: value 0 means "do not change windowLog". */
+    ZSTD_p_hashLog,          </b>/* Size of the probe table, as a power of 2.<b>
+                              * Resulting table size is (1 << (hashLog+2)).
+                              * Must be clamped between ZSTD_HASHLOG_MIN and ZSTD_HASHLOG_MAX.
+                              * Larger tables improve compression ratio of strategies <= dFast,
+                              * and improve speed of strategies > dFast.
+                              * Special: value 0 means "do not change hashLog". */
+    ZSTD_p_chainLog,         </b>/* Size of the full-search table, as a power of 2.<b>
+                              * Resulting table size is (1 << (chainLog+2)).
+                              * Larger tables result in better and slower compression.
+                              * This parameter is useless when using "fast" strategy.
+                              * Special: value 0 means "do not change chainLog". */
+    ZSTD_p_searchLog,        </b>/* Number of search attempts, as a power of 2.<b>
+                              * More attempts result in better and slower compression.
+                              * This parameter is useless when using "fast" and "dFast" strategies.
+                              * Special: value 0 means "do not change searchLog". */
+    ZSTD_p_minMatch,         </b>/* Minimum size of searched matches (note : repCode matches can be smaller).<b>
+                              * Larger values make faster compression and decompression, but decrease ratio.
+                              * Must be clamped between ZSTD_SEARCHLENGTH_MIN and ZSTD_SEARCHLENGTH_MAX.
+                              * Note that currently, for all strategies < btopt, effective minimum is 4.
+                              * Note that currently, for all strategies > fast, effective maximum is 6.
+                              * Special: value 0 means "do not change minMatchLength". */
+    ZSTD_p_targetLength,     </b>/* Only useful for strategies >= btopt.<b>
+                              * Length of Match considered "good enough" to stop search.
+                              * Larger values make compression stronger and slower.
+                              * Special: value 0 means "do not change targetLength". */
+    ZSTD_p_compressionStrategy, </b>/* See ZSTD_strategy enum definition.<b>
+                              * Cast selected strategy as unsigned for ZSTD_CCtx_setParameter() compatibility.
+                              * The higher the value of selected strategy, the more complex it is,
+                              * resulting in stronger and slower compression.
+                              * Special: value 0 means "do not change strategy". */
+
+    </b>/* frame parameters */<b>
+    ZSTD_p_contentSizeFlag=200, </b>/* Content size is written into frame header _whenever known_ (default:1) */<b>
+    ZSTD_p_checksumFlag,     </b>/* A 32-bits checksum of content is written at end of frame (default:0) */<b>
+    ZSTD_p_dictIDFlag,       </b>/* When applicable, dictID of dictionary is provided in frame header (default:1) */<b>
+
+    </b>/* dictionary parameters (must be set before ZSTD_CCtx_loadDictionary) */<b>
+    ZSTD_p_dictMode=300,     </b>/* Select how dictionary content must be interpreted. Value must be from type ZSTD_dictMode_e.<b>
+                              * default : 0==auto : dictionary will be "full" if it respects specification, otherwise it will be "rawContent" */
+    ZSTD_p_refDictContent,   </b>/* Dictionary content will be referenced, instead of copied (default:0==byCopy).<b>
+                              * It requires that dictionary buffer outlives its users */
+
+    </b>/* multi-threading parameters */<b>
+    ZSTD_p_nbThreads=400,    </b>/* Select how many threads a compression job can spawn (default:1)<b>
+                              * More threads improve speed, but also increase memory usage.
+                              * Can only receive a value > 1 if ZSTD_MULTITHREAD is enabled.
+                              * Special: value 0 means "do not change nbThreads" */
+    ZSTD_p_jobSize,          </b>/* Size of a compression job. Each compression job is completed in parallel.<b>
+                              * 0 means default, which is dynamically determined based on compression parameters.
+                              * Job size must be a minimum of overlapSize, or 1 KB, whichever is largest
+                              * The minimum size is automatically and transparently enforced */
+    ZSTD_p_overlapSizeLog,   </b>/* Size of previous input reloaded at the beginning of each job.<b>
+                              * 0 => no overlap, 6(default) => use 1/8th of windowSize, >=9 => use full windowSize */
+
+    </b>/* advanced parameters - may not remain available after API update */<b>
+    ZSTD_p_forceMaxWindow=1100, </b>/* Force back-reference distances to remain < windowSize,<b>
+                              * even when referencing into Dictionary content (default:0) */
+
+} ZSTD_cParameter;
+</b></pre><BR>
+<pre><b>size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned value);
+</b><p>  Set one compression parameter, selected by enum ZSTD_cParameter.
+  Note : when `value` is an enum, cast it to unsigned for proper type checking.
+  @result : 0, or an error code (which can be tested with ZSTD_isError()). 
+</p></pre><BR>
+
+<pre><b>size_t ZSTD_CCtx_setPledgedSrcSize(ZSTD_CCtx* cctx, unsigned long long pledgedSrcSize);
+</b><p>  Total input data size to be compressed as a single frame.
+  This value will be controlled at the end, and result in error if not respected.
+ @result : 0, or an error code (which can be tested with ZSTD_isError()).
+  Note 1 : 0 means zero, empty.
+           In order to mean "unknown content size", pass constant ZSTD_CONTENTSIZE_UNKNOWN.
+           Note that ZSTD_CONTENTSIZE_UNKNOWN is default value for new compression jobs.
+  Note 2 : If all data is provided and consumed in a single round,
+           this value is overriden by srcSize instead. 
+</p></pre><BR>
+
+<pre><b>size_t ZSTD_CCtx_loadDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize);
+</b><p>  Create an internal CDict from dict buffer.
+  Decompression will have to use same buffer.
+ @result : 0, or an error code (which can be tested with ZSTD_isError()).
+  Special : Adding a NULL (or 0-size) dictionary invalidates any previous dictionary,
+            meaning "return to no-dictionary mode".
+  Note 1 : `dict` content will be copied internally,
+           except if ZSTD_p_refDictContent is set before loading.
+  Note 2 : Loading a dictionary involves building tables, which are dependent on compression parameters.
+           For this reason, compression parameters cannot be changed anymore after loading a dictionary.
+           It's also a CPU-heavy operation, with non-negligible impact on latency.
+  Note 3 : Dictionary will be used for all future compression jobs.
+           To return to "no-dictionary" situation, load a NULL dictionary 
+</p></pre><BR>
+
+<pre><b>size_t ZSTD_CCtx_refCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict);
+</b><p>  Reference a prepared dictionary, to be used for all next compression jobs.
+  Note that compression parameters are enforced from within CDict,
+  and supercede any compression parameter previously set within CCtx.
+  The dictionary will remain valid for future compression jobs using same CCtx.
+ @result : 0, or an error code (which can be tested with ZSTD_isError()).
+  Special : adding a NULL CDict means "return to no-dictionary mode".
+  Note 1 : Currently, only one dictionary can be managed.
+           Adding a new dictionary effectively "discards" any previous one.
+  Note 2 : CDict is just referenced, its lifetime must outlive CCtx.
+ 
+</p></pre><BR>
+
+<pre><b>size_t ZSTD_CCtx_refPrefix(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize);
+</b><p>  Reference a prefix (single-usage dictionary) for next compression job.
+  Decompression need same prefix to properly regenerate data.
+  Prefix is **only used once**. Tables are discarded at end of compression job.
+  Subsequent compression jobs will be done without prefix (if none is explicitly referenced).
+  If there is a need to use same prefix multiple times, consider embedding it into a ZSTD_CDict instead.
+ @result : 0, or an error code (which can be tested with ZSTD_isError()).
+  Special : Adding any prefix (including NULL) invalidates any previous prefix or dictionary
+  Note 1 : Prefix buffer is referenced. It must outlive compression job.
+  Note 2 : Referencing a prefix involves building tables, which are dependent on compression parameters.
+           It's a CPU-heavy operation, with non-negligible impact on latency.
+  Note 3 : it's possible to alter ZSTD_p_dictMode using ZSTD_CCtx_setParameter() 
+</p></pre><BR>
+
+<pre><b>typedef enum {
+    ZSTD_e_continue=0, </b>/* collect more data, encoder transparently decides when to output result, for optimal conditions */<b>
+    ZSTD_e_flush,      </b>/* flush any data provided so far - frame will continue, future data can still reference previous data for better compression */<b>
+    ZSTD_e_end         </b>/* flush any remaining data and ends current frame. Any future compression starts a new frame. */<b>
+} ZSTD_EndDirective;
+</b></pre><BR>
+<pre><b>size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
+                              ZSTD_outBuffer* output,
+                              ZSTD_inBuffer* input,
+                              ZSTD_EndDirective endOp);
+</b><p>  Behave about the same as ZSTD_compressStream. To note :
+  - Compression parameters are pushed into CCtx before starting compression, using ZSTD_CCtx_setParameter()
+  - Compression parameters cannot be changed once compression is started.
+  - *dstPos must be <= dstCapacity, *srcPos must be <= srcSize
+  - *dspPos and *srcPos will be updated. They are guaranteed to remain below their respective limit.
+  - @return provides the minimum amount of data still to flush from internal buffers
+            or an error code, which can be tested using ZSTD_isError().
+            if @return != 0, flush is not fully completed, there is some data left within internal buffers.
+  - after a ZSTD_e_end directive, if internal buffer is not fully flushed,
+            only ZSTD_e_end or ZSTD_e_flush operations are allowed.
+            It is necessary to fully flush internal buffers
+            before starting a new compression job, or changing compression parameters.
+ 
+</p></pre><BR>
+
+<pre><b>void ZSTD_CCtx_reset(ZSTD_CCtx* cctx);   </b>/* Not ready yet ! */<b>
+</b><p>  Return a CCtx to clean state.
+  Useful after an error, or to interrupt an ongoing compression job and start a new one.
+  Any internal data not yet flushed is cancelled.
+  Dictionary (if any) is dropped.
+  It's possible to modify compression parameters after a reset.
+ 
+</p></pre><BR>
+
+<pre><b>size_t ZSTD_compress_generic_simpleArgs (
+                ZSTD_CCtx* cctx,
+                void* dst, size_t dstCapacity, size_t* dstPos,
+          const void* src, size_t srcSize, size_t* srcPos,
+                ZSTD_EndDirective endOp);
+</b><p>  Same as ZSTD_compress_generic(),
+  but using only integral types as arguments.
+  Argument list is larger and less expressive than ZSTD_{in,out}Buffer,
+  but can be helpful for binders from dynamic languages
+  which have troubles handling structures containing memory pointers.
+ 
+</p></pre><BR>
+
 <a name="Chapter20"></a><h2>Block functions</h2><pre>
     Block functions produce and decode raw zstd blocks, without frame metadata.
     Frame metadata cost is typically ~18 bytes, which can be non-negligible for very small blocks (< 100 bytes).
@@ -659,7 +955,7 @@ ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
       + compression : any ZSTD_compressBegin*() variant, including with dictionary
       + decompression : any ZSTD_decompressBegin*() variant, including with dictionary
       + copyCCtx() and copyDCtx() can be used too
-    - Block size is limited, it must be <= ZSTD_getBlockSizeMax() <= ZSTD_BLOCKSIZE_ABSOLUTEMAX
+    - Block size is limited, it must be <= ZSTD_getBlockSize() <= ZSTD_BLOCKSIZE_MAX
       + If input is larger than a block size, it's necessary to split input data into multiple blocks
       + For inputs larger than a single block size, consider using the regular ZSTD_compress() instead.
         Frame metadata is not that costly, and quickly becomes negligible as source size grows larger.
@@ -672,7 +968,7 @@ ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
         Use ZSTD_insertBlock() for such a case.
 <BR></pre>
 
-<h3>Raw zstd block functions</h3><pre></pre><b><pre>size_t ZSTD_getBlockSizeMax(ZSTD_CCtx* cctx);
+<h3>Raw zstd block functions</h3><pre></pre><b><pre>size_t ZSTD_getBlockSize   (const ZSTD_CCtx* cctx);
 size_t ZSTD_compressBlock  (ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 size_t ZSTD_insertBlock(ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize);  </b>/**< insert block into `dctx` history. Useful for uncompressed blocks */<b>
diff --git a/examples/Makefile b/examples/Makefile
index b84983f08c0c..e279a537d71e 100644
--- a/examples/Makefile
+++ b/examples/Makefile
@@ -46,7 +46,7 @@ clean:
         simple_compression simple_decompression \
         dictionary_compression dictionary_decompression \
         streaming_compression streaming_decompression \
-		multiple_streaming_compression
+        multiple_streaming_compression
 	@echo Cleaning completed
 
 test: all
diff --git a/lib/Makefile b/lib/Makefile
index d8d8e179d205..5845cf170e71 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -22,9 +22,11 @@ VERSION?= $(LIBVER)
 
 CPPFLAGS+= -I. -I./common -DXXH_NAMESPACE=ZSTD_
 CFLAGS  ?= -O3
-DEBUGFLAGS = -g -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
-           -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
-           -Wstrict-prototypes -Wundef -Wpointer-arith -Wformat-security
+DEBUGFLAGS = -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
+            -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
+            -Wstrict-prototypes -Wundef -Wpointer-arith -Wformat-security \
+            -Wvla -Wformat=2 -Winit-self -Wfloat-equal -Wwrite-strings \
+            -Wredundant-decls
 CFLAGS  += $(DEBUGFLAGS) $(MOREFLAGS)
 FLAGS    = $(CPPFLAGS) $(CFLAGS)
 
@@ -71,7 +73,7 @@ libzstd.a: $(ZSTD_OBJ)
 	@echo compiling static library
 	@$(AR) $(ARFLAGS) $@ $^
 
-libzstd.a-mt: CPPFLAGS += -DZSTD_MULTHREAD
+libzstd.a-mt: CPPFLAGS += -DZSTD_MULTITHREAD
 libzstd.a-mt: libzstd.a
 
 $(LIBZSTD): LDFLAGS += -shared -fPIC -fvisibility=hidden
@@ -147,7 +149,7 @@ install: libzstd.a libzstd libzstd.pc
 	@$(INSTALL) -d -m 755 $(DESTDIR)$(PKGCONFIGDIR)/ $(DESTDIR)$(INCLUDEDIR)/
 	@$(INSTALL_DATA) libzstd.pc $(DESTDIR)$(PKGCONFIGDIR)/
 	@echo Installing libraries
-	@$(INSTALL_LIB) libzstd.a $(DESTDIR)$(LIBDIR)
+	@$(INSTALL_DATA) libzstd.a $(DESTDIR)$(LIBDIR)
 	@$(INSTALL_LIB) libzstd.$(SHARED_EXT_VER) $(DESTDIR)$(LIBDIR)
 	@ln -sf libzstd.$(SHARED_EXT_VER) $(DESTDIR)$(LIBDIR)/libzstd.$(SHARED_EXT_MAJOR)
 	@ln -sf libzstd.$(SHARED_EXT_VER) $(DESTDIR)$(LIBDIR)/libzstd.$(SHARED_EXT)
diff --git a/lib/common/bitstream.h b/lib/common/bitstream.h
index ca42850df324..07b85026c95b 100644
--- a/lib/common/bitstream.h
+++ b/lib/common/bitstream.h
@@ -39,7 +39,6 @@
 extern "C" {
 #endif
 
-
 /*
 *  This API consists of small unitary functions, which must be inlined for best performance.
 *  Since link-time-optimization is not available for all compilers,
@@ -59,7 +58,9 @@ extern "C" {
 #if defined(BIT_DEBUG) && (BIT_DEBUG>=1)
 #  include <assert.h>
 #else
-#  define assert(condition) ((void)0)
+#  ifndef assert
+#    define assert(condition) ((void)0)
+#  endif
 #endif
 
 
@@ -74,6 +75,7 @@ extern "C" {
 #define STREAM_ACCUMULATOR_MIN_64  57
 #define STREAM_ACCUMULATOR_MIN    ((U32)(MEM_32bits() ? STREAM_ACCUMULATOR_MIN_32 : STREAM_ACCUMULATOR_MIN_64))
 
+
 /*-******************************************
 *  bitStream encoding API (write forward)
 ********************************************/
@@ -303,13 +305,25 @@ MEM_STATIC size_t BIT_initDStream(BIT_DStream_t* bitD, const void* srcBuffer, si
         bitD->bitContainer = *(const BYTE*)(bitD->start);
         switch(srcSize)
         {
-            case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);
-            case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);
-            case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);
-            case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24;
-            case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16;
-            case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) <<  8;
-            default:;
+	    case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);
+	            /* fall-through */
+
+	    case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);
+	            /* fall-through */
+
+	    case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);
+	            /* fall-through */
+
+	    case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24;
+	            /* fall-through */
+
+	    case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16;
+	            /* fall-through */
+
+	    case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) <<  8;
+	            /* fall-through */
+
+            default: break;
         }
         { BYTE const lastByte = ((const BYTE*)srcBuffer)[srcSize-1];
           bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0;
diff --git a/lib/common/error_private.c b/lib/common/error_private.c
index b3287245f1ee..2d752cd23a72 100644
--- a/lib/common/error_private.c
+++ b/lib/common/error_private.c
@@ -24,7 +24,8 @@ const char* ERR_getErrorString(ERR_enum code)
     case PREFIX(frameParameter_unsupported): return "Unsupported frame parameter";
     case PREFIX(frameParameter_unsupportedBy32bits): return "Frame parameter unsupported in 32-bits mode";
     case PREFIX(frameParameter_windowTooLarge): return "Frame requires too much memory for decoding";
-    case PREFIX(compressionParameter_unsupported): return "Compression parameter is out of bound";
+    case PREFIX(compressionParameter_unsupported): return "Compression parameter is not supported";
+    case PREFIX(compressionParameter_outOfBound): return "Compression parameter is out of bound";
     case PREFIX(init_missing): return "Context should be init first";
     case PREFIX(memory_allocation): return "Allocation error : not enough memory";
     case PREFIX(stage_wrong): return "Operation not authorized at current processing stage";
@@ -38,6 +39,8 @@ const char* ERR_getErrorString(ERR_enum code)
     case PREFIX(dictionary_corrupted): return "Dictionary is corrupted";
     case PREFIX(dictionary_wrong): return "Dictionary mismatch";
     case PREFIX(dictionaryCreation_failed): return "Cannot create Dictionary from provided samples";
+    case PREFIX(frameIndex_tooLarge): return "Frame index is too large";
+    case PREFIX(seekableIO): return "An I/O error occurred when reading/seeking";
     case PREFIX(maxCode):
     default: return notErrorCode;
     }
diff --git a/lib/common/huf.h b/lib/common/huf.h
index 7873ca3d42a5..dabd359915a7 100644
--- a/lib/common/huf.h
+++ b/lib/common/huf.h
@@ -111,6 +111,18 @@ HUF_PUBLIC_API size_t HUF_compress2 (void* dst, size_t dstCapacity, const void*
 #define HUF_WORKSPACE_SIZE_U32 (HUF_WORKSPACE_SIZE / sizeof(U32))
 HUF_PUBLIC_API size_t HUF_compress4X_wksp (void* dst, size_t dstCapacity, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize);
 
+/**
+ *  The minimum workspace size for the `workSpace` used in
+ *  HUF_readDTableX2_wksp() and HUF_readDTableX4_wksp().
+ *
+ *  The space used depends on HUF_TABLELOG_MAX, ranging from ~1500 bytes when
+ *  HUF_TABLE_LOG_MAX=12 to ~1850 bytes when HUF_TABLE_LOG_MAX=15.
+ *  Buffer overflow errors may potentially occur if code modifications result in
+ *  a required workspace size greater than that specified in the following
+ *  macro.
+ */
+#define HUF_DECOMPRESS_WORKSPACE_SIZE (2 << 10)
+#define HUF_DECOMPRESS_WORKSPACE_SIZE_U32 (HUF_DECOMPRESS_WORKSPACE_SIZE / sizeof(U32))
 
 
 /* ******************************************************************
@@ -170,8 +182,11 @@ size_t HUF_decompress4X4 (void* dst, size_t dstSize, const void* cSrc, size_t cS
 
 size_t HUF_decompress4X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /**< decodes RLE and uncompressed */
 size_t HUF_decompress4X_hufOnly(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /**< considers RLE and uncompressed as errors */
+size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize); /**< considers RLE and uncompressed as errors */
 size_t HUF_decompress4X2_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /**< single-symbol decoder */
+size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);   /**< single-symbol decoder */
 size_t HUF_decompress4X4_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /**< double-symbols decoder */
+size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);   /**< double-symbols decoder */
 
 
 /* ****************************************
@@ -243,7 +258,9 @@ HUF_decompress() does the following:
 U32 HUF_selectDecoder (size_t dstSize, size_t cSrcSize);
 
 size_t HUF_readDTableX2 (HUF_DTable* DTable, const void* src, size_t srcSize);
+size_t HUF_readDTableX2_wksp (HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize);
 size_t HUF_readDTableX4 (HUF_DTable* DTable, const void* src, size_t srcSize);
+size_t HUF_readDTableX4_wksp (HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize);
 
 size_t HUF_decompress4X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
 size_t HUF_decompress4X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
@@ -266,8 +283,11 @@ size_t HUF_decompress1X2 (void* dst, size_t dstSize, const void* cSrc, size_t cS
 size_t HUF_decompress1X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /* double-symbol decoder */
 
 size_t HUF_decompress1X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);
+size_t HUF_decompress1X_DCtx_wksp (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);
 size_t HUF_decompress1X2_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /**< single-symbol decoder */
+size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);   /**< single-symbol decoder */
 size_t HUF_decompress1X4_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /**< double-symbols decoder */
+size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);   /**< double-symbols decoder */
 
 size_t HUF_decompress1X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);   /**< automatic selection of sing or double symbol decoder, based on DTable */
 size_t HUF_decompress1X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
diff --git a/lib/common/mem.h b/lib/common/mem.h
index 4773a8b9309e..b0e5bf60b43b 100644
--- a/lib/common/mem.h
+++ b/lib/common/mem.h
@@ -352,20 +352,6 @@ MEM_STATIC void MEM_writeBEST(void* memPtr, size_t val)
 }
 
 
-/* function safe only for comparisons */
-MEM_STATIC U32 MEM_readMINMATCH(const void* memPtr, U32 length)
-{
-    switch (length)
-    {
-    default :
-    case 4 : return MEM_read32(memPtr);
-    case 3 : if (MEM_isLittleEndian())
-                return MEM_read32(memPtr)<<8;
-             else
-                return MEM_read32(memPtr)>>8;
-    }
-}
-
 #if defined (__cplusplus)
 }
 #endif
diff --git a/lib/common/pool.c b/lib/common/pool.c
index e439fe1b0dd6..749fa4f2f7b4 100644
--- a/lib/common/pool.c
+++ b/lib/common/pool.c
@@ -146,6 +146,13 @@ void POOL_free(POOL_ctx *ctx) {
     free(ctx);
 }
 
+size_t POOL_sizeof(POOL_ctx *ctx) {
+    if (ctx==NULL) return 0;  /* supports sizeof NULL */
+    return sizeof(*ctx)
+        + ctx->queueSize * sizeof(POOL_job)
+        + ctx->numThreads * sizeof(pthread_t);
+}
+
 void POOL_add(void *ctxVoid, POOL_function function, void *opaque) {
     POOL_ctx *ctx = (POOL_ctx *)ctxVoid;
     if (!ctx) { return; }
@@ -191,4 +198,9 @@ void POOL_add(void *ctx, POOL_function function, void *opaque) {
   function(opaque);
 }
 
+size_t POOL_sizeof(POOL_ctx *ctx) {
+    if (ctx==NULL) return 0;  /* supports sizeof NULL */
+    return sizeof(*ctx);
+}
+
 #endif  /* ZSTD_MULTITHREAD */
diff --git a/lib/common/pool.h b/lib/common/pool.h
index 50cb25b12c9f..386cd674b7c0 100644
--- a/lib/common/pool.h
+++ b/lib/common/pool.h
@@ -32,6 +32,11 @@ POOL_ctx *POOL_create(size_t numThreads, size_t queueSize);
 */
 void POOL_free(POOL_ctx *ctx);
 
+/*! POOL_sizeof() :
+    return memory usage of pool returned by POOL_create().
+*/
+size_t POOL_sizeof(POOL_ctx *ctx);
+
 /*! POOL_function :
     The function type that can be added to a thread pool.
 */
diff --git a/lib/common/threading.c b/lib/common/threading.c
index 32d58796a9ea..141376c56199 100644
--- a/lib/common/threading.c
+++ b/lib/common/threading.c
@@ -1,4 +1,3 @@
-
 /**
  * Copyright (c) 2016 Tino Reichardt
  * All rights reserved.
diff --git a/lib/common/zstd_common.c b/lib/common/zstd_common.c
index 8408a589ae8d..f68167238158 100644
--- a/lib/common/zstd_common.c
+++ b/lib/common/zstd_common.c
@@ -12,16 +12,19 @@
 /*-*************************************
 *  Dependencies
 ***************************************/
-#include <stdlib.h>         /* malloc */
+#include <stdlib.h>      /* malloc, calloc, free */
+#include <string.h>      /* memset */
 #include "error_private.h"
 #define ZSTD_STATIC_LINKING_ONLY
-#include "zstd.h"           /* declaration of ZSTD_isError, ZSTD_getErrorName, ZSTD_getErrorCode, ZSTD_getErrorString, ZSTD_versionNumber */
+#include "zstd.h"
 
 
 /*-****************************************
 *  Version
 ******************************************/
-unsigned ZSTD_versionNumber (void) { return ZSTD_VERSION_NUMBER; }
+unsigned ZSTD_versionNumber(void) { return ZSTD_VERSION_NUMBER; }
+
+const char* ZSTD_versionString(void) { return ZSTD_VERSION_STRING; }
 
 
 /*-****************************************
@@ -47,27 +50,31 @@ const char* ZSTD_getErrorString(ZSTD_ErrorCode code) { return ERR_getErrorString
 /*=**************************************************************
 *  Custom allocator
 ****************************************************************/
-/* default uses stdlib */
-void* ZSTD_defaultAllocFunction(void* opaque, size_t size)
-{
-    void* address = malloc(size);
-    (void)opaque;
-    return address;
-}
-
-void ZSTD_defaultFreeFunction(void* opaque, void* address)
+void* ZSTD_malloc(size_t size, ZSTD_customMem customMem)
 {
-    (void)opaque;
-    free(address);
+    if (customMem.customAlloc)
+        return customMem.customAlloc(customMem.opaque, size);
+    return malloc(size);
 }
 
-void* ZSTD_malloc(size_t size, ZSTD_customMem customMem)
+void* ZSTD_calloc(size_t size, ZSTD_customMem customMem)
 {
-    return customMem.customAlloc(customMem.opaque, size);
+    if (customMem.customAlloc) {
+        /* calloc implemented as malloc+memset;
+         * not as efficient as calloc, but next best guess for custom malloc */
+        void* const ptr = customMem.customAlloc(customMem.opaque, size);
+        memset(ptr, 0, size);
+        return ptr;
+    }
+    return calloc(1, size);
 }
 
 void ZSTD_free(void* ptr, ZSTD_customMem customMem)
 {
-    if (ptr!=NULL)
-        customMem.customFree(customMem.opaque, ptr);
+    if (ptr!=NULL) {
+        if (customMem.customFree)
+            customMem.customFree(customMem.opaque, ptr);
+        else
+            free(ptr);
+    }
 }
diff --git a/lib/common/zstd_errors.h b/lib/common/zstd_errors.h
index 3d579d969363..19f1597aa340 100644
--- a/lib/common/zstd_errors.h
+++ b/lib/common/zstd_errors.h
@@ -19,10 +19,12 @@ extern "C" {
 
 
 /* =====   ZSTDERRORLIB_API : control library symbols visibility   ===== */
-#if defined(__GNUC__) && (__GNUC__ >= 4)
-#  define ZSTDERRORLIB_VISIBILITY __attribute__ ((visibility ("default")))
-#else
-#  define ZSTDERRORLIB_VISIBILITY
+#ifndef ZSTDERRORLIB_VISIBILITY
+#  if defined(__GNUC__) && (__GNUC__ >= 4)
+#    define ZSTDERRORLIB_VISIBILITY __attribute__ ((visibility ("default")))
+#  else
+#    define ZSTDERRORLIB_VISIBILITY
+#  endif
 #endif
 #if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1)
 #  define ZSTDERRORLIB_API __declspec(dllexport) ZSTDERRORLIB_VISIBILITY
@@ -33,8 +35,11 @@ extern "C" {
 #endif
 
 /*-****************************************
-*  error codes list
-******************************************/
+ *  error codes list
+ *  note : this API is still considered unstable
+ *         it should not be used with a dynamic library
+ *         only static linking is allowed
+ ******************************************/
 typedef enum {
   ZSTD_error_no_error,
   ZSTD_error_GENERIC,
@@ -45,6 +50,7 @@ typedef enum {
   ZSTD_error_frameParameter_unsupportedBy32bits,
   ZSTD_error_frameParameter_windowTooLarge,
   ZSTD_error_compressionParameter_unsupported,
+  ZSTD_error_compressionParameter_outOfBound,
   ZSTD_error_init_missing,
   ZSTD_error_memory_allocation,
   ZSTD_error_stage_wrong,
@@ -58,12 +64,14 @@ typedef enum {
   ZSTD_error_dictionary_corrupted,
   ZSTD_error_dictionary_wrong,
   ZSTD_error_dictionaryCreation_failed,
+  ZSTD_error_frameIndex_tooLarge,
+  ZSTD_error_seekableIO,
   ZSTD_error_maxCode
 } ZSTD_ErrorCode;
 
 /*! ZSTD_getErrorCode() :
     convert a `size_t` function result into a `ZSTD_ErrorCode` enum type,
-    which can be used to compare directly with enum list published into "error_public.h" */
+    which can be used to compare with enum list published above */
 ZSTDERRORLIB_API ZSTD_ErrorCode ZSTD_getErrorCode(size_t functionResult);
 ZSTDERRORLIB_API const char* ZSTD_getErrorString(ZSTD_ErrorCode code);
 
diff --git a/lib/common/zstd_internal.h b/lib/common/zstd_internal.h
index 2533333ba83c..f2c4e6249fb8 100644
--- a/lib/common/zstd_internal.h
+++ b/lib/common/zstd_internal.h
@@ -18,6 +18,7 @@
 #  include <intrin.h>                    /* For Visual 2005 */
 #  pragma warning(disable : 4100)        /* disable: C4100: unreferenced formal parameter */
 #  pragma warning(disable : 4127)        /* disable: C4127: conditional expression is constant */
+#  pragma warning(disable : 4204)        /* disable: C4204: non-constant aggregate initializer */
 #  pragma warning(disable : 4324)        /* disable: C4324: padded structure */
 #else
 #  if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L   /* C99 */
@@ -50,9 +51,42 @@
 #define ZSTD_STATIC_LINKING_ONLY
 #include "zstd.h"
 #ifndef XXH_STATIC_LINKING_ONLY
-#  define XXH_STATIC_LINKING_ONLY   /* XXH64_state_t */
+#  define XXH_STATIC_LINKING_ONLY  /* XXH64_state_t */
+#endif
+#include "xxhash.h"                /* XXH_reset, update, digest */
+
+
+/*-*************************************
+*  Debug
+***************************************/
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
+#  include <assert.h>
+#else
+#  ifndef assert
+#    define assert(condition) ((void)0)
+#  endif
+#endif
+
+#define ZSTD_STATIC_ASSERT(c) { enum { ZSTD_static_assert = 1/(int)(!!(c)) }; }
+
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=2)
+#  include <stdio.h>
+/* recommended values for ZSTD_DEBUG display levels :
+ * 1 : no display, enables assert() only
+ * 2 : reserved for currently active debugging path
+ * 3 : events once per object lifetime (CCtx, CDict)
+ * 4 : events once per frame
+ * 5 : events once per block
+ * 6 : events once per sequence (*very* verbose) */
+#  define DEBUGLOG(l, ...) {                         \
+                if (l<=ZSTD_DEBUG) {                 \
+                    fprintf(stderr, __FILE__ ": ");  \
+                    fprintf(stderr, __VA_ARGS__);    \
+                    fprintf(stderr, " \n");          \
+            }   }
+#else
+#  define DEBUGLOG(l, ...)      {}    /* disabled */
 #endif
-#include "xxhash.h"               /* XXH_reset, update, digest */
 
 
 /*-*************************************
@@ -70,7 +104,6 @@
 *  Common constants
 ***************************************/
 #define ZSTD_OPT_NUM    (1<<12)
-#define ZSTD_DICT_MAGIC  0xEC30A437   /* v0.7+ */
 
 #define ZSTD_REP_NUM      3                 /* number of repcodes */
 #define ZSTD_REP_CHECK    (ZSTD_REP_NUM)    /* number of repcodes to check by the optimal parser */
@@ -235,15 +268,10 @@ typedef struct {
 
 const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx);
 void ZSTD_seqToCodes(const seqStore_t* seqStorePtr);
-int ZSTD_isSkipFrame(ZSTD_DCtx* dctx);
 
 /* custom memory allocation functions */
-void* ZSTD_defaultAllocFunction(void* opaque, size_t size);
-void ZSTD_defaultFreeFunction(void* opaque, void* address);
-#ifndef ZSTD_DLL_IMPORT
-static const ZSTD_customMem defaultCustomMem = { ZSTD_defaultAllocFunction, ZSTD_defaultFreeFunction, NULL };
-#endif
 void* ZSTD_malloc(size_t size, ZSTD_customMem customMem);
+void* ZSTD_calloc(size_t size, ZSTD_customMem customMem);
 void ZSTD_free(void* ptr, ZSTD_customMem customMem);
 
 
@@ -281,4 +309,26 @@ MEM_STATIC U32 ZSTD_highbit32(U32 val)
 void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx);
 
 
+/*! ZSTD_initCStream_internal() :
+ *  Private use only. Init streaming operation.
+ *  expects params to be valid.
+ *  must receive dict, or cdict, or none, but not both.
+ *  @return : 0, or an error code */
+size_t ZSTD_initCStream_internal(ZSTD_CStream* zcs,
+                     const void* dict, size_t dictSize,
+                     const ZSTD_CDict* cdict,
+                     ZSTD_parameters params, unsigned long long pledgedSrcSize);
+
+/*! ZSTD_compressStream_generic() :
+ *  Private use only. To be called from zstdmt_compress.c in single-thread mode. */
+size_t ZSTD_compressStream_generic(ZSTD_CStream* zcs,
+                                   ZSTD_outBuffer* output,
+                                   ZSTD_inBuffer* input,
+                                   ZSTD_EndDirective const flushMode);
+
+/*! ZSTD_getParamsFromCDict() :
+ *  as the name implies */
+ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict* cdict);
+
+
 #endif   /* ZSTD_CCOMMON_H_MODULE */
diff --git a/lib/compress/huf_compress.c b/lib/compress/huf_compress.c
index fe11aafb8f14..7af0789a9c58 100644
--- a/lib/compress/huf_compress.c
+++ b/lib/compress/huf_compress.c
@@ -266,7 +266,8 @@ static U32 HUF_setMaxHeight(nodeElt* huffNode, U32 lastNonNull, U32 maxNbBits)
                         if (highTotal <= lowTotal) break;
                 }   }
                 /* only triggered when no more rank 1 symbol left => find closest one (note : there is necessarily at least one !) */
-                while ((nBitsToDecrease<=HUF_TABLELOG_MAX) && (rankLast[nBitsToDecrease] == noSymbol))  /* HUF_MAX_TABLELOG test just to please gcc 5+; but it should not be necessary */
+                /* HUF_MAX_TABLELOG test just to please gcc 5+; but it should not be necessary */
+                while ((nBitsToDecrease<=HUF_TABLELOG_MAX) && (rankLast[nBitsToDecrease] == noSymbol))
                     nBitsToDecrease ++;
                 totalCost -= 1 << (nBitsToDecrease-1);
                 if (rankLast[nBitsToDecrease-1] == noSymbol)
@@ -463,12 +464,15 @@ size_t HUF_compress1X_usingCTable(void* dst, size_t dstSize, const void* src, si
     {
         case 3 : HUF_encodeSymbol(&bitC, ip[n+ 2], CTable);
                  HUF_FLUSHBITS_2(&bitC);
+		 /* fall-through */
         case 2 : HUF_encodeSymbol(&bitC, ip[n+ 1], CTable);
                  HUF_FLUSHBITS_1(&bitC);
+		 /* fall-through */
         case 1 : HUF_encodeSymbol(&bitC, ip[n+ 0], CTable);
                  HUF_FLUSHBITS(&bitC);
-        case 0 :
-        default: ;
+		 /* fall-through */
+        case 0 : /* fall-through */
+        default: break;
     }
 
     for (; n>0; n-=4) {  /* note : n&3==0 at this stage */
diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c
index c08b315dab93..9300357f2d38 100644
--- a/lib/compress/zstd_compress.c
+++ b/lib/compress/zstd_compress.c
@@ -9,6 +9,14 @@
 
 
 /*-*************************************
+*  Tuning parameters
+***************************************/
+#ifndef ZSTD_CLEVEL_DEFAULT
+#  define ZSTD_CLEVEL_DEFAULT 3
+#endif
+
+
+/*-*************************************
 *  Dependencies
 ***************************************/
 #include <string.h>         /* memset */
@@ -18,26 +26,7 @@
 #define HUF_STATIC_LINKING_ONLY
 #include "huf.h"
 #include "zstd_internal.h"  /* includes zstd.h */
-
-
-/*-*************************************
-*  Debug
-***************************************/
-#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
-#  include <assert.h>
-#else
-#  define assert(condition) ((void)0)
-#endif
-
-#define ZSTD_STATIC_ASSERT(c) { enum { ZSTD_static_assert = 1/(int)(!!(c)) }; }
-
-#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=2)
-#  include <stdio.h>
-   static unsigned g_debugLevel = ZSTD_DEBUG;
-#  define DEBUGLOG(l, ...) if (l<=g_debugLevel) { fprintf(stderr, __FILE__ ": "); fprintf(stderr, __VA_ARGS__); fprintf(stderr, " \n"); }
-#else
-#  define DEBUGLOG(l, ...)      {}    /* disabled */
-#endif
+#include "zstdmt_compress.h"
 
 
 /*-*************************************
@@ -79,6 +68,15 @@ static void ZSTD_resetSeqStore(seqStore_t* ssPtr)
 /*-*************************************
 *  Context memory management
 ***************************************/
+typedef enum { zcss_init=0, zcss_load, zcss_flush } ZSTD_cStreamStage;
+
+struct ZSTD_CDict_s {
+    void* dictBuffer;
+    const void* dictContent;
+    size_t dictContentSize;
+    ZSTD_CCtx* refContext;
+};  /* typedef'd to ZSTD_CDict within "zstd.h" */
+
 struct ZSTD_CCtx_s {
     const BYTE* nextSrc;    /* next block here to continue on current prefix */
     const BYTE* base;       /* All regular indexes relative to this position */
@@ -90,19 +88,21 @@ struct ZSTD_CCtx_s {
     U32   hashLog3;         /* dispatch table : larger == faster, more memory */
     U32   loadedDictEnd;    /* index of end of dictionary */
     U32   forceWindow;      /* force back-references to respect limit of 1<<wLog, even for dictionary */
-    U32   forceRawDict;     /* Force loading dictionary in "content-only" mode (no header analysis) */
     ZSTD_compressionStage_e stage;
     U32   rep[ZSTD_REP_NUM];
     U32   repToConfirm[ZSTD_REP_NUM];
     U32   dictID;
-    ZSTD_parameters params;
+    int   compressionLevel;
+    ZSTD_parameters requestedParams;
+    ZSTD_parameters appliedParams;
     void* workSpace;
     size_t workSpaceSize;
     size_t blockSize;
-    U64 frameContentSize;
+    U64 pledgedSrcSizePlusOne;  /* this way, 0 (default) == unknown */
     U64 consumedSrcSize;
     XXH64_state_t xxhState;
     ZSTD_customMem customMem;
+    size_t staticSize;
 
     seqStore_t seqStore;    /* sequences storage ptrs */
     U32* hashTable;
@@ -115,31 +115,92 @@ struct ZSTD_CCtx_s {
     FSE_CTable* matchlengthCTable;
     FSE_CTable* litlengthCTable;
     unsigned* entropyScratchSpace;
+
+    /* streaming */
+    char*  inBuff;
+    size_t inBuffSize;
+    size_t inToCompress;
+    size_t inBuffPos;
+    size_t inBuffTarget;
+    char*  outBuff;
+    size_t outBuffSize;
+    size_t outBuffContentSize;
+    size_t outBuffFlushedSize;
+    ZSTD_cStreamStage streamStage;
+    U32    frameEnded;
+
+    /* Dictionary */
+    ZSTD_dictMode_e dictMode; /* select restricting dictionary to "rawContent" or "fullDict" only */
+    U32 dictContentByRef;
+    ZSTD_CDict* cdictLocal;
+    const ZSTD_CDict* cdict;
+    const void* prefix;
+    size_t prefixSize;
+
+    /* Multi-threading */
+    U32 nbThreads;
+    ZSTDMT_CCtx* mtctx;
 };
 
+
 ZSTD_CCtx* ZSTD_createCCtx(void)
 {
-    return ZSTD_createCCtx_advanced(defaultCustomMem);
+    return ZSTD_createCCtx_advanced(ZSTD_defaultCMem);
 }
 
 ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem)
 {
     ZSTD_CCtx* cctx;
 
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
 
-    cctx = (ZSTD_CCtx*) ZSTD_malloc(sizeof(ZSTD_CCtx), customMem);
+    cctx = (ZSTD_CCtx*) ZSTD_calloc(sizeof(ZSTD_CCtx), customMem);
     if (!cctx) return NULL;
-    memset(cctx, 0, sizeof(ZSTD_CCtx));
     cctx->customMem = customMem;
+    cctx->compressionLevel = ZSTD_CLEVEL_DEFAULT;
+    ZSTD_STATIC_ASSERT(zcss_init==0);
+    ZSTD_STATIC_ASSERT(ZSTD_CONTENTSIZE_UNKNOWN==(0ULL - 1));
+    return cctx;
+}
+
+ZSTD_CCtx* ZSTD_initStaticCCtx(void *workspace, size_t workspaceSize)
+{
+    ZSTD_CCtx* cctx = (ZSTD_CCtx*) workspace;
+    if (workspaceSize <= sizeof(ZSTD_CCtx)) return NULL;  /* minimum size */
+    if ((size_t)workspace & 7) return NULL;  /* must be 8-aligned */
+    memset(workspace, 0, workspaceSize);   /* may be a bit generous, could memset be smaller ? */
+    cctx->staticSize = workspaceSize;
+    cctx->workSpace = (void*)(cctx+1);
+    cctx->workSpaceSize = workspaceSize - sizeof(ZSTD_CCtx);
+
+    /* entropy space (never moves) */
+    /* note : this code should be shared with resetCCtx, rather than copy/pasted */
+    {   void* ptr = cctx->workSpace;
+        cctx->hufCTable = (HUF_CElt*)ptr;
+        ptr = (char*)cctx->hufCTable + hufCTable_size;
+        cctx->offcodeCTable = (FSE_CTable*) ptr;
+        ptr = (char*)ptr + offcodeCTable_size;
+        cctx->matchlengthCTable = (FSE_CTable*) ptr;
+        ptr = (char*)ptr + matchlengthCTable_size;
+        cctx->litlengthCTable = (FSE_CTable*) ptr;
+        ptr = (char*)ptr + litlengthCTable_size;
+        assert(((size_t)ptr & 3) == 0);   /* ensure correct alignment */
+        cctx->entropyScratchSpace = (unsigned*) ptr;
+    }
+
     return cctx;
 }
 
 size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx)
 {
     if (cctx==NULL) return 0;   /* support free on NULL */
+    if (cctx->staticSize) return ERROR(memory_allocation);   /* not compatible with static CCtx */
     ZSTD_free(cctx->workSpace, cctx->customMem);
+    cctx->workSpace = NULL;
+    ZSTD_freeCDict(cctx->cdictLocal);
+    cctx->cdictLocal = NULL;
+    ZSTDMT_freeCCtx(cctx->mtctx);
+    cctx->mtctx = NULL;
     ZSTD_free(cctx, cctx->customMem);
     return 0;   /* reserved as a potential error code in the future */
 }
@@ -147,46 +208,294 @@ size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx)
 size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx)
 {
     if (cctx==NULL) return 0;   /* support sizeof on NULL */
-    return sizeof(*cctx) + cctx->workSpaceSize;
+    DEBUGLOG(5, "sizeof(*cctx) : %u", (U32)sizeof(*cctx));
+    DEBUGLOG(5, "workSpaceSize : %u", (U32)cctx->workSpaceSize);
+    DEBUGLOG(5, "streaming buffers : %u", (U32)(cctx->outBuffSize + cctx->inBuffSize));
+    DEBUGLOG(5, "inner MTCTX : %u", (U32)ZSTDMT_sizeof_CCtx(cctx->mtctx));
+    return sizeof(*cctx) + cctx->workSpaceSize
+           + ZSTD_sizeof_CDict(cctx->cdictLocal)
+           + cctx->outBuffSize + cctx->inBuffSize
+           + ZSTDMT_sizeof_CCtx(cctx->mtctx);
 }
 
+size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs)
+{
+    return ZSTD_sizeof_CCtx(zcs);  /* same object */
+}
+
+/* private API call, for dictBuilder only */
+const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx) { return &(ctx->seqStore); }
+
+static ZSTD_parameters ZSTD_getParamsFromCCtx(const ZSTD_CCtx* cctx) { return cctx->appliedParams; }
+
+/* older variant; will be deprecated */
 size_t ZSTD_setCCtxParameter(ZSTD_CCtx* cctx, ZSTD_CCtxParameter param, unsigned value)
 {
     switch(param)
     {
     case ZSTD_p_forceWindow : cctx->forceWindow = value>0; cctx->loadedDictEnd = 0; return 0;
-    case ZSTD_p_forceRawDict : cctx->forceRawDict = value>0; return 0;
+    ZSTD_STATIC_ASSERT(ZSTD_dm_auto==0);
+    ZSTD_STATIC_ASSERT(ZSTD_dm_rawContent==1);
+    case ZSTD_p_forceRawDict : cctx->dictMode = (ZSTD_dictMode_e)(value>0); return 0;
     default: return ERROR(parameter_unknown);
     }
 }
 
-const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx)   /* hidden interface */
+
+#define ZSTD_CLEVEL_CUSTOM 999
+static void ZSTD_cLevelToCParams(ZSTD_CCtx* cctx)
 {
-    return &(ctx->seqStore);
+    if (cctx->compressionLevel==ZSTD_CLEVEL_CUSTOM) return;
+    cctx->requestedParams.cParams = ZSTD_getCParams(cctx->compressionLevel,
+                                            cctx->pledgedSrcSizePlusOne-1, 0);
+    cctx->compressionLevel = ZSTD_CLEVEL_CUSTOM;
 }
 
-static ZSTD_parameters ZSTD_getParamsFromCCtx(const ZSTD_CCtx* cctx)
+#define CLAMPCHECK(val,min,max) {                       \
+    if (((val)<(min)) | ((val)>(max))) {                \
+        return ERROR(compressionParameter_outOfBound);  \
+}   }
+
+size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned value)
 {
-    return cctx->params;
+    if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
+
+    switch(param)
+    {
+    case ZSTD_p_compressionLevel :
+        if ((int)value > ZSTD_maxCLevel()) value = ZSTD_maxCLevel();   /* cap max compression level */
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        cctx->compressionLevel = value;
+        return 0;
+
+    case ZSTD_p_windowLog :
+        DEBUGLOG(5, "setting ZSTD_p_windowLog = %u (cdict:%u)",
+                    value, (cctx->cdict!=NULL));
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.windowLog = value;
+        return 0;
+
+    case ZSTD_p_hashLog :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.hashLog = value;
+        return 0;
+
+    case ZSTD_p_chainLog :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.chainLog = value;
+        return 0;
+
+    case ZSTD_p_searchLog :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.searchLog = value;
+        return 0;
+
+    case ZSTD_p_minMatch :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.searchLength = value;
+        return 0;
+
+    case ZSTD_p_targetLength :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.targetLength = value;
+        return 0;
+
+    case ZSTD_p_compressionStrategy :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, (unsigned)ZSTD_fast, (unsigned)ZSTD_btultra);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.strategy = (ZSTD_strategy)value;
+        return 0;
+
+    case ZSTD_p_contentSizeFlag :
+        DEBUGLOG(5, "set content size flag = %u", (value>0));
+        /* Content size written in frame header _when known_ (default:1) */
+        cctx->requestedParams.fParams.contentSizeFlag = value>0;
+        return 0;
+
+    case ZSTD_p_checksumFlag :
+        /* A 32-bits content checksum will be calculated and written at end of frame (default:0) */
+        cctx->requestedParams.fParams.checksumFlag = value>0;
+        return 0;
+
+    case ZSTD_p_dictIDFlag : /* When applicable, dictionary's dictID is provided in frame header (default:1) */
+        DEBUGLOG(5, "set dictIDFlag = %u", (value>0));
+        cctx->requestedParams.fParams.noDictIDFlag = (value==0);
+        return 0;
+
+    /* Dictionary parameters */
+    case ZSTD_p_dictMode :
+        if (cctx->cdict) return ERROR(stage_wrong);  /* must be set before loading */
+        /* restrict dictionary mode, to "rawContent" or "fullDict" only */
+        ZSTD_STATIC_ASSERT((U32)ZSTD_dm_fullDict > (U32)ZSTD_dm_rawContent);
+        if (value > (unsigned)ZSTD_dm_fullDict)
+            return ERROR(compressionParameter_outOfBound);
+        cctx->dictMode = (ZSTD_dictMode_e)value;
+        return 0;
+
+    case ZSTD_p_refDictContent :
+        if (cctx->cdict) return ERROR(stage_wrong);  /* must be set before loading */
+        /* dictionary content will be referenced, instead of copied */
+        cctx->dictContentByRef = value>0;
+        return 0;
+
+    case ZSTD_p_forceMaxWindow :  /* Force back-references to remain < windowSize,
+                                   * even when referencing into Dictionary content
+                                   * default : 0 when using a CDict, 1 when using a Prefix */
+        cctx->forceWindow = value>0;
+        cctx->loadedDictEnd = 0;
+        return 0;
+
+    case ZSTD_p_nbThreads:
+        if (value==0) return 0;
+        DEBUGLOG(5, " setting nbThreads : %u", value);
+#ifndef ZSTD_MULTITHREAD
+        if (value > 1) return ERROR(compressionParameter_unsupported);
+#endif
+        if ((value>1) && (cctx->nbThreads != value)) {
+            if (cctx->staticSize)  /* MT not compatible with static alloc */
+                return ERROR(compressionParameter_unsupported);
+            ZSTDMT_freeCCtx(cctx->mtctx);
+            cctx->nbThreads = 1;
+            cctx->mtctx = ZSTDMT_createCCtx(value);
+            if (cctx->mtctx == NULL) return ERROR(memory_allocation);
+        }
+        cctx->nbThreads = value;
+        return 0;
+
+    case ZSTD_p_jobSize:
+        if (cctx->nbThreads <= 1) return ERROR(compressionParameter_unsupported);
+        assert(cctx->mtctx != NULL);
+        return ZSTDMT_setMTCtxParameter(cctx->mtctx, ZSTDMT_p_sectionSize, value);
+
+    case ZSTD_p_overlapSizeLog:
+        DEBUGLOG(5, " setting overlap with nbThreads == %u", cctx->nbThreads);
+        if (cctx->nbThreads <= 1) return ERROR(compressionParameter_unsupported);
+        assert(cctx->mtctx != NULL);
+        return ZSTDMT_setMTCtxParameter(cctx->mtctx, ZSTDMT_p_overlapSectionLog, value);
+
+    default: return ERROR(parameter_unknown);
+    }
+}
+
+ZSTDLIB_API size_t ZSTD_CCtx_setPledgedSrcSize(ZSTD_CCtx* cctx, unsigned long long pledgedSrcSize)
+{
+    DEBUGLOG(5, " setting pledgedSrcSize to %u", (U32)pledgedSrcSize);
+    if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
+    cctx->pledgedSrcSizePlusOne = pledgedSrcSize+1;
+    return 0;
+}
+
+ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize)
+{
+    if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
+    if (cctx->staticSize) return ERROR(memory_allocation);  /* no malloc for static CCtx */
+    DEBUGLOG(5, "load dictionary of size %u", (U32)dictSize);
+    ZSTD_freeCDict(cctx->cdictLocal);  /* in case one already exists */
+    if (dict==NULL || dictSize==0) {   /* no dictionary mode */
+        cctx->cdictLocal = NULL;
+        cctx->cdict = NULL;
+    } else {
+        ZSTD_compressionParameters const cParams =
+                cctx->compressionLevel == ZSTD_CLEVEL_CUSTOM ?
+                cctx->requestedParams.cParams :
+                ZSTD_getCParams(cctx->compressionLevel, 0, dictSize);
+        cctx->cdictLocal = ZSTD_createCDict_advanced(
+                                dict, dictSize,
+                                cctx->dictContentByRef, cctx->dictMode,
+                                cParams, cctx->customMem);
+        cctx->cdict = cctx->cdictLocal;
+        if (cctx->cdictLocal == NULL)
+            return ERROR(memory_allocation);
+    }
+    return 0;
+}
+
+size_t ZSTD_CCtx_refCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict)
+{
+    if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
+    cctx->cdict = cdict;
+    cctx->prefix = NULL;   /* exclusive */
+    cctx->prefixSize = 0;
+    return 0;
+}
+
+size_t ZSTD_CCtx_refPrefix(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize)
+{
+    if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
+    cctx->cdict = NULL;   /* prefix discards any prior cdict */
+    cctx->prefix = prefix;
+    cctx->prefixSize = prefixSize;
+    return 0;
+}
+
+static void ZSTD_startNewCompression(ZSTD_CCtx* cctx)
+{
+    cctx->streamStage = zcss_init;
+    cctx->pledgedSrcSizePlusOne = 0;
 }
 
+/*! ZSTD_CCtx_reset() :
+ *  Also dumps dictionary */
+void ZSTD_CCtx_reset(ZSTD_CCtx* cctx)
+{
+    ZSTD_startNewCompression(cctx);
+    cctx->cdict = NULL;
+}
 
-/** ZSTD_checkParams() :
-    ensure param values remain within authorized range.
+/** ZSTD_checkCParams() :
+    control CParam values remain within authorized range.
     @return : 0, or an error code if one value is beyond authorized range */
 size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams)
 {
-#   define CLAMPCHECK(val,min,max) { if ((val<min) | (val>max)) return ERROR(compressionParameter_unsupported); }
     CLAMPCHECK(cParams.windowLog, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
     CLAMPCHECK(cParams.chainLog, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
     CLAMPCHECK(cParams.hashLog, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
     CLAMPCHECK(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
     CLAMPCHECK(cParams.searchLength, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
     CLAMPCHECK(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
-    if ((U32)(cParams.strategy) > (U32)ZSTD_btopt2) return ERROR(compressionParameter_unsupported);
+    if ((U32)(cParams.strategy) > (U32)ZSTD_btultra) return ERROR(compressionParameter_unsupported);
     return 0;
 }
 
+/** ZSTD_clampCParams() :
+ *  make CParam values within valid range.
+ *  @return : valid CParams */
+static ZSTD_compressionParameters ZSTD_clampCParams(ZSTD_compressionParameters cParams)
+{
+#   define CLAMP(val,min,max) {      \
+        if (val<min) val=min;        \
+        else if (val>max) val=max;   \
+    }
+    CLAMP(cParams.windowLog, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
+    CLAMP(cParams.chainLog, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
+    CLAMP(cParams.hashLog, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
+    CLAMP(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
+    CLAMP(cParams.searchLength, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
+    CLAMP(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
+    if ((U32)(cParams.strategy) > (U32)ZSTD_btultra) cParams.strategy = ZSTD_btultra;
+    return cParams;
+}
 
 /** ZSTD_cycleLog() :
  *  condition for correct operation : hashLog > 1 */
@@ -196,14 +505,15 @@ static U32 ZSTD_cycleLog(U32 hashLog, ZSTD_strategy strat)
     return hashLog - btScale;
 }
 
-/** ZSTD_adjustCParams() :
+/** ZSTD_adjustCParams_internal() :
     optimize `cPar` for a given input (`srcSize` and `dictSize`).
     mostly downsizing to reduce memory consumption and initialization.
     Both `srcSize` and `dictSize` are optional (use 0 if unknown),
     but if both are 0, no optimization can be done.
     Note : cPar is considered validated at this stage. Use ZSTD_checkParams() to ensure that. */
-ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize)
+ZSTD_compressionParameters ZSTD_adjustCParams_internal(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize)
 {
+    assert(ZSTD_checkCParams(cPar)==0);
     if (srcSize+dictSize == 0) return cPar;   /* no size information available : no adjustment */
 
     /* resize params, to use less memory when necessary */
@@ -223,10 +533,16 @@ ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, u
     return cPar;
 }
 
+ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize)
+{
+    cPar = ZSTD_clampCParams(cPar);
+    return ZSTD_adjustCParams_internal(cPar, srcSize, dictSize);
+}
 
-size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams)
+
+size_t ZSTD_estimateCCtxSize_advanced(ZSTD_compressionParameters cParams)
 {
-    size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << cParams.windowLog);
+    size_t const blockSize = MIN(ZSTD_BLOCKSIZE_MAX, (size_t)1 << cParams.windowLog);
     U32    const divider = (cParams.searchLength==3) ? 3 : 4;
     size_t const maxNbSeq = blockSize / divider;
     size_t const tokenSpace = blockSize + 11*maxNbSeq;
@@ -240,31 +556,64 @@ size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams)
                               + entropyScratchSpace_size;
     size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
 
-    size_t const optSpace = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits))*sizeof(U32)
+    size_t const optBudget = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits))*sizeof(U32)
                           + (ZSTD_OPT_NUM+1)*(sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t));
-    size_t const neededSpace = entropySpace + tableSpace + tokenSpace
-                             + (((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btopt2)) ? optSpace : 0);
+    size_t const optSpace = ((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btultra)) ? optBudget : 0;
+    size_t const neededSpace = entropySpace + tableSpace + tokenSpace + optSpace;
 
+    DEBUGLOG(5, "sizeof(ZSTD_CCtx) : %u", (U32)sizeof(ZSTD_CCtx));
+    DEBUGLOG(5, "estimate workSpace : %u", (U32)neededSpace);
     return sizeof(ZSTD_CCtx) + neededSpace;
 }
 
+size_t ZSTD_estimateCCtxSize(int compressionLevel)
+{
+    ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, 0, 0);
+    return ZSTD_estimateCCtxSize_advanced(cParams);
+}
 
-static U32 ZSTD_equivalentParams(ZSTD_parameters param1, ZSTD_parameters param2)
+size_t ZSTD_estimateCStreamSize_advanced(ZSTD_compressionParameters cParams)
 {
-    return (param1.cParams.hashLog  == param2.cParams.hashLog)
-         & (param1.cParams.chainLog == param2.cParams.chainLog)
-         & (param1.cParams.strategy == param2.cParams.strategy)
-         & ((param1.cParams.searchLength==3) == (param2.cParams.searchLength==3));
+    size_t const CCtxSize = ZSTD_estimateCCtxSize_advanced(cParams);
+    size_t const blockSize = MIN(ZSTD_BLOCKSIZE_MAX, (size_t)1 << cParams.windowLog);
+    size_t const inBuffSize = ((size_t)1 << cParams.windowLog) + blockSize;
+    size_t const outBuffSize = ZSTD_compressBound(blockSize) + 1;
+    size_t const streamingSize = inBuffSize + outBuffSize;
+
+    return CCtxSize + streamingSize;
+}
+
+size_t ZSTD_estimateCStreamSize(int compressionLevel) {
+    ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, 0, 0);
+    return ZSTD_estimateCStreamSize_advanced(cParams);
+}
+
+
+static U32 ZSTD_equivalentParams(ZSTD_compressionParameters cParams1,
+                                 ZSTD_compressionParameters cParams2)
+{
+    U32 bslog1 = MIN(cParams1.windowLog, ZSTD_BLOCKSIZELOG_MAX);
+    U32 bslog2 = MIN(cParams2.windowLog, ZSTD_BLOCKSIZELOG_MAX);
+    return (bslog1 == bslog2)   /* same block size */
+         & (cParams1.hashLog  == cParams2.hashLog)
+         & (cParams1.chainLog == cParams2.chainLog)
+         & (cParams1.strategy == cParams2.strategy)   /* opt parser space */
+         & ((cParams1.searchLength==3) == (cParams2.searchLength==3));  /* hashlog3 space */
 }
 
 /*! ZSTD_continueCCtx() :
-    reuse CCtx without reset (note : requires no dictionary) */
-static size_t ZSTD_continueCCtx(ZSTD_CCtx* cctx, ZSTD_parameters params, U64 frameContentSize)
+ *  reuse CCtx without reset (note : requires no dictionary) */
+static size_t ZSTD_continueCCtx(ZSTD_CCtx* cctx, ZSTD_parameters params, U64 pledgedSrcSize)
 {
     U32 const end = (U32)(cctx->nextSrc - cctx->base);
-    cctx->params = params;
-    cctx->frameContentSize = frameContentSize;
+    DEBUGLOG(5, "continue mode");
+    cctx->appliedParams = params;
+    cctx->pledgedSrcSizePlusOne = pledgedSrcSize+1;
     cctx->consumedSrcSize = 0;
+    if (pledgedSrcSize == ZSTD_CONTENTSIZE_UNKNOWN)
+        cctx->appliedParams.fParams.contentSizeFlag = 0;
+    DEBUGLOG(5, "pledged content size : %u ; flag : %u",
+        (U32)pledgedSrcSize, cctx->appliedParams.fParams.contentSizeFlag);
     cctx->lowLimit = end;
     cctx->dictLimit = end;
     cctx->nextToUpdate = end+1;
@@ -277,30 +626,39 @@ static size_t ZSTD_continueCCtx(ZSTD_CCtx* cctx, ZSTD_parameters params, U64 fra
     return 0;
 }
 
-typedef enum { ZSTDcrp_continue, ZSTDcrp_noMemset, ZSTDcrp_fullReset } ZSTD_compResetPolicy_e;
+typedef enum { ZSTDcrp_continue, ZSTDcrp_noMemset } ZSTD_compResetPolicy_e;
+typedef enum { ZSTDb_not_buffered, ZSTDb_buffered } ZSTD_buffered_policy_e;
 
 /*! ZSTD_resetCCtx_internal() :
-    note : `params` must be validated */
-static size_t ZSTD_resetCCtx_internal (ZSTD_CCtx* zc,
-                                       ZSTD_parameters params, U64 frameContentSize,
-                                       ZSTD_compResetPolicy_e const crp)
+    note : `params` are assumed fully validated at this stage */
+static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
+                                      ZSTD_parameters params, U64 pledgedSrcSize,
+                                      ZSTD_compResetPolicy_e const crp,
+                                      ZSTD_buffered_policy_e const zbuff)
 {
-    if (crp == ZSTDcrp_continue)
-        if (ZSTD_equivalentParams(params, zc->params)) {
+    assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
+
+    if (crp == ZSTDcrp_continue) {
+        if (ZSTD_equivalentParams(params.cParams, zc->appliedParams.cParams)) {
+            DEBUGLOG(5, "ZSTD_equivalentParams()==1");
             zc->fseCTables_ready = 0;
             zc->hufCTable_repeatMode = HUF_repeat_none;
-            return ZSTD_continueCCtx(zc, params, frameContentSize);
-        }
+            return ZSTD_continueCCtx(zc, params, pledgedSrcSize);
+    }   }
 
-    {   size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << params.cParams.windowLog);
+    {   size_t const blockSize = MIN(ZSTD_BLOCKSIZE_MAX, (size_t)1 << params.cParams.windowLog);
         U32    const divider = (params.cParams.searchLength==3) ? 3 : 4;
         size_t const maxNbSeq = blockSize / divider;
         size_t const tokenSpace = blockSize + 11*maxNbSeq;
-        size_t const chainSize = (params.cParams.strategy == ZSTD_fast) ? 0 : (1 << params.cParams.chainLog);
+        size_t const chainSize = (params.cParams.strategy == ZSTD_fast) ?
+                                0 : (1 << params.cParams.chainLog);
         size_t const hSize = ((size_t)1) << params.cParams.hashLog;
-        U32    const hashLog3 = (params.cParams.searchLength>3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, params.cParams.windowLog);
+        U32    const hashLog3 = (params.cParams.searchLength>3) ?
+                                0 : MIN(ZSTD_HASHLOG3_MAX, params.cParams.windowLog);
         size_t const h3Size = ((size_t)1) << hashLog3;
         size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
+        size_t const buffOutSize = (zbuff==ZSTDb_buffered) ? ZSTD_compressBound(blockSize)+1 : 0;
+        size_t const buffInSize = (zbuff==ZSTDb_buffered) ? ((size_t)1 << params.cParams.windowLog) + blockSize : 0;
         void* ptr;
 
         /* Check if workSpace is large enough, alloc a new one if needed */
@@ -309,9 +667,20 @@ static size_t ZSTD_resetCCtx_internal (ZSTD_CCtx* zc,
                                   + entropyScratchSpace_size;
             size_t const optPotentialSpace = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits)) * sizeof(U32)
                                   + (ZSTD_OPT_NUM+1) * (sizeof(ZSTD_match_t)+sizeof(ZSTD_optimal_t));
-            size_t const optSpace = ((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btopt2)) ? optPotentialSpace : 0;
-            size_t const neededSpace = entropySpace + optSpace + tableSpace + tokenSpace;
-            if (zc->workSpaceSize < neededSpace) {
+            size_t const optSpace = ( (params.cParams.strategy == ZSTD_btopt)
+                                    || (params.cParams.strategy == ZSTD_btultra)) ?
+                                    optPotentialSpace : 0;
+            size_t const bufferSpace = buffInSize + buffOutSize;
+            size_t const neededSpace = entropySpace + optSpace + tableSpace
+                                     + tokenSpace + bufferSpace;
+
+            if (zc->workSpaceSize < neededSpace) {  /* too small : resize /*/
+                DEBUGLOG(5, "Need to update workSpaceSize from %uK to %uK \n",
+                            (unsigned)zc->workSpaceSize>>10,
+                            (unsigned)neededSpace>>10);
+                /* static cctx : no resize, error out */
+                if (zc->staticSize) return ERROR(memory_allocation);
+
                 zc->workSpaceSize = 0;
                 ZSTD_free(zc->workSpace, zc->customMem);
                 zc->workSpace = ZSTD_malloc(neededSpace, zc->customMem);
@@ -333,10 +702,14 @@ static size_t ZSTD_resetCCtx_internal (ZSTD_CCtx* zc,
         }   }
 
         /* init params */
-        zc->params = params;
-        zc->blockSize = blockSize;
-        zc->frameContentSize = frameContentSize;
+        zc->appliedParams = params;
+        zc->pledgedSrcSizePlusOne = pledgedSrcSize+1;
         zc->consumedSrcSize = 0;
+        if (pledgedSrcSize == ZSTD_CONTENTSIZE_UNKNOWN)
+            zc->appliedParams.fParams.contentSizeFlag = 0;
+        DEBUGLOG(5, "pledged content size : %u ; flag : %u",
+            (U32)pledgedSrcSize, zc->appliedParams.fParams.contentSizeFlag);
+        zc->blockSize = blockSize;
 
         XXH64_reset(&zc->xxhState, 0);
         zc->stage = ZSTDcs_init;
@@ -363,7 +736,8 @@ static size_t ZSTD_resetCCtx_internal (ZSTD_CCtx* zc,
         ptr = (char*)zc->entropyScratchSpace + entropyScratchSpace_size;
 
         /* opt parser space */
-        if ((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btopt2)) {
+        if ((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btultra)) {
+            DEBUGLOG(5, "reserving optimal parser space");
             assert(((size_t)ptr & 3) == 0);  /* ensure ptr is properly aligned */
             zc->seqStore.litFreq = (U32*)ptr;
             zc->seqStore.litLengthFreq = zc->seqStore.litFreq + (1<<Litbits);
@@ -391,6 +765,13 @@ static size_t ZSTD_resetCCtx_internal (ZSTD_CCtx* zc,
         zc->seqStore.mlCode = zc->seqStore.llCode + maxNbSeq;
         zc->seqStore.ofCode = zc->seqStore.mlCode + maxNbSeq;
         zc->seqStore.litStart = zc->seqStore.ofCode + maxNbSeq;
+        ptr = zc->seqStore.litStart + blockSize;
+
+        /* buffers */
+        zc->inBuffSize = buffInSize;
+        zc->inBuff = (char*)ptr;
+        zc->outBuffSize = buffOutSize;
+        zc->outBuff = zc->inBuff + buffInSize;
 
         return 0;
     }
@@ -411,21 +792,25 @@ void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx) {
  *  Only works during stage ZSTDcs_init (i.e. after creation, but before first call to ZSTD_compressContinue()).
  *  pledgedSrcSize=0 means "empty" if fParams.contentSizeFlag=1
  *  @return : 0, or an error code */
-size_t ZSTD_copyCCtx_internal(ZSTD_CCtx* dstCCtx, const ZSTD_CCtx* srcCCtx,
-                              ZSTD_frameParameters fParams, unsigned long long pledgedSrcSize)
+static size_t ZSTD_copyCCtx_internal(ZSTD_CCtx* dstCCtx,
+                            const ZSTD_CCtx* srcCCtx,
+                            ZSTD_frameParameters fParams,
+                            unsigned long long pledgedSrcSize,
+                            ZSTD_buffered_policy_e zbuff)
 {
+    DEBUGLOG(5, "ZSTD_copyCCtx_internal");
     if (srcCCtx->stage!=ZSTDcs_init) return ERROR(stage_wrong);
 
     memcpy(&dstCCtx->customMem, &srcCCtx->customMem, sizeof(ZSTD_customMem));
-    {   ZSTD_parameters params = srcCCtx->params;
+    {   ZSTD_parameters params = srcCCtx->appliedParams;
         params.fParams = fParams;
-        DEBUGLOG(5, "ZSTD_resetCCtx_internal : dictIDFlag : %u \n", !fParams.noDictIDFlag);
-        ZSTD_resetCCtx_internal(dstCCtx, params, pledgedSrcSize, ZSTDcrp_noMemset);
+        ZSTD_resetCCtx_internal(dstCCtx, params, pledgedSrcSize,
+                                ZSTDcrp_noMemset, zbuff);
     }
 
     /* copy tables */
-    {   size_t const chainSize = (srcCCtx->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << srcCCtx->params.cParams.chainLog);
-        size_t const hSize =  (size_t)1 << srcCCtx->params.cParams.hashLog;
+    {   size_t const chainSize = (srcCCtx->appliedParams.cParams.strategy == ZSTD_fast) ? 0 : (1 << srcCCtx->appliedParams.cParams.chainLog);
+        size_t const hSize =  (size_t)1 << srcCCtx->appliedParams.cParams.hashLog;
         size_t const h3Size = (size_t)1 << srcCCtx->hashLog3;
         size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
         assert((U32*)dstCCtx->chainTable == (U32*)dstCCtx->hashTable + hSize);  /* chainTable must follow hashTable */
@@ -467,9 +852,11 @@ size_t ZSTD_copyCCtx_internal(ZSTD_CCtx* dstCCtx, const ZSTD_CCtx* srcCCtx,
 size_t ZSTD_copyCCtx(ZSTD_CCtx* dstCCtx, const ZSTD_CCtx* srcCCtx, unsigned long long pledgedSrcSize)
 {
     ZSTD_frameParameters fParams = { 1 /*content*/, 0 /*checksum*/, 0 /*noDictID*/ };
+    ZSTD_buffered_policy_e const zbuff = (ZSTD_buffered_policy_e)(srcCCtx->inBuffSize>0);
+    ZSTD_STATIC_ASSERT((U32)ZSTDb_buffered==1);
     fParams.contentSizeFlag = pledgedSrcSize>0;
 
-    return ZSTD_copyCCtx_internal(dstCCtx, srcCCtx, fParams, pledgedSrcSize);
+    return ZSTD_copyCCtx_internal(dstCCtx, srcCCtx, fParams, pledgedSrcSize, zbuff);
 }
 
 
@@ -488,10 +875,10 @@ static void ZSTD_reduceTable (U32* const table, U32 const size, U32 const reduce
 *   rescale all indexes to avoid future overflow (indexes are U32) */
 static void ZSTD_reduceIndex (ZSTD_CCtx* zc, const U32 reducerValue)
 {
-    { U32 const hSize = 1 << zc->params.cParams.hashLog;
+    { U32 const hSize = 1 << zc->appliedParams.cParams.hashLog;
       ZSTD_reduceTable(zc->hashTable, hSize, reducerValue); }
 
-    { U32 const chainSize = (zc->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << zc->params.cParams.chainLog);
+    { U32 const chainSize = (zc->appliedParams.cParams.strategy == ZSTD_fast) ? 0 : (1 << zc->appliedParams.cParams.chainLog);
       ZSTD_reduceTable(zc->chainTable, chainSize, reducerValue); }
 
     { U32 const h3Size = (zc->hashLog3) ? 1 << zc->hashLog3 : 0;
@@ -529,10 +916,11 @@ static size_t ZSTD_noCompressLiterals (void* dst, size_t dstCapacity, const void
         case 2: /* 2 - 2 - 12 */
             MEM_writeLE16(ostart, (U16)((U32)set_basic + (1<<2) + (srcSize<<4)));
             break;
-        default:   /*note : should not be necessary : flSize is within {1,2,3} */
         case 3: /* 2 - 2 - 20 */
             MEM_writeLE32(ostart, (U32)((U32)set_basic + (3<<2) + (srcSize<<4)));
             break;
+        default:   /* not necessary : flSize is {1,2,3} */
+            assert(0);
     }
 
     memcpy(ostart + flSize, src, srcSize);
@@ -554,10 +942,11 @@ static size_t ZSTD_compressRleLiteralsBlock (void* dst, size_t dstCapacity, cons
         case 2: /* 2 - 2 - 12 */
             MEM_writeLE16(ostart, (U16)((U32)set_rle + (1<<2) + (srcSize<<4)));
             break;
-        default:   /*note : should not be necessary : flSize is necessarily within {1,2,3} */
         case 3: /* 2 - 2 - 20 */
             MEM_writeLE32(ostart, (U32)((U32)set_rle + (3<<2) + (srcSize<<4)));
             break;
+        default:   /* not necessary : flSize is {1,2,3} */
+            assert(0);
     }
 
     ostart[flSize] = *(const BYTE*)src;
@@ -587,7 +976,7 @@ static size_t ZSTD_compressLiterals (ZSTD_CCtx* zc,
 
     if (dstCapacity < lhSize+1) return ERROR(dstSize_tooSmall);   /* not enough space for compression */
     {   HUF_repeat repeat = zc->hufCTable_repeatMode;
-        int const preferRepeat = zc->params.cParams.strategy < ZSTD_lazy ? srcSize <= 1024 : 0;
+        int const preferRepeat = zc->appliedParams.cParams.strategy < ZSTD_lazy ? srcSize <= 1024 : 0;
         if (repeat == HUF_repeat_valid && lhSize == 3) singleStream = 1;
         cLitSize = singleStream ? HUF_compress1X_repeat(ostart+lhSize, dstCapacity-lhSize, src, srcSize, 255, 11,
                                       zc->entropyScratchSpace, entropyScratchSpace_size, zc->hufCTable, &repeat, preferRepeat)
@@ -619,13 +1008,14 @@ static size_t ZSTD_compressLiterals (ZSTD_CCtx* zc,
             MEM_writeLE32(ostart, lhc);
             break;
         }
-    default:   /* should not be necessary, lhSize is only {3,4,5} */
     case 5: /* 2 - 2 - 18 - 18 */
         {   U32 const lhc = hType + (3 << 2) + ((U32)srcSize<<4) + ((U32)cLitSize<<22);
             MEM_writeLE32(ostart, lhc);
             ostart[4] = (BYTE)(cLitSize >> 10);
             break;
         }
+    default:   /* not possible : lhSize is {3,4,5} */
+        assert(0);
     }
     return lhSize+cLitSize;
 }
@@ -676,7 +1066,7 @@ MEM_STATIC size_t ZSTD_compressSequences (ZSTD_CCtx* zc,
                               void* dst, size_t dstCapacity,
                               size_t srcSize)
 {
-    const int longOffsets = zc->params.cParams.windowLog > STREAM_ACCUMULATOR_MIN;
+    const int longOffsets = zc->appliedParams.cParams.windowLog > STREAM_ACCUMULATOR_MIN;
     const seqStore_t* seqStorePtr = &(zc->seqStore);
     U32 count[MaxSeq+1];
     S16 norm[MaxSeq+1];
@@ -881,12 +1271,6 @@ _check_compressibility:
     return op - ostart;
 }
 
-#if 0 /* for debug */
-#  define STORESEQ_DEBUG
-#include <stdio.h>   /* fprintf */
-U32 g_startDebug = 0;
-const BYTE* g_start = NULL;
-#endif
 
 /*! ZSTD_storeSeq() :
     Store a sequence (literal length, literals, offset code and match length code) into seqStore_t.
@@ -895,16 +1279,16 @@ const BYTE* g_start = NULL;
 */
 MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const void* literals, U32 offsetCode, size_t matchCode)
 {
-#ifdef STORESEQ_DEBUG
-    if (g_startDebug) {
-        const U32 pos = (U32)((const BYTE*)literals - g_start);
-        if (g_start==NULL) g_start = (const BYTE*)literals;
-        if ((pos > 1895000) && (pos < 1895300))
-            DEBUGLOG(5, "Cpos %6u :%5u literals & match %3u bytes at distance %6u \n",
-                   pos, (U32)litLength, (U32)matchCode+MINMATCH, (U32)offsetCode);
-    }
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG >= 6)
+    static const BYTE* g_start = NULL;
+    U32 const pos = (U32)((const BYTE*)literals - g_start);
+    if (g_start==NULL) g_start = (const BYTE*)literals;
+    if ((pos > 0) && (pos < 1000000000))
+        DEBUGLOG(6, "Cpos %6u :%5u literals & match %3u bytes at distance %6u",
+               pos, (U32)litLength, (U32)matchCode+MINMATCH, (U32)offsetCode);
 #endif
     /* copy Literals */
+    assert(seqStorePtr->lit + litLength <= seqStorePtr->litStart + 128 KB);
     ZSTD_wildcopy(seqStorePtr->lit, literals, litLength);
     seqStorePtr->lit += litLength;
 
@@ -1078,7 +1462,7 @@ static size_t ZSTD_hashPtr(const void* p, U32 hBits, U32 mls)
 static void ZSTD_fillHashTable (ZSTD_CCtx* zc, const void* end, const U32 mls)
 {
     U32* const hashTable = zc->hashTable;
-    U32  const hBits = zc->params.cParams.hashLog;
+    U32  const hBits = zc->appliedParams.cParams.hashLog;
     const BYTE* const base = zc->base;
     const BYTE* ip = base + zc->nextToUpdate;
     const BYTE* const iend = ((const BYTE*)end) - HASH_READ_SIZE;
@@ -1097,7 +1481,7 @@ void ZSTD_compressBlock_fast_generic(ZSTD_CCtx* cctx,
                                const U32 mls)
 {
     U32* const hashTable = cctx->hashTable;
-    U32  const hBits = cctx->params.cParams.hashLog;
+    U32  const hBits = cctx->appliedParams.cParams.hashLog;
     seqStore_t* seqStorePtr = &(cctx->seqStore);
     const BYTE* const base = cctx->base;
     const BYTE* const istart = (const BYTE*)src;
@@ -1182,7 +1566,7 @@ void ZSTD_compressBlock_fast_generic(ZSTD_CCtx* cctx,
 static void ZSTD_compressBlock_fast(ZSTD_CCtx* ctx,
                        const void* src, size_t srcSize)
 {
-    const U32 mls = ctx->params.cParams.searchLength;
+    const U32 mls = ctx->appliedParams.cParams.searchLength;
     switch(mls)
     {
     default: /* includes case 3 */
@@ -1203,7 +1587,7 @@ static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx* ctx,
                                  const U32 mls)
 {
     U32* hashTable = ctx->hashTable;
-    const U32 hBits = ctx->params.cParams.hashLog;
+    const U32 hBits = ctx->appliedParams.cParams.hashLog;
     seqStore_t* seqStorePtr = &(ctx->seqStore);
     const BYTE* const base = ctx->base;
     const BYTE* const dictBase = ctx->dictBase;
@@ -1296,7 +1680,7 @@ static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx* ctx,
 static void ZSTD_compressBlock_fast_extDict(ZSTD_CCtx* ctx,
                          const void* src, size_t srcSize)
 {
-    U32 const mls = ctx->params.cParams.searchLength;
+    U32 const mls = ctx->appliedParams.cParams.searchLength;
     switch(mls)
     {
     default: /* includes case 3 */
@@ -1318,9 +1702,9 @@ static void ZSTD_compressBlock_fast_extDict(ZSTD_CCtx* ctx,
 static void ZSTD_fillDoubleHashTable (ZSTD_CCtx* cctx, const void* end, const U32 mls)
 {
     U32* const hashLarge = cctx->hashTable;
-    U32  const hBitsL = cctx->params.cParams.hashLog;
+    U32  const hBitsL = cctx->appliedParams.cParams.hashLog;
     U32* const hashSmall = cctx->chainTable;
-    U32  const hBitsS = cctx->params.cParams.chainLog;
+    U32  const hBitsS = cctx->appliedParams.cParams.chainLog;
     const BYTE* const base = cctx->base;
     const BYTE* ip = base + cctx->nextToUpdate;
     const BYTE* const iend = ((const BYTE*)end) - HASH_READ_SIZE;
@@ -1340,9 +1724,9 @@ void ZSTD_compressBlock_doubleFast_generic(ZSTD_CCtx* cctx,
                                  const U32 mls)
 {
     U32* const hashLong = cctx->hashTable;
-    const U32 hBitsL = cctx->params.cParams.hashLog;
+    const U32 hBitsL = cctx->appliedParams.cParams.hashLog;
     U32* const hashSmall = cctx->chainTable;
-    const U32 hBitsS = cctx->params.cParams.chainLog;
+    const U32 hBitsS = cctx->appliedParams.cParams.chainLog;
     seqStore_t* seqStorePtr = &(cctx->seqStore);
     const BYTE* const base = cctx->base;
     const BYTE* const istart = (const BYTE*)src;
@@ -1452,7 +1836,7 @@ void ZSTD_compressBlock_doubleFast_generic(ZSTD_CCtx* cctx,
 
 static void ZSTD_compressBlock_doubleFast(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
 {
-    const U32 mls = ctx->params.cParams.searchLength;
+    const U32 mls = ctx->appliedParams.cParams.searchLength;
     switch(mls)
     {
     default: /* includes case 3 */
@@ -1473,9 +1857,9 @@ static void ZSTD_compressBlock_doubleFast_extDict_generic(ZSTD_CCtx* ctx,
                                  const U32 mls)
 {
     U32* const hashLong = ctx->hashTable;
-    U32  const hBitsL = ctx->params.cParams.hashLog;
+    U32  const hBitsL = ctx->appliedParams.cParams.hashLog;
     U32* const hashSmall = ctx->chainTable;
-    U32  const hBitsS = ctx->params.cParams.chainLog;
+    U32  const hBitsS = ctx->appliedParams.cParams.chainLog;
     seqStore_t* seqStorePtr = &(ctx->seqStore);
     const BYTE* const base = ctx->base;
     const BYTE* const dictBase = ctx->dictBase;
@@ -1602,7 +1986,7 @@ static void ZSTD_compressBlock_doubleFast_extDict_generic(ZSTD_CCtx* ctx,
 static void ZSTD_compressBlock_doubleFast_extDict(ZSTD_CCtx* ctx,
                          const void* src, size_t srcSize)
 {
-    U32 const mls = ctx->params.cParams.searchLength;
+    U32 const mls = ctx->appliedParams.cParams.searchLength;
     switch(mls)
     {
     default: /* includes case 3 */
@@ -1628,10 +2012,10 @@ static U32 ZSTD_insertBt1(ZSTD_CCtx* zc, const BYTE* const ip, const U32 mls, co
                           U32 extDict)
 {
     U32*   const hashTable = zc->hashTable;
-    U32    const hashLog = zc->params.cParams.hashLog;
+    U32    const hashLog = zc->appliedParams.cParams.hashLog;
     size_t const h  = ZSTD_hashPtr(ip, hashLog, mls);
     U32*   const bt = zc->chainTable;
-    U32    const btLog  = zc->params.cParams.chainLog - 1;
+    U32    const btLog  = zc->appliedParams.cParams.chainLog - 1;
     U32    const btMask = (1 << btLog) - 1;
     U32 matchIndex = hashTable[h];
     size_t commonLengthSmaller=0, commonLengthLarger=0;
@@ -1733,10 +2117,10 @@ static size_t ZSTD_insertBtAndFindBestMatch (
                         U32 extDict)
 {
     U32*   const hashTable = zc->hashTable;
-    U32    const hashLog = zc->params.cParams.hashLog;
+    U32    const hashLog = zc->appliedParams.cParams.hashLog;
     size_t const h  = ZSTD_hashPtr(ip, hashLog, mls);
     U32*   const bt = zc->chainTable;
-    U32    const btLog  = zc->params.cParams.chainLog - 1;
+    U32    const btLog  = zc->appliedParams.cParams.chainLog - 1;
     U32    const btMask = (1 << btLog) - 1;
     U32 matchIndex  = hashTable[h];
     size_t commonLengthSmaller=0, commonLengthLarger=0;
@@ -1896,9 +2280,9 @@ FORCE_INLINE
 U32 ZSTD_insertAndFindFirstIndex (ZSTD_CCtx* zc, const BYTE* ip, U32 mls)
 {
     U32* const hashTable  = zc->hashTable;
-    const U32 hashLog = zc->params.cParams.hashLog;
+    const U32 hashLog = zc->appliedParams.cParams.hashLog;
     U32* const chainTable = zc->chainTable;
-    const U32 chainMask = (1 << zc->params.cParams.chainLog) - 1;
+    const U32 chainMask = (1 << zc->appliedParams.cParams.chainLog) - 1;
     const BYTE* const base = zc->base;
     const U32 target = (U32)(ip - base);
     U32 idx = zc->nextToUpdate;
@@ -1915,8 +2299,8 @@ U32 ZSTD_insertAndFindFirstIndex (ZSTD_CCtx* zc, const BYTE* ip, U32 mls)
 }
 
 
-
-FORCE_INLINE /* inlining is important to hardwire a hot branch (template emulation) */
+/* inlining is important to hardwire a hot branch (template emulation) */
+FORCE_INLINE
 size_t ZSTD_HcFindBestMatch_generic (
                         ZSTD_CCtx* zc,   /* Index table will be updated */
                         const BYTE* const ip, const BYTE* const iLimit,
@@ -1924,7 +2308,7 @@ size_t ZSTD_HcFindBestMatch_generic (
                         const U32 maxNbAttempts, const U32 mls, const U32 extDict)
 {
     U32* const chainTable = zc->chainTable;
-    const U32 chainSize = (1 << zc->params.cParams.chainLog);
+    const U32 chainSize = (1 << zc->appliedParams.cParams.chainLog);
     const U32 chainMask = chainSize-1;
     const BYTE* const base = zc->base;
     const BYTE* const dictBase = zc->dictBase;
@@ -2018,8 +2402,8 @@ void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx* ctx,
     const BYTE* const ilimit = iend - 8;
     const BYTE* const base = ctx->base + ctx->dictLimit;
 
-    U32 const maxSearches = 1 << ctx->params.cParams.searchLog;
-    U32 const mls = ctx->params.cParams.searchLength;
+    U32 const maxSearches = 1 << ctx->appliedParams.cParams.searchLog;
+    U32 const mls = ctx->appliedParams.cParams.searchLength;
 
     typedef size_t (*searchMax_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
                         size_t* offsetPtr,
@@ -2101,15 +2485,19 @@ void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx* ctx,
             break;  /* nothing found : store previous solution */
         }
 
+        /* NOTE:
+         * start[-offset+ZSTD_REP_MOVE-1] is undefined behavior.
+         * (-offset+ZSTD_REP_MOVE-1) is unsigned, and is added to start, which
+         * overflows the pointer, which is undefined behavior.
+         */
         /* catch up */
         if (offset) {
             while ( (start > anchor)
                  && (start > base+offset-ZSTD_REP_MOVE)
-                 && (start[-1] == start[-1-offset+ZSTD_REP_MOVE]) )  /* only search for offset within prefix */
+                 && (start[-1] == (start-offset+ZSTD_REP_MOVE)[-1]) )  /* only search for offset within prefix */
                 { start--; matchLength++; }
             offset_2 = offset_1; offset_1 = (U32)(offset - ZSTD_REP_MOVE);
         }
-
         /* store sequence */
 _storeSequence:
         {   size_t const litLength = start - anchor;
@@ -2182,8 +2570,8 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
     const BYTE* const dictEnd  = dictBase + dictLimit;
     const BYTE* const dictStart  = dictBase + ctx->lowLimit;
 
-    const U32 maxSearches = 1 << ctx->params.cParams.searchLog;
-    const U32 mls = ctx->params.cParams.searchLength;
+    const U32 maxSearches = 1 << ctx->appliedParams.cParams.searchLog;
+    const U32 mls = ctx->appliedParams.cParams.searchLength;
 
     typedef size_t (*searchMax_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
                         size_t* offsetPtr,
@@ -2370,7 +2758,7 @@ static void ZSTD_compressBlock_btopt(ZSTD_CCtx* ctx, const void* src, size_t src
 #endif
 }
 
-static void ZSTD_compressBlock_btopt2(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
+static void ZSTD_compressBlock_btultra(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
 {
 #ifdef ZSTD_OPT_H_91842398743
     ZSTD_compressBlock_opt_generic(ctx, src, srcSize, 1);
@@ -2390,7 +2778,7 @@ static void ZSTD_compressBlock_btopt_extDict(ZSTD_CCtx* ctx, const void* src, si
 #endif
 }
 
-static void ZSTD_compressBlock_btopt2_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
+static void ZSTD_compressBlock_btultra_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
 {
 #ifdef ZSTD_OPT_H_91842398743
     ZSTD_compressBlock_opt_extDict_generic(ctx, src, srcSize, 1);
@@ -2401,26 +2789,32 @@ static void ZSTD_compressBlock_btopt2_extDict(ZSTD_CCtx* ctx, const void* src, s
 }
 
 
+/* ZSTD_selectBlockCompressor() :
+ * assumption : strat is a valid strategy */
 typedef void (*ZSTD_blockCompressor) (ZSTD_CCtx* ctx, const void* src, size_t srcSize);
-
 static ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, int extDict)
 {
-    static const ZSTD_blockCompressor blockCompressor[2][8] = {
-        { ZSTD_compressBlock_fast, ZSTD_compressBlock_doubleFast, ZSTD_compressBlock_greedy,
+    static const ZSTD_blockCompressor blockCompressor[2][(unsigned)ZSTD_btultra+1] = {
+        { ZSTD_compressBlock_fast  /* default for 0 */,
+          ZSTD_compressBlock_fast, ZSTD_compressBlock_doubleFast, ZSTD_compressBlock_greedy,
           ZSTD_compressBlock_lazy, ZSTD_compressBlock_lazy2, ZSTD_compressBlock_btlazy2,
-          ZSTD_compressBlock_btopt, ZSTD_compressBlock_btopt2 },
-        { ZSTD_compressBlock_fast_extDict, ZSTD_compressBlock_doubleFast_extDict, ZSTD_compressBlock_greedy_extDict,
+          ZSTD_compressBlock_btopt, ZSTD_compressBlock_btultra },
+        { ZSTD_compressBlock_fast_extDict  /* default for 0 */,
+          ZSTD_compressBlock_fast_extDict, ZSTD_compressBlock_doubleFast_extDict, ZSTD_compressBlock_greedy_extDict,
           ZSTD_compressBlock_lazy_extDict,ZSTD_compressBlock_lazy2_extDict, ZSTD_compressBlock_btlazy2_extDict,
-          ZSTD_compressBlock_btopt_extDict, ZSTD_compressBlock_btopt2_extDict }
+          ZSTD_compressBlock_btopt_extDict, ZSTD_compressBlock_btultra_extDict }
     };
+    ZSTD_STATIC_ASSERT((unsigned)ZSTD_fast == 1);
+    assert((U32)strat >= (U32)ZSTD_fast);
+    assert((U32)strat <= (U32)ZSTD_btultra);
 
-    return blockCompressor[extDict][(U32)strat];
+    return blockCompressor[extDict!=0][(U32)strat];
 }
 
 
 static size_t ZSTD_compressBlock_internal(ZSTD_CCtx* zc, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
 {
-    ZSTD_blockCompressor const blockCompressor = ZSTD_selectBlockCompressor(zc->params.cParams.strategy, zc->lowLimit < zc->dictLimit);
+    ZSTD_blockCompressor const blockCompressor = ZSTD_selectBlockCompressor(zc->appliedParams.cParams.strategy, zc->lowLimit < zc->dictLimit);
     const BYTE* const base = zc->base;
     const BYTE* const istart = (const BYTE*)src;
     const U32 current = (U32)(istart-base);
@@ -2433,14 +2827,14 @@ static size_t ZSTD_compressBlock_internal(ZSTD_CCtx* zc, void* dst, size_t dstCa
 }
 
 
-/*! ZSTD_compress_generic() :
+/*! ZSTD_compress_frameChunk() :
 *   Compress a chunk of data into one or multiple blocks.
 *   All blocks will be terminated, all input will be consumed.
 *   Function will issue an error if there is not enough `dstCapacity` to hold the compressed content.
 *   Frame is supposed already started (header already produced)
 *   @return : compressed size, or an error code
 */
-static size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
+static size_t ZSTD_compress_frameChunk (ZSTD_CCtx* cctx,
                                      void* dst, size_t dstCapacity,
                                const void* src, size_t srcSize,
                                      U32 lastFrameChunk)
@@ -2450,9 +2844,9 @@ static size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
     const BYTE* ip = (const BYTE*)src;
     BYTE* const ostart = (BYTE*)dst;
     BYTE* op = ostart;
-    U32 const maxDist = 1 << cctx->params.cParams.windowLog;
+    U32 const maxDist = 1 << cctx->appliedParams.cParams.windowLog;
 
-    if (cctx->params.fParams.checksumFlag && srcSize)
+    if (cctx->appliedParams.fParams.checksumFlag && srcSize)
         XXH64_update(&cctx->xxhState, src, srcSize);
 
     while (remaining) {
@@ -2465,9 +2859,9 @@ static size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
 
         /* preemptive overflow correction */
         if (cctx->lowLimit > (3U<<29)) {
-            U32 const cycleMask = (1 << ZSTD_cycleLog(cctx->params.cParams.hashLog, cctx->params.cParams.strategy)) - 1;
+            U32 const cycleMask = (1 << ZSTD_cycleLog(cctx->appliedParams.cParams.hashLog, cctx->appliedParams.cParams.strategy)) - 1;
             U32 const current = (U32)(ip - cctx->base);
-            U32 const newCurrent = (current & cycleMask) + (1 << cctx->params.cParams.windowLog);
+            U32 const newCurrent = (current & cycleMask) + (1 << cctx->appliedParams.cParams.windowLog);
             U32 const correction = current - newCurrent;
             ZSTD_STATIC_ASSERT(ZSTD_WINDOWLOG_MAX_64 <= 30);
             ZSTD_reduceIndex(cctx, correction);
@@ -2522,22 +2916,20 @@ static size_t ZSTD_writeFrameHeader(void* dst, size_t dstCapacity,
     U32   const singleSegment = params.fParams.contentSizeFlag && (windowSize >= pledgedSrcSize);
     BYTE  const windowLogByte = (BYTE)((params.cParams.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN) << 3);
     U32   const fcsCode = params.fParams.contentSizeFlag ?
-                     (pledgedSrcSize>=256) + (pledgedSrcSize>=65536+256) + (pledgedSrcSize>=0xFFFFFFFFU) :   /* 0-3 */
-                      0;
+                     (pledgedSrcSize>=256) + (pledgedSrcSize>=65536+256) + (pledgedSrcSize>=0xFFFFFFFFU) : 0;  /* 0-3 */
     BYTE  const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag<<2) + (singleSegment<<5) + (fcsCode<<6) );
     size_t pos;
 
     if (dstCapacity < ZSTD_frameHeaderSize_max) return ERROR(dstSize_tooSmall);
-    DEBUGLOG(5, "ZSTD_writeFrameHeader : dictIDFlag : %u \n", !params.fParams.noDictIDFlag);
-    DEBUGLOG(5, "ZSTD_writeFrameHeader : dictID : %u \n", dictID);
-    DEBUGLOG(5, "ZSTD_writeFrameHeader : dictIDSizeCode : %u \n", dictIDSizeCode);
+    DEBUGLOG(5, "ZSTD_writeFrameHeader : dictIDFlag : %u ; dictID : %u ; dictIDSizeCode : %u",
+                !params.fParams.noDictIDFlag, dictID,  dictIDSizeCode);
 
     MEM_writeLE32(dst, ZSTD_MAGICNUMBER);
     op[4] = frameHeaderDecriptionByte; pos=5;
     if (!singleSegment) op[pos++] = windowLogByte;
     switch(dictIDSizeCode)
     {
-        default:   /* impossible */
+        default:  assert(0); /* impossible */
         case 0 : break;
         case 1 : op[pos] = (BYTE)(dictID); pos++; break;
         case 2 : MEM_writeLE16(op+pos, (U16)dictID); pos+=2; break;
@@ -2545,7 +2937,7 @@ static size_t ZSTD_writeFrameHeader(void* dst, size_t dstCapacity,
     }
     switch(fcsCode)
     {
-        default:   /* impossible */
+        default:  assert(0); /* impossible */
         case 0 : if (singleSegment) op[pos++] = (BYTE)(pledgedSrcSize); break;
         case 1 : MEM_writeLE16(op+pos, (U16)(pledgedSrcSize-256)); pos+=2; break;
         case 2 : MEM_writeLE32(op+pos, (U32)(pledgedSrcSize)); pos+=4; break;
@@ -2563,10 +2955,13 @@ static size_t ZSTD_compressContinue_internal (ZSTD_CCtx* cctx,
     const BYTE* const ip = (const BYTE*) src;
     size_t fhSize = 0;
 
+    DEBUGLOG(5, "ZSTD_compressContinue_internal");
+    DEBUGLOG(5, "stage: %u", cctx->stage);
     if (cctx->stage==ZSTDcs_created) return ERROR(stage_wrong);   /* missing init (ZSTD_compressBegin) */
 
     if (frame && (cctx->stage==ZSTDcs_init)) {
-        fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, cctx->frameContentSize, cctx->dictID);
+        fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->appliedParams,
+                                cctx->pledgedSrcSizePlusOne-1, cctx->dictID);
         if (ZSTD_isError(fhSize)) return fhSize;
         dstCapacity -= fhSize;
         dst = (char*)dst + fhSize;
@@ -2596,7 +2991,7 @@ static size_t ZSTD_compressContinue_internal (ZSTD_CCtx* cctx,
 
     if (srcSize) {
         size_t const cSize = frame ?
-                             ZSTD_compress_generic (cctx, dst, dstCapacity, src, srcSize, lastFrameChunk) :
+                             ZSTD_compress_frameChunk (cctx, dst, dstCapacity, src, srcSize, lastFrameChunk) :
                              ZSTD_compressBlock_internal (cctx, dst, dstCapacity, src, srcSize);
         if (ZSTD_isError(cSize)) return cSize;
         cctx->consumedSrcSize += srcSize;
@@ -2614,14 +3009,18 @@ size_t ZSTD_compressContinue (ZSTD_CCtx* cctx,
 }
 
 
-size_t ZSTD_getBlockSizeMax(ZSTD_CCtx* cctx)
+size_t ZSTD_getBlockSize(const ZSTD_CCtx* cctx)
 {
-    return MIN (ZSTD_BLOCKSIZE_ABSOLUTEMAX, 1 << cctx->params.cParams.windowLog);
+    U32 const cLevel = cctx->compressionLevel;
+    ZSTD_compressionParameters cParams = (cLevel == ZSTD_CLEVEL_CUSTOM) ?
+                                        cctx->appliedParams.cParams :
+                                        ZSTD_getCParams(cLevel, 0, 0);
+    return MIN (ZSTD_BLOCKSIZE_MAX, 1 << cParams.windowLog);
 }
 
 size_t ZSTD_compressBlock(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
 {
-    size_t const blockSizeMax = ZSTD_getBlockSizeMax(cctx);
+    size_t const blockSizeMax = ZSTD_getBlockSize(cctx);
     if (srcSize > blockSizeMax) return ERROR(srcSize_wrong);
     return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 0 /* frame mode */, 0 /* last chunk */);
 }
@@ -2645,32 +3044,32 @@ static size_t ZSTD_loadDictionaryContent(ZSTD_CCtx* zc, const void* src, size_t
     zc->nextSrc = iend;
     if (srcSize <= HASH_READ_SIZE) return 0;
 
-    switch(zc->params.cParams.strategy)
+    switch(zc->appliedParams.cParams.strategy)
     {
     case ZSTD_fast:
-        ZSTD_fillHashTable (zc, iend, zc->params.cParams.searchLength);
+        ZSTD_fillHashTable (zc, iend, zc->appliedParams.cParams.searchLength);
         break;
 
     case ZSTD_dfast:
-        ZSTD_fillDoubleHashTable (zc, iend, zc->params.cParams.searchLength);
+        ZSTD_fillDoubleHashTable (zc, iend, zc->appliedParams.cParams.searchLength);
         break;
 
     case ZSTD_greedy:
     case ZSTD_lazy:
     case ZSTD_lazy2:
         if (srcSize >= HASH_READ_SIZE)
-            ZSTD_insertAndFindFirstIndex(zc, iend-HASH_READ_SIZE, zc->params.cParams.searchLength);
+            ZSTD_insertAndFindFirstIndex(zc, iend-HASH_READ_SIZE, zc->appliedParams.cParams.searchLength);
         break;
 
     case ZSTD_btlazy2:
     case ZSTD_btopt:
-    case ZSTD_btopt2:
+    case ZSTD_btultra:
         if (srcSize >= HASH_READ_SIZE)
-            ZSTD_updateTree(zc, iend-HASH_READ_SIZE, iend, 1 << zc->params.cParams.searchLog, zc->params.cParams.searchLength);
+            ZSTD_updateTree(zc, iend-HASH_READ_SIZE, iend, 1 << zc->appliedParams.cParams.searchLog, zc->appliedParams.cParams.searchLength);
         break;
 
     default:
-        return ERROR(GENERIC);   /* strategy doesn't exist; impossible */
+        assert(0);  /* not possible : not a valid strategy id */
     }
 
     zc->nextToUpdate = (U32)(iend - zc->base);
@@ -2710,7 +3109,7 @@ static size_t ZSTD_loadZstdDictionary(ZSTD_CCtx* cctx, const void* dict, size_t
     BYTE scratchBuffer[1<<MAX(MLFSELog,LLFSELog)];
 
     dictPtr += 4;   /* skip magic number */
-    cctx->dictID = cctx->params.fParams.noDictIDFlag ? 0 :  MEM_readLE32(dictPtr);
+    cctx->dictID = cctx->appliedParams.fParams.noDictIDFlag ? 0 :  MEM_readLE32(dictPtr);
     dictPtr += 4;
 
     {   size_t const hufHeaderSize = HUF_readCTable(cctx->hufCTable, 255, dictPtr, dictEnd-dictPtr);
@@ -2781,28 +3180,56 @@ static size_t ZSTD_loadZstdDictionary(ZSTD_CCtx* cctx, const void* dict, size_t
 
 /** ZSTD_compress_insertDictionary() :
 *   @return : 0, or an error code */
-static size_t ZSTD_compress_insertDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize)
+static size_t ZSTD_compress_insertDictionary(ZSTD_CCtx* cctx,
+                                       const void* dict, size_t dictSize,
+                                             ZSTD_dictMode_e dictMode)
 {
+    DEBUGLOG(5, "ZSTD_compress_insertDictionary");
     if ((dict==NULL) || (dictSize<=8)) return 0;
 
-    /* dict as pure content */
-    if ((MEM_readLE32(dict) != ZSTD_DICT_MAGIC) || (cctx->forceRawDict))
+    /* dict restricted modes */
+    if (dictMode==ZSTD_dm_rawContent)
         return ZSTD_loadDictionaryContent(cctx, dict, dictSize);
 
-    /* dict as zstd dictionary */
+    if (MEM_readLE32(dict) != ZSTD_MAGIC_DICTIONARY) {
+        if (dictMode == ZSTD_dm_auto) {
+            DEBUGLOG(5, "raw content dictionary detected");
+            return ZSTD_loadDictionaryContent(cctx, dict, dictSize);
+        }
+        if (dictMode == ZSTD_dm_fullDict)
+            return ERROR(dictionary_wrong);
+        assert(0);   /* impossible */
+    }
+
+    /* dict as full zstd dictionary */
     return ZSTD_loadZstdDictionary(cctx, dict, dictSize);
 }
 
 /*! ZSTD_compressBegin_internal() :
-*   @return : 0, or an error code */
+ * @return : 0, or an error code */
 static size_t ZSTD_compressBegin_internal(ZSTD_CCtx* cctx,
                              const void* dict, size_t dictSize,
-                                   ZSTD_parameters params, U64 pledgedSrcSize)
+                             ZSTD_dictMode_e dictMode,
+                             const ZSTD_CDict* cdict,
+                                   ZSTD_parameters params, U64 pledgedSrcSize,
+                                   ZSTD_buffered_policy_e zbuff)
 {
-    ZSTD_compResetPolicy_e const crp = dictSize ? ZSTDcrp_fullReset : ZSTDcrp_continue;
+    DEBUGLOG(4, "ZSTD_compressBegin_internal");
+    DEBUGLOG(4, "dict ? %s", dict ? "dict" : (cdict ? "cdict" : "none"));
+    DEBUGLOG(4, "dictMode : %u", (U32)dictMode);
+    /* params are supposed to be fully validated at this point */
     assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
-    CHECK_F(ZSTD_resetCCtx_internal(cctx, params, pledgedSrcSize, crp));
-    return ZSTD_compress_insertDictionary(cctx, dict, dictSize);
+    assert(!((dict) && (cdict)));  /* either dict or cdict, not both */
+
+    if (cdict && cdict->dictContentSize>0) {
+        return ZSTD_copyCCtx_internal(cctx, cdict->refContext,
+                                      params.fParams, pledgedSrcSize,
+                                      zbuff);
+    }
+
+    CHECK_F( ZSTD_resetCCtx_internal(cctx, params, pledgedSrcSize,
+                                     ZSTDcrp_continue, zbuff) );
+    return ZSTD_compress_insertDictionary(cctx, dict, dictSize, dictMode);
 }
 
 
@@ -2814,14 +3241,16 @@ size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* cctx,
 {
     /* compression parameters verification and optimization */
     CHECK_F(ZSTD_checkCParams(params.cParams));
-    return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, pledgedSrcSize);
+    return ZSTD_compressBegin_internal(cctx, dict, dictSize, ZSTD_dm_auto, NULL,
+                                    params, pledgedSrcSize, ZSTDb_not_buffered);
 }
 
 
 size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel)
 {
     ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
-    return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, 0);
+    return ZSTD_compressBegin_internal(cctx, dict, dictSize, ZSTD_dm_auto, NULL,
+                                       params, 0, ZSTDb_not_buffered);
 }
 
 
@@ -2840,11 +3269,12 @@ static size_t ZSTD_writeEpilogue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity)
     BYTE* op = ostart;
     size_t fhSize = 0;
 
+    DEBUGLOG(5, "ZSTD_writeEpilogue");
     if (cctx->stage == ZSTDcs_created) return ERROR(stage_wrong);  /* init missing */
 
     /* special case : empty frame */
     if (cctx->stage == ZSTDcs_init) {
-        fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, 0, 0);
+        fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->appliedParams, 0, 0);
         if (ZSTD_isError(fhSize)) return fhSize;
         dstCapacity -= fhSize;
         op += fhSize;
@@ -2860,7 +3290,7 @@ static size_t ZSTD_writeEpilogue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity)
         dstCapacity -= ZSTD_blockHeaderSize;
     }
 
-    if (cctx->params.fParams.checksumFlag) {
+    if (cctx->appliedParams.fParams.checksumFlag) {
         U32 const checksum = (U32) XXH64_digest(&cctx->xxhState);
         if (dstCapacity<4) return ERROR(dstSize_tooSmall);
         MEM_writeLE32(op, checksum);
@@ -2877,13 +3307,19 @@ size_t ZSTD_compressEnd (ZSTD_CCtx* cctx,
                    const void* src, size_t srcSize)
 {
     size_t endResult;
-    size_t const cSize = ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 1 /* frame mode */, 1 /* last chunk */);
+    size_t const cSize = ZSTD_compressContinue_internal(cctx,
+                                dst, dstCapacity, src, srcSize,
+                                1 /* frame mode */, 1 /* last chunk */);
     if (ZSTD_isError(cSize)) return cSize;
     endResult = ZSTD_writeEpilogue(cctx, (char*)dst + cSize, dstCapacity-cSize);
     if (ZSTD_isError(endResult)) return endResult;
-    if (cctx->params.fParams.contentSizeFlag) {  /* control src size */
-        if (cctx->frameContentSize != cctx->consumedSrcSize) return ERROR(srcSize_wrong);
-    }
+    if (cctx->appliedParams.fParams.contentSizeFlag) {  /* control src size */
+        DEBUGLOG(5, "end of frame : controlling src size");
+        if (cctx->pledgedSrcSizePlusOne != cctx->consumedSrcSize+1) {
+            DEBUGLOG(5, "error : pledgedSrcSize = %u, while realSrcSize = %u",
+                (U32)cctx->pledgedSrcSizePlusOne-1, (U32)cctx->consumedSrcSize);
+            return ERROR(srcSize_wrong);
+    }   }
     return cSize + endResult;
 }
 
@@ -2894,7 +3330,8 @@ static size_t ZSTD_compress_internal (ZSTD_CCtx* cctx,
                          const void* dict,size_t dictSize,
                                ZSTD_parameters params)
 {
-    CHECK_F(ZSTD_compressBegin_internal(cctx, dict, dictSize, params, srcSize));
+    CHECK_F( ZSTD_compressBegin_internal(cctx, dict, dictSize, ZSTD_dm_auto, NULL,
+                                         params, srcSize, ZSTDb_not_buffered) );
     return ZSTD_compressEnd(cctx, dst,  dstCapacity, src, srcSize);
 }
 
@@ -2926,25 +3363,36 @@ size_t ZSTD_compress(void* dst, size_t dstCapacity, const void* src, size_t srcS
     size_t result;
     ZSTD_CCtx ctxBody;
     memset(&ctxBody, 0, sizeof(ctxBody));
-    memcpy(&ctxBody.customMem, &defaultCustomMem, sizeof(ZSTD_customMem));
+    ctxBody.customMem = ZSTD_defaultCMem;
     result = ZSTD_compressCCtx(&ctxBody, dst, dstCapacity, src, srcSize, compressionLevel);
-    ZSTD_free(ctxBody.workSpace, defaultCustomMem);  /* can't free ctxBody itself, as it's on stack; free only heap content */
+    ZSTD_free(ctxBody.workSpace, ZSTD_defaultCMem);  /* can't free ctxBody itself, as it's on stack; free only heap content */
     return result;
 }
 
 
 /* =====  Dictionary API  ===== */
 
-struct ZSTD_CDict_s {
-    void* dictBuffer;
-    const void* dictContent;
-    size_t dictContentSize;
-    ZSTD_CCtx* refContext;
-};  /* typedef'd tp ZSTD_CDict within "zstd.h" */
+/*! ZSTD_estimateCDictSize_advanced() :
+ *  Estimate amount of memory that will be needed to create a dictionary with following arguments */
+size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, unsigned byReference)
+{
+    DEBUGLOG(5, "sizeof(ZSTD_CDict) : %u", (U32)sizeof(ZSTD_CDict));
+    DEBUGLOG(5, "CCtx estimate : %u", (U32)ZSTD_estimateCCtxSize_advanced(cParams));
+    return sizeof(ZSTD_CDict) + ZSTD_estimateCCtxSize_advanced(cParams)
+           + (byReference ? 0 : dictSize);
+}
+
+size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel)
+{
+    ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
+    return ZSTD_estimateCDictSize_advanced(dictSize, cParams, 0);
+}
 
 size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict)
 {
     if (cdict==NULL) return 0;   /* support sizeof on NULL */
+    DEBUGLOG(5, "sizeof(*cdict) : %u", (U32)sizeof(*cdict));
+    DEBUGLOG(5, "ZSTD_sizeof_CCtx : %u", (U32)ZSTD_sizeof_CCtx(cdict->refContext));
     return ZSTD_sizeof_CCtx(cdict->refContext) + (cdict->dictBuffer ? cdict->dictContentSize : 0) + sizeof(*cdict);
 }
 
@@ -2956,13 +3404,46 @@ static ZSTD_parameters ZSTD_makeParams(ZSTD_compressionParameters cParams, ZSTD_
     return params;
 }
 
-ZSTD_CDict* ZSTD_createCDict_advanced(const void* dictBuffer, size_t dictSize, unsigned byReference,
+static size_t ZSTD_initCDict_internal(
+                    ZSTD_CDict* cdict,
+              const void* dictBuffer, size_t dictSize,
+                    unsigned byReference, ZSTD_dictMode_e dictMode,
+                    ZSTD_compressionParameters cParams)
+{
+    DEBUGLOG(5, "ZSTD_initCDict_internal, mode %u", (U32)dictMode);
+    if ((byReference) || (!dictBuffer) || (!dictSize)) {
+        cdict->dictBuffer = NULL;
+        cdict->dictContent = dictBuffer;
+    } else {
+        void* const internalBuffer = ZSTD_malloc(dictSize, cdict->refContext->customMem);
+        cdict->dictBuffer = internalBuffer;
+        cdict->dictContent = internalBuffer;
+        if (!internalBuffer) return ERROR(memory_allocation);
+        memcpy(internalBuffer, dictBuffer, dictSize);
+    }
+    cdict->dictContentSize = dictSize;
+
+    {   ZSTD_frameParameters const fParams = { 0 /* contentSizeFlag */,
+                    0 /* checksumFlag */, 0 /* noDictIDFlag */ };  /* dummy */
+        ZSTD_parameters const params = ZSTD_makeParams(cParams, fParams);
+        CHECK_F( ZSTD_compressBegin_internal(cdict->refContext,
+                                        cdict->dictContent, dictSize, dictMode,
+                                        NULL,
+                                        params, ZSTD_CONTENTSIZE_UNKNOWN,
+                                        ZSTDb_not_buffered) );
+    }
+
+    return 0;
+}
+
+ZSTD_CDict* ZSTD_createCDict_advanced(const void* dictBuffer, size_t dictSize,
+                                      unsigned byReference, ZSTD_dictMode_e dictMode,
                                       ZSTD_compressionParameters cParams, ZSTD_customMem customMem)
 {
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    DEBUGLOG(5, "ZSTD_createCDict_advanced, mode %u", (U32)dictMode);
+    if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
 
-    {   ZSTD_CDict* const cdict = (ZSTD_CDict*) ZSTD_malloc(sizeof(ZSTD_CDict), customMem);
+    {   ZSTD_CDict* const cdict = (ZSTD_CDict*)ZSTD_malloc(sizeof(ZSTD_CDict), customMem);
         ZSTD_CCtx* const cctx = ZSTD_createCCtx_advanced(customMem);
 
         if (!cdict || !cctx) {
@@ -2970,46 +3451,34 @@ ZSTD_CDict* ZSTD_createCDict_advanced(const void* dictBuffer, size_t dictSize, u
             ZSTD_freeCCtx(cctx);
             return NULL;
         }
+        cdict->refContext = cctx;
 
-        if ((byReference) || (!dictBuffer) || (!dictSize)) {
-            cdict->dictBuffer = NULL;
-            cdict->dictContent = dictBuffer;
-        } else {
-            void* const internalBuffer = ZSTD_malloc(dictSize, customMem);
-            if (!internalBuffer) { ZSTD_free(cctx, customMem); ZSTD_free(cdict, customMem); return NULL; }
-            memcpy(internalBuffer, dictBuffer, dictSize);
-            cdict->dictBuffer = internalBuffer;
-            cdict->dictContent = internalBuffer;
+        if (ZSTD_isError( ZSTD_initCDict_internal(cdict,
+                                        dictBuffer, dictSize,
+                                        byReference, dictMode,
+                                        cParams) )) {
+            ZSTD_freeCDict(cdict);
+            return NULL;
         }
 
-        {   ZSTD_frameParameters const fParams = { 0 /* contentSizeFlag */, 0 /* checksumFlag */, 0 /* noDictIDFlag */ };   /* dummy */
-            ZSTD_parameters const params = ZSTD_makeParams(cParams, fParams);
-            size_t const errorCode = ZSTD_compressBegin_advanced(cctx, cdict->dictContent, dictSize, params, 0);
-            if (ZSTD_isError(errorCode)) {
-                ZSTD_free(cdict->dictBuffer, customMem);
-                ZSTD_free(cdict, customMem);
-                ZSTD_freeCCtx(cctx);
-                return NULL;
-        }   }
-
-        cdict->refContext = cctx;
-        cdict->dictContentSize = dictSize;
         return cdict;
     }
 }
 
 ZSTD_CDict* ZSTD_createCDict(const void* dict, size_t dictSize, int compressionLevel)
 {
-    ZSTD_customMem const allocator = { NULL, NULL, NULL };
     ZSTD_compressionParameters cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
-    return ZSTD_createCDict_advanced(dict, dictSize, 0, cParams, allocator);
+    return ZSTD_createCDict_advanced(dict, dictSize,
+                                     0 /* byReference */, ZSTD_dm_auto,
+                                     cParams, ZSTD_defaultCMem);
 }
 
 ZSTD_CDict* ZSTD_createCDict_byReference(const void* dict, size_t dictSize, int compressionLevel)
 {
-    ZSTD_customMem const allocator = { NULL, NULL, NULL };
     ZSTD_compressionParameters cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
-    return ZSTD_createCDict_advanced(dict, dictSize, 1, cParams, allocator);
+    return ZSTD_createCDict_advanced(dict, dictSize,
+                                     1 /* byReference */, ZSTD_dm_auto,
+                                     cParams, ZSTD_defaultCMem);
 }
 
 size_t ZSTD_freeCDict(ZSTD_CDict* cdict)
@@ -3023,7 +3492,54 @@ size_t ZSTD_freeCDict(ZSTD_CDict* cdict)
     }
 }
 
-static ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict* cdict) {
+/*! ZSTD_initStaticCDict_advanced() :
+ *  Generate a digested dictionary in provided memory area.
+ *  workspace: The memory area to emplace the dictionary into.
+ *             Provided pointer must 8-bytes aligned.
+ *             It must outlive dictionary usage.
+ *  workspaceSize: Use ZSTD_estimateCDictSize()
+ *                 to determine how large workspace must be.
+ *  cParams : use ZSTD_getCParams() to transform a compression level
+ *            into its relevants cParams.
+ * @return : pointer to ZSTD_CDict*, or NULL if error (size too small)
+ *  Note : there is no corresponding "free" function.
+ *         Since workspace was allocated externally, it must be freed externally.
+ */
+ZSTD_CDict* ZSTD_initStaticCDict(void* workspace, size_t workspaceSize,
+                           const void* dict, size_t dictSize,
+                                 unsigned byReference, ZSTD_dictMode_e dictMode,
+                                 ZSTD_compressionParameters cParams)
+{
+    size_t const cctxSize = ZSTD_estimateCCtxSize_advanced(cParams);
+    size_t const neededSize = sizeof(ZSTD_CDict) + (byReference ? 0 : dictSize)
+                            + cctxSize;
+    ZSTD_CDict* const cdict = (ZSTD_CDict*) workspace;
+    void* ptr;
+    DEBUGLOG(5, "(size_t)workspace & 7 : %u", (U32)(size_t)workspace & 7);
+    if ((size_t)workspace & 7) return NULL;  /* 8-aligned */
+    DEBUGLOG(5, "(workspaceSize < neededSize) : (%u < %u) => %u",
+        (U32)workspaceSize, (U32)neededSize, (U32)(workspaceSize < neededSize));
+    if (workspaceSize < neededSize) return NULL;
+
+    if (!byReference) {
+        memcpy(cdict+1, dict, dictSize);
+        dict = cdict+1;
+        ptr = (char*)workspace + sizeof(ZSTD_CDict) + dictSize;
+    } else {
+        ptr = cdict+1;
+    }
+    cdict->refContext = ZSTD_initStaticCCtx(ptr, cctxSize);
+
+    if (ZSTD_isError( ZSTD_initCDict_internal(cdict,
+                                              dict, dictSize,
+                                              1 /* byReference */, dictMode,
+                                              cParams) ))
+        return NULL;
+
+    return cdict;
+}
+
+ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict* cdict) {
     return ZSTD_getParamsFromCCtx(cdict->refContext);
 }
 
@@ -3033,16 +3549,16 @@ size_t ZSTD_compressBegin_usingCDict_advanced(
     ZSTD_CCtx* const cctx, const ZSTD_CDict* const cdict,
     ZSTD_frameParameters const fParams, unsigned long long const pledgedSrcSize)
 {
-    if (cdict==NULL) return ERROR(GENERIC);  /* does not support NULL cdict */
-    DEBUGLOG(5, "ZSTD_compressBegin_usingCDict_advanced : dictIDFlag == %u \n", !fParams.noDictIDFlag);
-    if (cdict->dictContentSize)
-        CHECK_F( ZSTD_copyCCtx_internal(cctx, cdict->refContext, fParams, pledgedSrcSize) )
-    else {
-        ZSTD_parameters params = cdict->refContext->params;
+    if (cdict==NULL) return ERROR(dictionary_wrong);
+    {   ZSTD_parameters params = cdict->refContext->appliedParams;
         params.fParams = fParams;
-        CHECK_F(ZSTD_compressBegin_internal(cctx, NULL, 0, params, pledgedSrcSize));
+        DEBUGLOG(5, "ZSTD_compressBegin_usingCDict_advanced");
+        return ZSTD_compressBegin_internal(cctx,
+                                           NULL, 0, ZSTD_dm_auto,
+                                           cdict,
+                                           params, pledgedSrcSize,
+                                           ZSTDb_not_buffered);
     }
-    return 0;
 }
 
 /* ZSTD_compressBegin_usingCDict() :
@@ -3051,7 +3567,7 @@ size_t ZSTD_compressBegin_usingCDict_advanced(
 size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict)
 {
     ZSTD_frameParameters const fParams = { 0 /*content*/, 0 /*checksum*/, 0 /*noDictID*/ };
-    DEBUGLOG(5, "ZSTD_compressBegin_usingCDict : dictIDFlag == %u \n", !fParams.noDictIDFlag);
+    DEBUGLOG(5, "ZSTD_compressBegin_usingCDict : dictIDFlag == %u", !fParams.noDictIDFlag);
     return ZSTD_compressBegin_usingCDict_advanced(cctx, cdict, fParams, 0);
 }
 
@@ -3084,176 +3600,133 @@ size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
 *  Streaming
 ********************************************************************/
 
-typedef enum { zcss_init, zcss_load, zcss_flush, zcss_final } ZSTD_cStreamStage;
-
-struct ZSTD_CStream_s {
-    ZSTD_CCtx* cctx;
-    ZSTD_CDict* cdictLocal;
-    const ZSTD_CDict* cdict;
-    char*  inBuff;
-    size_t inBuffSize;
-    size_t inToCompress;
-    size_t inBuffPos;
-    size_t inBuffTarget;
-    size_t blockSize;
-    char*  outBuff;
-    size_t outBuffSize;
-    size_t outBuffContentSize;
-    size_t outBuffFlushedSize;
-    ZSTD_cStreamStage stage;
-    U32    checksum;
-    U32    frameEnded;
-    U64    pledgedSrcSize;
-    ZSTD_parameters params;
-    ZSTD_customMem customMem;
-};   /* typedef'd to ZSTD_CStream within "zstd.h" */
-
 ZSTD_CStream* ZSTD_createCStream(void)
 {
-    return ZSTD_createCStream_advanced(defaultCustomMem);
+    return ZSTD_createCStream_advanced(ZSTD_defaultCMem);
 }
 
-ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem)
+ZSTD_CStream* ZSTD_initStaticCStream(void *workspace, size_t workspaceSize)
 {
-    ZSTD_CStream* zcs;
-
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    return ZSTD_initStaticCCtx(workspace, workspaceSize);
+}
 
-    zcs = (ZSTD_CStream*)ZSTD_malloc(sizeof(ZSTD_CStream), customMem);
-    if (zcs==NULL) return NULL;
-    memset(zcs, 0, sizeof(ZSTD_CStream));
-    memcpy(&zcs->customMem, &customMem, sizeof(ZSTD_customMem));
-    zcs->cctx = ZSTD_createCCtx_advanced(customMem);
-    if (zcs->cctx == NULL) { ZSTD_freeCStream(zcs); return NULL; }
-    return zcs;
+ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem)
+{   /* CStream and CCtx are now same object */
+    return ZSTD_createCCtx_advanced(customMem);
 }
 
 size_t ZSTD_freeCStream(ZSTD_CStream* zcs)
 {
-    if (zcs==NULL) return 0;   /* support free on NULL */
-    {   ZSTD_customMem const cMem = zcs->customMem;
-        ZSTD_freeCCtx(zcs->cctx);
-        zcs->cctx = NULL;
-        ZSTD_freeCDict(zcs->cdictLocal);
-        zcs->cdictLocal = NULL;
-        ZSTD_free(zcs->inBuff, cMem);
-        zcs->inBuff = NULL;
-        ZSTD_free(zcs->outBuff, cMem);
-        zcs->outBuff = NULL;
-        ZSTD_free(zcs, cMem);
-        return 0;
-    }
+    return ZSTD_freeCCtx(zcs);   /* same object */
 }
 
 
+
 /*======   Initialization   ======*/
 
-size_t ZSTD_CStreamInSize(void)  { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
+size_t ZSTD_CStreamInSize(void)  { return ZSTD_BLOCKSIZE_MAX; }
 
 size_t ZSTD_CStreamOutSize(void)
 {
-    return ZSTD_compressBound(ZSTD_BLOCKSIZE_ABSOLUTEMAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */ ;
+    return ZSTD_compressBound(ZSTD_BLOCKSIZE_MAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */ ;
 }
 
-static size_t ZSTD_resetCStream_internal(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
+static size_t ZSTD_resetCStream_internal(ZSTD_CStream* zcs,
+                    const void* dict, size_t dictSize, ZSTD_dictMode_e dictMode,
+                    const ZSTD_CDict* cdict,
+                    ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
-    if (zcs->inBuffSize==0) return ERROR(stage_wrong);   /* zcs has not been init at least once => can't reset */
-
-    DEBUGLOG(5, "ZSTD_resetCStream_internal : dictIDFlag == %u \n", !zcs->params.fParams.noDictIDFlag);
+    DEBUGLOG(4, "ZSTD_resetCStream_internal");
+    /* params are supposed to be fully validated at this point */
+    assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
+    assert(!((dict) && (cdict)));  /* either dict or cdict, not both */
 
-    if (zcs->cdict) CHECK_F(ZSTD_compressBegin_usingCDict_advanced(zcs->cctx, zcs->cdict, zcs->params.fParams, pledgedSrcSize))
-    else CHECK_F(ZSTD_compressBegin_internal(zcs->cctx, NULL, 0, zcs->params, pledgedSrcSize));
+    CHECK_F( ZSTD_compressBegin_internal(zcs,
+                                        dict, dictSize, dictMode,
+                                        cdict,
+                                        params, pledgedSrcSize,
+                                        ZSTDb_buffered) );
 
     zcs->inToCompress = 0;
     zcs->inBuffPos = 0;
     zcs->inBuffTarget = zcs->blockSize;
     zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0;
-    zcs->stage = zcss_load;
+    zcs->streamStage = zcss_load;
     zcs->frameEnded = 0;
-    zcs->pledgedSrcSize = pledgedSrcSize;
     return 0;   /* ready to go */
 }
 
 size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
 {
-
-    zcs->params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
-    DEBUGLOG(5, "ZSTD_resetCStream : dictIDFlag == %u \n", !zcs->params.fParams.noDictIDFlag);
-    return ZSTD_resetCStream_internal(zcs, pledgedSrcSize);
+    ZSTD_parameters params = zcs->requestedParams;
+    params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
+    DEBUGLOG(5, "ZSTD_resetCStream");
+    if (zcs->compressionLevel != ZSTD_CLEVEL_CUSTOM) {
+        params.cParams = ZSTD_getCParams(zcs->compressionLevel, pledgedSrcSize, 0 /* dictSize */);
+    }
+    return ZSTD_resetCStream_internal(zcs, NULL, 0, zcs->dictMode, zcs->cdict, params, pledgedSrcSize);
 }
 
-/* ZSTD_initCStream_internal() :
- * params are supposed validated at this stage
- * and zcs->cdict is supposed to be correct */
-static size_t ZSTD_initCStream_stage2(ZSTD_CStream* zcs,
-                                const ZSTD_parameters params,
-                                unsigned long long pledgedSrcSize)
+/*! ZSTD_initCStream_internal() :
+ *  Note : not static, but hidden (not exposed). Used by zstdmt_compress.c
+ *  Assumption 1 : params are valid
+ *  Assumption 2 : either dict, or cdict, is defined, not both */
+size_t ZSTD_initCStream_internal(ZSTD_CStream* zcs,
+                    const void* dict, size_t dictSize, const ZSTD_CDict* cdict,
+                    ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
+    DEBUGLOG(5, "ZSTD_initCStream_internal");
     assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
+    assert(!((dict) && (cdict)));  /* either dict or cdict, not both */
 
-    /* allocate buffers */
-    {   size_t const neededInBuffSize = (size_t)1 << params.cParams.windowLog;
-        if (zcs->inBuffSize < neededInBuffSize) {
-            zcs->inBuffSize = 0;
-            ZSTD_free(zcs->inBuff, zcs->customMem);
-            zcs->inBuff = (char*) ZSTD_malloc(neededInBuffSize, zcs->customMem);
-            if (zcs->inBuff == NULL) return ERROR(memory_allocation);
-            zcs->inBuffSize = neededInBuffSize;
+    if (dict && dictSize >= 8) {
+        DEBUGLOG(5, "loading dictionary of size %u", (U32)dictSize);
+        if (zcs->staticSize) {   /* static CCtx : never uses malloc */
+            /* incompatible with internal cdict creation */
+            return ERROR(memory_allocation);
         }
-        zcs->blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, neededInBuffSize);
-    }
-    if (zcs->outBuffSize < ZSTD_compressBound(zcs->blockSize)+1) {
-        size_t const outBuffSize = ZSTD_compressBound(zcs->blockSize)+1;
-        zcs->outBuffSize = 0;
-        ZSTD_free(zcs->outBuff, zcs->customMem);
-        zcs->outBuff = (char*) ZSTD_malloc(outBuffSize, zcs->customMem);
-        if (zcs->outBuff == NULL) return ERROR(memory_allocation);
-        zcs->outBuffSize = outBuffSize;
+        ZSTD_freeCDict(zcs->cdictLocal);
+        zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize,
+                                            zcs->dictContentByRef, zcs->dictMode,
+                                            params.cParams, zcs->customMem);
+        zcs->cdict = zcs->cdictLocal;
+        if (zcs->cdictLocal == NULL) return ERROR(memory_allocation);
+    } else {
+        if (cdict) {
+            ZSTD_parameters const cdictParams = ZSTD_getParamsFromCDict(cdict);
+            params.cParams = cdictParams.cParams;  /* cParams are enforced from cdict */
+        }
+        ZSTD_freeCDict(zcs->cdictLocal);
+        zcs->cdictLocal = NULL;
+        zcs->cdict = cdict;
     }
 
-    zcs->checksum = params.fParams.checksumFlag > 0;
-    zcs->params = params;
-
-    DEBUGLOG(5, "ZSTD_initCStream_stage2 : dictIDFlag == %u \n", !params.fParams.noDictIDFlag);
-    return ZSTD_resetCStream_internal(zcs, pledgedSrcSize);
+    zcs->requestedParams = params;
+    zcs->compressionLevel = ZSTD_CLEVEL_CUSTOM;
+    return ZSTD_resetCStream_internal(zcs, NULL, 0, zcs->dictMode, zcs->cdict, params, pledgedSrcSize);
 }
 
 /* ZSTD_initCStream_usingCDict_advanced() :
  * same as ZSTD_initCStream_usingCDict(), with control over frame parameters */
-size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize, ZSTD_frameParameters fParams)
-{
-    if (!cdict) return ERROR(GENERIC);   /* cannot handle NULL cdict (does not know what to do) */
+size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs,
+                                            const ZSTD_CDict* cdict,
+                                            ZSTD_frameParameters fParams,
+                                            unsigned long long pledgedSrcSize)
+{   /* cannot handle NULL cdict (does not know what to do) */
+    if (!cdict) return ERROR(dictionary_wrong);
     {   ZSTD_parameters params = ZSTD_getParamsFromCDict(cdict);
         params.fParams = fParams;
-        zcs->cdict = cdict;
-        return ZSTD_initCStream_stage2(zcs, params, pledgedSrcSize);
+        return ZSTD_initCStream_internal(zcs,
+                                NULL, 0, cdict,
+                                params, pledgedSrcSize);
     }
 }
 
 /* note : cdict must outlive compression session */
 size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict)
 {
-    ZSTD_frameParameters const fParams = { 0 /* content */, 0 /* checksum */, 0 /* noDictID */ };
-    return ZSTD_initCStream_usingCDict_advanced(zcs, cdict, 0, fParams);
-}
-
-static size_t ZSTD_initCStream_internal(ZSTD_CStream* zcs,
-                                const void* dict, size_t dictSize,
-                                ZSTD_parameters params, unsigned long long pledgedSrcSize)
-{
-    assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
-    zcs->cdict = NULL;
-
-    if (dict && dictSize >= 8) {
-        ZSTD_freeCDict(zcs->cdictLocal);
-        zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize, 0 /* copy */, params.cParams, zcs->customMem);
-        if (zcs->cdictLocal == NULL) return ERROR(memory_allocation);
-        zcs->cdict = zcs->cdictLocal;
-    }
-
-    DEBUGLOG(5, "ZSTD_initCStream_internal : dictIDFlag == %u \n", !params.fParams.noDictIDFlag);
-    return ZSTD_initCStream_stage2(zcs, params, pledgedSrcSize);
+    ZSTD_frameParameters const fParams = { 0 /* contentSize */, 0 /* checksum */, 0 /* hideDictID */ };
+    return ZSTD_initCStream_usingCDict_advanced(zcs, cdict, fParams, 0);  /* note : will check that cdict != NULL */
 }
 
 size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs,
@@ -3261,120 +3734,180 @@ size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs,
                                  ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
     CHECK_F( ZSTD_checkCParams(params.cParams) );
-    DEBUGLOG(5, "ZSTD_initCStream_advanced : dictIDFlag == %u \n", !params.fParams.noDictIDFlag);
-    return ZSTD_initCStream_internal(zcs, dict, dictSize, params, pledgedSrcSize);
+    zcs->requestedParams = params;
+    zcs->compressionLevel = ZSTD_CLEVEL_CUSTOM;
+    return ZSTD_initCStream_internal(zcs, dict, dictSize, NULL, params, pledgedSrcSize);
 }
 
 size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel)
 {
     ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
-    return ZSTD_initCStream_internal(zcs, dict, dictSize, params, 0);
+    zcs->compressionLevel = compressionLevel;
+    return ZSTD_initCStream_internal(zcs, dict, dictSize, NULL, params, 0);
 }
 
 size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize)
 {
     ZSTD_parameters params = ZSTD_getParams(compressionLevel, pledgedSrcSize, 0);
     params.fParams.contentSizeFlag = (pledgedSrcSize>0);
-    return ZSTD_initCStream_internal(zcs, NULL, 0, params, pledgedSrcSize);
+    return ZSTD_initCStream_internal(zcs, NULL, 0, NULL, params, pledgedSrcSize);
 }
 
 size_t ZSTD_initCStream(ZSTD_CStream* zcs, int compressionLevel)
 {
     ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, 0);
-    return ZSTD_initCStream_internal(zcs, NULL, 0, params, 0);
-}
-
-size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs)
-{
-    if (zcs==NULL) return 0;   /* support sizeof on NULL */
-    return sizeof(*zcs) + ZSTD_sizeof_CCtx(zcs->cctx) + ZSTD_sizeof_CDict(zcs->cdictLocal) + zcs->outBuffSize + zcs->inBuffSize;
+    return ZSTD_initCStream_internal(zcs, NULL, 0, NULL, params, 0);
 }
 
 /*======   Compression   ======*/
 
-typedef enum { zsf_gather, zsf_flush, zsf_end } ZSTD_flush_e;
-
-MEM_STATIC size_t ZSTD_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
+MEM_STATIC size_t ZSTD_limitCopy(void* dst, size_t dstCapacity,
+                           const void* src, size_t srcSize)
 {
     size_t const length = MIN(dstCapacity, srcSize);
-    memcpy(dst, src, length);
+    if (length) memcpy(dst, src, length);
     return length;
 }
 
-static size_t ZSTD_compressStream_generic(ZSTD_CStream* zcs,
-                              void* dst, size_t* dstCapacityPtr,
-                        const void* src, size_t* srcSizePtr,
-                              ZSTD_flush_e const flush)
+/** ZSTD_compressStream_generic():
+ *  internal function for all *compressStream*() variants and *compress_generic()
+ * @return : hint size for next input */
+size_t ZSTD_compressStream_generic(ZSTD_CStream* zcs,
+                                   ZSTD_outBuffer* output,
+                                   ZSTD_inBuffer* input,
+                                   ZSTD_EndDirective const flushMode)
 {
+    const char* const istart = (const char*)input->src;
+    const char* const iend = istart + input->size;
+    const char* ip = istart + input->pos;
+    char* const ostart = (char*)output->dst;
+    char* const oend = ostart + output->size;
+    char* op = ostart + output->pos;
     U32 someMoreWork = 1;
-    const char* const istart = (const char*)src;
-    const char* const iend = istart + *srcSizePtr;
-    const char* ip = istart;
-    char* const ostart = (char*)dst;
-    char* const oend = ostart + *dstCapacityPtr;
-    char* op = ostart;
+
+    /* check expectations */
+    DEBUGLOG(5, "ZSTD_compressStream_generic, flush=%u", (U32)flushMode);
+    assert(zcs->inBuff != NULL);
+    assert(zcs->inBuffSize>0);
+    assert(zcs->outBuff!= NULL);
+    assert(zcs->outBuffSize>0);
+    assert(output->pos <= output->size);
+    assert(input->pos <= input->size);
 
     while (someMoreWork) {
-        switch(zcs->stage)
+        switch(zcs->streamStage)
         {
-        case zcss_init: return ERROR(init_missing);   /* call ZBUFF_compressInit() first ! */
+        case zcss_init:
+            /* call ZSTD_initCStream() first ! */
+            return ERROR(init_missing);
 
         case zcss_load:
-            /* complete inBuffer */
+            if ( (flushMode == ZSTD_e_end)
+              && ((size_t)(oend-op) >= ZSTD_compressBound(iend-ip))  /* enough dstCapacity */
+              && (zcs->inBuffPos == 0) ) {
+                /* shortcut to compression pass directly into output buffer */
+                size_t const cSize = ZSTD_compressEnd(zcs,
+                                                op, oend-op, ip, iend-ip);
+                DEBUGLOG(4, "ZSTD_compressEnd : %u", (U32)cSize);
+                if (ZSTD_isError(cSize)) return cSize;
+                ip = iend;
+                op += cSize;
+                zcs->frameEnded = 1;
+                ZSTD_startNewCompression(zcs);
+                someMoreWork = 0; break;
+            }
+            /* complete loading into inBuffer */
             {   size_t const toLoad = zcs->inBuffTarget - zcs->inBuffPos;
-                size_t const loaded = ZSTD_limitCopy(zcs->inBuff + zcs->inBuffPos, toLoad, ip, iend-ip);
+                size_t const loaded = ZSTD_limitCopy(
+                                        zcs->inBuff + zcs->inBuffPos, toLoad,
+                                        ip, iend-ip);
                 zcs->inBuffPos += loaded;
                 ip += loaded;
-                if ( (zcs->inBuffPos==zcs->inToCompress) || (!flush && (toLoad != loaded)) ) {
-                    someMoreWork = 0; break;  /* not enough input to get a full block : stop there, wait for more */
-            }   }
+                if ( (flushMode == ZSTD_e_continue)
+                  && (zcs->inBuffPos < zcs->inBuffTarget) ) {
+                    /* not enough input to fill full block : stop here */
+                    someMoreWork = 0; break;
+                }
+                if ( (flushMode == ZSTD_e_flush)
+                  && (zcs->inBuffPos == zcs->inToCompress) ) {
+                    /* empty */
+                    someMoreWork = 0; break;
+                }
+            }
             /* compress current block (note : this stage cannot be stopped in the middle) */
+            DEBUGLOG(5, "stream compression stage (flushMode==%u)", flushMode);
             {   void* cDst;
                 size_t cSize;
                 size_t const iSize = zcs->inBuffPos - zcs->inToCompress;
                 size_t oSize = oend-op;
+                unsigned const lastBlock = (flushMode == ZSTD_e_end) && (ip==iend);
                 if (oSize >= ZSTD_compressBound(iSize))
-                    cDst = op;   /* compress directly into output buffer (avoid flush stage) */
+                    cDst = op;   /* compress into output buffer, to skip flush stage */
                 else
                     cDst = zcs->outBuff, oSize = zcs->outBuffSize;
-                cSize = (flush == zsf_end) ?
-                        ZSTD_compressEnd(zcs->cctx, cDst, oSize, zcs->inBuff + zcs->inToCompress, iSize) :
-                        ZSTD_compressContinue(zcs->cctx, cDst, oSize, zcs->inBuff + zcs->inToCompress, iSize);
+                cSize = lastBlock ?
+                        ZSTD_compressEnd(zcs, cDst, oSize,
+                                    zcs->inBuff + zcs->inToCompress, iSize) :
+                        ZSTD_compressContinue(zcs, cDst, oSize,
+                                    zcs->inBuff + zcs->inToCompress, iSize);
                 if (ZSTD_isError(cSize)) return cSize;
-                if (flush == zsf_end) zcs->frameEnded = 1;
+                zcs->frameEnded = lastBlock;
                 /* prepare next block */
                 zcs->inBuffTarget = zcs->inBuffPos + zcs->blockSize;
                 if (zcs->inBuffTarget > zcs->inBuffSize)
-                    zcs->inBuffPos = 0, zcs->inBuffTarget = zcs->blockSize;   /* note : inBuffSize >= blockSize */
+                    zcs->inBuffPos = 0, zcs->inBuffTarget = zcs->blockSize;
+                DEBUGLOG(5, "inBuffTarget:%u / inBuffSize:%u",
+                         (U32)zcs->inBuffTarget, (U32)zcs->inBuffSize);
+                if (!lastBlock)
+                    assert(zcs->inBuffTarget <= zcs->inBuffSize);
                 zcs->inToCompress = zcs->inBuffPos;
-                if (cDst == op) { op += cSize; break; }   /* no need to flush */
+                if (cDst == op) {  /* no need to flush */
+                    op += cSize;
+                    if (zcs->frameEnded) {
+                        DEBUGLOG(5, "Frame completed directly in outBuffer");
+                        someMoreWork = 0;
+                        ZSTD_startNewCompression(zcs);
+                    }
+                    break;
+                }
                 zcs->outBuffContentSize = cSize;
                 zcs->outBuffFlushedSize = 0;
-                zcs->stage = zcss_flush;   /* pass-through to flush stage */
+                zcs->streamStage = zcss_flush; /* pass-through to flush stage */
             }
-
+	    /* fall-through */
         case zcss_flush:
+            DEBUGLOG(5, "flush stage");
             {   size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
-                size_t const flushed = ZSTD_limitCopy(op, oend-op, zcs->outBuff + zcs->outBuffFlushedSize, toFlush);
+                size_t const flushed = ZSTD_limitCopy(op, oend-op,
+                            zcs->outBuff + zcs->outBuffFlushedSize, toFlush);
+                DEBUGLOG(5, "toFlush: %u into %u ==> flushed: %u",
+                            (U32)toFlush, (U32)(oend-op), (U32)flushed);
                 op += flushed;
                 zcs->outBuffFlushedSize += flushed;
-                if (toFlush!=flushed) { someMoreWork = 0; break; }  /* dst too small to store flushed data : stop there */
+                if (toFlush!=flushed) {
+                    /* flush not fully completed, presumably because dst is too small */
+                    assert(op==oend);
+                    someMoreWork = 0;
+                    break;
+                }
                 zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0;
-                zcs->stage = zcss_load;
+                if (zcs->frameEnded) {
+                    DEBUGLOG(5, "Frame completed on flush");
+                    someMoreWork = 0;
+                    ZSTD_startNewCompression(zcs);
+                    break;
+                }
+                zcs->streamStage = zcss_load;
                 break;
             }
 
-        case zcss_final:
-            someMoreWork = 0;   /* do nothing */
-            break;
-
-        default:
-            return ERROR(GENERIC);   /* impossible */
+        default: /* impossible */
+            assert(0);
         }
     }
 
-    *srcSizePtr = ip - istart;
-    *dstCapacityPtr = op - ostart;
+    input->pos = ip - istart;
+    output->pos = op - ostart;
     if (zcs->frameEnded) return 0;
     {   size_t hintInSize = zcs->inBuffTarget - zcs->inBuffPos;
         if (hintInSize==0) hintInSize = zcs->blockSize;
@@ -3384,14 +3917,86 @@ static size_t ZSTD_compressStream_generic(ZSTD_CStream* zcs,
 
 size_t ZSTD_compressStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input)
 {
-    size_t sizeRead = input->size - input->pos;
-    size_t sizeWritten = output->size - output->pos;
-    size_t const result = ZSTD_compressStream_generic(zcs,
-                                                      (char*)(output->dst) + output->pos, &sizeWritten,
-                                                      (const char*)(input->src) + input->pos, &sizeRead, zsf_gather);
-    input->pos += sizeRead;
-    output->pos += sizeWritten;
-    return result;
+    /* check conditions */
+    if (output->pos > output->size) return ERROR(GENERIC);
+    if (input->pos  > input->size)  return ERROR(GENERIC);
+
+    return ZSTD_compressStream_generic(zcs, output, input, ZSTD_e_continue);
+}
+
+/*! ZSTDMT_initCStream_internal() :
+ *  Private use only. Init streaming operation.
+ *  expects params to be valid.
+ *  must receive dict, or cdict, or none, but not both.
+ *  @return : 0, or an error code */
+size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
+                    const void* dict, size_t dictSize, const ZSTD_CDict* cdict,
+                    ZSTD_parameters params, unsigned long long pledgedSrcSize);
+
+
+size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
+                              ZSTD_outBuffer* output,
+                              ZSTD_inBuffer* input,
+                              ZSTD_EndDirective endOp)
+{
+    /* check conditions */
+    if (output->pos > output->size) return ERROR(GENERIC);
+    if (input->pos  > input->size)  return ERROR(GENERIC);
+    assert(cctx!=NULL);
+
+    /* transparent initialization stage */
+    if (cctx->streamStage == zcss_init) {
+        const void* const prefix = cctx->prefix;
+        size_t const prefixSize = cctx->prefixSize;
+        ZSTD_parameters params = cctx->requestedParams;
+        if (cctx->compressionLevel != ZSTD_CLEVEL_CUSTOM)
+            params.cParams = ZSTD_getCParams(cctx->compressionLevel,
+                                cctx->pledgedSrcSizePlusOne-1, 0 /*dictSize*/);
+        cctx->prefix = NULL; cctx->prefixSize = 0;   /* single usage */
+        assert(prefix==NULL || cctx->cdict==NULL);   /* only one can be set */
+
+#ifdef ZSTD_MULTITHREAD
+        if (cctx->nbThreads > 1) {
+            DEBUGLOG(4, "call ZSTDMT_initCStream_internal as nbThreads=%u", cctx->nbThreads);
+            CHECK_F( ZSTDMT_initCStream_internal(cctx->mtctx, prefix, prefixSize, cctx->cdict, params, cctx->pledgedSrcSizePlusOne-1) );
+            cctx->streamStage = zcss_load;
+        } else
+#endif
+        {
+            CHECK_F( ZSTD_resetCStream_internal(cctx, prefix, prefixSize, cctx->dictMode, cctx->cdict, params, cctx->pledgedSrcSizePlusOne-1) );
+    }   }
+
+    /* compression stage */
+#ifdef ZSTD_MULTITHREAD
+    if (cctx->nbThreads > 1) {
+        size_t const flushMin = ZSTDMT_compressStream_generic(cctx->mtctx, output, input, endOp);
+        DEBUGLOG(5, "ZSTDMT_compressStream_generic : %u", (U32)flushMin);
+        if ( ZSTD_isError(flushMin)
+          || (endOp == ZSTD_e_end && flushMin == 0) ) { /* compression completed */
+            ZSTD_startNewCompression(cctx);
+        }
+        return flushMin;
+    }
+#endif
+
+    CHECK_F( ZSTD_compressStream_generic(cctx, output, input, endOp) );
+    DEBUGLOG(5, "completed ZSTD_compress_generic");
+    return cctx->outBuffContentSize - cctx->outBuffFlushedSize; /* remaining to flush */
+}
+
+size_t ZSTD_compress_generic_simpleArgs (
+                            ZSTD_CCtx* cctx,
+                            void* dst, size_t dstCapacity, size_t* dstPos,
+                      const void* src, size_t srcSize, size_t* srcPos,
+                            ZSTD_EndDirective endOp)
+{
+    ZSTD_outBuffer output = { dst, dstCapacity, *dstPos };
+    ZSTD_inBuffer  input  = { src, srcSize, *srcPos };
+    /* ZSTD_compress_generic() will check validity of dstPos and srcPos */
+    size_t const cErr = ZSTD_compress_generic(cctx, &output, &input, endOp);
+    *dstPos = output.pos;
+    *srcPos = input.pos;
+    return cErr;
 }
 
 
@@ -3401,89 +4006,59 @@ size_t ZSTD_compressStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output, ZSTD_inBuf
 *   @return : amount of data remaining to flush */
 size_t ZSTD_flushStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output)
 {
-    size_t srcSize = 0;
-    size_t sizeWritten = output->size - output->pos;
-    size_t const result = ZSTD_compressStream_generic(zcs,
-                                                     (char*)(output->dst) + output->pos, &sizeWritten,
-                                                     &srcSize, &srcSize, /* use a valid src address instead of NULL */
-                                                      zsf_flush);
-    output->pos += sizeWritten;
-    if (ZSTD_isError(result)) return result;
-    return zcs->outBuffContentSize - zcs->outBuffFlushedSize;   /* remaining to flush */
+    ZSTD_inBuffer input = { NULL, 0, 0 };
+    if (output->pos > output->size) return ERROR(GENERIC);
+    CHECK_F( ZSTD_compressStream_generic(zcs, output, &input, ZSTD_e_flush) );
+    return zcs->outBuffContentSize - zcs->outBuffFlushedSize;  /* remaining to flush */
 }
 
 
 size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output)
 {
-    BYTE* const ostart = (BYTE*)(output->dst) + output->pos;
-    BYTE* const oend = (BYTE*)(output->dst) + output->size;
-    BYTE* op = ostart;
-
-    if (zcs->stage != zcss_final) {
-        /* flush whatever remains */
-        size_t srcSize = 0;
-        size_t sizeWritten = output->size - output->pos;
-        size_t const notEnded = ZSTD_compressStream_generic(zcs, ostart, &sizeWritten,
-                                     &srcSize /* use a valid src address instead of NULL */, &srcSize, zsf_end);
-        size_t const remainingToFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
-        op += sizeWritten;
-        if (remainingToFlush) {
-            output->pos += sizeWritten;
-            return remainingToFlush + ZSTD_BLOCKHEADERSIZE /* final empty block */ + (zcs->checksum * 4);
-        }
-        /* create epilogue */
-        zcs->stage = zcss_final;
-        zcs->outBuffContentSize = !notEnded ? 0 :
-            /* write epilogue, including final empty block, into outBuff */
-            ZSTD_compressEnd(zcs->cctx, zcs->outBuff, zcs->outBuffSize, NULL, 0);
-        if (ZSTD_isError(zcs->outBuffContentSize)) return zcs->outBuffContentSize;
-    }
-
-    /* flush epilogue */
-    {   size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
-        size_t const flushed = ZSTD_limitCopy(op, oend-op, zcs->outBuff + zcs->outBuffFlushedSize, toFlush);
-        op += flushed;
-        zcs->outBuffFlushedSize += flushed;
-        output->pos += op-ostart;
-        if (toFlush==flushed) zcs->stage = zcss_init;  /* end reached */
-        return toFlush - flushed;
+    ZSTD_inBuffer input = { NULL, 0, 0 };
+    if (output->pos > output->size) return ERROR(GENERIC);
+    CHECK_F( ZSTD_compressStream_generic(zcs, output, &input, ZSTD_e_end) );
+    {   size_t const lastBlockSize = zcs->frameEnded ? 0 : ZSTD_BLOCKHEADERSIZE;
+        size_t const checksumSize = zcs->frameEnded ? 0 : zcs->appliedParams.fParams.checksumFlag * 4;
+        size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize + lastBlockSize + checksumSize;
+        DEBUGLOG(5, "ZSTD_endStream : remaining to flush : %u",
+                (unsigned)toFlush);
+        return toFlush;
     }
 }
 
 
-
 /*-=====  Pre-defined compression levels  =====-*/
 
-#define ZSTD_DEFAULT_CLEVEL 1
 #define ZSTD_MAX_CLEVEL     22
 int ZSTD_maxCLevel(void) { return ZSTD_MAX_CLEVEL; }
 
 static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEVEL+1] = {
-{   /* "default" */
+{   /* "default" - guarantees a monotonically increasing memory budget */
     /* W,  C,  H,  S,  L, TL, strat */
     { 18, 12, 12,  1,  7, 16, ZSTD_fast    },  /* level  0 - never used */
     { 19, 13, 14,  1,  7, 16, ZSTD_fast    },  /* level  1 */
     { 19, 15, 16,  1,  6, 16, ZSTD_fast    },  /* level  2 */
-    { 20, 16, 17,  1,  5, 16, ZSTD_dfast   },  /* level  3.*/
-    { 20, 18, 18,  1,  5, 16, ZSTD_dfast   },  /* level  4.*/
-    { 20, 15, 18,  3,  5, 16, ZSTD_greedy  },  /* level  5 */
-    { 21, 16, 19,  2,  5, 16, ZSTD_lazy    },  /* level  6 */
-    { 21, 17, 20,  3,  5, 16, ZSTD_lazy    },  /* level  7 */
+    { 20, 16, 17,  1,  5, 16, ZSTD_dfast   },  /* level  3 */
+    { 20, 17, 18,  1,  5, 16, ZSTD_dfast   },  /* level  4 */
+    { 20, 17, 18,  2,  5, 16, ZSTD_greedy  },  /* level  5 */
+    { 21, 17, 19,  2,  5, 16, ZSTD_lazy    },  /* level  6 */
+    { 21, 18, 19,  3,  5, 16, ZSTD_lazy    },  /* level  7 */
     { 21, 18, 20,  3,  5, 16, ZSTD_lazy2   },  /* level  8 */
-    { 21, 20, 20,  3,  5, 16, ZSTD_lazy2   },  /* level  9 */
+    { 21, 19, 20,  3,  5, 16, ZSTD_lazy2   },  /* level  9 */
     { 21, 19, 21,  4,  5, 16, ZSTD_lazy2   },  /* level 10 */
     { 22, 20, 22,  4,  5, 16, ZSTD_lazy2   },  /* level 11 */
     { 22, 20, 22,  5,  5, 16, ZSTD_lazy2   },  /* level 12 */
     { 22, 21, 22,  5,  5, 16, ZSTD_lazy2   },  /* level 13 */
     { 22, 21, 22,  6,  5, 16, ZSTD_lazy2   },  /* level 14 */
-    { 22, 21, 21,  5,  5, 16, ZSTD_btlazy2 },  /* level 15 */
+    { 22, 21, 22,  5,  5, 16, ZSTD_btlazy2 },  /* level 15 */
     { 23, 22, 22,  5,  5, 16, ZSTD_btlazy2 },  /* level 16 */
-    { 23, 21, 22,  4,  5, 24, ZSTD_btopt   },  /* level 17 */
+    { 23, 22, 22,  4,  5, 24, ZSTD_btopt   },  /* level 17 */
     { 23, 22, 22,  5,  4, 32, ZSTD_btopt   },  /* level 18 */
     { 23, 23, 22,  6,  3, 48, ZSTD_btopt   },  /* level 19 */
-    { 25, 25, 23,  7,  3, 64, ZSTD_btopt2  },  /* level 20 */
-    { 26, 26, 23,  7,  3,256, ZSTD_btopt2  },  /* level 21 */
-    { 27, 27, 25,  9,  3,512, ZSTD_btopt2  },  /* level 22 */
+    { 25, 25, 23,  7,  3, 64, ZSTD_btultra },  /* level 20 */
+    { 26, 26, 24,  7,  3,256, ZSTD_btultra },  /* level 21 */
+    { 27, 27, 25,  9,  3,512, ZSTD_btultra },  /* level 22 */
 },
 {   /* for srcSize <= 256 KB */
     /* W,  C,  H,  S,  L,  T, strat */
@@ -3507,9 +4082,9 @@ static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEV
     { 18, 19, 18,  8,  3, 64, ZSTD_btopt   },  /* level 17.*/
     { 18, 19, 18,  9,  3,128, ZSTD_btopt   },  /* level 18.*/
     { 18, 19, 18, 10,  3,256, ZSTD_btopt   },  /* level 19.*/
-    { 18, 19, 18, 11,  3,512, ZSTD_btopt2  },  /* level 20.*/
-    { 18, 19, 18, 12,  3,512, ZSTD_btopt2  },  /* level 21.*/
-    { 18, 19, 18, 13,  3,512, ZSTD_btopt2  },  /* level 22.*/
+    { 18, 19, 18, 11,  3,512, ZSTD_btultra },  /* level 20.*/
+    { 18, 19, 18, 12,  3,512, ZSTD_btultra },  /* level 21.*/
+    { 18, 19, 18, 13,  3,512, ZSTD_btultra },  /* level 22.*/
 },
 {   /* for srcSize <= 128 KB */
     /* W,  C,  H,  S,  L,  T, strat */
@@ -3533,9 +4108,9 @@ static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEV
     { 17, 18, 17,  7,  3, 64, ZSTD_btopt   },  /* level 17.*/
     { 17, 18, 17,  7,  3,256, ZSTD_btopt   },  /* level 18.*/
     { 17, 18, 17,  8,  3,256, ZSTD_btopt   },  /* level 19.*/
-    { 17, 18, 17,  9,  3,256, ZSTD_btopt2  },  /* level 20.*/
-    { 17, 18, 17, 10,  3,256, ZSTD_btopt2  },  /* level 21.*/
-    { 17, 18, 17, 11,  3,512, ZSTD_btopt2  },  /* level 22.*/
+    { 17, 18, 17,  9,  3,256, ZSTD_btultra },  /* level 20.*/
+    { 17, 18, 17, 10,  3,256, ZSTD_btultra },  /* level 21.*/
+    { 17, 18, 17, 11,  3,512, ZSTD_btultra },  /* level 22.*/
 },
 {   /* for srcSize <= 16 KB */
     /* W,  C,  H,  S,  L,  T, strat */
@@ -3559,39 +4134,59 @@ static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEV
     { 14, 15, 15,  6,  3,128, ZSTD_btopt   },  /* level 17.*/
     { 14, 15, 15,  6,  3,256, ZSTD_btopt   },  /* level 18.*/
     { 14, 15, 15,  7,  3,256, ZSTD_btopt   },  /* level 19.*/
-    { 14, 15, 15,  8,  3,256, ZSTD_btopt2  },  /* level 20.*/
-    { 14, 15, 15,  9,  3,256, ZSTD_btopt2  },  /* level 21.*/
-    { 14, 15, 15, 10,  3,256, ZSTD_btopt2  },  /* level 22.*/
+    { 14, 15, 15,  8,  3,256, ZSTD_btultra },  /* level 20.*/
+    { 14, 15, 15,  9,  3,256, ZSTD_btultra },  /* level 21.*/
+    { 14, 15, 15, 10,  3,256, ZSTD_btultra },  /* level 22.*/
 },
 };
 
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
+/* This function just controls
+ * the monotonic memory budget increase of ZSTD_defaultCParameters[0].
+ * Run once, on first ZSTD_getCParams() usage, if ZSTD_DEBUG is enabled
+ */
+MEM_STATIC void ZSTD_check_compressionLevel_monotonicIncrease_memoryBudget(void)
+{
+    int level;
+    for (level=1; level<ZSTD_maxCLevel(); level++) {
+        ZSTD_compressionParameters const c1 = ZSTD_defaultCParameters[0][level];
+        ZSTD_compressionParameters const c2 = ZSTD_defaultCParameters[0][level+1];
+        assert(c1.windowLog <= c2.windowLog);
+#       define ZSTD_TABLECOST(h,c) ((1<<(h)) + (1<<(c)))
+        assert(ZSTD_TABLECOST(c1.hashLog, c1.chainLog) <= ZSTD_TABLECOST(c2.hashLog, c2.chainLog));
+    }
+}
+#endif
+
 /*! ZSTD_getCParams() :
 *   @return ZSTD_compressionParameters structure for a selected compression level, `srcSize` and `dictSize`.
 *   Size values are optional, provide 0 if not known or unused */
-ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long srcSize, size_t dictSize)
+ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long srcSizeHint, size_t dictSize)
 {
-    ZSTD_compressionParameters cp;
-    size_t const addedSize = srcSize ? 0 : 500;
-    U64 const rSize = srcSize+dictSize ? srcSize+dictSize+addedSize : (U64)-1;
+    size_t const addedSize = srcSizeHint ? 0 : 500;
+    U64 const rSize = srcSizeHint+dictSize ? srcSizeHint+dictSize+addedSize : (U64)-1;
     U32 const tableID = (rSize <= 256 KB) + (rSize <= 128 KB) + (rSize <= 16 KB);   /* intentional underflow for srcSizeHint == 0 */
-    if (compressionLevel <= 0) compressionLevel = ZSTD_DEFAULT_CLEVEL;   /* 0 == default; no negative compressionLevel yet */
-    if (compressionLevel > ZSTD_MAX_CLEVEL) compressionLevel = ZSTD_MAX_CLEVEL;
-    cp = ZSTD_defaultCParameters[tableID][compressionLevel];
-    if (MEM_32bits()) {   /* auto-correction, for 32-bits mode */
-        if (cp.windowLog > ZSTD_WINDOWLOG_MAX) cp.windowLog = ZSTD_WINDOWLOG_MAX;
-        if (cp.chainLog > ZSTD_CHAINLOG_MAX) cp.chainLog = ZSTD_CHAINLOG_MAX;
-        if (cp.hashLog > ZSTD_HASHLOG_MAX) cp.hashLog = ZSTD_HASHLOG_MAX;
+
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
+    static int g_monotonicTest = 1;
+    if (g_monotonicTest) {
+        ZSTD_check_compressionLevel_monotonicIncrease_memoryBudget();
+        g_monotonicTest=0;
     }
-    cp = ZSTD_adjustCParams(cp, srcSize, dictSize);
-    return cp;
+#endif
+
+    if (compressionLevel <= 0) compressionLevel = ZSTD_CLEVEL_DEFAULT;   /* 0 == default; no negative compressionLevel yet */
+    if (compressionLevel > ZSTD_MAX_CLEVEL) compressionLevel = ZSTD_MAX_CLEVEL;
+    { ZSTD_compressionParameters const cp = ZSTD_defaultCParameters[tableID][compressionLevel];
+      return ZSTD_adjustCParams_internal(cp, srcSizeHint, dictSize); }
 }
 
 /*! ZSTD_getParams() :
 *   same as ZSTD_getCParams(), but @return a `ZSTD_parameters` object (instead of `ZSTD_compressionParameters`).
 *   All fields of `ZSTD_frameParameters` are set to default (0) */
-ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long srcSize, size_t dictSize) {
+ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long srcSizeHint, size_t dictSize) {
     ZSTD_parameters params;
-    ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, srcSize, dictSize);
+    ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, srcSizeHint, dictSize);
     memset(&params, 0, sizeof(params));
     params.cParams = cParams;
     return params;
diff --git a/lib/compress/zstd_opt.h b/lib/compress/zstd_opt.h
index 54376119121d..e8e98915ea31 100644
--- a/lib/compress/zstd_opt.h
+++ b/lib/compress/zstd_opt.h
@@ -43,6 +43,7 @@ MEM_STATIC void ZSTD_rescaleFreqs(seqStore_t* ssPtr, const BYTE* src, size_t src
     if (ssPtr->litLengthSum == 0) {
         if (srcSize <= 1024) ssPtr->staticPrices = 1;
 
+        assert(ssPtr->litFreq!=NULL);
         for (u=0; u<=MaxLit; u++)
             ssPtr->litFreq[u] = 0;
         for (u=0; u<srcSize; u++)
@@ -201,6 +202,20 @@ MEM_STATIC void ZSTD_updatePrice(seqStore_t* seqStorePtr, U32 litLength, const B
     }
 
 
+/* function safe only for comparisons */
+MEM_STATIC U32 ZSTD_readMINMATCH(const void* memPtr, U32 length)
+{
+    switch (length)
+    {
+    default :
+    case 4 : return MEM_read32(memPtr);
+    case 3 : if (MEM_isLittleEndian())
+                return MEM_read32(memPtr)<<8;
+             else
+                return MEM_read32(memPtr)>>8;
+    }
+}
+
 
 /* Update hashTable3 up to ip (excluded)
    Assumption : always within prefix (i.e. not within extDict) */
@@ -234,12 +249,12 @@ static U32 ZSTD_insertBtAndGetAllMatches (
 {
     const BYTE* const base = zc->base;
     const U32 current = (U32)(ip-base);
-    const U32 hashLog = zc->params.cParams.hashLog;
+    const U32 hashLog = zc->appliedParams.cParams.hashLog;
     const size_t h  = ZSTD_hashPtr(ip, hashLog, mls);
     U32* const hashTable = zc->hashTable;
     U32 matchIndex  = hashTable[h];
     U32* const bt   = zc->chainTable;
-    const U32 btLog = zc->params.cParams.chainLog - 1;
+    const U32 btLog = zc->appliedParams.cParams.chainLog - 1;
     const U32 btMask= (1U << btLog) - 1;
     size_t commonLengthSmaller=0, commonLengthLarger=0;
     const BYTE* const dictBase = zc->dictBase;
@@ -267,7 +282,7 @@ static U32 ZSTD_insertBtAndGetAllMatches (
                 if (match[bestLength] == ip[bestLength]) currentMl = ZSTD_count(ip, match, iLimit);
             } else {
                 match = dictBase + matchIndex3;
-                if (MEM_readMINMATCH(match, MINMATCH) == MEM_readMINMATCH(ip, MINMATCH))    /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */
+                if (ZSTD_readMINMATCH(match, MINMATCH) == ZSTD_readMINMATCH(ip, MINMATCH))    /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */
                     currentMl = ZSTD_count_2segments(ip+MINMATCH, match+MINMATCH, iLimit, dictEnd, prefixStart) + MINMATCH;
             }
 
@@ -410,10 +425,10 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
     const BYTE* const base = ctx->base;
     const BYTE* const prefixStart = base + ctx->dictLimit;
 
-    const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
-    const U32 sufficient_len = ctx->params.cParams.targetLength;
-    const U32 mls = ctx->params.cParams.searchLength;
-    const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
+    const U32 maxSearches = 1U << ctx->appliedParams.cParams.searchLog;
+    const U32 sufficient_len = ctx->appliedParams.cParams.targetLength;
+    const U32 mls = ctx->appliedParams.cParams.searchLength;
+    const U32 minMatch = (ctx->appliedParams.cParams.searchLength == 3) ? 3 : 4;
 
     ZSTD_optimal_t* opt = seqStorePtr->priceTable;
     ZSTD_match_t* matches = seqStorePtr->matchTable;
@@ -439,7 +454,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
             for (i=(ip == anchor); i<last_i; i++) {
                 const S32 repCur = (i==ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i];
                 if ( (repCur > 0) && (repCur < (S32)(ip-prefixStart))
-                    && (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(ip - repCur, minMatch))) {
+                    && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(ip - repCur, minMatch))) {
                     mlen = (U32)ZSTD_count(ip+minMatch, ip+minMatch-repCur, iend) + minMatch;
                     if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
                         best_mlen = mlen; best_off = i; cur = 0; last_pos = 1;
@@ -524,7 +539,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
                 for (i=(opt[cur].mlen != 1); i<last_i; i++) {  /* check rep */
                     const S32 repCur = (i==ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i];
                     if ( (repCur > 0) && (repCur < (S32)(inr-prefixStart))
-                       && (MEM_readMINMATCH(inr, minMatch) == MEM_readMINMATCH(inr - repCur, minMatch))) {
+                       && (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(inr - repCur, minMatch))) {
                        mlen = (U32)ZSTD_count(inr+minMatch, inr+minMatch - repCur, iend) + minMatch;
 
                        if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
@@ -663,10 +678,10 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
     const BYTE* const dictBase = ctx->dictBase;
     const BYTE* const dictEnd  = dictBase + dictLimit;
 
-    const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
-    const U32 sufficient_len = ctx->params.cParams.targetLength;
-    const U32 mls = ctx->params.cParams.searchLength;
-    const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
+    const U32 maxSearches = 1U << ctx->appliedParams.cParams.searchLog;
+    const U32 sufficient_len = ctx->appliedParams.cParams.targetLength;
+    const U32 mls = ctx->appliedParams.cParams.searchLength;
+    const U32 minMatch = (ctx->appliedParams.cParams.searchLength == 3) ? 3 : 4;
 
     ZSTD_optimal_t* opt = seqStorePtr->priceTable;
     ZSTD_match_t* matches = seqStorePtr->matchTable;
@@ -698,7 +713,7 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
                 const BYTE* const repMatch = repBase + repIndex;
                 if ( (repCur > 0 && repCur <= (S32)current)
                    && (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex>lowestIndex))  /* intentional overflow */
-                   && (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(repMatch, minMatch)) ) {
+                   && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch)) ) {
                     /* repcode detected we should take it */
                     const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
                     mlen = (U32)ZSTD_count_2segments(ip+minMatch, repMatch+minMatch, iend, repEnd, prefixStart) + minMatch;
@@ -794,7 +809,7 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
                     const BYTE* const repMatch = repBase + repIndex;
                     if ( (repCur > 0 && repCur <= (S32)(current+cur))
                       && (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex>lowestIndex))  /* intentional overflow */
-                      && (MEM_readMINMATCH(inr, minMatch) == MEM_readMINMATCH(repMatch, minMatch)) ) {
+                      && (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch)) ) {
                         /* repcode detected */
                         const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
                         mlen = (U32)ZSTD_count_2segments(inr+minMatch, repMatch+minMatch, iend, repEnd, prefixStart) + minMatch;
diff --git a/lib/compress/zstdmt_compress.c b/lib/compress/zstdmt_compress.c
index fc7f52a2902d..0cee01eacb86 100644
--- a/lib/compress/zstdmt_compress.c
+++ b/lib/compress/zstdmt_compress.c
@@ -14,34 +14,31 @@
 
 /* ======   Compiler specifics   ====== */
 #if defined(_MSC_VER)
-#  pragma warning(disable : 4204)        /* disable: C4204: non-constant aggregate initializer */
+#  pragma warning(disable : 4204)   /* disable: C4204: non-constant aggregate initializer */
 #endif
 
 
 /* ======   Dependencies   ====== */
-#include <stdlib.h>   /* malloc */
-#include <string.h>   /* memcpy */
-#include "pool.h"     /* threadpool */
-#include "threading.h"  /* mutex */
-#include "zstd_internal.h"   /* MIN, ERROR, ZSTD_*, ZSTD_highbit32 */
+#include <string.h>      /* memcpy, memset */
+#include "pool.h"        /* threadpool */
+#include "threading.h"   /* mutex */
+#include "zstd_internal.h"  /* MIN, ERROR, ZSTD_*, ZSTD_highbit32 */
 #include "zstdmt_compress.h"
 
 
 /* ======   Debug   ====== */
-#if 0
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=2)
 
 #  include <stdio.h>
 #  include <unistd.h>
 #  include <sys/times.h>
-   static unsigned g_debugLevel = 5;
-#  define DEBUGLOGRAW(l, ...) if (l<=g_debugLevel) { fprintf(stderr, __VA_ARGS__); }
-#  define DEBUGLOG(l, ...) if (l<=g_debugLevel) { fprintf(stderr, __FILE__ ": "); fprintf(stderr, __VA_ARGS__); fprintf(stderr, " \n"); }
+#  define DEBUGLOGRAW(l, ...) if (l<=ZSTD_DEBUG) { fprintf(stderr, __VA_ARGS__); }
 
-#  define DEBUG_PRINTHEX(l,p,n) { \
-    unsigned debug_u;                   \
-    for (debug_u=0; debug_u<(n); debug_u++)           \
+#  define DEBUG_PRINTHEX(l,p,n) {            \
+    unsigned debug_u;                        \
+    for (debug_u=0; debug_u<(n); debug_u++)  \
         DEBUGLOGRAW(l, "%02X ", ((const unsigned char*)(p))[debug_u]); \
-    DEBUGLOGRAW(l, " \n");       \
+    DEBUGLOGRAW(l, " \n");                   \
 }
 
 static unsigned long long GetCurrentClockTimeMicroseconds(void)
@@ -53,22 +50,22 @@ static unsigned long long GetCurrentClockTimeMicroseconds(void)
      return ((((unsigned long long)newTicks)*(1000000))/_ticksPerSecond); }
 }
 
-#define MUTEX_WAIT_TIME_DLEVEL 5
-#define PTHREAD_MUTEX_LOCK(mutex) \
-if (g_debugLevel>=MUTEX_WAIT_TIME_DLEVEL) { \
-    unsigned long long const beforeTime = GetCurrentClockTimeMicroseconds(); \
-    pthread_mutex_lock(mutex); \
-    {   unsigned long long const afterTime = GetCurrentClockTimeMicroseconds(); \
-        unsigned long long const elapsedTime = (afterTime-beforeTime); \
-        if (elapsedTime > 1000) {  /* or whatever threshold you like; I'm using 1 millisecond here */ \
-            DEBUGLOG(MUTEX_WAIT_TIME_DLEVEL, "Thread took %llu microseconds to acquire mutex %s \n", \
-               elapsedTime, #mutex); \
-    }   } \
-} else pthread_mutex_lock(mutex);
+#define MUTEX_WAIT_TIME_DLEVEL 6
+#define PTHREAD_MUTEX_LOCK(mutex) {               \
+    if (ZSTD_DEBUG>=MUTEX_WAIT_TIME_DLEVEL) {   \
+        unsigned long long const beforeTime = GetCurrentClockTimeMicroseconds(); \
+        pthread_mutex_lock(mutex);                \
+        {   unsigned long long const afterTime = GetCurrentClockTimeMicroseconds(); \
+            unsigned long long const elapsedTime = (afterTime-beforeTime); \
+            if (elapsedTime > 1000) {  /* or whatever threshold you like; I'm using 1 millisecond here */ \
+                DEBUGLOG(MUTEX_WAIT_TIME_DLEVEL, "Thread took %llu microseconds to acquire mutex %s \n", \
+                   elapsedTime, #mutex);          \
+        }   }                                     \
+    } else pthread_mutex_lock(mutex);             \
+}
 
 #else
 
-#  define DEBUGLOG(l, ...)      {}    /* disabled */
 #  define PTHREAD_MUTEX_LOCK(m) pthread_mutex_lock(m)
 #  define DEBUG_PRINTHEX(l,p,n) {}
 
@@ -87,16 +84,19 @@ static const buffer_t g_nullBuffer = { NULL, 0 };
 typedef struct ZSTDMT_bufferPool_s {
     unsigned totalBuffers;
     unsigned nbBuffers;
+    ZSTD_customMem cMem;
     buffer_t bTable[1];   /* variable size */
 } ZSTDMT_bufferPool;
 
-static ZSTDMT_bufferPool* ZSTDMT_createBufferPool(unsigned nbThreads)
+static ZSTDMT_bufferPool* ZSTDMT_createBufferPool(unsigned nbThreads, ZSTD_customMem cMem)
 {
     unsigned const maxNbBuffers = 2*nbThreads + 2;
-    ZSTDMT_bufferPool* const bufPool = (ZSTDMT_bufferPool*)calloc(1, sizeof(ZSTDMT_bufferPool) + (maxNbBuffers-1) * sizeof(buffer_t));
+    ZSTDMT_bufferPool* const bufPool = (ZSTDMT_bufferPool*)ZSTD_calloc(
+        sizeof(ZSTDMT_bufferPool) + (maxNbBuffers-1) * sizeof(buffer_t), cMem);
     if (bufPool==NULL) return NULL;
     bufPool->totalBuffers = maxNbBuffers;
     bufPool->nbBuffers = 0;
+    bufPool->cMem = cMem;
     return bufPool;
 }
 
@@ -105,23 +105,39 @@ static void ZSTDMT_freeBufferPool(ZSTDMT_bufferPool* bufPool)
     unsigned u;
     if (!bufPool) return;   /* compatibility with free on NULL */
     for (u=0; u<bufPool->totalBuffers; u++)
-        free(bufPool->bTable[u].start);
-    free(bufPool);
+        ZSTD_free(bufPool->bTable[u].start, bufPool->cMem);
+    ZSTD_free(bufPool, bufPool->cMem);
+}
+
+/* only works at initialization, not during compression */
+static size_t ZSTDMT_sizeof_bufferPool(ZSTDMT_bufferPool* bufPool)
+{
+    size_t const poolSize = sizeof(*bufPool)
+                            + (bufPool->totalBuffers - 1) * sizeof(buffer_t);
+    unsigned u;
+    size_t totalBufferSize = 0;
+    for (u=0; u<bufPool->totalBuffers; u++)
+        totalBufferSize += bufPool->bTable[u].size;
+
+    return poolSize + totalBufferSize;
 }
 
-/* assumption : invocation from main thread only ! */
+/** ZSTDMT_getBuffer() :
+ *  assumption : invocation from main thread only ! */
 static buffer_t ZSTDMT_getBuffer(ZSTDMT_bufferPool* pool, size_t bSize)
 {
     if (pool->nbBuffers) {   /* try to use an existing buffer */
         buffer_t const buf = pool->bTable[--(pool->nbBuffers)];
         size_t const availBufferSize = buf.size;
-        if ((availBufferSize >= bSize) & (availBufferSize <= 10*bSize))   /* large enough, but not too much */
+        if ((availBufferSize >= bSize) & (availBufferSize <= 10*bSize))
+            /* large enough, but not too much */
             return buf;
-        free(buf.start);   /* size conditions not respected : scratch this buffer and create a new one */
+        /* size conditions not respected : scratch this buffer, create new one */
+        ZSTD_free(buf.start, pool->cMem);
     }
     /* create new buffer */
     {   buffer_t buffer;
-        void* const start = malloc(bSize);
+        void* const start = ZSTD_malloc(bSize, pool->cMem);
         if (start==NULL) bSize = 0;
         buffer.start = start;   /* note : start can be NULL if malloc fails ! */
         buffer.size = bSize;
@@ -138,7 +154,7 @@ static void ZSTDMT_releaseBuffer(ZSTDMT_bufferPool* pool, buffer_t buf)
         return;
     }
     /* Reached bufferPool capacity (should not happen) */
-    free(buf.start);
+    ZSTD_free(buf.start, pool->cMem);
 }
 
 
@@ -147,6 +163,7 @@ static void ZSTDMT_releaseBuffer(ZSTDMT_bufferPool* pool, buffer_t buf)
 typedef struct {
     unsigned totalCCtx;
     unsigned availCCtx;
+    ZSTD_customMem cMem;
     ZSTD_CCtx* cctx[1];   /* variable size */
 } ZSTDMT_CCtxPool;
 
@@ -158,23 +175,40 @@ static void ZSTDMT_freeCCtxPool(ZSTDMT_CCtxPool* pool)
     unsigned u;
     for (u=0; u<pool->totalCCtx; u++)
         ZSTD_freeCCtx(pool->cctx[u]);  /* note : compatible with free on NULL */
-    free(pool);
+    ZSTD_free(pool, pool->cMem);
 }
 
 /* ZSTDMT_createCCtxPool() :
  * implies nbThreads >= 1 , checked by caller ZSTDMT_createCCtx() */
-static ZSTDMT_CCtxPool* ZSTDMT_createCCtxPool(unsigned nbThreads)
+static ZSTDMT_CCtxPool* ZSTDMT_createCCtxPool(unsigned nbThreads,
+                                              ZSTD_customMem cMem)
 {
-    ZSTDMT_CCtxPool* const cctxPool = (ZSTDMT_CCtxPool*) calloc(1, sizeof(ZSTDMT_CCtxPool) + (nbThreads-1)*sizeof(ZSTD_CCtx*));
+    ZSTDMT_CCtxPool* const cctxPool = (ZSTDMT_CCtxPool*) ZSTD_calloc(
+        sizeof(ZSTDMT_CCtxPool) + (nbThreads-1)*sizeof(ZSTD_CCtx*), cMem);
     if (!cctxPool) return NULL;
+    cctxPool->cMem = cMem;
     cctxPool->totalCCtx = nbThreads;
     cctxPool->availCCtx = 1;   /* at least one cctx for single-thread mode */
-    cctxPool->cctx[0] = ZSTD_createCCtx();
+    cctxPool->cctx[0] = ZSTD_createCCtx_advanced(cMem);
     if (!cctxPool->cctx[0]) { ZSTDMT_freeCCtxPool(cctxPool); return NULL; }
-    DEBUGLOG(1, "cctxPool created, with %u threads", nbThreads);
+    DEBUGLOG(3, "cctxPool created, with %u threads", nbThreads);
     return cctxPool;
 }
 
+/* only works during initialization phase, not during compression */
+static size_t ZSTDMT_sizeof_CCtxPool(ZSTDMT_CCtxPool* cctxPool)
+{
+    unsigned const nbThreads = cctxPool->totalCCtx;
+    size_t const poolSize = sizeof(*cctxPool)
+                            + (nbThreads-1)*sizeof(ZSTD_CCtx*);
+    unsigned u;
+    size_t totalCCtxSize = 0;
+    for (u=0; u<nbThreads; u++)
+        totalCCtxSize += ZSTD_sizeof_CCtx(cctxPool->cctx[u]);
+
+    return poolSize + totalCCtxSize;
+}
+
 static ZSTD_CCtx* ZSTDMT_getCCtx(ZSTDMT_CCtxPool* pool)
 {
     if (pool->availCCtx) {
@@ -218,7 +252,7 @@ typedef struct {
     pthread_mutex_t* jobCompleted_mutex;
     pthread_cond_t* jobCompleted_cond;
     ZSTD_parameters params;
-    ZSTD_CDict* cdict;
+    const ZSTD_CDict* cdict;
     unsigned long long fullFrameSize;
 } ZSTDMT_jobDescription;
 
@@ -228,11 +262,11 @@ void ZSTDMT_compressChunk(void* jobDescription)
     ZSTDMT_jobDescription* const job = (ZSTDMT_jobDescription*)jobDescription;
     const void* const src = (const char*)job->srcStart + job->dictSize;
     buffer_t const dstBuff = job->dstBuff;
-    DEBUGLOG(3, "job (first:%u) (last:%u) : dictSize %u, srcSize %u",
+    DEBUGLOG(5, "job (first:%u) (last:%u) : dictSize %u, srcSize %u",
                  job->firstChunk, job->lastChunk, (U32)job->dictSize, (U32)job->srcSize);
     if (job->cdict) {  /* should only happen for first segment */
         size_t const initError = ZSTD_compressBegin_usingCDict_advanced(job->cctx, job->cdict, job->params.fParams, job->fullFrameSize);
-        if (job->cdict) DEBUGLOG(3, "using CDict ");
+        DEBUGLOG(5, "using CDict");
         if (ZSTD_isError(initError)) { job->cSize = initError; goto _endJob; }
     } else {  /* srcStart points at reloaded section */
         if (!job->firstChunk) job->params.fParams.contentSizeFlag = 0;  /* ensure no srcSize control */
@@ -247,12 +281,12 @@ void ZSTDMT_compressChunk(void* jobDescription)
         ZSTD_invalidateRepCodes(job->cctx);
     }
 
-    DEBUGLOG(4, "Compressing : ");
+    DEBUGLOG(5, "Compressing : ");
     DEBUG_PRINTHEX(4, job->srcStart, 12);
     job->cSize = (job->lastChunk) ?
                  ZSTD_compressEnd     (job->cctx, dstBuff.start, dstBuff.size, src, job->srcSize) :
                  ZSTD_compressContinue(job->cctx, dstBuff.start, dstBuff.size, src, job->srcSize);
-    DEBUGLOG(3, "compressed %u bytes into %u bytes   (first:%u) (last:%u)",
+    DEBUGLOG(5, "compressed %u bytes into %u bytes   (first:%u) (last:%u)",
                 (unsigned)job->srcSize, (unsigned)job->cSize, job->firstChunk, job->lastChunk);
     DEBUGLOG(5, "dstBuff.size : %u ; => %s", (U32)dstBuff.size, ZSTD_getErrorName(job->cSize));
 
@@ -271,6 +305,7 @@ _endJob:
 
 struct ZSTDMT_CCtx_s {
     POOL_ctx* factory;
+    ZSTDMT_jobDescription* jobs;
     ZSTDMT_bufferPool* buffPool;
     ZSTDMT_CCtxPool* cctxPool;
     pthread_mutex_t jobCompleted_mutex;
@@ -292,50 +327,64 @@ struct ZSTDMT_CCtx_s {
     unsigned overlapRLog;
     unsigned long long frameContentSize;
     size_t sectionSize;
-    ZSTD_CDict* cdict;
-    ZSTD_CStream* cstream;
-    ZSTDMT_jobDescription jobs[1];   /* variable size (must lies at the end) */
+    ZSTD_customMem cMem;
+    ZSTD_CDict* cdictLocal;
+    const ZSTD_CDict* cdict;
 };
 
-ZSTDMT_CCtx *ZSTDMT_createCCtx(unsigned nbThreads)
+static ZSTDMT_jobDescription* ZSTDMT_allocJobsTable(U32* nbJobsPtr, ZSTD_customMem cMem)
 {
-    ZSTDMT_CCtx* cctx;
-    U32 const minNbJobs = nbThreads + 2;
-    U32 const nbJobsLog2 = ZSTD_highbit32(minNbJobs) + 1;
+    U32 const nbJobsLog2 = ZSTD_highbit32(*nbJobsPtr) + 1;
     U32 const nbJobs = 1 << nbJobsLog2;
-    DEBUGLOG(5, "nbThreads : %u  ; minNbJobs : %u ;  nbJobsLog2 : %u ;  nbJobs : %u  \n",
-            nbThreads, minNbJobs, nbJobsLog2, nbJobs);
+    *nbJobsPtr = nbJobs;
+    return (ZSTDMT_jobDescription*) ZSTD_calloc(
+                            nbJobs * sizeof(ZSTDMT_jobDescription), cMem);
+}
+
+ZSTDMT_CCtx* ZSTDMT_createCCtx_advanced(unsigned nbThreads, ZSTD_customMem cMem)
+{
+    ZSTDMT_CCtx* mtctx;
+    U32 nbJobs = nbThreads + 2;
+    DEBUGLOG(3, "ZSTDMT_createCCtx_advanced");
+
     if ((nbThreads < 1) | (nbThreads > ZSTDMT_NBTHREADS_MAX)) return NULL;
-    cctx = (ZSTDMT_CCtx*) calloc(1, sizeof(ZSTDMT_CCtx) + nbJobs*sizeof(ZSTDMT_jobDescription));
-    if (!cctx) return NULL;
-    cctx->nbThreads = nbThreads;
-    cctx->jobIDMask = nbJobs - 1;
-    cctx->allJobsCompleted = 1;
-    cctx->sectionSize = 0;
-    cctx->overlapRLog = 3;
-    cctx->factory = POOL_create(nbThreads, 1);
-    cctx->buffPool = ZSTDMT_createBufferPool(nbThreads);
-    cctx->cctxPool = ZSTDMT_createCCtxPool(nbThreads);
-    if (!cctx->factory | !cctx->buffPool | !cctx->cctxPool) {  /* one object was not created */
-        ZSTDMT_freeCCtx(cctx);
+    if ((cMem.customAlloc!=NULL) ^ (cMem.customFree!=NULL))
+        /* invalid custom allocator */
+        return NULL;
+
+    mtctx = (ZSTDMT_CCtx*) ZSTD_calloc(sizeof(ZSTDMT_CCtx), cMem);
+    if (!mtctx) return NULL;
+    mtctx->cMem = cMem;
+    mtctx->nbThreads = nbThreads;
+    mtctx->allJobsCompleted = 1;
+    mtctx->sectionSize = 0;
+    mtctx->overlapRLog = 3;
+    mtctx->factory = POOL_create(nbThreads, 1);
+    mtctx->jobs = ZSTDMT_allocJobsTable(&nbJobs, cMem);
+    mtctx->jobIDMask = nbJobs - 1;
+    mtctx->buffPool = ZSTDMT_createBufferPool(nbThreads, cMem);
+    mtctx->cctxPool = ZSTDMT_createCCtxPool(nbThreads, cMem);
+    if (!mtctx->factory | !mtctx->jobs | !mtctx->buffPool | !mtctx->cctxPool) {
+        ZSTDMT_freeCCtx(mtctx);
         return NULL;
     }
-    if (nbThreads==1) {
-        cctx->cstream = ZSTD_createCStream();
-        if (!cctx->cstream) {
-            ZSTDMT_freeCCtx(cctx); return NULL;
-    }   }
-    pthread_mutex_init(&cctx->jobCompleted_mutex, NULL);   /* Todo : check init function return */
-    pthread_cond_init(&cctx->jobCompleted_cond, NULL);
-    DEBUGLOG(4, "mt_cctx created, for %u threads \n", nbThreads);
-    return cctx;
+    pthread_mutex_init(&mtctx->jobCompleted_mutex, NULL);   /* Todo : check init function return */
+    pthread_cond_init(&mtctx->jobCompleted_cond, NULL);
+    DEBUGLOG(3, "mt_cctx created, for %u threads", nbThreads);
+    return mtctx;
+}
+
+ZSTDMT_CCtx* ZSTDMT_createCCtx(unsigned nbThreads)
+{
+    return ZSTDMT_createCCtx_advanced(nbThreads, ZSTD_defaultCMem);
 }
 
 /* ZSTDMT_releaseAllJobResources() :
- * Ensure all workers are killed first. */
+ * note : ensure all workers are killed first ! */
 static void ZSTDMT_releaseAllJobResources(ZSTDMT_CCtx* mtctx)
 {
     unsigned jobID;
+    DEBUGLOG(3, "ZSTDMT_releaseAllJobResources");
     for (jobID=0; jobID <= mtctx->jobIDMask; jobID++) {
         ZSTDMT_releaseBuffer(mtctx->buffPool, mtctx->jobs[jobID].dstBuff);
         mtctx->jobs[jobID].dstBuff = g_nullBuffer;
@@ -356,15 +405,26 @@ size_t ZSTDMT_freeCCtx(ZSTDMT_CCtx* mtctx)
     POOL_free(mtctx->factory);
     if (!mtctx->allJobsCompleted) ZSTDMT_releaseAllJobResources(mtctx); /* stop workers first */
     ZSTDMT_freeBufferPool(mtctx->buffPool);  /* release job resources into pools first */
+    ZSTD_free(mtctx->jobs, mtctx->cMem);
     ZSTDMT_freeCCtxPool(mtctx->cctxPool);
-    ZSTD_freeCDict(mtctx->cdict);
-    ZSTD_freeCStream(mtctx->cstream);
+    ZSTD_freeCDict(mtctx->cdictLocal);
     pthread_mutex_destroy(&mtctx->jobCompleted_mutex);
     pthread_cond_destroy(&mtctx->jobCompleted_cond);
-    free(mtctx);
+    ZSTD_free(mtctx, mtctx->cMem);
     return 0;
 }
 
+size_t ZSTDMT_sizeof_CCtx(ZSTDMT_CCtx* mtctx)
+{
+    if (mtctx == NULL) return 0;   /* supports sizeof NULL */
+    return sizeof(*mtctx)
+        + POOL_sizeof(mtctx->factory)
+        + ZSTDMT_sizeof_bufferPool(mtctx->buffPool)
+        + (mtctx->jobIDMask+1) * sizeof(ZSTDMT_jobDescription)
+        + ZSTDMT_sizeof_CCtxPool(mtctx->cctxPool)
+        + ZSTD_sizeof_CDict(mtctx->cdictLocal);
+}
+
 size_t ZSTDMT_setMTCtxParameter(ZSTDMT_CCtx* mtctx, ZSDTMT_parameter parameter, unsigned value)
 {
     switch(parameter)
@@ -373,7 +433,7 @@ size_t ZSTDMT_setMTCtxParameter(ZSTDMT_CCtx* mtctx, ZSDTMT_parameter parameter,
         mtctx->sectionSize = value;
         return 0;
     case ZSTDMT_p_overlapSectionLog :
-    DEBUGLOG(4, "ZSTDMT_p_overlapSectionLog : %u", value);
+        DEBUGLOG(5, "ZSTDMT_p_overlapSectionLog : %u", value);
         mtctx->overlapRLog = (value >= 9) ? 0 : 9 - value;
         return 0;
     default :
@@ -386,31 +446,49 @@ size_t ZSTDMT_setMTCtxParameter(ZSTDMT_CCtx* mtctx, ZSDTMT_parameter parameter,
 /* =====   Multi-threaded compression   ===== */
 /* ------------------------------------------ */
 
-size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
+static unsigned computeNbChunks(size_t srcSize, unsigned windowLog, unsigned nbThreads) {
+    size_t const chunkSizeTarget = (size_t)1 << (windowLog + 2);
+    size_t const chunkMaxSize = chunkSizeTarget << 2;
+    size_t const passSizeMax = chunkMaxSize * nbThreads;
+    unsigned const multiplier = (unsigned)(srcSize / passSizeMax) + 1;
+    unsigned const nbChunksLarge = multiplier * nbThreads;
+    unsigned const nbChunksMax = (unsigned)(srcSize / chunkSizeTarget) + 1;
+    unsigned const nbChunksSmall = MIN(nbChunksMax, nbThreads);
+    return (multiplier>1) ? nbChunksLarge : nbChunksSmall;
+}
+
+
+size_t ZSTDMT_compress_advanced(ZSTDMT_CCtx* mtctx,
                            void* dst, size_t dstCapacity,
                      const void* src, size_t srcSize,
-                           int compressionLevel)
+                     const ZSTD_CDict* cdict,
+                           ZSTD_parameters const params,
+                           unsigned overlapRLog)
 {
-    ZSTD_parameters params = ZSTD_getParams(compressionLevel, srcSize, 0);
-    U32 const overlapLog = (compressionLevel >= ZSTD_maxCLevel()) ? 0 : 3;
-    size_t const overlapSize = (size_t)1 << (params.cParams.windowLog - overlapLog);
-    size_t const chunkTargetSize = (size_t)1 << (params.cParams.windowLog + 2);
-    unsigned const nbChunksMax = (unsigned)(srcSize / chunkTargetSize) + 1;
-    unsigned nbChunks = MIN(nbChunksMax, mtctx->nbThreads);
+    size_t const overlapSize = (overlapRLog>=9) ? 0 : (size_t)1 << (params.cParams.windowLog - overlapRLog);
+    unsigned nbChunks = computeNbChunks(srcSize, params.cParams.windowLog, mtctx->nbThreads);
     size_t const proposedChunkSize = (srcSize + (nbChunks-1)) / nbChunks;
-    size_t const avgChunkSize = ((proposedChunkSize & 0x1FFFF) < 0xFFFF) ? proposedChunkSize + 0xFFFF : proposedChunkSize;   /* avoid too small last block */
-    size_t remainingSrcSize = srcSize;
+    size_t const avgChunkSize = ((proposedChunkSize & 0x1FFFF) < 0x7FFF) ? proposedChunkSize + 0xFFFF : proposedChunkSize;   /* avoid too small last block */
     const char* const srcStart = (const char*)src;
+    size_t remainingSrcSize = srcSize;
     unsigned const compressWithinDst = (dstCapacity >= ZSTD_compressBound(srcSize)) ? nbChunks : (unsigned)(dstCapacity / ZSTD_compressBound(avgChunkSize));  /* presumes avgChunkSize >= 256 KB, which should be the case */
     size_t frameStartPos = 0, dstBufferPos = 0;
 
-    DEBUGLOG(3, "windowLog : %2u => chunkTargetSize : %u bytes  ", params.cParams.windowLog, (U32)chunkTargetSize);
-    DEBUGLOG(2, "nbChunks  : %2u   (chunkSize : %u bytes)   ", nbChunks, (U32)avgChunkSize);
-    params.fParams.contentSizeFlag = 1;
-
+    DEBUGLOG(4, "nbChunks  : %2u   (chunkSize : %u bytes)   ", nbChunks, (U32)avgChunkSize);
     if (nbChunks==1) {   /* fallback to single-thread mode */
         ZSTD_CCtx* const cctx = mtctx->cctxPool->cctx[0];
-        return ZSTD_compressCCtx(cctx, dst, dstCapacity, src, srcSize, compressionLevel);
+        if (cdict) return ZSTD_compress_usingCDict_advanced(cctx, dst, dstCapacity, src, srcSize, cdict, params.fParams);
+        return ZSTD_compress_advanced(cctx, dst, dstCapacity, src, srcSize, NULL, 0, params);
+    }
+    assert(avgChunkSize >= 256 KB);  /* condition for ZSTD_compressBound(A) + ZSTD_compressBound(B) <= ZSTD_compressBound(A+B), which is useful to avoid allocating extra buffers */
+
+    if (nbChunks > mtctx->jobIDMask+1) {  /* enlarge job table */
+        U32 nbJobs = nbChunks;
+        ZSTD_free(mtctx->jobs, mtctx->cMem);
+        mtctx->jobIDMask = 0;
+        mtctx->jobs = ZSTDMT_allocJobsTable(&nbJobs, mtctx->cMem);
+        if (mtctx->jobs==NULL) return ERROR(memory_allocation);
+        mtctx->jobIDMask = nbJobs - 1;
     }
 
     {   unsigned u;
@@ -425,15 +503,18 @@ size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
             if ((cctx==NULL) || (dstBuffer.start==NULL)) {
                 mtctx->jobs[u].cSize = ERROR(memory_allocation);   /* job result */
                 mtctx->jobs[u].jobCompleted = 1;
-                nbChunks = u+1;
+                nbChunks = u+1;   /* only wait and free u jobs, instead of initially expected nbChunks ones */
                 break;   /* let's wait for previous jobs to complete, but don't start new ones */
             }
 
             mtctx->jobs[u].srcStart = srcStart + frameStartPos - dictSize;
             mtctx->jobs[u].dictSize = dictSize;
             mtctx->jobs[u].srcSize = chunkSize;
+            mtctx->jobs[u].cdict = mtctx->nextJobID==0 ? cdict : NULL;
             mtctx->jobs[u].fullFrameSize = srcSize;
             mtctx->jobs[u].params = params;
+            /* do not calculate checksum within sections, but write it in header for first section */
+            if (u!=0) mtctx->jobs[u].params.fParams.checksumFlag = 0;
             mtctx->jobs[u].dstBuff = dstBuffer;
             mtctx->jobs[u].cctx = cctx;
             mtctx->jobs[u].firstChunk = (u==0);
@@ -442,27 +523,27 @@ size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
             mtctx->jobs[u].jobCompleted_mutex = &mtctx->jobCompleted_mutex;
             mtctx->jobs[u].jobCompleted_cond = &mtctx->jobCompleted_cond;
 
-            DEBUGLOG(3, "posting job %u   (%u bytes)", u, (U32)chunkSize);
-            DEBUG_PRINTHEX(3, mtctx->jobs[u].srcStart, 12);
+            DEBUGLOG(5, "posting job %u   (%u bytes)", u, (U32)chunkSize);
+            DEBUG_PRINTHEX(6, mtctx->jobs[u].srcStart, 12);
             POOL_add(mtctx->factory, ZSTDMT_compressChunk, &mtctx->jobs[u]);
 
             frameStartPos += chunkSize;
             dstBufferPos += dstBufferCapacity;
             remainingSrcSize -= chunkSize;
     }   }
-    /* note : since nbChunks <= nbThreads, all jobs should be running immediately in parallel */
 
+    /* collect result */
     {   unsigned chunkID;
         size_t error = 0, dstPos = 0;
         for (chunkID=0; chunkID<nbChunks; chunkID++) {
-            DEBUGLOG(3, "waiting for chunk %u ", chunkID);
+            DEBUGLOG(5, "waiting for chunk %u ", chunkID);
             PTHREAD_MUTEX_LOCK(&mtctx->jobCompleted_mutex);
             while (mtctx->jobs[chunkID].jobCompleted==0) {
-                DEBUGLOG(4, "waiting for jobCompleted signal from chunk %u", chunkID);
+                DEBUGLOG(5, "waiting for jobCompleted signal from chunk %u", chunkID);
                 pthread_cond_wait(&mtctx->jobCompleted_cond, &mtctx->jobCompleted_mutex);
             }
             pthread_mutex_unlock(&mtctx->jobCompleted_mutex);
-            DEBUGLOG(3, "ready to write chunk %u ", chunkID);
+            DEBUGLOG(5, "ready to write chunk %u ", chunkID);
 
             ZSTDMT_releaseCCtx(mtctx->cctxPool, mtctx->jobs[chunkID].cctx);
             mtctx->jobs[chunkID].cctx = NULL;
@@ -470,20 +551,33 @@ size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
             {   size_t const cSize = mtctx->jobs[chunkID].cSize;
                 if (ZSTD_isError(cSize)) error = cSize;
                 if ((!error) && (dstPos + cSize > dstCapacity)) error = ERROR(dstSize_tooSmall);
-                if (chunkID) {   /* note : chunk 0 is already written directly into dst */
+                if (chunkID) {   /* note : chunk 0 is written directly at dst, which is correct position */
                     if (!error)
-                        memmove((char*)dst + dstPos, mtctx->jobs[chunkID].dstBuff.start, cSize);  /* may overlap if chunk decompressed within dst */
-                    if (chunkID >= compressWithinDst)   /* otherwise, it decompresses within dst */
+                        memmove((char*)dst + dstPos, mtctx->jobs[chunkID].dstBuff.start, cSize);  /* may overlap when chunk compressed within dst */
+                    if (chunkID >= compressWithinDst) {  /* chunk compressed into its own buffer, which must be released */
+                        DEBUGLOG(5, "releasing buffer %u>=%u", chunkID, compressWithinDst);
                         ZSTDMT_releaseBuffer(mtctx->buffPool, mtctx->jobs[chunkID].dstBuff);
+                    }
                     mtctx->jobs[chunkID].dstBuff = g_nullBuffer;
                 }
                 dstPos += cSize ;
             }
         }
-        if (!error) DEBUGLOG(3, "compressed size : %u  ", (U32)dstPos);
+        if (!error) DEBUGLOG(4, "compressed size : %u  ", (U32)dstPos);
         return error ? error : dstPos;
     }
+}
+
 
+size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
+                           void* dst, size_t dstCapacity,
+                     const void* src, size_t srcSize,
+                           int compressionLevel)
+{
+    U32 const overlapRLog = (compressionLevel >= ZSTD_maxCLevel()) ? 0 : 3;
+    ZSTD_parameters params = ZSTD_getParams(compressionLevel, srcSize, 0);
+    params.fParams.contentSizeFlag = 1;
+    return ZSTDMT_compress_advanced(mtctx, dst, dstCapacity, src, srcSize, NULL, params, overlapRLog);
 }
 
 
@@ -491,12 +585,14 @@ size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
 /* =======      Streaming API     ======= */
 /* ====================================== */
 
-static void ZSTDMT_waitForAllJobsCompleted(ZSTDMT_CCtx* zcs) {
+static void ZSTDMT_waitForAllJobsCompleted(ZSTDMT_CCtx* zcs)
+{
+    DEBUGLOG(4, "ZSTDMT_waitForAllJobsCompleted");
     while (zcs->doneJobID < zcs->nextJobID) {
         unsigned const jobID = zcs->doneJobID & zcs->jobIDMask;
         PTHREAD_MUTEX_LOCK(&zcs->jobCompleted_mutex);
         while (zcs->jobs[jobID].jobCompleted==0) {
-            DEBUGLOG(4, "waiting for jobCompleted signal from chunk %u", zcs->doneJobID);   /* we want to block when waiting for data to flush */
+            DEBUGLOG(5, "waiting for jobCompleted signal from chunk %u", zcs->doneJobID);   /* we want to block when waiting for data to flush */
             pthread_cond_wait(&zcs->jobCompleted_cond, &zcs->jobCompleted_mutex);
         }
         pthread_mutex_unlock(&zcs->jobCompleted_mutex);
@@ -505,33 +601,54 @@ static void ZSTDMT_waitForAllJobsCompleted(ZSTDMT_CCtx* zcs) {
 }
 
 
-static size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
-                                    const void* dict, size_t dictSize, unsigned updateDict,
-                                    ZSTD_parameters params, unsigned long long pledgedSrcSize)
+/** ZSTDMT_initCStream_internal() :
+ *  internal usage only */
+size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
+                    const void* dict, size_t dictSize, const ZSTD_CDict* cdict,
+                    ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
-    ZSTD_customMem const cmem = { NULL, NULL, NULL };
-    DEBUGLOG(3, "Started new compression, with windowLog : %u", params.cParams.windowLog);
-    if (zcs->nbThreads==1) return ZSTD_initCStream_advanced(zcs->cstream, dict, dictSize, params, pledgedSrcSize);
-    if (zcs->allJobsCompleted == 0) {   /* previous job not correctly finished */
+    DEBUGLOG(4, "ZSTDMT_initCStream_internal");
+    /* params are supposed to be fully validated at this point */
+    assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
+    assert(!((dict) && (cdict)));  /* either dict or cdict, not both */
+
+    if (zcs->nbThreads==1) {
+        DEBUGLOG(4, "single thread mode");
+        return ZSTD_initCStream_internal(zcs->cctxPool->cctx[0],
+                                dict, dictSize, cdict,
+                                params, pledgedSrcSize);
+    }
+
+    if (zcs->allJobsCompleted == 0) {   /* previous compression not correctly finished */
         ZSTDMT_waitForAllJobsCompleted(zcs);
         ZSTDMT_releaseAllJobResources(zcs);
         zcs->allJobsCompleted = 1;
     }
+
     zcs->params = params;
-    if (updateDict) {
-        ZSTD_freeCDict(zcs->cdict); zcs->cdict = NULL;
-        if (dict && dictSize) {
-            zcs->cdict = ZSTD_createCDict_advanced(dict, dictSize, 0, params.cParams, cmem);
-            if (zcs->cdict == NULL) return ERROR(memory_allocation);
-    }   }
     zcs->frameContentSize = pledgedSrcSize;
+    if (dict) {
+        DEBUGLOG(4,"cdictLocal: %08X", (U32)(size_t)zcs->cdictLocal);
+        ZSTD_freeCDict(zcs->cdictLocal);
+        zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize,
+                                                    0 /* byRef */, ZSTD_dm_auto,   /* note : a loadPrefix becomes an internal CDict */
+                                                    params.cParams, zcs->cMem);
+        zcs->cdict = zcs->cdictLocal;
+        if (zcs->cdictLocal == NULL) return ERROR(memory_allocation);
+    } else {
+        DEBUGLOG(4,"cdictLocal: %08X", (U32)(size_t)zcs->cdictLocal);
+        ZSTD_freeCDict(zcs->cdictLocal);
+        zcs->cdictLocal = NULL;
+        zcs->cdict = cdict;
+    }
+
     zcs->targetDictSize = (zcs->overlapRLog>=9) ? 0 : (size_t)1 << (zcs->params.cParams.windowLog - zcs->overlapRLog);
     DEBUGLOG(4, "overlapRLog : %u ", zcs->overlapRLog);
-    DEBUGLOG(3, "overlap Size : %u KB", (U32)(zcs->targetDictSize>>10));
+    DEBUGLOG(4, "overlap Size : %u KB", (U32)(zcs->targetDictSize>>10));
     zcs->targetSectionSize = zcs->sectionSize ? zcs->sectionSize : (size_t)1 << (zcs->params.cParams.windowLog + 2);
     zcs->targetSectionSize = MAX(ZSTDMT_SECTION_SIZE_MIN, zcs->targetSectionSize);
     zcs->targetSectionSize = MAX(zcs->targetDictSize, zcs->targetSectionSize);
-    DEBUGLOG(3, "Section Size : %u KB", (U32)(zcs->targetSectionSize>>10));
+    DEBUGLOG(4, "Section Size : %u KB", (U32)(zcs->targetSectionSize>>10));
     zcs->marginSize = zcs->targetSectionSize >> 2;
     zcs->inBuffSize = zcs->targetDictSize + zcs->targetSectionSize + zcs->marginSize;
     zcs->inBuff.buffer = ZSTDMT_getBuffer(zcs->buffPool, zcs->inBuffSize);
@@ -546,24 +663,39 @@ static size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
     return 0;
 }
 
-size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* zcs,
+size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* mtctx,
                                 const void* dict, size_t dictSize,
                                 ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
-    return ZSTDMT_initCStream_internal(zcs, dict, dictSize, 1, params, pledgedSrcSize);
+    DEBUGLOG(5, "ZSTDMT_initCStream_advanced");
+    return ZSTDMT_initCStream_internal(mtctx, dict, dictSize, NULL, params, pledgedSrcSize);
 }
 
+size_t ZSTDMT_initCStream_usingCDict(ZSTDMT_CCtx* mtctx,
+                               const ZSTD_CDict* cdict,
+                                     ZSTD_frameParameters fParams,
+                                     unsigned long long pledgedSrcSize)
+{
+    ZSTD_parameters params = ZSTD_getParamsFromCDict(cdict);
+    if (cdict==NULL) return ERROR(dictionary_wrong);   /* method incompatible with NULL cdict */
+    params.fParams = fParams;
+    return ZSTDMT_initCStream_internal(mtctx, NULL, 0 /*dictSize*/, cdict,
+                                        params, pledgedSrcSize);
+}
+
+
 /* ZSTDMT_resetCStream() :
  * pledgedSrcSize is optional and can be zero == unknown */
 size_t ZSTDMT_resetCStream(ZSTDMT_CCtx* zcs, unsigned long long pledgedSrcSize)
 {
-    if (zcs->nbThreads==1) return ZSTD_resetCStream(zcs->cstream, pledgedSrcSize);
+    if (zcs->nbThreads==1)
+        return ZSTD_resetCStream(zcs->cctxPool->cctx[0], pledgedSrcSize);
     return ZSTDMT_initCStream_internal(zcs, NULL, 0, 0, zcs->params, pledgedSrcSize);
 }
 
 size_t ZSTDMT_initCStream(ZSTDMT_CCtx* zcs, int compressionLevel) {
     ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, 0);
-    return ZSTDMT_initCStream_internal(zcs, NULL, 0, 1, params, 0);
+    return ZSTDMT_initCStream_internal(zcs, NULL, 0, NULL, params, 0);
 }
 
 
@@ -582,13 +714,16 @@ static size_t ZSTDMT_createCompressionJob(ZSTDMT_CCtx* zcs, size_t srcSize, unsi
         return ERROR(memory_allocation);
     }
 
-    DEBUGLOG(4, "preparing job %u to compress %u bytes with %u preload ", zcs->nextJobID, (U32)srcSize, (U32)zcs->dictSize);
+    DEBUGLOG(4, "preparing job %u to compress %u bytes with %u preload ",
+                zcs->nextJobID, (U32)srcSize, (U32)zcs->dictSize);
     zcs->jobs[jobID].src = zcs->inBuff.buffer;
     zcs->jobs[jobID].srcStart = zcs->inBuff.buffer.start;
     zcs->jobs[jobID].srcSize = srcSize;
-    zcs->jobs[jobID].dictSize = zcs->dictSize;   /* note : zcs->inBuff.filled is presumed >= srcSize + dictSize */
+    zcs->jobs[jobID].dictSize = zcs->dictSize;
+    assert(zcs->inBuff.filled >= srcSize + zcs->dictSize);
     zcs->jobs[jobID].params = zcs->params;
-    if (zcs->nextJobID) zcs->jobs[jobID].params.fParams.checksumFlag = 0;  /* do not calculate checksum within sections, just keep it in header for first section */
+    /* do not calculate checksum within sections, but write it in header for first section */
+    if (zcs->nextJobID) zcs->jobs[jobID].params.fParams.checksumFlag = 0;
     zcs->jobs[jobID].cdict = zcs->nextJobID==0 ? zcs->cdict : NULL;
     zcs->jobs[jobID].fullFrameSize = zcs->frameContentSize;
     zcs->jobs[jobID].dstBuff = dstBuffer;
@@ -603,6 +738,7 @@ static size_t ZSTDMT_createCompressionJob(ZSTDMT_CCtx* zcs, size_t srcSize, unsi
     /* get a new buffer for next input */
     if (!endFrame) {
         size_t const newDictSize = MIN(srcSize + zcs->dictSize, zcs->targetDictSize);
+        DEBUGLOG(5, "ZSTDMT_createCompressionJob::endFrame = %u", endFrame);
         zcs->inBuff.buffer = ZSTDMT_getBuffer(zcs->buffPool, zcs->inBuffSize);
         if (zcs->inBuff.buffer.start == NULL) {   /* not enough memory to allocate next input buffer */
             zcs->jobs[jobID].jobCompleted = 1;
@@ -611,22 +747,33 @@ static size_t ZSTDMT_createCompressionJob(ZSTDMT_CCtx* zcs, size_t srcSize, unsi
             ZSTDMT_releaseAllJobResources(zcs);
             return ERROR(memory_allocation);
         }
-        DEBUGLOG(5, "inBuff filled to %u", (U32)zcs->inBuff.filled);
+        DEBUGLOG(5, "inBuff currently filled to %u", (U32)zcs->inBuff.filled);
         zcs->inBuff.filled -= srcSize + zcs->dictSize - newDictSize;
-        DEBUGLOG(5, "new job : filled to %u, with %u dict and %u src", (U32)zcs->inBuff.filled, (U32)newDictSize, (U32)(zcs->inBuff.filled - newDictSize));
-        memmove(zcs->inBuff.buffer.start, (const char*)zcs->jobs[jobID].srcStart + zcs->dictSize + srcSize - newDictSize, zcs->inBuff.filled);
+        DEBUGLOG(5, "new job : inBuff filled to %u, with %u dict and %u src",
+                    (U32)zcs->inBuff.filled, (U32)newDictSize,
+                    (U32)(zcs->inBuff.filled - newDictSize));
+        memmove(zcs->inBuff.buffer.start,
+            (const char*)zcs->jobs[jobID].srcStart + zcs->dictSize + srcSize - newDictSize,
+            zcs->inBuff.filled);
         DEBUGLOG(5, "new inBuff pre-filled");
         zcs->dictSize = newDictSize;
-    } else {
+    } else {   /* if (endFrame==1) */
+        DEBUGLOG(5, "ZSTDMT_createCompressionJob::endFrame = %u", endFrame);
         zcs->inBuff.buffer = g_nullBuffer;
         zcs->inBuff.filled = 0;
         zcs->dictSize = 0;
         zcs->frameEnded = 1;
         if (zcs->nextJobID == 0)
-            zcs->params.fParams.checksumFlag = 0;   /* single chunk : checksum is calculated directly within worker thread */
+            /* single chunk exception : checksum is calculated directly within worker thread */
+            zcs->params.fParams.checksumFlag = 0;
     }
 
-    DEBUGLOG(3, "posting job %u : %u bytes  (end:%u) (note : doneJob = %u=>%u)", zcs->nextJobID, (U32)zcs->jobs[jobID].srcSize, zcs->jobs[jobID].lastChunk, zcs->doneJobID, zcs->doneJobID & zcs->jobIDMask);
+    DEBUGLOG(4, "posting job %u : %u bytes  (end:%u) (note : doneJob = %u=>%u)",
+                zcs->nextJobID,
+                (U32)zcs->jobs[jobID].srcSize,
+                zcs->jobs[jobID].lastChunk,
+                zcs->doneJobID,
+                zcs->doneJobID & zcs->jobIDMask);
     POOL_add(zcs->factory, ZSTDMT_compressChunk, &zcs->jobs[jobID]);   /* this call is blocking when thread worker pool is exhausted */
     zcs->nextJobID++;
     return 0;
@@ -664,7 +811,7 @@ static size_t ZSTDMT_flushNextJob(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, unsi
                 XXH64_update(&zcs->xxhState, (const char*)job.srcStart + job.dictSize, job.srcSize);
                 if (zcs->frameEnded && (zcs->doneJobID+1 == zcs->nextJobID)) {  /* write checksum at end of last section */
                     U32 const checksum = (U32)XXH64_digest(&zcs->xxhState);
-                    DEBUGLOG(4, "writing checksum : %08X \n", checksum);
+                    DEBUGLOG(5, "writing checksum : %08X \n", checksum);
                     MEM_writeLE32((char*)job.dstBuff.start + job.cSize, checksum);
                     job.cSize += 4;
                     zcs->jobs[wJobID].cSize += 4;
@@ -675,7 +822,7 @@ static size_t ZSTDMT_flushNextJob(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, unsi
             zcs->jobs[wJobID].jobScanned = 1;
         }
         {   size_t const toWrite = MIN(job.cSize - job.dstFlushed, output->size - output->pos);
-            DEBUGLOG(4, "Flushing %u bytes from job %u ", (U32)toWrite, zcs->doneJobID);
+            DEBUGLOG(5, "Flushing %u bytes from job %u ", (U32)toWrite, zcs->doneJobID);
             memcpy((char*)output->dst + output->pos, (const char*)job.dstBuff.start + job.dstFlushed, toWrite);
             output->pos += toWrite;
             job.dstFlushed += toWrite;
@@ -696,26 +843,81 @@ static size_t ZSTDMT_flushNextJob(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, unsi
 }   }
 
 
-size_t ZSTDMT_compressStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input)
+/** ZSTDMT_compressStream_generic() :
+ *  internal use only
+ *  assumption : output and input are valid (pos <= size)
+ * @return : minimum amount of data remaining to flush, 0 if none */
+size_t ZSTDMT_compressStream_generic(ZSTDMT_CCtx* mtctx,
+                                     ZSTD_outBuffer* output,
+                                     ZSTD_inBuffer* input,
+                                     ZSTD_EndDirective endOp)
 {
-    size_t const newJobThreshold = zcs->dictSize + zcs->targetSectionSize + zcs->marginSize;
-    if (zcs->frameEnded) return ERROR(stage_wrong);   /* current frame being ended. Only flush is allowed. Restart with init */
-    if (zcs->nbThreads==1) return ZSTD_compressStream(zcs->cstream, output, input);
+    size_t const newJobThreshold = mtctx->dictSize + mtctx->targetSectionSize + mtctx->marginSize;
+    assert(output->pos <= output->size);
+    assert(input->pos  <= input->size);
+    if ((mtctx->frameEnded) && (endOp==ZSTD_e_continue)) {
+        /* current frame being ended. Only flush/end are allowed. Or start new frame with init */
+        return ERROR(stage_wrong);
+    }
+    if (mtctx->nbThreads==1) {
+        return ZSTD_compressStream_generic(mtctx->cctxPool->cctx[0], output, input, endOp);
+    }
+
+    /* single-pass shortcut (note : this is blocking-mode) */
+    if ( (mtctx->nextJobID==0)      /* just started */
+      && (mtctx->inBuff.filled==0)  /* nothing buffered */
+      && (endOp==ZSTD_e_end)        /* end order */
+      && (output->size - output->pos >= ZSTD_compressBound(input->size - input->pos)) ) { /* enough room */
+        size_t const cSize = ZSTDMT_compress_advanced(mtctx,
+                (char*)output->dst + output->pos, output->size - output->pos,
+                (const char*)input->src + input->pos, input->size - input->pos,
+                mtctx->cdict, mtctx->params, mtctx->overlapRLog);
+        if (ZSTD_isError(cSize)) return cSize;
+        input->pos = input->size;
+        output->pos += cSize;
+        ZSTDMT_releaseBuffer(mtctx->buffPool, mtctx->inBuff.buffer);  /* was allocated in initStream */
+        mtctx->allJobsCompleted = 1;
+        mtctx->frameEnded = 1;
+        return 0;
+    }
 
     /* fill input buffer */
-    {   size_t const toLoad = MIN(input->size - input->pos, zcs->inBuffSize - zcs->inBuff.filled);
-        memcpy((char*)zcs->inBuff.buffer.start + zcs->inBuff.filled, input->src, toLoad);
+    if ((input->src) && (mtctx->inBuff.buffer.start)) {   /* support NULL input */
+        size_t const toLoad = MIN(input->size - input->pos, mtctx->inBuffSize - mtctx->inBuff.filled);
+        DEBUGLOG(2, "inBuff:%08X;  inBuffSize=%u;  ToCopy=%u", (U32)(size_t)mtctx->inBuff.buffer.start, (U32)mtctx->inBuffSize, (U32)toLoad);
+        memcpy((char*)mtctx->inBuff.buffer.start + mtctx->inBuff.filled, (const char*)input->src + input->pos, toLoad);
         input->pos += toLoad;
-        zcs->inBuff.filled += toLoad;
+        mtctx->inBuff.filled += toLoad;
     }
 
-    if ( (zcs->inBuff.filled >= newJobThreshold)  /* filled enough : let's compress */
-        && (zcs->nextJobID <= zcs->doneJobID + zcs->jobIDMask) ) {   /* avoid overwriting job round buffer */
-        CHECK_F( ZSTDMT_createCompressionJob(zcs, zcs->targetSectionSize, 0) );
+    if ( (mtctx->inBuff.filled >= newJobThreshold)  /* filled enough : let's compress */
+      && (mtctx->nextJobID <= mtctx->doneJobID + mtctx->jobIDMask) ) {   /* avoid overwriting job round buffer */
+        CHECK_F( ZSTDMT_createCompressionJob(mtctx, mtctx->targetSectionSize, 0 /* endFrame */) );
     }
 
-    /* check for data to flush */
-    CHECK_F( ZSTDMT_flushNextJob(zcs, output, (zcs->inBuff.filled == zcs->inBuffSize)) ); /* block if it wasn't possible to create new job due to saturation */
+    /* check for potential compressed data ready to be flushed */
+    CHECK_F( ZSTDMT_flushNextJob(mtctx, output, (mtctx->inBuff.filled == mtctx->inBuffSize) /* blockToFlush */) ); /* block if it wasn't possible to create new job due to saturation */
+
+    if (input->pos < input->size)  /* input not consumed : do not flush yet */
+        endOp = ZSTD_e_continue;
+
+    switch(endOp)
+    {
+        case ZSTD_e_flush:
+            return ZSTDMT_flushStream(mtctx, output);
+        case ZSTD_e_end:
+            return ZSTDMT_endStream(mtctx, output);
+        case ZSTD_e_continue:
+            return 1;
+        default:
+            return ERROR(GENERIC);   /* invalid endDirective */
+    }
+}
+
+
+size_t ZSTDMT_compressStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input)
+{
+    CHECK_F( ZSTDMT_compressStream_generic(zcs, output, input, ZSTD_e_continue) );
 
     /* recommended next input size : fill current input buffer */
     return zcs->inBuffSize - zcs->inBuff.filled;   /* note : could be zero when input buffer is fully filled and no more availability to create new job */
@@ -726,26 +928,28 @@ static size_t ZSTDMT_flushStream_internal(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* outp
 {
     size_t const srcSize = zcs->inBuff.filled - zcs->dictSize;
 
-    if (srcSize) DEBUGLOG(4, "flushing : %u bytes left to compress", (U32)srcSize);
     if ( ((srcSize > 0) || (endFrame && !zcs->frameEnded))
        && (zcs->nextJobID <= zcs->doneJobID + zcs->jobIDMask) ) {
         CHECK_F( ZSTDMT_createCompressionJob(zcs, srcSize, endFrame) );
     }
 
     /* check if there is any data available to flush */
-    DEBUGLOG(5, "zcs->doneJobID : %u  ; zcs->nextJobID : %u ", zcs->doneJobID, zcs->nextJobID);
-    return ZSTDMT_flushNextJob(zcs, output, 1);
+    return ZSTDMT_flushNextJob(zcs, output, 1 /* blockToFlush */);
 }
 
 
 size_t ZSTDMT_flushStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output)
 {
-    if (zcs->nbThreads==1) return ZSTD_flushStream(zcs->cstream, output);
-    return ZSTDMT_flushStream_internal(zcs, output, 0);
+    DEBUGLOG(5, "ZSTDMT_flushStream");
+    if (zcs->nbThreads==1)
+        return ZSTD_flushStream(zcs->cctxPool->cctx[0], output);
+    return ZSTDMT_flushStream_internal(zcs, output, 0 /* endFrame */);
 }
 
 size_t ZSTDMT_endStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output)
 {
-    if (zcs->nbThreads==1) return ZSTD_endStream(zcs->cstream, output);
-    return ZSTDMT_flushStream_internal(zcs, output, 1);
+    DEBUGLOG(4, "ZSTDMT_endStream");
+    if (zcs->nbThreads==1)
+        return ZSTD_endStream(zcs->cctxPool->cctx[0], output);
+    return ZSTDMT_flushStream_internal(zcs, output, 1 /* endFrame */);
 }
diff --git a/lib/compress/zstdmt_compress.h b/lib/compress/zstdmt_compress.h
index 27f78ee0314a..fad63b6d8610 100644
--- a/lib/compress/zstdmt_compress.h
+++ b/lib/compress/zstdmt_compress.h
@@ -15,25 +15,34 @@
  #endif
 
 
-/* Note : All prototypes defined in this file shall be considered experimental.
- *        There is no guarantee of API continuity (yet) on any of these prototypes */
+/* Note : All prototypes defined in this file are labelled experimental.
+ *        No guarantee of API continuity is provided on any of them.
+ *        In fact, the expectation is that these prototypes will be replaced
+ *        by ZSTD_compress_generic() API in the near future */
 
 /* ===   Dependencies   === */
-#include <stddef.h>   /* size_t */
+#include <stddef.h>                /* size_t */
 #define ZSTD_STATIC_LINKING_ONLY   /* ZSTD_parameters */
-#include "zstd.h"     /* ZSTD_inBuffer, ZSTD_outBuffer, ZSTDLIB_API */
+#include "zstd.h"            /* ZSTD_inBuffer, ZSTD_outBuffer, ZSTDLIB_API */
 
 
-/* ===   Simple one-pass functions   === */
-
+/* ===   Memory management   === */
 typedef struct ZSTDMT_CCtx_s ZSTDMT_CCtx;
 ZSTDLIB_API ZSTDMT_CCtx* ZSTDMT_createCCtx(unsigned nbThreads);
-ZSTDLIB_API size_t ZSTDMT_freeCCtx(ZSTDMT_CCtx* cctx);
+ZSTDLIB_API ZSTDMT_CCtx* ZSTDMT_createCCtx_advanced(unsigned nbThreads,
+                                                    ZSTD_customMem cMem);
+ZSTDLIB_API size_t ZSTDMT_freeCCtx(ZSTDMT_CCtx* mtctx);
+
+ZSTDLIB_API size_t ZSTDMT_sizeof_CCtx(ZSTDMT_CCtx* mtctx);
+
+
+/* ===   Simple buffer-to-butter one-pass function   === */
+
+ZSTDLIB_API size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
+                                       void* dst, size_t dstCapacity,
+                                 const void* src, size_t srcSize,
+                                       int compressionLevel);
 
-ZSTDLIB_API size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* cctx,
-                           void* dst, size_t dstCapacity,
-                     const void* src, size_t srcSize,
-                           int compressionLevel);
 
 
 /* ===   Streaming functions   === */
@@ -53,8 +62,22 @@ ZSTDLIB_API size_t ZSTDMT_endStream(ZSTDMT_CCtx* mtctx, ZSTD_outBuffer* output);
 #  define ZSTDMT_SECTION_SIZE_MIN (1U << 20)   /* 1 MB - Minimum size of each compression job */
 #endif
 
-ZSTDLIB_API size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* mtctx, const void* dict, size_t dictSize,  /**< dict can be released after init, a local copy is preserved within zcs */
-                                          ZSTD_parameters params, unsigned long long pledgedSrcSize);  /**< pledgedSrcSize is optional and can be zero == unknown */
+ZSTDLIB_API size_t ZSTDMT_compress_advanced(ZSTDMT_CCtx* mtctx,
+                                           void* dst, size_t dstCapacity,
+                                     const void* src, size_t srcSize,
+                                     const ZSTD_CDict* cdict,
+                                           ZSTD_parameters const params,
+                                           unsigned overlapRLog);
+
+ZSTDLIB_API size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* mtctx,
+                                        const void* dict, size_t dictSize,   /* dict can be released after init, a local copy is preserved within zcs */
+                                        ZSTD_parameters params,
+                                        unsigned long long pledgedSrcSize);  /* pledgedSrcSize is optional and can be zero == unknown */
+
+ZSTDLIB_API size_t ZSTDMT_initCStream_usingCDict(ZSTDMT_CCtx* mtctx,
+                                        const ZSTD_CDict* cdict,
+                                        ZSTD_frameParameters fparams,
+                                        unsigned long long pledgedSrcSize);  /* note : zero means empty */
 
 /* ZSDTMT_parameter :
  * List of parameters that can be set using ZSTDMT_setMTCtxParameter() */
@@ -71,6 +94,19 @@ typedef enum {
 ZSTDLIB_API size_t ZSTDMT_setMTCtxParameter(ZSTDMT_CCtx* mtctx, ZSDTMT_parameter parameter, unsigned value);
 
 
+/*! ZSTDMT_compressStream_generic() :
+ *  Combines ZSTDMT_compressStream() with ZSTDMT_flushStream() or ZSTDMT_endStream()
+ *  depending on flush directive.
+ * @return : minimum amount of data still to be flushed
+ *           0 if fully flushed
+ *           or an error code */
+ZSTDLIB_API size_t ZSTDMT_compressStream_generic(ZSTDMT_CCtx* mtctx,
+                                                ZSTD_outBuffer* output,
+                                                ZSTD_inBuffer* input,
+                                                ZSTD_EndDirective endOp);
+
+
+
 #if defined (__cplusplus)
 }
 #endif
diff --git a/lib/decompress/huf_decompress.c b/lib/decompress/huf_decompress.c
index ea35c3620176..2a1b70ea5ef2 100644
--- a/lib/decompress/huf_decompress.c
+++ b/lib/decompress/huf_decompress.c
@@ -67,6 +67,12 @@
 #define HUF_STATIC_ASSERT(c) { enum { HUF_static_assert = 1/(int)(!!(c)) }; }   /* use only *after* variable declarations */
 
 
+/* **************************************************************
+*  Byte alignment for workSpace management
+****************************************************************/
+#define HUF_ALIGN(x, a) HUF_ALIGN_MASK((x), (a) - 1)
+#define HUF_ALIGN_MASK(x, mask) (((x) + (mask)) & ~(mask))
+
 /*-***************************/
 /*  generic DTableDesc       */
 /*-***************************/
@@ -87,16 +93,28 @@ static DTableDesc HUF_getDTableDesc(const HUF_DTable* table)
 
 typedef struct { BYTE byte; BYTE nbBits; } HUF_DEltX2;   /* single-symbol decoding */
 
-size_t HUF_readDTableX2 (HUF_DTable* DTable, const void* src, size_t srcSize)
+size_t HUF_readDTableX2_wksp(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize)
 {
-    BYTE huffWeight[HUF_SYMBOLVALUE_MAX + 1];
-    U32 rankVal[HUF_TABLELOG_ABSOLUTEMAX + 1];   /* large enough for values from 0 to 16 */
     U32 tableLog = 0;
     U32 nbSymbols = 0;
     size_t iSize;
     void* const dtPtr = DTable + 1;
     HUF_DEltX2* const dt = (HUF_DEltX2*)dtPtr;
 
+    U32* rankVal;
+    BYTE* huffWeight;
+    size_t spaceUsed32 = 0;
+
+    rankVal = (U32 *)workSpace + spaceUsed32;
+    spaceUsed32 += HUF_TABLELOG_ABSOLUTEMAX + 1;
+    huffWeight = (BYTE *)((U32 *)workSpace + spaceUsed32);
+    spaceUsed32 += HUF_ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2;
+
+    if ((spaceUsed32 << 2) > wkspSize)
+        return ERROR(tableLog_tooLarge);
+    workSpace = (U32 *)workSpace + spaceUsed32;
+    wkspSize -= (spaceUsed32 << 2);
+
     HUF_STATIC_ASSERT(sizeof(DTableDesc) == sizeof(HUF_DTable));
     /* memset(huffWeight, 0, sizeof(huffWeight)); */   /* is not necessary, even though some analyzer complain ... */
 
@@ -135,6 +153,13 @@ size_t HUF_readDTableX2 (HUF_DTable* DTable, const void* src, size_t srcSize)
     return iSize;
 }
 
+size_t HUF_readDTableX2(HUF_DTable* DTable, const void* src, size_t srcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_readDTableX2_wksp(DTable, src, srcSize,
+                                 workSpace, sizeof(workSpace));
+}
+
 
 static BYTE HUF_decodeSymbolX2(BIT_DStream_t* Dstream, const HUF_DEltX2* dt, const U32 dtLog)
 {
@@ -212,11 +237,13 @@ size_t HUF_decompress1X2_usingDTable(
     return HUF_decompress1X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
 }
 
-size_t HUF_decompress1X2_DCtx (HUF_DTable* DCtx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable* DCtx, void* dst, size_t dstSize,
+                                   const void* cSrc, size_t cSrcSize,
+                                   void* workSpace, size_t wkspSize)
 {
     const BYTE* ip = (const BYTE*) cSrc;
 
-    size_t const hSize = HUF_readDTableX2 (DCtx, cSrc, cSrcSize);
+    size_t const hSize = HUF_readDTableX2_wksp(DCtx, cSrc, cSrcSize, workSpace, wkspSize);
     if (HUF_isError(hSize)) return hSize;
     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
     ip += hSize; cSrcSize -= hSize;
@@ -224,6 +251,15 @@ size_t HUF_decompress1X2_DCtx (HUF_DTable* DCtx, void* dst, size_t dstSize, cons
     return HUF_decompress1X2_usingDTable_internal (dst, dstSize, ip, cSrcSize, DCtx);
 }
 
+
+size_t HUF_decompress1X2_DCtx(HUF_DTable* DCtx, void* dst, size_t dstSize,
+                              const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress1X2_DCtx_wksp(DCtx, dst, dstSize, cSrc, cSrcSize,
+                                       workSpace, sizeof(workSpace));
+}
+
 size_t HUF_decompress1X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
 {
     HUF_CREATE_STATIC_DTABLEX2(DTable, HUF_TABLELOG_MAX);
@@ -335,11 +371,14 @@ size_t HUF_decompress4X2_usingDTable(
 }
 
 
-size_t HUF_decompress4X2_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
+                                   const void* cSrc, size_t cSrcSize,
+                                   void* workSpace, size_t wkspSize)
 {
     const BYTE* ip = (const BYTE*) cSrc;
 
-    size_t const hSize = HUF_readDTableX2 (dctx, cSrc, cSrcSize);
+    size_t const hSize = HUF_readDTableX2_wksp (dctx, cSrc, cSrcSize,
+                                                workSpace, wkspSize);
     if (HUF_isError(hSize)) return hSize;
     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
     ip += hSize; cSrcSize -= hSize;
@@ -347,6 +386,13 @@ size_t HUF_decompress4X2_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, cons
     return HUF_decompress4X2_usingDTable_internal (dst, dstSize, ip, cSrcSize, dctx);
 }
 
+
+size_t HUF_decompress4X2_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize,
+                                       workSpace, sizeof(workSpace));
+}
 size_t HUF_decompress4X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
 {
     HUF_CREATE_STATIC_DTABLEX2(DTable, HUF_TABLELOG_MAX);
@@ -403,7 +449,8 @@ static void HUF_fillDTableX4Level2(HUF_DEltX4* DTable, U32 sizeLog, const U32 co
     }   }
 }
 
-typedef U32 rankVal_t[HUF_TABLELOG_MAX][HUF_TABLELOG_MAX + 1];
+typedef U32 rankValCol_t[HUF_TABLELOG_MAX + 1];
+typedef rankValCol_t rankVal_t[HUF_TABLELOG_MAX];
 
 static void HUF_fillDTableX4(HUF_DEltX4* DTable, const U32 targetLog,
                            const sortedSymbol_t* sortedList, const U32 sortedListSize,
@@ -447,20 +494,43 @@ static void HUF_fillDTableX4(HUF_DEltX4* DTable, const U32 targetLog,
     }
 }
 
-size_t HUF_readDTableX4 (HUF_DTable* DTable, const void* src, size_t srcSize)
+size_t HUF_readDTableX4_wksp(HUF_DTable* DTable, const void* src,
+                             size_t srcSize, void* workSpace,
+                             size_t wkspSize)
 {
-    BYTE weightList[HUF_SYMBOLVALUE_MAX + 1];
-    sortedSymbol_t sortedSymbol[HUF_SYMBOLVALUE_MAX + 1];
-    U32 rankStats[HUF_TABLELOG_MAX + 1] = { 0 };
-    U32 rankStart0[HUF_TABLELOG_MAX + 2] = { 0 };
-    U32* const rankStart = rankStart0+1;
-    rankVal_t rankVal;
     U32 tableLog, maxW, sizeOfSort, nbSymbols;
     DTableDesc dtd = HUF_getDTableDesc(DTable);
     U32 const maxTableLog = dtd.maxTableLog;
     size_t iSize;
     void* dtPtr = DTable+1;   /* force compiler to avoid strict-aliasing */
     HUF_DEltX4* const dt = (HUF_DEltX4*)dtPtr;
+    U32 *rankStart;
+
+    rankValCol_t* rankVal;
+    U32* rankStats;
+    U32* rankStart0;
+    sortedSymbol_t* sortedSymbol;
+    BYTE* weightList;
+    size_t spaceUsed32 = 0;
+
+    rankVal = (rankValCol_t *)((U32 *)workSpace + spaceUsed32);
+    spaceUsed32 += (sizeof(rankValCol_t) * HUF_TABLELOG_MAX) >> 2;
+    rankStats = (U32 *)workSpace + spaceUsed32;
+    spaceUsed32 += HUF_TABLELOG_MAX + 1;
+    rankStart0 = (U32 *)workSpace + spaceUsed32;
+    spaceUsed32 += HUF_TABLELOG_MAX + 2;
+    sortedSymbol = (sortedSymbol_t *)workSpace + (spaceUsed32 * sizeof(U32)) / sizeof(sortedSymbol_t);
+    spaceUsed32 += HUF_ALIGN(sizeof(sortedSymbol_t) * (HUF_SYMBOLVALUE_MAX + 1), sizeof(U32)) >> 2;
+    weightList = (BYTE *)((U32 *)workSpace + spaceUsed32);
+    spaceUsed32 += HUF_ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2;
+
+    if ((spaceUsed32 << 2) > wkspSize)
+        return ERROR(tableLog_tooLarge);
+    workSpace = (U32 *)workSpace + spaceUsed32;
+    wkspSize -= (spaceUsed32 << 2);
+
+    rankStart = rankStart0 + 1;
+    memset(rankStats, 0, sizeof(U32) * (2 * HUF_TABLELOG_MAX + 2 + 1));
 
     HUF_STATIC_ASSERT(sizeof(HUF_DEltX4) == sizeof(HUF_DTable));   /* if compiler fails here, assertion is wrong */
     if (maxTableLog > HUF_TABLELOG_MAX) return ERROR(tableLog_tooLarge);
@@ -527,6 +597,12 @@ size_t HUF_readDTableX4 (HUF_DTable* DTable, const void* src, size_t srcSize)
     return iSize;
 }
 
+size_t HUF_readDTableX4(HUF_DTable* DTable, const void* src, size_t srcSize)
+{
+  U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+  return HUF_readDTableX4_wksp(DTable, src, srcSize,
+                               workSpace, sizeof(workSpace));
+}
 
 static U32 HUF_decodeSymbolX4(void* op, BIT_DStream_t* DStream, const HUF_DEltX4* dt, const U32 dtLog)
 {
@@ -545,7 +621,8 @@ static U32 HUF_decodeLastSymbolX4(void* op, BIT_DStream_t* DStream, const HUF_DE
         if (DStream->bitsConsumed < (sizeof(DStream->bitContainer)*8)) {
             BIT_skipBits(DStream, dt[val].nbBits);
             if (DStream->bitsConsumed > (sizeof(DStream->bitContainer)*8))
-                DStream->bitsConsumed = (sizeof(DStream->bitContainer)*8);   /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */
+                /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */
+                DStream->bitsConsumed = (sizeof(DStream->bitContainer)*8);
     }   }
     return 1;
 }
@@ -626,11 +703,14 @@ size_t HUF_decompress1X4_usingDTable(
     return HUF_decompress1X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
 }
 
-size_t HUF_decompress1X4_DCtx (HUF_DTable* DCtx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable* DCtx, void* dst, size_t dstSize,
+                                   const void* cSrc, size_t cSrcSize,
+                                   void* workSpace, size_t wkspSize)
 {
     const BYTE* ip = (const BYTE*) cSrc;
 
-    size_t const hSize = HUF_readDTableX4 (DCtx, cSrc, cSrcSize);
+    size_t const hSize = HUF_readDTableX4_wksp(DCtx, cSrc, cSrcSize,
+                                               workSpace, wkspSize);
     if (HUF_isError(hSize)) return hSize;
     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
     ip += hSize; cSrcSize -= hSize;
@@ -638,6 +718,15 @@ size_t HUF_decompress1X4_DCtx (HUF_DTable* DCtx, void* dst, size_t dstSize, cons
     return HUF_decompress1X4_usingDTable_internal (dst, dstSize, ip, cSrcSize, DCtx);
 }
 
+
+size_t HUF_decompress1X4_DCtx(HUF_DTable* DCtx, void* dst, size_t dstSize,
+                              const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress1X4_DCtx_wksp(DCtx, dst, dstSize, cSrc, cSrcSize,
+                                       workSpace, sizeof(workSpace));
+}
+
 size_t HUF_decompress1X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
 {
     HUF_CREATE_STATIC_DTABLEX4(DTable, HUF_TABLELOG_MAX);
@@ -748,11 +837,14 @@ size_t HUF_decompress4X4_usingDTable(
 }
 
 
-size_t HUF_decompress4X4_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
+                                   const void* cSrc, size_t cSrcSize,
+                                   void* workSpace, size_t wkspSize)
 {
     const BYTE* ip = (const BYTE*) cSrc;
 
-    size_t hSize = HUF_readDTableX4 (dctx, cSrc, cSrcSize);
+    size_t hSize = HUF_readDTableX4_wksp(dctx, cSrc, cSrcSize,
+                                         workSpace, wkspSize);
     if (HUF_isError(hSize)) return hSize;
     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
     ip += hSize; cSrcSize -= hSize;
@@ -760,6 +852,15 @@ size_t HUF_decompress4X4_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, cons
     return HUF_decompress4X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx);
 }
 
+
+size_t HUF_decompress4X4_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize,
+                              const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize,
+                                       workSpace, sizeof(workSpace));
+}
+
 size_t HUF_decompress4X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
 {
     HUF_CREATE_STATIC_DTABLEX4(DTable, HUF_TABLELOG_MAX);
@@ -861,19 +962,32 @@ size_t HUF_decompress4X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const
     }
 }
 
-size_t HUF_decompress4X_hufOnly (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress4X_hufOnly(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress4X_hufOnly_wksp(dctx, dst, dstSize, cSrc, cSrcSize,
+                                         workSpace, sizeof(workSpace));
+}
+
+
+size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable* dctx, void* dst,
+                                     size_t dstSize, const void* cSrc,
+                                     size_t cSrcSize, void* workSpace,
+                                     size_t wkspSize)
 {
     /* validation checks */
     if (dstSize == 0) return ERROR(dstSize_tooSmall);
     if ((cSrcSize >= dstSize) || (cSrcSize <= 1)) return ERROR(corruption_detected);   /* invalid */
 
     {   U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
-        return algoNb ? HUF_decompress4X4_DCtx(dctx, dst, dstSize, cSrc, cSrcSize) :
-                        HUF_decompress4X2_DCtx(dctx, dst, dstSize, cSrc, cSrcSize) ;
+        return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize):
+                        HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize);
     }
 }
 
-size_t HUF_decompress1X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress1X_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
+                                  const void* cSrc, size_t cSrcSize,
+                                  void* workSpace, size_t wkspSize)
 {
     /* validation checks */
     if (dstSize == 0) return ERROR(dstSize_tooSmall);
@@ -882,7 +996,17 @@ size_t HUF_decompress1X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const
     if (cSrcSize == 1) { memset(dst, *(const BYTE*)cSrc, dstSize); return dstSize; }   /* RLE */
 
     {   U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
-        return algoNb ? HUF_decompress1X4_DCtx(dctx, dst, dstSize, cSrc, cSrcSize) :
-                        HUF_decompress1X2_DCtx(dctx, dst, dstSize, cSrc, cSrcSize) ;
+        return algoNb ? HUF_decompress1X4_DCtx_wksp(dctx, dst, dstSize, cSrc,
+                                cSrcSize, workSpace, wkspSize):
+                        HUF_decompress1X2_DCtx_wksp(dctx, dst, dstSize, cSrc,
+                                cSrcSize, workSpace, wkspSize);
     }
 }
+
+size_t HUF_decompress1X_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize,
+                             const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress1X_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize,
+                                      workSpace, sizeof(workSpace));
+}
diff --git a/lib/decompress/zstd_decompress.c b/lib/decompress/zstd_decompress.c
index 910f9ab783c3..003d703a5eb3 100644
--- a/lib/decompress/zstd_decompress.c
+++ b/lib/decompress/zstd_decompress.c
@@ -53,8 +53,7 @@
 #  include "zstd_legacy.h"
 #endif
 
-
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && !defined(_M_IA64)  /* _mm_prefetch() is not defined for ia64 */
 #  include <mmintrin.h>   /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */
 #  define ZSTD_PREFETCH(ptr)   _mm_prefetch((const char*)ptr, _MM_HINT_T0)
 #elif defined(__GNUC__)
@@ -63,8 +62,9 @@
 #  define ZSTD_PREFETCH(ptr)   /* disabled */
 #endif
 
+
 /*-*************************************
-*  Macros
+*  Errors
 ***************************************/
 #define ZSTD_isError ERR_isError   /* for inlining */
 #define FSE_isError  ERR_isError
@@ -85,11 +85,15 @@ typedef enum { ZSTDds_getFrameHeaderSize, ZSTDds_decodeFrameHeader,
                ZSTDds_decompressLastBlock, ZSTDds_checkChecksum,
                ZSTDds_decodeSkippableHeader, ZSTDds_skipFrame } ZSTD_dStage;
 
+typedef enum { zdss_init=0, zdss_loadHeader,
+               zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage;
+
 typedef struct {
     FSE_DTable LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)];
     FSE_DTable OFTable[FSE_DTABLE_SIZE_U32(OffFSELog)];
     FSE_DTable MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)];
     HUF_DTable hufTable[HUF_DTABLE_SIZE(HufLog)];  /* can accommodate HUF_decompress4X */
+    U32 workspace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
     U32 rep[ZSTD_REP_NUM];
 } ZSTD_entropyTables_t;
 
@@ -105,7 +109,7 @@ struct ZSTD_DCtx_s
     const void* vBase;            /* virtual start of previous segment if it was just before current one */
     const void* dictEnd;          /* end of previous segment */
     size_t expected;
-    ZSTD_frameParams fParams;
+    ZSTD_frameHeader fParams;
     blockType_e bType;   /* used in ZSTD_decompressContinue(), to transfer blockType between header decoding and block decoding stages */
     ZSTD_dStage stage;
     U32 litEntropy;
@@ -117,11 +121,39 @@ struct ZSTD_DCtx_s
     ZSTD_customMem customMem;
     size_t litSize;
     size_t rleSize;
-    BYTE litBuffer[ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH];
+    size_t staticSize;
+
+    /* streaming */
+    ZSTD_DDict* ddictLocal;
+    const ZSTD_DDict* ddict;
+    ZSTD_dStreamStage streamStage;
+    char*  inBuff;
+    size_t inBuffSize;
+    size_t inPos;
+    size_t maxWindowSize;
+    char*  outBuff;
+    size_t outBuffSize;
+    size_t outStart;
+    size_t outEnd;
+    size_t blockSize;
+    size_t lhSize;
+    void* legacyContext;
+    U32 previousLegacyVersion;
+    U32 legacyVersion;
+    U32 hostageByte;
+
+    /* workspace */
+    BYTE litBuffer[ZSTD_BLOCKSIZE_MAX + WILDCOPY_OVERLENGTH];
     BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX];
 };  /* typedef'd to ZSTD_DCtx within "zstd.h" */
 
-size_t ZSTD_sizeof_DCtx (const ZSTD_DCtx* dctx) { return (dctx==NULL) ? 0 : sizeof(ZSTD_DCtx); }
+size_t ZSTD_sizeof_DCtx (const ZSTD_DCtx* dctx)
+{
+    if (dctx==NULL) return 0;   /* support sizeof NULL */
+    return sizeof(*dctx)
+           + ZSTD_sizeof_DDict(dctx->ddictLocal)
+           + dctx->inBuffSize + dctx->outBuffSize;
+}
 
 size_t ZSTD_estimateDCtxSize(void) { return sizeof(ZSTD_DCtx); }
 
@@ -145,40 +177,76 @@ size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx)
     return 0;
 }
 
+static void ZSTD_initDCtx_internal(ZSTD_DCtx* dctx)
+{
+    ZSTD_decompressBegin(dctx);   /* cannot fail */
+    dctx->staticSize = 0;
+    dctx->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT;
+    dctx->ddict   = NULL;
+    dctx->ddictLocal = NULL;
+    dctx->inBuff  = NULL;
+    dctx->inBuffSize = 0;
+    dctx->outBuffSize= 0;
+    dctx->streamStage = zdss_init;
+}
+
 ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem)
 {
-    ZSTD_DCtx* dctx;
+    if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
 
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    {   ZSTD_DCtx* const dctx = (ZSTD_DCtx*)ZSTD_malloc(sizeof(*dctx), customMem);
+        if (!dctx) return NULL;
+        dctx->customMem = customMem;
+        dctx->legacyContext = NULL;
+        dctx->previousLegacyVersion = 0;
+        ZSTD_initDCtx_internal(dctx);
+        return dctx;
+    }
+}
 
-    dctx = (ZSTD_DCtx*)ZSTD_malloc(sizeof(ZSTD_DCtx), customMem);
-    if (!dctx) return NULL;
-    memcpy(&dctx->customMem, &customMem, sizeof(customMem));
-    ZSTD_decompressBegin(dctx);
+ZSTD_DCtx* ZSTD_initStaticDCtx(void *workspace, size_t workspaceSize)
+{
+    ZSTD_DCtx* dctx = (ZSTD_DCtx*) workspace;
+
+    if ((size_t)workspace & 7) return NULL;  /* 8-aligned */
+    if (workspaceSize < sizeof(ZSTD_DCtx)) return NULL;  /* minimum size */
+
+    ZSTD_initDCtx_internal(dctx);
+    dctx->staticSize = workspaceSize;
+    dctx->inBuff = (char*)(dctx+1);
     return dctx;
 }
 
 ZSTD_DCtx* ZSTD_createDCtx(void)
 {
-    return ZSTD_createDCtx_advanced(defaultCustomMem);
+    return ZSTD_createDCtx_advanced(ZSTD_defaultCMem);
 }
 
 size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx)
 {
     if (dctx==NULL) return 0;   /* support free on NULL */
-    ZSTD_free(dctx, dctx->customMem);
-    return 0;   /* reserved as a potential error code in the future */
+    if (dctx->staticSize) return ERROR(memory_allocation);   /* not compatible with static DCtx */
+    {   ZSTD_customMem const cMem = dctx->customMem;
+        ZSTD_freeDDict(dctx->ddictLocal);
+        dctx->ddictLocal = NULL;
+        ZSTD_free(dctx->inBuff, cMem);
+        dctx->inBuff = NULL;
+#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1)
+        if (dctx->legacyContext)
+            ZSTD_freeLegacyStreamContext(dctx->legacyContext, dctx->previousLegacyVersion);
+#endif
+        ZSTD_free(dctx, cMem);
+        return 0;
+    }
 }
 
+/* no longer useful */
 void ZSTD_copyDCtx(ZSTD_DCtx* dstDCtx, const ZSTD_DCtx* srcDCtx)
 {
-    size_t const workSpaceSize = (ZSTD_BLOCKSIZE_ABSOLUTEMAX+WILDCOPY_OVERLENGTH) + ZSTD_frameHeaderSize_max;
-    memcpy(dstDCtx, srcDCtx, sizeof(ZSTD_DCtx) - workSpaceSize);  /* no need to copy workspace */
+    size_t const toCopy = (size_t)((char*)(&dstDCtx->inBuff) - (char*)dstDCtx);
+    memcpy(dstDCtx, srcDCtx, toCopy);  /* no need to copy workspace */
 }
 
-static void ZSTD_refDDict(ZSTD_DCtx* dstDCtx, const ZSTD_DDict* ddict);
-
 
 /*-*************************************************************
 *   Decompression section
@@ -206,7 +274,7 @@ unsigned ZSTD_isFrame(const void* buffer, size_t size)
 /** ZSTD_frameHeaderSize() :
 *   srcSize must be >= ZSTD_frameHeaderSize_prefix.
 *   @return : size of the Frame Header */
-static size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize)
+size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize)
 {
     if (srcSize < ZSTD_frameHeaderSize_prefix) return ERROR(srcSize_wrong);
     {   BYTE const fhd = ((const BYTE*)src)[4];
@@ -219,22 +287,24 @@ static size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize)
 }
 
 
-/** ZSTD_getFrameParams() :
+/** ZSTD_getFrameHeader() :
 *   decode Frame Header, or require larger `srcSize`.
-*   @return : 0, `fparamsPtr` is correctly filled,
+*   @return : 0, `zfhPtr` is correctly filled,
 *            >0, `srcSize` is too small, result is expected `srcSize`,
 *             or an error code, which can be tested using ZSTD_isError() */
-size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t srcSize)
+size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize)
 {
     const BYTE* ip = (const BYTE*)src;
-
     if (srcSize < ZSTD_frameHeaderSize_prefix) return ZSTD_frameHeaderSize_prefix;
+
     if (MEM_readLE32(src) != ZSTD_MAGICNUMBER) {
         if ((MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
-            if (srcSize < ZSTD_skippableHeaderSize) return ZSTD_skippableHeaderSize; /* magic number + skippable frame length */
-            memset(fparamsPtr, 0, sizeof(*fparamsPtr));
-            fparamsPtr->frameContentSize = MEM_readLE32((const char *)src + 4);
-            fparamsPtr->windowSize = 0; /* windowSize==0 means a frame is skippable */
+            /* skippable frame */
+            if (srcSize < ZSTD_skippableHeaderSize)
+                return ZSTD_skippableHeaderSize; /* magic number + frame length */
+            memset(zfhPtr, 0, sizeof(*zfhPtr));
+            zfhPtr->frameContentSize = MEM_readLE32((const char *)src + 4);
+            zfhPtr->windowSize = 0; /* windowSize==0 means a frame is skippable */
             return 0;
         }
         return ERROR(prefix_unknown);
@@ -254,11 +324,13 @@ size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t
         U32 windowSize = 0;
         U32 dictID = 0;
         U64 frameContentSize = 0;
-        if ((fhdByte & 0x08) != 0) return ERROR(frameParameter_unsupported);   /* reserved bits, which must be zero */
+        if ((fhdByte & 0x08) != 0)
+            return ERROR(frameParameter_unsupported);   /* reserved bits, must be zero */
         if (!singleSegment) {
             BYTE const wlByte = ip[pos++];
             U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN;
-            if (windowLog > ZSTD_WINDOWLOG_MAX) return ERROR(frameParameter_windowTooLarge);  /* avoids issue with 1 << windowLog */
+            if (windowLog > ZSTD_WINDOWLOG_MAX)
+                return ERROR(frameParameter_windowTooLarge);
             windowSize = (1U << windowLog);
             windowSize += (windowSize >> 3) * (wlByte&7);
         }
@@ -281,10 +353,10 @@ size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t
         }
         if (!windowSize) windowSize = (U32)frameContentSize;
         if (windowSize > windowSizeMax) return ERROR(frameParameter_windowTooLarge);
-        fparamsPtr->frameContentSize = frameContentSize;
-        fparamsPtr->windowSize = windowSize;
-        fparamsPtr->dictID = dictID;
-        fparamsPtr->checksumFlag = checksumFlag;
+        zfhPtr->frameContentSize = frameContentSize;
+        zfhPtr->windowSize = windowSize;
+        zfhPtr->dictID = dictID;
+        zfhPtr->checksumFlag = checksumFlag;
     }
     return 0;
 }
@@ -302,9 +374,8 @@ unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize)
         return ret == 0 ? ZSTD_CONTENTSIZE_UNKNOWN : ret;
     }
 #endif
-    {
-        ZSTD_frameParams fParams;
-        if (ZSTD_getFrameParams(&fParams, src, srcSize) != 0) return ZSTD_CONTENTSIZE_ERROR;
+    {   ZSTD_frameHeader fParams;
+        if (ZSTD_getFrameHeader(&fParams, src, srcSize) != 0) return ZSTD_CONTENTSIZE_ERROR;
         if (fParams.windowSize == 0) {
             /* Either skippable or empty frame, size == 0 either way */
             return 0;
@@ -323,51 +394,48 @@ unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize)
  *  @return : decompressed size of the frames contained */
 unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize)
 {
-    {
-        unsigned long long totalDstSize = 0;
-        while (srcSize >= ZSTD_frameHeaderSize_prefix) {
-            const U32 magicNumber = MEM_readLE32(src);
+    unsigned long long totalDstSize = 0;
 
-            if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
-                size_t skippableSize;
-                if (srcSize < ZSTD_skippableHeaderSize)
-                    return ERROR(srcSize_wrong);
-                skippableSize = MEM_readLE32((const BYTE *)src + 4) +
-                                ZSTD_skippableHeaderSize;
-                if (srcSize < skippableSize) {
-                    return ZSTD_CONTENTSIZE_ERROR;
-                }
-
-                src = (const BYTE *)src + skippableSize;
-                srcSize -= skippableSize;
-                continue;
+    while (srcSize >= ZSTD_frameHeaderSize_prefix) {
+        const U32 magicNumber = MEM_readLE32(src);
+
+        if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
+            size_t skippableSize;
+            if (srcSize < ZSTD_skippableHeaderSize)
+                return ERROR(srcSize_wrong);
+            skippableSize = MEM_readLE32((const BYTE *)src + 4) +
+                            ZSTD_skippableHeaderSize;
+            if (srcSize < skippableSize) {
+                return ZSTD_CONTENTSIZE_ERROR;
             }
 
-            {
-                unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize);
-                if (ret >= ZSTD_CONTENTSIZE_ERROR) return ret;
+            src = (const BYTE *)src + skippableSize;
+            srcSize -= skippableSize;
+            continue;
+        }
 
-                /* check for overflow */
-                if (totalDstSize + ret < totalDstSize) return ZSTD_CONTENTSIZE_ERROR;
-                totalDstSize += ret;
-            }
-            {
-                size_t const frameSrcSize = ZSTD_findFrameCompressedSize(src, srcSize);
-                if (ZSTD_isError(frameSrcSize)) {
-                    return ZSTD_CONTENTSIZE_ERROR;
-                }
+        {   unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize);
+            if (ret >= ZSTD_CONTENTSIZE_ERROR) return ret;
 
-                src = (const BYTE *)src + frameSrcSize;
-                srcSize -= frameSrcSize;
-            }
+            /* check for overflow */
+            if (totalDstSize + ret < totalDstSize) return ZSTD_CONTENTSIZE_ERROR;
+            totalDstSize += ret;
         }
+        {   size_t const frameSrcSize = ZSTD_findFrameCompressedSize(src, srcSize);
+            if (ZSTD_isError(frameSrcSize)) {
+                return ZSTD_CONTENTSIZE_ERROR;
+            }
 
-        if (srcSize) {
-            return ZSTD_CONTENTSIZE_ERROR;
+            src = (const BYTE *)src + frameSrcSize;
+            srcSize -= frameSrcSize;
         }
+    }
 
-        return totalDstSize;
+    if (srcSize) {
+        return ZSTD_CONTENTSIZE_ERROR;
     }
+
+    return totalDstSize;
 }
 
 /** ZSTD_getDecompressedSize() :
@@ -389,7 +457,7 @@ unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize)
 *   @return : 0 if success, or an error code, which can be tested using ZSTD_isError() */
 static size_t ZSTD_decodeFrameHeader(ZSTD_DCtx* dctx, const void* src, size_t headerSize)
 {
-    size_t const result = ZSTD_getFrameParams(&(dctx->fParams), src, headerSize);
+    size_t const result = ZSTD_getFrameHeader(&(dctx->fParams), src, headerSize);
     if (ZSTD_isError(result)) return result;  /* invalid header */
     if (result>0) return ERROR(srcSize_wrong);   /* headerSize too small */
     if (dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID)) return ERROR(dictionary_wrong);
@@ -485,7 +553,7 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
                     litCSize = (lhc >> 22) + (istart[4] << 10);
                     break;
                 }
-                if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) return ERROR(corruption_detected);
+                if (litSize > ZSTD_BLOCKSIZE_MAX) return ERROR(corruption_detected);
                 if (litCSize + lhSize > srcSize) return ERROR(corruption_detected);
 
                 if (HUF_isError((litEncType==set_repeat) ?
@@ -493,8 +561,10 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
                                         HUF_decompress1X_usingDTable(dctx->litBuffer, litSize, istart+lhSize, litCSize, dctx->HUFptr) :
                                         HUF_decompress4X_usingDTable(dctx->litBuffer, litSize, istart+lhSize, litCSize, dctx->HUFptr) ) :
                                     ( singleStream ?
-                                        HUF_decompress1X2_DCtx(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize) :
-                                        HUF_decompress4X_hufOnly (dctx->entropy.hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize)) ))
+                                        HUF_decompress1X2_DCtx_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize,
+                                                                    dctx->entropy.workspace, sizeof(dctx->entropy.workspace)) :
+                                        HUF_decompress4X_hufOnly_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize,
+                                                                      dctx->entropy.workspace, sizeof(dctx->entropy.workspace)))))
                     return ERROR(corruption_detected);
 
                 dctx->litPtr = dctx->litBuffer;
@@ -557,7 +627,7 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
                     if (srcSize<4) return ERROR(corruption_detected);   /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4 */
                     break;
                 }
-                if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) return ERROR(corruption_detected);
+                if (litSize > ZSTD_BLOCKSIZE_MAX) return ERROR(corruption_detected);
                 memset(dctx->litBuffer, istart[lhSize], litSize + WILDCOPY_OVERLENGTH);
                 dctx->litPtr = dctx->litBuffer;
                 dctx->litSize = litSize;
@@ -684,6 +754,7 @@ size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr,
     const BYTE* const istart = (const BYTE* const)src;
     const BYTE* const iend = istart + srcSize;
     const BYTE* ip = istart;
+    DEBUGLOG(5, "ZSTD_decodeSeqHeaders");
 
     /* check */
     if (srcSize < MIN_SEQUENCES_SIZE) return ERROR(srcSize_wrong);
@@ -864,12 +935,18 @@ static seq_t ZSTD_decodeSequence(seqState_t* seqState)
         seq.offset = offset;
     }
 
-    seq.matchLength = ML_base[mlCode] + ((mlCode>31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0);  /* <=  16 bits */
+    seq.matchLength = ML_base[mlCode]
+                    + ((mlCode>31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0);  /* <=  16 bits */
     if (MEM_32bits() && (mlBits+llBits>24)) BIT_reloadDStream(&seqState->DStream);
 
-    seq.litLength = LL_base[llCode] + ((llCode>15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0);    /* <=  16 bits */
-    if (MEM_32bits() ||
-       (totalBits > 64 - 7 - (LLFSELog+MLFSELog+OffFSELog)) ) BIT_reloadDStream(&seqState->DStream);
+    seq.litLength = LL_base[llCode]
+                  + ((llCode>15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0);    /* <=  16 bits */
+    if (  MEM_32bits()
+      || (totalBits > 64 - 7 - (LLFSELog+MLFSELog+OffFSELog)) )
+       BIT_reloadDStream(&seqState->DStream);
+
+    DEBUGLOG(6, "seq: litL=%u, matchL=%u, offset=%u",
+                (U32)seq.litLength, (U32)seq.matchLength, (U32)seq.offset);
 
     /* ANS state update */
     FSE_updateState(&seqState->stateLL, &seqState->DStream);    /* <=  9 bits */
@@ -909,7 +986,8 @@ size_t ZSTD_execSequence(BYTE* op,
     /* copy Match */
     if (sequence.offset > (size_t)(oLitEnd - base)) {
         /* offset beyond prefix -> go into extDict */
-        if (sequence.offset > (size_t)(oLitEnd - vBase)) return ERROR(corruption_detected);
+        if (sequence.offset > (size_t)(oLitEnd - vBase))
+            return ERROR(corruption_detected);
         match = dictEnd + (match - base);
         if (match + sequence.matchLength <= dictEnd) {
             memmove(oLitEnd, match, sequence.matchLength);
@@ -977,9 +1055,12 @@ static size_t ZSTD_decompressSequences(
     const BYTE* const vBase = (const BYTE*) (dctx->vBase);
     const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
     int nbSeq;
+    DEBUGLOG(5, "ZSTD_decompressSequences");
 
     /* Build Decoding Tables */
     {   size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize);
+        DEBUGLOG(5, "ZSTD_decodeSeqHeaders: size=%u, nbSeq=%i",
+                    (U32)seqHSize, nbSeq);
         if (ZSTD_isError(seqHSize)) return seqHSize;
         ip += seqHSize;
     }
@@ -998,11 +1079,13 @@ static size_t ZSTD_decompressSequences(
             nbSeq--;
             {   seq_t const sequence = ZSTD_decodeSequence(&seqState);
                 size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd);
+                DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize);
                 if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
                 op += oneSeqSize;
         }   }
 
         /* check if reached exact end */
+        DEBUGLOG(5, "after decode loop, remaining nbSeq : %i", nbSeq);
         if (nbSeq) return ERROR(corruption_detected);
         /* save reps for next block */
         { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); }
@@ -1216,7 +1299,7 @@ static size_t ZSTD_decompressSequencesLong(
     const BYTE* const base = (const BYTE*) (dctx->base);
     const BYTE* const vBase = (const BYTE*) (dctx->vBase);
     const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
-    unsigned const windowSize = dctx->fParams.windowSize;
+    unsigned const windowSize32 = (unsigned)dctx->fParams.windowSize;
     int nbSeq;
 
     /* Build Decoding Tables */
@@ -1246,13 +1329,13 @@ static size_t ZSTD_decompressSequencesLong(
 
         /* prepare in advance */
         for (seqNb=0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && seqNb<seqAdvance; seqNb++) {
-            sequences[seqNb] = ZSTD_decodeSequenceLong(&seqState, windowSize);
+            sequences[seqNb] = ZSTD_decodeSequenceLong(&seqState, windowSize32);
         }
         if (seqNb<seqAdvance) return ERROR(corruption_detected);
 
         /* decode and decompress */
         for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && seqNb<nbSeq ; seqNb++) {
-            seq_t const sequence = ZSTD_decodeSequenceLong(&seqState, windowSize);
+            seq_t const sequence = ZSTD_decodeSequenceLong(&seqState, windowSize32);
             size_t const oneSeqSize = ZSTD_execSequenceLong(op, oend, sequences[(seqNb-ADVANCED_SEQS) & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd);
             if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
             ZSTD_PREFETCH(sequence.match);
@@ -1289,11 +1372,13 @@ static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
                       const void* src, size_t srcSize)
 {   /* blockType == blockCompressed */
     const BYTE* ip = (const BYTE*)src;
+    DEBUGLOG(5, "ZSTD_decompressBlock_internal");
 
-    if (srcSize >= ZSTD_BLOCKSIZE_ABSOLUTEMAX) return ERROR(srcSize_wrong);
+    if (srcSize >= ZSTD_BLOCKSIZE_MAX) return ERROR(srcSize_wrong);
 
     /* Decode literals section */
     {   size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize);
+        DEBUGLOG(5, "ZSTD_decodeLiteralsBlock : %u", (U32)litCSize);
         if (ZSTD_isError(litCSize)) return litCSize;
         ip += litCSize;
         srcSize -= litCSize;
@@ -1364,13 +1449,13 @@ size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize)
         const BYTE* ip = (const BYTE*)src;
         const BYTE* const ipstart = ip;
         size_t remainingSize = srcSize;
-        ZSTD_frameParams fParams;
+        ZSTD_frameHeader fParams;
 
         size_t const headerSize = ZSTD_frameHeaderSize(ip, remainingSize);
         if (ZSTD_isError(headerSize)) return headerSize;
 
         /* Frame Header */
-        {   size_t const ret = ZSTD_getFrameParams(&fParams, ip, remainingSize);
+        {   size_t const ret = ZSTD_getFrameHeader(&fParams, ip, remainingSize);
             if (ZSTD_isError(ret)) return ret;
             if (ret > 0) return ERROR(srcSize_wrong);
         }
@@ -1505,6 +1590,8 @@ static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx,
             size_t decodedSize;
             size_t const frameSize = ZSTD_findFrameCompressedSizeLegacy(src, srcSize);
             if (ZSTD_isError(frameSize)) return frameSize;
+            /* legacy support is incompatible with static dctx */
+            if (dctx->staticSize) return ERROR(memory_allocation);
 
             decodedSize = ZSTD_decompressLegacy(dst, dstCapacity, src, frameSize, dict, dictSize);
 
@@ -1540,7 +1627,7 @@ static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx,
 
         if (ddict) {
             /* we were called from ZSTD_decompress_usingDDict */
-            ZSTD_refDDict(dctx, ddict);
+            CHECK_F(ZSTD_decompressBegin_usingDDict(dctx, ddict));
         } else {
             /* this will initialize correctly with no dict if dict == NULL, so
              * use this in all cases but ddict */
@@ -1580,7 +1667,7 @@ size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const
 
 size_t ZSTD_decompress(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
 {
-#if defined(ZSTD_HEAPMODE) && (ZSTD_HEAPMODE==1)
+#if defined(ZSTD_HEAPMODE) && (ZSTD_HEAPMODE>=1)
     size_t regenSize;
     ZSTD_DCtx* const dctx = ZSTD_createDCtx();
     if (dctx==NULL) return ERROR(memory_allocation);
@@ -1604,6 +1691,7 @@ ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx) {
     switch(dctx->stage)
     {
     default:   /* should not happen */
+        assert(0);
     case ZSTDds_getFrameHeaderSize:
     case ZSTDds_decodeFrameHeader:
         return ZSTDnit_frameHeader;
@@ -1621,21 +1709,24 @@ ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx) {
     }
 }
 
-int ZSTD_isSkipFrame(ZSTD_DCtx* dctx) { return dctx->stage == ZSTDds_skipFrame; }   /* for zbuff */
+static int ZSTD_isSkipFrame(ZSTD_DCtx* dctx) { return dctx->stage == ZSTDds_skipFrame; }
 
 /** ZSTD_decompressContinue() :
-*   @return : nb of bytes generated into `dst` (necessarily <= `dstCapacity)
-*             or an error code, which can be tested using ZSTD_isError() */
+ *  srcSize : must be the exact nb of bytes expected (see ZSTD_nextSrcSizeToDecompress())
+ *  @return : nb of bytes generated into `dst` (necessarily <= `dstCapacity)
+ *            or an error code, which can be tested using ZSTD_isError() */
 size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
 {
+    DEBUGLOG(5, "ZSTD_decompressContinue");
     /* Sanity check */
-    if (srcSize != dctx->expected) return ERROR(srcSize_wrong);
+    if (srcSize != dctx->expected) return ERROR(srcSize_wrong);   /* unauthorized */
     if (dstCapacity) ZSTD_checkContinuity(dctx, dst);
 
     switch (dctx->stage)
     {
     case ZSTDds_getFrameHeaderSize :
-        if (srcSize != ZSTD_frameHeaderSize_prefix) return ERROR(srcSize_wrong);      /* impossible */
+        if (srcSize != ZSTD_frameHeaderSize_prefix) return ERROR(srcSize_wrong);      /* unauthorized */
+        assert(src != NULL);
         if ((MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {        /* skippable frame */
             memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix);
             dctx->expected = ZSTD_skippableHeaderSize - ZSTD_frameHeaderSize_prefix;  /* magic number + skippable frame length */
@@ -1653,6 +1744,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
         dctx->expected = 0;   /* not necessary to copy more */
 
     case ZSTDds_decodeFrameHeader:
+        assert(src != NULL);
         memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected);
         CHECK_F(ZSTD_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize));
         dctx->expected = ZSTD_blockHeaderSize;
@@ -1680,17 +1772,19 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
                     dctx->stage = ZSTDds_getFrameHeaderSize;
                 }
             } else {
-                dctx->expected = 3;  /* go directly to next header */
+                dctx->expected = ZSTD_blockHeaderSize;  /* jump to next header */
                 dctx->stage = ZSTDds_decodeBlockHeader;
             }
             return 0;
         }
     case ZSTDds_decompressLastBlock:
     case ZSTDds_decompressBlock:
+        DEBUGLOG(5, "case ZSTDds_decompressBlock");
         {   size_t rSize;
             switch(dctx->bType)
             {
             case bt_compressed:
+                DEBUGLOG(5, "case bt_compressed");
                 rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize);
                 break;
             case bt_raw :
@@ -1730,7 +1824,8 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
             return 0;
         }
     case ZSTDds_decodeSkippableHeader:
-        {   memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected);
+        {   assert(src != NULL);
+            memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected);
             dctx->expected = MEM_readLE32(dctx->headerBuffer + 4);
             dctx->stage = ZSTDds_skipFrame;
             return 0;
@@ -1767,7 +1862,9 @@ static size_t ZSTD_loadEntropy(ZSTD_entropyTables_t* entropy, const void* const
     dictPtr += 8;   /* skip header = magic + dictID */
 
 
-    {   size_t const hSize = HUF_readDTableX4(entropy->hufTable, dictPtr, dictEnd-dictPtr);
+    {   size_t const hSize = HUF_readDTableX4_wksp(
+            entropy->hufTable, dictPtr, dictEnd - dictPtr,
+            entropy->workspace, sizeof(entropy->workspace));
         if (HUF_isError(hSize)) return ERROR(dictionary_corrupted);
         dictPtr += hSize;
     }
@@ -1815,7 +1912,7 @@ static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx* dctx, const void* dict
 {
     if (dictSize < 8) return ZSTD_refDictContent(dctx, dict, dictSize);
     {   U32 const magic = MEM_readLE32(dict);
-        if (magic != ZSTD_DICT_MAGIC) {
+        if (magic != ZSTD_MAGIC_DICTIONARY) {
             return ZSTD_refDictContent(dctx, dict, dictSize);   /* pure content mode */
     }   }
     dctx->dictID = MEM_readLE32((const char*)dict + 4);
@@ -1862,10 +1959,10 @@ static size_t ZSTD_DDictDictSize(const ZSTD_DDict* ddict)
     return ddict->dictSize;
 }
 
-static void ZSTD_refDDict(ZSTD_DCtx* dstDCtx, const ZSTD_DDict* ddict)
+size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dstDCtx, const ZSTD_DDict* ddict)
 {
-    ZSTD_decompressBegin(dstDCtx);  /* init */
-    if (ddict) {   /* support refDDict on NULL */
+    CHECK_F(ZSTD_decompressBegin(dstDCtx));
+    if (ddict) {   /* support begin on NULL */
         dstDCtx->dictID = ddict->dictID;
         dstDCtx->base = ddict->dictContent;
         dstDCtx->vBase = ddict->dictContent;
@@ -1886,6 +1983,7 @@ static void ZSTD_refDDict(ZSTD_DCtx* dstDCtx, const ZSTD_DDict* ddict)
             dstDCtx->fseEntropy = 0;
         }
     }
+    return 0;
 }
 
 static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict* ddict)
@@ -1894,7 +1992,7 @@ static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict* ddict)
     ddict->entropyPresent = 0;
     if (ddict->dictSize < 8) return 0;
     {   U32 const magic = MEM_readLE32(ddict->dictContent);
-        if (magic != ZSTD_DICT_MAGIC) return 0;   /* pure content mode */
+        if (magic != ZSTD_MAGIC_DICTIONARY) return 0;   /* pure content mode */
     }
     ddict->dictID = MEM_readLE32((const char*)ddict->dictContent + 4);
 
@@ -1905,33 +2003,39 @@ static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict* ddict)
 }
 
 
+static size_t ZSTD_initDDict_internal(ZSTD_DDict* ddict, const void* dict, size_t dictSize, unsigned byReference)
+{
+    if ((byReference) || (!dict) || (!dictSize)) {
+        ddict->dictBuffer = NULL;
+        ddict->dictContent = dict;
+    } else {
+        void* const internalBuffer = ZSTD_malloc(dictSize, ddict->cMem);
+        ddict->dictBuffer = internalBuffer;
+        ddict->dictContent = internalBuffer;
+        if (!internalBuffer) return ERROR(memory_allocation);
+        memcpy(internalBuffer, dict, dictSize);
+    }
+    ddict->dictSize = dictSize;
+    ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001);  /* cover both little and big endian */
+
+    /* parse dictionary content */
+    CHECK_F( ZSTD_loadEntropy_inDDict(ddict) );
+
+    return 0;
+}
+
 ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize, unsigned byReference, ZSTD_customMem customMem)
 {
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
 
     {   ZSTD_DDict* const ddict = (ZSTD_DDict*) ZSTD_malloc(sizeof(ZSTD_DDict), customMem);
         if (!ddict) return NULL;
         ddict->cMem = customMem;
 
-        if ((byReference) || (!dict) || (!dictSize)) {
-            ddict->dictBuffer = NULL;
-            ddict->dictContent = dict;
-        } else {
-            void* const internalBuffer = ZSTD_malloc(dictSize, customMem);
-            if (!internalBuffer) { ZSTD_freeDDict(ddict); return NULL; }
-            memcpy(internalBuffer, dict, dictSize);
-            ddict->dictBuffer = internalBuffer;
-            ddict->dictContent = internalBuffer;
+        if (ZSTD_isError( ZSTD_initDDict_internal(ddict, dict, dictSize, byReference) )) {
+            ZSTD_freeDDict(ddict);
+            return NULL;
         }
-        ddict->dictSize = dictSize;
-        ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001);  /* cover both little and big endian */
-        /* parse dictionary content */
-        {   size_t const errorCode = ZSTD_loadEntropy_inDDict(ddict);
-            if (ZSTD_isError(errorCode)) {
-                ZSTD_freeDDict(ddict);
-                return NULL;
-        }   }
 
         return ddict;
     }
@@ -1947,7 +2051,6 @@ ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize)
     return ZSTD_createDDict_advanced(dict, dictSize, 0, allocator);
 }
 
-
 /*! ZSTD_createDDict_byReference() :
  *  Create a digested dictionary, to start decompression without startup delay.
  *  Dictionary content is simply referenced, it will be accessed during decompression.
@@ -1959,6 +2062,26 @@ ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize
 }
 
 
+ZSTD_DDict* ZSTD_initStaticDDict(void* workspace, size_t workspaceSize,
+                                 const void* dict, size_t dictSize,
+                                 unsigned byReference)
+{
+    size_t const neededSpace = sizeof(ZSTD_DDict) + (byReference ? 0 : dictSize);
+    ZSTD_DDict* const ddict = (ZSTD_DDict*)workspace;
+    assert(workspace != NULL);
+    assert(dict != NULL);
+    if ((size_t)workspace & 7) return NULL;  /* 8-aligned */
+    if (workspaceSize < neededSpace) return NULL;
+    if (!byReference) {
+        memcpy(ddict+1, dict, dictSize);  /* local copy */
+        dict = ddict+1;
+    }
+    if (ZSTD_isError( ZSTD_initDDict_internal(ddict, dict, dictSize, 1 /* byRef */) ))
+        return NULL;
+    return ddict;
+}
+
+
 size_t ZSTD_freeDDict(ZSTD_DDict* ddict)
 {
     if (ddict==NULL) return 0;   /* support free on NULL */
@@ -1969,6 +2092,14 @@ size_t ZSTD_freeDDict(ZSTD_DDict* ddict)
     }
 }
 
+/*! ZSTD_estimateDDictSize() :
+ *  Estimate amount of memory that will be needed to create a dictionary for decompression.
+ *  Note : dictionary created "byReference" are smaller */
+size_t ZSTD_estimateDDictSize(size_t dictSize, unsigned byReference)
+{
+    return sizeof(ZSTD_DDict) + (byReference ? 0 : dictSize);
+}
+
 size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict)
 {
     if (ddict==NULL) return 0;   /* support sizeof on NULL */
@@ -1982,7 +2113,7 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict)
 unsigned ZSTD_getDictID_fromDict(const void* dict, size_t dictSize)
 {
     if (dictSize < 8) return 0;
-    if (MEM_readLE32(dict) != ZSTD_DICT_MAGIC) return 0;
+    if (MEM_readLE32(dict) != ZSTD_MAGIC_DICTIONARY) return 0;
     return MEM_readLE32((const char*)dict + 4);
 }
 
@@ -2008,11 +2139,11 @@ unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict)
  *    Note : possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`.
  *  - This is not a Zstandard frame.
  *  When identifying the exact failure cause, it's possible to use
- *  ZSTD_getFrameParams(), which will provide a more precise error code. */
+ *  ZSTD_getFrameHeader(), which will provide a more precise error code. */
 unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize)
 {
-    ZSTD_frameParams zfp = { 0 , 0 , 0 , 0 };
-    size_t const hError = ZSTD_getFrameParams(&zfp, src, srcSize);
+    ZSTD_frameHeader zfp = { 0 , 0 , 0 , 0 };
+    size_t const hError = ZSTD_getFrameHeader(&zfp, src, srcSize);
     if (ZSTD_isError(hError)) return 0;
     return zfp.dictID;
 }
@@ -2037,88 +2168,35 @@ size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
 *   Streaming decompression
 *====================================*/
 
-typedef enum { zdss_init, zdss_loadHeader,
-               zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage;
-
-/* *** Resource management *** */
-struct ZSTD_DStream_s {
-    ZSTD_DCtx* dctx;
-    ZSTD_DDict* ddictLocal;
-    const ZSTD_DDict* ddict;
-    ZSTD_frameParams fParams;
-    ZSTD_dStreamStage stage;
-    char*  inBuff;
-    size_t inBuffSize;
-    size_t inPos;
-    size_t maxWindowSize;
-    char*  outBuff;
-    size_t outBuffSize;
-    size_t outStart;
-    size_t outEnd;
-    size_t blockSize;
-    BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX];   /* tmp buffer to store frame header */
-    size_t lhSize;
-    ZSTD_customMem customMem;
-    void* legacyContext;
-    U32 previousLegacyVersion;
-    U32 legacyVersion;
-    U32 hostageByte;
-};   /* typedef'd to ZSTD_DStream within "zstd.h" */
-
-
 ZSTD_DStream* ZSTD_createDStream(void)
 {
-    return ZSTD_createDStream_advanced(defaultCustomMem);
+    return ZSTD_createDStream_advanced(ZSTD_defaultCMem);
 }
 
-ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem)
+ZSTD_DStream* ZSTD_initStaticDStream(void *workspace, size_t workspaceSize)
 {
-    ZSTD_DStream* zds;
-
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    return ZSTD_initStaticDCtx(workspace, workspaceSize);
+}
 
-    zds = (ZSTD_DStream*) ZSTD_malloc(sizeof(ZSTD_DStream), customMem);
-    if (zds==NULL) return NULL;
-    memset(zds, 0, sizeof(ZSTD_DStream));
-    memcpy(&zds->customMem, &customMem, sizeof(ZSTD_customMem));
-    zds->dctx = ZSTD_createDCtx_advanced(customMem);
-    if (zds->dctx == NULL) { ZSTD_freeDStream(zds); return NULL; }
-    zds->stage = zdss_init;
-    zds->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT;
-    return zds;
+ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem)
+{
+    return ZSTD_createDCtx_advanced(customMem);
 }
 
 size_t ZSTD_freeDStream(ZSTD_DStream* zds)
 {
-    if (zds==NULL) return 0;   /* support free on null */
-    {   ZSTD_customMem const cMem = zds->customMem;
-        ZSTD_freeDCtx(zds->dctx);
-        zds->dctx = NULL;
-        ZSTD_freeDDict(zds->ddictLocal);
-        zds->ddictLocal = NULL;
-        ZSTD_free(zds->inBuff, cMem);
-        zds->inBuff = NULL;
-        ZSTD_free(zds->outBuff, cMem);
-        zds->outBuff = NULL;
-#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1)
-        if (zds->legacyContext)
-            ZSTD_freeLegacyStreamContext(zds->legacyContext, zds->previousLegacyVersion);
-#endif
-        ZSTD_free(zds, cMem);
-        return 0;
-    }
+    return ZSTD_freeDCtx(zds);
 }
 
 
 /* *** Initialization *** */
 
-size_t ZSTD_DStreamInSize(void)  { return ZSTD_BLOCKSIZE_ABSOLUTEMAX + ZSTD_blockHeaderSize; }
-size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
+size_t ZSTD_DStreamInSize(void)  { return ZSTD_BLOCKSIZE_MAX + ZSTD_blockHeaderSize; }
+size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_MAX; }
 
 size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize)
 {
-    zds->stage = zdss_loadHeader;
+    zds->streamStage = zdss_loadHeader;
     zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
     ZSTD_freeDDict(zds->ddictLocal);
     if (dict && dictSize >= 8) {
@@ -2147,7 +2225,7 @@ size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict)
 
 size_t ZSTD_resetDStream(ZSTD_DStream* zds)
 {
-    zds->stage = zdss_loadHeader;
+    zds->streamStage = zdss_loadHeader;
     zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
     zds->legacyVersion = 0;
     zds->hostageByte = 0;
@@ -2168,11 +2246,24 @@ size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds,
 
 size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds)
 {
-    if (zds==NULL) return 0;   /* support sizeof NULL */
-    return sizeof(*zds)
-           + ZSTD_sizeof_DCtx(zds->dctx)
-           + ZSTD_sizeof_DDict(zds->ddictLocal)
-           + zds->inBuffSize + zds->outBuffSize;
+    return ZSTD_sizeof_DCtx(zds);
+}
+
+size_t ZSTD_estimateDStreamSize(size_t windowSize)
+{
+    size_t const blockSize = MIN(windowSize, ZSTD_BLOCKSIZE_MAX);
+    size_t const inBuffSize = blockSize;  /* no block can be larger */
+    size_t const outBuffSize = windowSize + blockSize + (WILDCOPY_OVERLENGTH * 2);
+    return sizeof(ZSTD_DStream) + ZSTD_estimateDCtxSize() + inBuffSize + outBuffSize;
+}
+
+ZSTDLIB_API size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize)
+{
+    ZSTD_frameHeader fh;
+    size_t const err = ZSTD_getFrameHeader(&fh, src, srcSize);
+    if (ZSTD_isError(err)) return err;
+    if (err>0) return ERROR(srcSize_wrong);
+    return ZSTD_estimateDStreamSize(fh.windowSize);
 }
 
 
@@ -2196,44 +2287,55 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
     char* op = ostart;
     U32 someMoreWork = 1;
 
+    DEBUGLOG(5, "ZSTD_decompressStream");
+    DEBUGLOG(5, "input size : %u", (U32)(input->size - input->pos));
 #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1)
-    if (zds->legacyVersion)
+    if (zds->legacyVersion) {
+        /* legacy support is incompatible with static dctx */
+        if (zds->staticSize) return ERROR(memory_allocation);
         return ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input);
+    }
 #endif
 
     while (someMoreWork) {
-        switch(zds->stage)
+        switch(zds->streamStage)
         {
         case zdss_init :
             ZSTD_resetDStream(zds);   /* transparent reset on starting decoding a new frame */
             /* fall-through */
 
         case zdss_loadHeader :
-            {   size_t const hSize = ZSTD_getFrameParams(&zds->fParams, zds->headerBuffer, zds->lhSize);
-                if (ZSTD_isError(hSize))
+            {   size_t const hSize = ZSTD_getFrameHeader(&zds->fParams, zds->headerBuffer, zds->lhSize);
+                if (ZSTD_isError(hSize)) {
 #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1)
-                {   U32 const legacyVersion = ZSTD_isLegacy(istart, iend-istart);
+                    U32 const legacyVersion = ZSTD_isLegacy(istart, iend-istart);
                     if (legacyVersion) {
                         const void* const dict = zds->ddict ? zds->ddict->dictContent : NULL;
                         size_t const dictSize = zds->ddict ? zds->ddict->dictSize : 0;
+                        /* legacy support is incompatible with static dctx */
+                        if (zds->staticSize) return ERROR(memory_allocation);
                         CHECK_F(ZSTD_initLegacyStream(&zds->legacyContext, zds->previousLegacyVersion, legacyVersion,
                                                        dict, dictSize));
                         zds->legacyVersion = zds->previousLegacyVersion = legacyVersion;
                         return ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input);
                     } else {
                         return hSize; /* error */
-                }   }
+                    }
 #else
-                return hSize;
+                    return hSize;
 #endif
+                }
                 if (hSize != 0) {   /* need more input */
                     size_t const toLoad = hSize - zds->lhSize;   /* if hSize!=0, hSize > zds->lhSize */
                     if (toLoad > (size_t)(iend-ip)) {   /* not enough input to load full header */
-                        memcpy(zds->headerBuffer + zds->lhSize, ip, iend-ip);
-                        zds->lhSize += iend-ip;
+                        if (iend-ip > 0) {
+                            memcpy(zds->headerBuffer + zds->lhSize, ip, iend-ip);
+                            zds->lhSize += iend-ip;
+                        }
                         input->pos = input->size;
                         return (MAX(ZSTD_frameHeaderSize_min, hSize) - zds->lhSize) + ZSTD_blockHeaderSize;   /* remaining header bytes + next block header */
                     }
+                    assert(ip != NULL);
                     memcpy(zds->headerBuffer + zds->lhSize, ip, toLoad); zds->lhSize = hSize; ip += toLoad;
                     break;
             }   }
@@ -2243,74 +2345,90 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
                 && (U64)(size_t)(oend-op) >= zds->fParams.frameContentSize) {
                 size_t const cSize = ZSTD_findFrameCompressedSize(istart, iend-istart);
                 if (cSize <= (size_t)(iend-istart)) {
-                    size_t const decompressedSize = ZSTD_decompress_usingDDict(zds->dctx, op, oend-op, istart, cSize, zds->ddict);
+                    size_t const decompressedSize = ZSTD_decompress_usingDDict(zds, op, oend-op, istart, cSize, zds->ddict);
                     if (ZSTD_isError(decompressedSize)) return decompressedSize;
                     ip = istart + cSize;
                     op += decompressedSize;
-                    zds->dctx->expected = 0;
-                    zds->stage = zdss_init;
+                    zds->expected = 0;
+                    zds->streamStage = zdss_init;
                     someMoreWork = 0;
                     break;
             }   }
 
-            /* Consume header */
-            ZSTD_refDDict(zds->dctx, zds->ddict);
-            {   size_t const h1Size = ZSTD_nextSrcSizeToDecompress(zds->dctx);  /* == ZSTD_frameHeaderSize_prefix */
-                CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer, h1Size));
-                {   size_t const h2Size = ZSTD_nextSrcSizeToDecompress(zds->dctx);
-                    CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer+h1Size, h2Size));
-            }   }
+            /* Consume header (see ZSTDds_decodeFrameHeader) */
+            DEBUGLOG(4, "Consume header");
+            CHECK_F(ZSTD_decompressBegin_usingDDict(zds, zds->ddict));
+
+            if ((MEM_readLE32(zds->headerBuffer) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {  /* skippable frame */
+                zds->expected = MEM_readLE32(zds->headerBuffer + 4);
+                zds->stage = ZSTDds_skipFrame;
+            } else {
+                CHECK_F(ZSTD_decodeFrameHeader(zds, zds->headerBuffer, zds->lhSize));
+                zds->expected = ZSTD_blockHeaderSize;
+                zds->stage = ZSTDds_decodeBlockHeader;
+            }
 
+            /* control buffer memory usage */
+            DEBUGLOG(4, "Control max buffer memory usage");
             zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN);
             if (zds->fParams.windowSize > zds->maxWindowSize) return ERROR(frameParameter_windowTooLarge);
 
             /* Adapt buffer sizes to frame header instructions */
-            {   size_t const blockSize = MIN(zds->fParams.windowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX);
+            {   size_t const blockSize = MIN(zds->fParams.windowSize, ZSTD_BLOCKSIZE_MAX);
                 size_t const neededOutSize = zds->fParams.windowSize + blockSize + WILDCOPY_OVERLENGTH * 2;
                 zds->blockSize = blockSize;
-                if (zds->inBuffSize < blockSize) {
-                    ZSTD_free(zds->inBuff, zds->customMem);
-                    zds->inBuffSize = 0;
-                    zds->inBuff = (char*)ZSTD_malloc(blockSize, zds->customMem);
-                    if (zds->inBuff == NULL) return ERROR(memory_allocation);
+                if ((zds->inBuffSize < blockSize) || (zds->outBuffSize < neededOutSize)) {
+                    size_t const bufferSize = blockSize + neededOutSize;
+                    DEBUGLOG(4, "inBuff  : from %u to %u",
+                                (U32)zds->inBuffSize, (U32)blockSize);
+                    DEBUGLOG(4, "outBuff : from %u to %u",
+                                (U32)zds->outBuffSize, (U32)neededOutSize);
+                    if (zds->staticSize) {  /* static DCtx */
+                        DEBUGLOG(4, "staticSize : %u", (U32)zds->staticSize);
+                        assert(zds->staticSize >= sizeof(ZSTD_DCtx));  /* controlled at init */
+                        if (bufferSize > zds->staticSize - sizeof(ZSTD_DCtx))
+                            return ERROR(memory_allocation);
+                    } else {
+                        ZSTD_free(zds->inBuff, zds->customMem);
+                        zds->inBuffSize = 0;
+                        zds->outBuffSize = 0;
+                        zds->inBuff = (char*)ZSTD_malloc(bufferSize, zds->customMem);
+                        if (zds->inBuff == NULL) return ERROR(memory_allocation);
+                    }
                     zds->inBuffSize = blockSize;
-                }
-                if (zds->outBuffSize < neededOutSize) {
-                    ZSTD_free(zds->outBuff, zds->customMem);
-                    zds->outBuffSize = 0;
-                    zds->outBuff = (char*)ZSTD_malloc(neededOutSize, zds->customMem);
-                    if (zds->outBuff == NULL) return ERROR(memory_allocation);
+                    zds->outBuff = zds->inBuff + zds->inBuffSize;
                     zds->outBuffSize = neededOutSize;
             }   }
-            zds->stage = zdss_read;
+            zds->streamStage = zdss_read;
             /* pass-through */
 
         case zdss_read:
-            {   size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx);
+            DEBUGLOG(5, "stage zdss_read");
+            {   size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds);
+                DEBUGLOG(5, "neededInSize = %u", (U32)neededInSize);
                 if (neededInSize==0) {  /* end of frame */
-                    zds->stage = zdss_init;
+                    zds->streamStage = zdss_init;
                     someMoreWork = 0;
                     break;
                 }
                 if ((size_t)(iend-ip) >= neededInSize) {  /* decode directly from src */
-                    const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx);
-                    size_t const decodedSize = ZSTD_decompressContinue(zds->dctx,
+                    int const isSkipFrame = ZSTD_isSkipFrame(zds);
+                    size_t const decodedSize = ZSTD_decompressContinue(zds,
                         zds->outBuff + zds->outStart, (isSkipFrame ? 0 : zds->outBuffSize - zds->outStart),
                         ip, neededInSize);
                     if (ZSTD_isError(decodedSize)) return decodedSize;
                     ip += neededInSize;
                     if (!decodedSize && !isSkipFrame) break;   /* this was just a header */
                     zds->outEnd = zds->outStart + decodedSize;
-                    zds->stage = zdss_flush;
+                    zds->streamStage = zdss_flush;
                     break;
-                }
-                if (ip==iend) { someMoreWork = 0; break; }   /* no more input */
-                zds->stage = zdss_load;
-                /* pass-through */
-            }
+            }   }
+            if (ip==iend) { someMoreWork = 0; break; }   /* no more input */
+            zds->streamStage = zdss_load;
+            /* pass-through */
 
         case zdss_load:
-            {   size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx);
+            {   size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds);
                 size_t const toLoad = neededInSize - zds->inPos;   /* should always be <= remaining space within inBuff */
                 size_t loadedSize;
                 if (toLoad > zds->inBuffSize - zds->inPos) return ERROR(corruption_detected);   /* should never happen */
@@ -2320,17 +2438,17 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
                 if (loadedSize < toLoad) { someMoreWork = 0; break; }   /* not enough input, wait for more */
 
                 /* decode loaded input */
-                {  const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx);
-                   size_t const decodedSize = ZSTD_decompressContinue(zds->dctx,
+                {  const int isSkipFrame = ZSTD_isSkipFrame(zds);
+                   size_t const decodedSize = ZSTD_decompressContinue(zds,
                         zds->outBuff + zds->outStart, zds->outBuffSize - zds->outStart,
                         zds->inBuff, neededInSize);
                     if (ZSTD_isError(decodedSize)) return decodedSize;
                     zds->inPos = 0;   /* input is consumed */
-                    if (!decodedSize && !isSkipFrame) { zds->stage = zdss_read; break; }   /* this was just a header */
+                    if (!decodedSize && !isSkipFrame) { zds->streamStage = zdss_read; break; }   /* this was just a header */
                     zds->outEnd = zds->outStart +  decodedSize;
-                    zds->stage = zdss_flush;
-                    /* pass-through */
             }   }
+            zds->streamStage = zdss_flush;
+            /* pass-through */
 
         case zdss_flush:
             {   size_t const toFlushSize = zds->outEnd - zds->outStart;
@@ -2338,37 +2456,41 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
                 op += flushedSize;
                 zds->outStart += flushedSize;
                 if (flushedSize == toFlushSize) {  /* flush completed */
-                    zds->stage = zdss_read;
+                    zds->streamStage = zdss_read;
                     if (zds->outStart + zds->blockSize > zds->outBuffSize)
                         zds->outStart = zds->outEnd = 0;
                     break;
-                }
-                /* cannot complete flush */
-                someMoreWork = 0;
-                break;
-            }
+            }   }
+            /* cannot complete flush */
+            someMoreWork = 0;
+            break;
+
         default: return ERROR(GENERIC);   /* impossible */
     }   }
 
     /* result */
     input->pos += (size_t)(ip-istart);
     output->pos += (size_t)(op-ostart);
-    {   size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds->dctx);
+    {   size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds);
         if (!nextSrcSizeHint) {   /* frame fully decoded */
             if (zds->outEnd == zds->outStart) {  /* output fully flushed */
                 if (zds->hostageByte) {
-                    if (input->pos >= input->size) { zds->stage = zdss_read; return 1; }  /* can't release hostage (not present) */
+                    if (input->pos >= input->size) {
+                        /* can't release hostage (not present) */
+                        zds->streamStage = zdss_read;
+                        return 1;
+                    }
                     input->pos++;  /* release hostage */
-                }
+                }   /* zds->hostageByte */
                 return 0;
-            }
+            }  /* zds->outEnd == zds->outStart */
             if (!zds->hostageByte) { /* output not fully flushed; keep last byte as hostage; will be released when all output is flushed */
                 input->pos--;   /* note : pos > 0, otherwise, impossible to finish reading last block */
                 zds->hostageByte=1;
             }
             return 1;
-        }
-        nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds->dctx) == ZSTDnit_block);   /* preload header of next block */
+        }  /* nextSrcSizeHint==0 */
+        nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds) == ZSTDnit_block);   /* preload header of next block */
         if (zds->inPos > nextSrcSizeHint) return ERROR(GENERIC);   /* should never happen */
         nextSrcSizeHint -= zds->inPos;   /* already loaded*/
         return nextSrcSizeHint;
diff --git a/lib/dictBuilder/cover.c b/lib/dictBuilder/cover.c
index 1863c8f34542..06c1b9fadb7a 100644
--- a/lib/dictBuilder/cover.c
+++ b/lib/dictBuilder/cover.c
@@ -398,7 +398,8 @@ typedef struct {
  */
 static COVER_segment_t COVER_selectSegment(const COVER_ctx_t *ctx, U32 *freqs,
                                            COVER_map_t *activeDmers, U32 begin,
-                                           U32 end, COVER_params_t parameters) {
+                                           U32 end,
+                                           ZDICT_cover_params_t parameters) {
   /* Constants */
   const U32 k = parameters.k;
   const U32 d = parameters.d;
@@ -478,7 +479,7 @@ static COVER_segment_t COVER_selectSegment(const COVER_ctx_t *ctx, U32 *freqs,
  * Check the validity of the parameters.
  * Returns non-zero if the parameters are valid and 0 otherwise.
  */
-static int COVER_checkParameters(COVER_params_t parameters) {
+static int COVER_checkParameters(ZDICT_cover_params_t parameters) {
   /* k and d are required parameters */
   if (parameters.d == 0 || parameters.k == 0) {
     return 0;
@@ -600,7 +601,7 @@ static int COVER_ctx_init(COVER_ctx_t *ctx, const void *samplesBuffer,
 static size_t COVER_buildDictionary(const COVER_ctx_t *ctx, U32 *freqs,
                                     COVER_map_t *activeDmers, void *dictBuffer,
                                     size_t dictBufferCapacity,
-                                    COVER_params_t parameters) {
+                                    ZDICT_cover_params_t parameters) {
   BYTE *const dict = (BYTE *)dictBuffer;
   size_t tail = dictBufferCapacity;
   /* Divide the data up into epochs of equal size.
@@ -639,22 +640,10 @@ static size_t COVER_buildDictionary(const COVER_ctx_t *ctx, U32 *freqs,
   return tail;
 }
 
-/**
- * Translate from COVER_params_t to ZDICT_params_t required for finalizing the
- * dictionary.
- */
-static ZDICT_params_t COVER_translateParams(COVER_params_t parameters) {
-  ZDICT_params_t zdictParams;
-  memset(&zdictParams, 0, sizeof(zdictParams));
-  zdictParams.notificationLevel = 1;
-  zdictParams.dictID = parameters.dictID;
-  zdictParams.compressionLevel = parameters.compressionLevel;
-  return zdictParams;
-}
-
-ZDICTLIB_API size_t COVER_trainFromBuffer(
+ZDICTLIB_API size_t ZDICT_trainFromBuffer_cover(
     void *dictBuffer, size_t dictBufferCapacity, const void *samplesBuffer,
-    const size_t *samplesSizes, unsigned nbSamples, COVER_params_t parameters) {
+    const size_t *samplesSizes, unsigned nbSamples,
+    ZDICT_cover_params_t parameters) {
   BYTE *const dict = (BYTE *)dictBuffer;
   COVER_ctx_t ctx;
   COVER_map_t activeDmers;
@@ -673,7 +662,7 @@ ZDICTLIB_API size_t COVER_trainFromBuffer(
     return ERROR(dstSize_tooSmall);
   }
   /* Initialize global data */
-  g_displayLevel = parameters.notificationLevel;
+  g_displayLevel = parameters.zParams.notificationLevel;
   /* Initialize context and activeDmers */
   if (!COVER_ctx_init(&ctx, samplesBuffer, samplesSizes, nbSamples,
                       parameters.d)) {
@@ -690,10 +679,9 @@ ZDICTLIB_API size_t COVER_trainFromBuffer(
     const size_t tail =
         COVER_buildDictionary(&ctx, ctx.freqs, &activeDmers, dictBuffer,
                               dictBufferCapacity, parameters);
-    ZDICT_params_t zdictParams = COVER_translateParams(parameters);
     const size_t dictionarySize = ZDICT_finalizeDictionary(
         dict, dictBufferCapacity, dict + tail, dictBufferCapacity - tail,
-        samplesBuffer, samplesSizes, nbSamples, zdictParams);
+        samplesBuffer, samplesSizes, nbSamples, parameters.zParams);
     if (!ZSTD_isError(dictionarySize)) {
       DISPLAYLEVEL(2, "Constructed dictionary of size %u\n",
                    (U32)dictionarySize);
@@ -718,7 +706,7 @@ typedef struct COVER_best_s {
   size_t liveJobs;
   void *dict;
   size_t dictSize;
-  COVER_params_t parameters;
+  ZDICT_cover_params_t parameters;
   size_t compressedSize;
 } COVER_best_t;
 
@@ -786,7 +774,7 @@ static void COVER_best_start(COVER_best_t *best) {
  * If this dictionary is the best so far save it and its parameters.
  */
 static void COVER_best_finish(COVER_best_t *best, size_t compressedSize,
-                              COVER_params_t parameters, void *dict,
+                              ZDICT_cover_params_t parameters, void *dict,
                               size_t dictSize) {
   if (!best) {
     return;
@@ -830,7 +818,7 @@ typedef struct COVER_tryParameters_data_s {
   const COVER_ctx_t *ctx;
   COVER_best_t *best;
   size_t dictBufferCapacity;
-  COVER_params_t parameters;
+  ZDICT_cover_params_t parameters;
 } COVER_tryParameters_data_t;
 
 /**
@@ -842,7 +830,7 @@ static void COVER_tryParameters(void *opaque) {
   /* Save parameters as local variables */
   COVER_tryParameters_data_t *const data = (COVER_tryParameters_data_t *)opaque;
   const COVER_ctx_t *const ctx = data->ctx;
-  const COVER_params_t parameters = data->parameters;
+  const ZDICT_cover_params_t parameters = data->parameters;
   size_t dictBufferCapacity = data->dictBufferCapacity;
   size_t totalCompressedSize = ERROR(GENERIC);
   /* Allocate space for hash table, dict, and freqs */
@@ -863,10 +851,10 @@ static void COVER_tryParameters(void *opaque) {
   {
     const size_t tail = COVER_buildDictionary(ctx, freqs, &activeDmers, dict,
                                               dictBufferCapacity, parameters);
-    const ZDICT_params_t zdictParams = COVER_translateParams(parameters);
     dictBufferCapacity = ZDICT_finalizeDictionary(
         dict, dictBufferCapacity, dict + tail, dictBufferCapacity - tail,
-        ctx->samples, ctx->samplesSizes, (unsigned)ctx->nbSamples, zdictParams);
+        ctx->samples, ctx->samplesSizes, (unsigned)ctx->nbSamples,
+        parameters.zParams);
     if (ZDICT_isError(dictBufferCapacity)) {
       DISPLAYLEVEL(1, "Failed to finalize dictionary\n");
       goto _cleanup;
@@ -892,8 +880,8 @@ static void COVER_tryParameters(void *opaque) {
     }
     /* Create the cctx and cdict */
     cctx = ZSTD_createCCtx();
-    cdict =
-        ZSTD_createCDict(dict, dictBufferCapacity, parameters.compressionLevel);
+    cdict = ZSTD_createCDict(dict, dictBufferCapacity,
+                             parameters.zParams.compressionLevel);
     if (!dst || !cctx || !cdict) {
       goto _compressCleanup;
     }
@@ -930,12 +918,10 @@ _cleanup:
   }
 }
 
-ZDICTLIB_API size_t COVER_optimizeTrainFromBuffer(void *dictBuffer,
-                                                  size_t dictBufferCapacity,
-                                                  const void *samplesBuffer,
-                                                  const size_t *samplesSizes,
-                                                  unsigned nbSamples,
-                                                  COVER_params_t *parameters) {
+ZDICTLIB_API size_t ZDICT_optimizeTrainFromBuffer_cover(
+    void *dictBuffer, size_t dictBufferCapacity, const void *samplesBuffer,
+    const size_t *samplesSizes, unsigned nbSamples,
+    ZDICT_cover_params_t *parameters) {
   /* constants */
   const unsigned nbThreads = parameters->nbThreads;
   const unsigned kMinD = parameters->d == 0 ? 6 : parameters->d;
@@ -947,7 +933,7 @@ ZDICTLIB_API size_t COVER_optimizeTrainFromBuffer(void *dictBuffer,
   const unsigned kIterations =
       (1 + (kMaxD - kMinD) / 2) * (1 + (kMaxK - kMinK) / kStepSize);
   /* Local variables */
-  const int displayLevel = parameters->notificationLevel;
+  const int displayLevel = parameters->zParams.notificationLevel;
   unsigned iteration = 1;
   unsigned d;
   unsigned k;
@@ -976,7 +962,7 @@ ZDICTLIB_API size_t COVER_optimizeTrainFromBuffer(void *dictBuffer,
   /* Initialization */
   COVER_best_init(&best);
   /* Turn down global display level to clean up display at level 2 and below */
-  g_displayLevel = parameters->notificationLevel - 1;
+  g_displayLevel = parameters->zParams.notificationLevel - 1;
   /* Loop through d first because each new value needs a new context */
   LOCALDISPLAYLEVEL(displayLevel, 2, "Trying %u different sets of parameters\n",
                     kIterations);
diff --git a/lib/dictBuilder/zdict.c b/lib/dictBuilder/zdict.c
index 179e02effa4d..742586eacdd2 100644
--- a/lib/dictBuilder/zdict.c
+++ b/lib/dictBuilder/zdict.c
@@ -94,7 +94,7 @@ const char* ZDICT_getErrorName(size_t errorCode) { return ERR_getErrorName(error
 unsigned ZDICT_getDictID(const void* dictBuffer, size_t dictSize)
 {
     if (dictSize < 8) return 0;
-    if (MEM_readLE32(dictBuffer) != ZSTD_DICT_MAGIC) return 0;
+    if (MEM_readLE32(dictBuffer) != ZSTD_MAGIC_DICTIONARY) return 0;
     return MEM_readLE32((const char*)dictBuffer + 4);
 }
 
@@ -487,7 +487,7 @@ static U32 ZDICT_dictSize(const dictItem* dictList)
 }
 
 
-static size_t ZDICT_trainBuffer(dictItem* dictList, U32 dictListSize,
+static size_t ZDICT_trainBuffer_legacy(dictItem* dictList, U32 dictListSize,
                             const void* const buffer, size_t bufferSize,   /* buffer must end with noisy guard band */
                             const size_t* fileSizes, unsigned nbFiles,
                             U32 minRatio, U32 notificationLevel)
@@ -576,7 +576,7 @@ typedef struct
 {
     ZSTD_CCtx* ref;
     ZSTD_CCtx* zc;
-    void* workPlace;   /* must be ZSTD_BLOCKSIZE_ABSOLUTEMAX allocated */
+    void* workPlace;   /* must be ZSTD_BLOCKSIZE_MAX allocated */
 } EStats_ress_t;
 
 #define MAXREPOFFSET 1024
@@ -585,14 +585,14 @@ static void ZDICT_countEStats(EStats_ress_t esr, ZSTD_parameters params,
                             U32* countLit, U32* offsetcodeCount, U32* matchlengthCount, U32* litlengthCount, U32* repOffsets,
                             const void* src, size_t srcSize, U32 notificationLevel)
 {
-    size_t const blockSizeMax = MIN (ZSTD_BLOCKSIZE_ABSOLUTEMAX, 1 << params.cParams.windowLog);
+    size_t const blockSizeMax = MIN (ZSTD_BLOCKSIZE_MAX, 1 << params.cParams.windowLog);
     size_t cSize;
 
     if (srcSize > blockSizeMax) srcSize = blockSizeMax;   /* protection vs large samples */
     {  size_t const errorCode = ZSTD_copyCCtx(esr.zc, esr.ref, 0);
             if (ZSTD_isError(errorCode)) { DISPLAYLEVEL(1, "warning : ZSTD_copyCCtx failed \n"); return; }
     }
-    cSize = ZSTD_compressBlock(esr.zc, esr.workPlace, ZSTD_BLOCKSIZE_ABSOLUTEMAX, src, srcSize);
+    cSize = ZSTD_compressBlock(esr.zc, esr.workPlace, ZSTD_BLOCKSIZE_MAX, src, srcSize);
     if (ZSTD_isError(cSize)) { DISPLAYLEVEL(3, "warning : could not compress sample size %u \n", (U32)srcSize); return; }
 
     if (cSize) {  /* if == 0; block is not compressible */
@@ -634,17 +634,6 @@ static void ZDICT_countEStats(EStats_ress_t esr, ZSTD_parameters params,
     }   }   }
 }
 
-/*
-static size_t ZDICT_maxSampleSize(const size_t* fileSizes, unsigned nbFiles)
-{
-    unsigned u;
-    size_t max=0;
-    for (u=0; u<nbFiles; u++)
-        if (max < fileSizes[u]) max = fileSizes[u];
-    return max;
-}
-*/
-
 static size_t ZDICT_totalSampleSize(const size_t* fileSizes, unsigned nbFiles)
 {
     size_t total=0;
@@ -700,7 +689,7 @@ static size_t ZDICT_analyzeEntropy(void*  dstBuffer, size_t maxDstSize,
     /* init */
     esr.ref = ZSTD_createCCtx();
     esr.zc = ZSTD_createCCtx();
-    esr.workPlace = malloc(ZSTD_BLOCKSIZE_ABSOLUTEMAX);
+    esr.workPlace = malloc(ZSTD_BLOCKSIZE_MAX);
     if (!esr.ref || !esr.zc || !esr.workPlace) {
         eSize = ERROR(memory_allocation);
         DISPLAYLEVEL(1, "Not enough memory \n");
@@ -865,7 +854,7 @@ size_t ZDICT_finalizeDictionary(void* dictBuffer, size_t dictBufferCapacity,
     if (dictBufferCapacity < ZDICT_DICTSIZE_MIN) return ERROR(dstSize_tooSmall);
 
     /* dictionary header */
-    MEM_writeLE32(header, ZSTD_DICT_MAGIC);
+    MEM_writeLE32(header, ZSTD_MAGIC_DICTIONARY);
     {   U64 const randomID = XXH64(customDictContent, dictContentSize, 0);
         U32 const compliantID = (randomID % ((1U<<31)-32768)) + 32768;
         U32 const dictID = params.dictID ? params.dictID : compliantID;
@@ -917,7 +906,7 @@ size_t ZDICT_addEntropyTablesFromBuffer_advanced(void* dictBuffer, size_t dictCo
     }
 
     /* add dictionary header (after entropy tables) */
-    MEM_writeLE32(dictBuffer, ZSTD_DICT_MAGIC);
+    MEM_writeLE32(dictBuffer, ZSTD_MAGIC_DICTIONARY);
     {   U64 const randomID = XXH64((char*)dictBuffer + dictBufferCapacity - dictContentSize, dictContentSize, 0);
         U32 const compliantID = (randomID % ((1U<<31)-32768)) + 32768;
         U32 const dictID = params.dictID ? params.dictID : compliantID;
@@ -930,14 +919,14 @@ size_t ZDICT_addEntropyTablesFromBuffer_advanced(void* dictBuffer, size_t dictCo
 }
 
 
-/*! ZDICT_trainFromBuffer_unsafe() :
+/*! ZDICT_trainFromBuffer_unsafe_legacy() :
 *   Warning : `samplesBuffer` must be followed by noisy guard band.
 *   @return : size of dictionary, or an error code which can be tested with ZDICT_isError()
 */
-size_t ZDICT_trainFromBuffer_unsafe(
+size_t ZDICT_trainFromBuffer_unsafe_legacy(
                             void* dictBuffer, size_t maxDictSize,
                             const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
-                            ZDICT_params_t params)
+                            ZDICT_legacy_params_t params)
 {
     U32 const dictListSize = MAX(MAX(DICTLISTSIZE_DEFAULT, nbSamples), (U32)(maxDictSize/16));
     dictItem* const dictList = (dictItem*)malloc(dictListSize * sizeof(*dictList));
@@ -946,7 +935,7 @@ size_t ZDICT_trainFromBuffer_unsafe(
     size_t const targetDictSize = maxDictSize;
     size_t const samplesBuffSize = ZDICT_totalSampleSize(samplesSizes, nbSamples);
     size_t dictSize = 0;
-    U32 const notificationLevel = params.notificationLevel;
+    U32 const notificationLevel = params.zParams.notificationLevel;
 
     /* checks */
     if (!dictList) return ERROR(memory_allocation);
@@ -957,13 +946,13 @@ size_t ZDICT_trainFromBuffer_unsafe(
     ZDICT_initDictItem(dictList);
 
     /* build dictionary */
-    ZDICT_trainBuffer(dictList, dictListSize,
-                    samplesBuffer, samplesBuffSize,
-                    samplesSizes, nbSamples,
-                    minRep, notificationLevel);
+    ZDICT_trainBuffer_legacy(dictList, dictListSize,
+                       samplesBuffer, samplesBuffSize,
+                       samplesSizes, nbSamples,
+                       minRep, notificationLevel);
 
     /* display best matches */
-    if (params.notificationLevel>= 3) {
+    if (params.zParams.notificationLevel>= 3) {
         U32 const nb = MIN(25, dictList[0].pos);
         U32 const dictContentSize = ZDICT_dictSize(dictList);
         U32 u;
@@ -1026,7 +1015,7 @@ size_t ZDICT_trainFromBuffer_unsafe(
 
         dictSize = ZDICT_addEntropyTablesFromBuffer_advanced(dictBuffer, dictContentSize, maxDictSize,
                                                              samplesBuffer, samplesSizes, nbSamples,
-                                                             params);
+                                                             params.zParams);
     }
 
     /* clean up */
@@ -1037,9 +1026,9 @@ size_t ZDICT_trainFromBuffer_unsafe(
 
 /* issue : samplesBuffer need to be followed by a noisy guard band.
 *  work around : duplicate the buffer, and add the noise */
-size_t ZDICT_trainFromBuffer_advanced(void* dictBuffer, size_t dictBufferCapacity,
-                                      const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
-                                      ZDICT_params_t params)
+size_t ZDICT_trainFromBuffer_legacy(void* dictBuffer, size_t dictBufferCapacity,
+                              const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
+                              ZDICT_legacy_params_t params)
 {
     size_t result;
     void* newBuff;
@@ -1052,10 +1041,9 @@ size_t ZDICT_trainFromBuffer_advanced(void* dictBuffer, size_t dictBufferCapacit
     memcpy(newBuff, samplesBuffer, sBuffSize);
     ZDICT_fillNoise((char*)newBuff + sBuffSize, NOISELENGTH);   /* guard band, for end of buffer condition */
 
-    result = ZDICT_trainFromBuffer_unsafe(
-                                        dictBuffer, dictBufferCapacity,
-                                        newBuff, samplesSizes, nbSamples,
-                                        params);
+    result =
+        ZDICT_trainFromBuffer_unsafe_legacy(dictBuffer, dictBufferCapacity, newBuff,
+                                            samplesSizes, nbSamples, params);
     free(newBuff);
     return result;
 }
@@ -1064,11 +1052,13 @@ size_t ZDICT_trainFromBuffer_advanced(void* dictBuffer, size_t dictBufferCapacit
 size_t ZDICT_trainFromBuffer(void* dictBuffer, size_t dictBufferCapacity,
                              const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples)
 {
-    ZDICT_params_t params;
+    ZDICT_cover_params_t params;
     memset(&params, 0, sizeof(params));
-    return ZDICT_trainFromBuffer_advanced(dictBuffer, dictBufferCapacity,
-                                          samplesBuffer, samplesSizes, nbSamples,
-                                          params);
+    params.d = 8;
+    params.steps = 4;
+    return ZDICT_optimizeTrainFromBuffer_cover(dictBuffer, dictBufferCapacity,
+                                               samplesBuffer, samplesSizes,
+                                               nbSamples, &params);
 }
 
 size_t ZDICT_addEntropyTablesFromBuffer(void* dictBuffer, size_t dictContentSize, size_t dictBufferCapacity,
diff --git a/lib/dictBuilder/zdict.h b/lib/dictBuilder/zdict.h
index 9b53de346527..7bfbb351a1dd 100644
--- a/lib/dictBuilder/zdict.h
+++ b/lib/dictBuilder/zdict.h
@@ -20,10 +20,12 @@ extern "C" {
 
 
 /* =====   ZDICTLIB_API : control library symbols visibility   ===== */
-#if defined(__GNUC__) && (__GNUC__ >= 4)
-#  define ZDICTLIB_VISIBILITY __attribute__ ((visibility ("default")))
-#else
-#  define ZDICTLIB_VISIBILITY
+#ifndef ZDICTLIB_VISIBILITY
+#  if defined(__GNUC__) && (__GNUC__ >= 4)
+#    define ZDICTLIB_VISIBILITY __attribute__ ((visibility ("default")))
+#  else
+#    define ZDICTLIB_VISIBILITY
+#  endif
 #endif
 #if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1)
 #  define ZDICTLIB_API __declspec(dllexport) ZDICTLIB_VISIBILITY
@@ -34,18 +36,20 @@ extern "C" {
 #endif
 
 
-/*! ZDICT_trainFromBuffer() :
-    Train a dictionary from an array of samples.
-    Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
-    supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
-    The resulting dictionary will be saved into `dictBuffer`.
-    @return : size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
-              or an error code, which can be tested with ZDICT_isError().
-    Tips : In general, a reasonable dictionary has a size of ~ 100 KB.
-           It's obviously possible to target smaller or larger ones, just by specifying different `dictBufferCapacity`.
-           In general, it's recommended to provide a few thousands samples, but this can vary a lot.
-           It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
-*/
+/*! ZDICT_trainFromBuffer():
+ * Train a dictionary from an array of samples.
+ * Uses ZDICT_optimizeTrainFromBuffer_cover() single-threaded, with d=8 and steps=4.
+ * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
+ * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
+ * The resulting dictionary will be saved into `dictBuffer`.
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
+ *           or an error code, which can be tested with ZDICT_isError().
+ * Note: ZDICT_trainFromBuffer() requires about 9 bytes of memory for each input byte.
+ * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
+ *        It's obviously possible to target smaller or larger ones, just by specifying different `dictBufferCapacity`.
+ *        In general, it's recommended to provide a few thousands samples, but this can vary a lot.
+ *        It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
+ */
 ZDICTLIB_API size_t ZDICT_trainFromBuffer(void* dictBuffer, size_t dictBufferCapacity,
                        const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples);
 
@@ -67,94 +71,78 @@ ZDICTLIB_API const char* ZDICT_getErrorName(size_t errorCode);
  * ==================================================================================== */
 
 typedef struct {
-    unsigned selectivityLevel;   /* 0 means default; larger => select more => larger dictionary */
     int      compressionLevel;   /* 0 means default; target a specific zstd compression level */
     unsigned notificationLevel;  /* Write to stderr; 0 = none (default); 1 = errors; 2 = progression; 3 = details; 4 = debug; */
     unsigned dictID;             /* 0 means auto mode (32-bits random value); other : force dictID value */
-    unsigned reserved[2];        /* reserved space for future parameters */
 } ZDICT_params_t;
 
-
-/*! ZDICT_trainFromBuffer_advanced() :
-    Same as ZDICT_trainFromBuffer() with control over more parameters.
-    `parameters` is optional and can be provided with values set to 0 to mean "default".
-    @return : size of dictionary stored into `dictBuffer` (<= `dictBufferSize`),
-              or an error code, which can be tested by ZDICT_isError().
-    note : ZDICT_trainFromBuffer_advanced() will send notifications into stderr if instructed to, using notificationLevel>0.
-*/
-ZDICTLIB_API size_t ZDICT_trainFromBuffer_advanced(void* dictBuffer, size_t dictBufferCapacity,
-                                const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
-                                ZDICT_params_t parameters);
-
-/*! COVER_params_t :
-    For all values 0 means default.
-    k and d are the only required parameters.
-*/
+/*! ZDICT_cover_params_t:
+ *  For all values 0 means default.
+ *  k and d are the only required parameters.
+ */
 typedef struct {
     unsigned k;                  /* Segment size : constraint: 0 < k : Reasonable range [16, 2048+] */
     unsigned d;                  /* dmer size : constraint: 0 < d <= k : Reasonable range [6, 16] */
     unsigned steps;              /* Number of steps : Only used for optimization : 0 means default (32) : Higher means more parameters checked */
-
     unsigned nbThreads;          /* Number of threads : constraint: 0 < nbThreads : 1 means single-threaded : Only used for optimization : Ignored if ZSTD_MULTITHREAD is not defined */
-    unsigned notificationLevel;  /* Write to stderr; 0 = none (default); 1 = errors; 2 = progression; 3 = details; 4 = debug; */
-    unsigned dictID;             /* 0 means auto mode (32-bits random value); other : force dictID value */
-    int      compressionLevel;   /* 0 means default; target a specific zstd compression level */
-} COVER_params_t;
-
-
-/*! COVER_trainFromBuffer() :
-    Train a dictionary from an array of samples using the COVER algorithm.
-    Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
-    supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
-    The resulting dictionary will be saved into `dictBuffer`.
-    @return : size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
-              or an error code, which can be tested with ZDICT_isError().
-    Note : COVER_trainFromBuffer() requires about 9 bytes of memory for each input byte.
-    Tips : In general, a reasonable dictionary has a size of ~ 100 KB.
-           It's obviously possible to target smaller or larger ones, just by specifying different `dictBufferCapacity`.
-           In general, it's recommended to provide a few thousands samples, but this can vary a lot.
-           It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
-*/
-ZDICTLIB_API size_t COVER_trainFromBuffer(void* dictBuffer, size_t dictBufferCapacity,
-                              const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
-                              COVER_params_t parameters);
-
-/*! COVER_optimizeTrainFromBuffer() :
-    The same requirements as above hold for all the parameters except `parameters`.
-    This function tries many parameter combinations and picks the best parameters.
-    `*parameters` is filled with the best parameters found, and the dictionary
-    constructed with those parameters is stored in `dictBuffer`.
-
-    All of the parameters d, k, steps are optional.
-    If d is non-zero then we don't check multiple values of d, otherwise we check d = {6, 8, 10, 12, 14, 16}.
-    if steps is zero it defaults to its default value.
-    If k is non-zero then we don't check multiple values of k, otherwise we check steps values in [16, 2048].
-
-    @return : size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
-              or an error code, which can be tested with ZDICT_isError().
-              On success `*parameters` contains the parameters selected.
-    Note : COVER_optimizeTrainFromBuffer() requires about 8 bytes of memory for each input byte and additionally another 5 bytes of memory for each byte of memory for each thread.
-*/
-ZDICTLIB_API size_t COVER_optimizeTrainFromBuffer(void* dictBuffer, size_t dictBufferCapacity,
-                                     const void* samplesBuffer, const size_t *samplesSizes, unsigned nbSamples,
-                                     COVER_params_t *parameters);
-
-/*! ZDICT_finalizeDictionary() :
-
-    Given a custom content as a basis for dictionary, and a set of samples,
-    finalize dictionary by adding headers and statistics.
-
-    Samples must be stored concatenated in a flat buffer `samplesBuffer`,
-    supplied with an array of sizes `samplesSizes`, providing the size of each sample in order.
-
-    dictContentSize must be >= ZDICT_CONTENTSIZE_MIN bytes.
-    maxDictSize must be >= dictContentSize, and must be >= ZDICT_DICTSIZE_MIN bytes.
-
-    @return : size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`),
-              or an error code, which can be tested by ZDICT_isError().
-    note : ZDICT_finalizeDictionary() will push notifications into stderr if instructed to, using notificationLevel>0.
-    note 2 : dictBuffer and dictContent can overlap
-*/
+    ZDICT_params_t zParams;
+} ZDICT_cover_params_t;
+
+
+/*! ZDICT_trainFromBuffer_cover():
+ * Train a dictionary from an array of samples using the COVER algorithm.
+ * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
+ * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
+ * The resulting dictionary will be saved into `dictBuffer`.
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
+ *           or an error code, which can be tested with ZDICT_isError().
+ * Note: ZDICT_trainFromBuffer_cover() requires about 9 bytes of memory for each input byte.
+ * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
+ *        It's obviously possible to target smaller or larger ones, just by specifying different `dictBufferCapacity`.
+ *        In general, it's recommended to provide a few thousands samples, but this can vary a lot.
+ *        It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
+ */
+ZDICTLIB_API size_t ZDICT_trainFromBuffer_cover(
+    void *dictBuffer, size_t dictBufferCapacity, const void *samplesBuffer,
+    const size_t *samplesSizes, unsigned nbSamples,
+    ZDICT_cover_params_t parameters);
+
+/*! ZDICT_optimizeTrainFromBuffer_cover():
+ * The same requirements as above hold for all the parameters except `parameters`.
+ * This function tries many parameter combinations and picks the best parameters.
+ * `*parameters` is filled with the best parameters found, and the dictionary
+ * constructed with those parameters is stored in `dictBuffer`.
+ *
+ * All of the parameters d, k, steps are optional.
+ * If d is non-zero then we don't check multiple values of d, otherwise we check d = {6, 8, 10, 12, 14, 16}.
+ * if steps is zero it defaults to its default value.
+ * If k is non-zero then we don't check multiple values of k, otherwise we check steps values in [16, 2048].
+ *
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
+ *           or an error code, which can be tested with ZDICT_isError().
+ *           On success `*parameters` contains the parameters selected.
+ * Note: ZDICT_optimizeTrainFromBuffer_cover() requires about 8 bytes of memory for each input byte and additionally another 5 bytes of memory for each byte of memory for each thread.
+ */
+ZDICTLIB_API size_t ZDICT_optimizeTrainFromBuffer_cover(
+    void *dictBuffer, size_t dictBufferCapacity, const void *samplesBuffer,
+    const size_t *samplesSizes, unsigned nbSamples,
+    ZDICT_cover_params_t *parameters);
+
+/*! ZDICT_finalizeDictionary():
+ * Given a custom content as a basis for dictionary, and a set of samples,
+ * finalize dictionary by adding headers and statistics.
+ *
+ * Samples must be stored concatenated in a flat buffer `samplesBuffer`,
+ * supplied with an array of sizes `samplesSizes`, providing the size of each sample in order.
+ *
+ * dictContentSize must be >= ZDICT_CONTENTSIZE_MIN bytes.
+ * maxDictSize must be >= dictContentSize, and must be >= ZDICT_DICTSIZE_MIN bytes.
+ *
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`),
+ *           or an error code, which can be tested by ZDICT_isError().
+ * Note: ZDICT_finalizeDictionary() will push notifications into stderr if instructed to, using notificationLevel>0.
+ * Note 2: dictBuffer and dictContent can overlap
+ */
 #define ZDICT_CONTENTSIZE_MIN 128
 #define ZDICT_DICTSIZE_MIN    256
 ZDICTLIB_API size_t ZDICT_finalizeDictionary(void* dictBuffer, size_t dictBufferCapacity,
@@ -162,7 +150,28 @@ ZDICTLIB_API size_t ZDICT_finalizeDictionary(void* dictBuffer, size_t dictBuffer
                                 const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
                                 ZDICT_params_t parameters);
 
-
+typedef struct {
+    unsigned selectivityLevel;   /* 0 means default; larger => select more => larger dictionary */
+    ZDICT_params_t zParams;
+} ZDICT_legacy_params_t;
+
+/*! ZDICT_trainFromBuffer_legacy():
+ * Train a dictionary from an array of samples.
+ * Samples must be stored concatenated in a single flat buffer `samplesBuffer`,
+ * supplied with an array of sizes `samplesSizes`, providing the size of each sample, in order.
+ * The resulting dictionary will be saved into `dictBuffer`.
+ * `parameters` is optional and can be provided with values set to 0 to mean "default".
+ * @return: size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
+ *           or an error code, which can be tested with ZDICT_isError().
+ * Tips: In general, a reasonable dictionary has a size of ~ 100 KB.
+ *        It's obviously possible to target smaller or larger ones, just by specifying different `dictBufferCapacity`.
+ *        In general, it's recommended to provide a few thousands samples, but this can vary a lot.
+ *        It's recommended that total size of all samples be about ~x100 times the target size of dictionary.
+ * Note: ZDICT_trainFromBuffer_legacy() will send notifications into stderr if instructed to, using notificationLevel>0.
+ */
+ZDICTLIB_API size_t ZDICT_trainFromBuffer_legacy(
+    void *dictBuffer, size_t dictBufferCapacity, const void *samplesBuffer,
+    const size_t *samplesSizes, unsigned nbSamples, ZDICT_legacy_params_t parameters);
 
 /* Deprecation warnings */
 /* It is generally possible to disable deprecation warnings from compiler,
diff --git a/lib/legacy/zstd_v04.c b/lib/legacy/zstd_v04.c
index 1a29da92d1e8..8b8e23cb09cb 100644
--- a/lib/legacy/zstd_v04.c
+++ b/lib/legacy/zstd_v04.c
@@ -816,13 +816,13 @@ MEM_STATIC size_t BIT_initDStream(BIT_DStream_t* bitD, const void* srcBuffer, si
         bitD->bitContainer = *(const BYTE*)(bitD->start);
         switch(srcSize)
         {
-            case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16);
-            case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24);
-            case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32);
-            case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24;
-            case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16;
-            case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) <<  8;
-            default:;
+            case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16);/* fall-through */
+            case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24);/* fall-through */
+            case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32);/* fall-through */
+            case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24; /* fall-through */
+            case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16; /* fall-through */
+            case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) <<  8; /* fall-through */
+            default: break;
         }
         contain32 = ((const BYTE*)srcBuffer)[srcSize-1];
         if (contain32 == 0) return ERROR(GENERIC);   /* endMark not present */
@@ -3665,7 +3665,7 @@ static size_t ZBUFF_decompressContinue(ZBUFF_DCtx* zbc, void* dst, size_t* maxDs
                     break;
                 }
                 zbc->stage = ZBUFFds_read;
-
+		/* fall-through */
         case ZBUFFds_read:
             {
                 size_t neededInSize = ZSTD_nextSrcSizeToDecompress(zbc->zc);
@@ -3691,7 +3691,7 @@ static size_t ZBUFF_decompressContinue(ZBUFF_DCtx* zbc, void* dst, size_t* maxDs
                 if (ip==iend) { notDone = 0; break; }   /* no more input */
                 zbc->stage = ZBUFFds_load;
             }
-
+	    /* fall-through */
         case ZBUFFds_load:
             {
                 size_t neededInSize = ZSTD_nextSrcSizeToDecompress(zbc->zc);
@@ -3711,9 +3711,10 @@ static size_t ZBUFF_decompressContinue(ZBUFF_DCtx* zbc, void* dst, size_t* maxDs
                     if (!decodedSize) { zbc->stage = ZBUFFds_read; break; }   /* this was just a header */
                     zbc->outEnd = zbc->outStart +  decodedSize;
                     zbc->stage = ZBUFFds_flush;
-                    // break; /* ZBUFFds_flush follows */
+                    /* ZBUFFds_flush follows */
                 }
             }
+	    /* fall-through */
         case ZBUFFds_flush:
             {
                 size_t toFlushSize = zbc->outEnd - zbc->outStart;
diff --git a/lib/legacy/zstd_v05.c b/lib/legacy/zstd_v05.c
index 674f5b0e4a8e..e929618a3bf5 100644
--- a/lib/legacy/zstd_v05.c
+++ b/lib/legacy/zstd_v05.c
@@ -326,13 +326,6 @@ size_t ZSTDv05_decompress_usingPreparedDCtx(
 *  Streaming functions (direct mode)
 ****************************************/
 size_t ZSTDv05_decompressBegin(ZSTDv05_DCtx* dctx);
-size_t ZSTDv05_decompressBegin_usingDict(ZSTDv05_DCtx* dctx, const void* dict, size_t dictSize);
-void   ZSTDv05_copyDCtx(ZSTDv05_DCtx* dctx, const ZSTDv05_DCtx* preparedDCtx);
-
-size_t ZSTDv05_getFrameParams(ZSTDv05_parameters* params, const void* src, size_t srcSize);
-
-size_t ZSTDv05_nextSrcSizeToDecompress(ZSTDv05_DCtx* dctx);
-size_t ZSTDv05_decompressContinue(ZSTDv05_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 
 /*
   Streaming decompression, direct mode (bufferless)
@@ -818,13 +811,13 @@ MEM_STATIC size_t BITv05_initDStream(BITv05_DStream_t* bitD, const void* srcBuff
         bitD->bitContainer = *(const BYTE*)(bitD->start);
         switch(srcSize)
         {
-            case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16);
-            case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24);
-            case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32);
-            case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24;
-            case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16;
-            case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) <<  8;
-            default:;
+            case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16);/* fall-through */
+            case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24);/* fall-through */
+            case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32);/* fall-through */
+            case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24; /* fall-through */
+            case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16; /* fall-through */
+            case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) <<  8; /* fall-through */
+            default: break;
         }
         contain32 = ((const BYTE*)srcBuffer)[srcSize-1];
         if (contain32 == 0) return ERROR(GENERIC);   /* endMark not present */
@@ -3955,7 +3948,7 @@ size_t ZBUFFv05_decompressContinue(ZBUFFv05_DCtx* zbc, void* dst, size_t* maxDst
                 zbc->stage = ZBUFFv05ds_decodeHeader;
                 break;
             }
-
+	    /* fall-through */
         case ZBUFFv05ds_loadHeader:
             /* complete header from src */
             {
@@ -3973,7 +3966,7 @@ size_t ZBUFFv05_decompressContinue(ZBUFFv05_DCtx* zbc, void* dst, size_t* maxDst
                 }
                 // zbc->stage = ZBUFFv05ds_decodeHeader; break;   /* useless : stage follows */
             }
-
+	    /* fall-through */
         case ZBUFFv05ds_decodeHeader:
                 /* apply header to create / resize buffers */
                 {
@@ -4000,7 +3993,7 @@ size_t ZBUFFv05_decompressContinue(ZBUFFv05_DCtx* zbc, void* dst, size_t* maxDst
                     break;
                 }
                 zbc->stage = ZBUFFv05ds_read;
-
+		/* fall-through */
         case ZBUFFv05ds_read:
             {
                 size_t neededInSize = ZSTDv05_nextSrcSizeToDecompress(zbc->zc);
@@ -4024,7 +4017,7 @@ size_t ZBUFFv05_decompressContinue(ZBUFFv05_DCtx* zbc, void* dst, size_t* maxDst
                 if (ip==iend) { notDone = 0; break; }   /* no more input */
                 zbc->stage = ZBUFFv05ds_load;
             }
-
+	    /* fall-through */
         case ZBUFFv05ds_load:
             {
                 size_t neededInSize = ZSTDv05_nextSrcSizeToDecompress(zbc->zc);
@@ -4045,7 +4038,9 @@ size_t ZBUFFv05_decompressContinue(ZBUFFv05_DCtx* zbc, void* dst, size_t* maxDst
                     zbc->outEnd = zbc->outStart +  decodedSize;
                     zbc->stage = ZBUFFv05ds_flush;
                     // break; /* ZBUFFv05ds_flush follows */
-            }   }
+                }
+	    }
+	    /* fall-through */
         case ZBUFFv05ds_flush:
             {
                 size_t toFlushSize = zbc->outEnd - zbc->outStart;
diff --git a/lib/legacy/zstd_v06.c b/lib/legacy/zstd_v06.c
index ad8c4cd3186d..26f0929da6fd 100644
--- a/lib/legacy/zstd_v06.c
+++ b/lib/legacy/zstd_v06.c
@@ -910,13 +910,13 @@ MEM_STATIC size_t BITv06_initDStream(BITv06_DStream_t* bitD, const void* srcBuff
         bitD->bitContainer = *(const BYTE*)(bitD->start);
         switch(srcSize)
         {
-            case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);
-            case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);
-            case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);
-            case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24;
-            case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16;
-            case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) <<  8;
-            default:;
+            case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);/* fall-through */
+            case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);/* fall-through */
+            case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);/* fall-through */
+            case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24; /* fall-through */
+            case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16; /* fall-through */
+            case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) <<  8; /* fall-through */
+            default: break;
         }
         { BYTE const lastByte = ((const BYTE*)srcBuffer)[srcSize-1];
           if (lastByte == 0) return ERROR(GENERIC);   /* endMark not present */
@@ -3789,7 +3789,7 @@ size_t ZSTDv06_decompressContinue(ZSTDv06_DCtx* dctx, void* dst, size_t dstCapac
             return 0;
         }
         dctx->expected = 0;   /* not necessary to copy more */
-
+	/* fall-through */
     case ZSTDds_decodeFrameHeader:
         {   size_t result;
             memcpy(dctx->headerBuffer + ZSTDv06_frameHeaderSize_min, src, dctx->expected);
@@ -4116,7 +4116,7 @@ size_t ZBUFFv06_decompressContinue(ZBUFFv06_DCtx* zbd,
                         if (zbd->outBuff == NULL) return ERROR(memory_allocation);
             }   }   }
             zbd->stage = ZBUFFds_read;
-
+	    /* fall-through */
         case ZBUFFds_read:
             {   size_t const neededInSize = ZSTDv06_nextSrcSizeToDecompress(zbd->zd);
                 if (neededInSize==0) {  /* end of frame */
@@ -4138,7 +4138,7 @@ size_t ZBUFFv06_decompressContinue(ZBUFFv06_DCtx* zbd,
                 if (ip==iend) { notDone = 0; break; }   /* no more input */
                 zbd->stage = ZBUFFds_load;
             }
-
+	    /* fall-through */
         case ZBUFFds_load:
             {   size_t const neededInSize = ZSTDv06_nextSrcSizeToDecompress(zbd->zd);
                 size_t const toLoad = neededInSize - zbd->inPos;   /* should always be <= remaining space within inBuff */
@@ -4159,8 +4159,9 @@ size_t ZBUFFv06_decompressContinue(ZBUFFv06_DCtx* zbd,
                     zbd->outEnd = zbd->outStart +  decodedSize;
                     zbd->stage = ZBUFFds_flush;
                     // break; /* ZBUFFds_flush follows */
-            }   }
-
+                }
+	    }
+	    /* fall-through */
         case ZBUFFds_flush:
             {   size_t const toFlushSize = zbd->outEnd - zbd->outStart;
                 size_t const flushedSize = ZBUFFv06_limitCopy(op, oend-op, zbd->outBuff + zbd->outStart, toFlushSize);
diff --git a/lib/legacy/zstd_v07.c b/lib/legacy/zstd_v07.c
index a54ad0ffdba9..6669b71cea40 100644
--- a/lib/legacy/zstd_v07.c
+++ b/lib/legacy/zstd_v07.c
@@ -580,13 +580,13 @@ MEM_STATIC size_t BITv07_initDStream(BITv07_DStream_t* bitD, const void* srcBuff
         bitD->bitContainer = *(const BYTE*)(bitD->start);
         switch(srcSize)
         {
-            case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);
-            case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);
-            case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);
-            case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24;
-            case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16;
-            case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) <<  8;
-            default:;
+            case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);/* fall-through */
+            case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);/* fall-through */
+            case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);/* fall-through */
+            case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24; /* fall-through */
+            case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16; /* fall-through */
+            case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) <<  8; /* fall-through */
+            default: break;
         }
         { BYTE const lastByte = ((const BYTE*)srcBuffer)[srcSize-1];
           bitD->bitsConsumed = lastByte ? 8 - BITv07_highbit32(lastByte) : 0;
@@ -2920,8 +2920,6 @@ typedef struct {
 void ZSTDv07_seqToCodes(const seqStore_t* seqStorePtr, size_t const nbSeq);
 
 /* custom memory allocation functions */
-void* ZSTDv07_defaultAllocFunction(void* opaque, size_t size);
-void ZSTDv07_defaultFreeFunction(void* opaque, void* address);
 static const ZSTDv07_customMem defaultCustomMem = { ZSTDv07_defaultAllocFunction, ZSTDv07_defaultFreeFunction, NULL };
 
 #endif   /* ZSTDv07_CCOMMON_H_MODULE */
@@ -4047,7 +4045,7 @@ size_t ZSTDv07_decompressContinue(ZSTDv07_DCtx* dctx, void* dst, size_t dstCapac
             return 0;
         }
         dctx->expected = 0;   /* not necessary to copy more */
-
+	/* fall-through */
     case ZSTDds_decodeFrameHeader:
         {   size_t result;
             memcpy(dctx->headerBuffer + ZSTDv07_frameHeaderSize_min, src, dctx->expected);
@@ -4494,7 +4492,7 @@ size_t ZBUFFv07_decompressContinue(ZBUFFv07_DCtx* zbd,
             }   }   }
             zbd->stage = ZBUFFds_read;
             /* pass-through */
-
+	    /* fall-through */
         case ZBUFFds_read:
             {   size_t const neededInSize = ZSTDv07_nextSrcSizeToDecompress(zbd->zd);
                 if (neededInSize==0) {  /* end of frame */
@@ -4517,7 +4515,7 @@ size_t ZBUFFv07_decompressContinue(ZBUFFv07_DCtx* zbd,
                 if (ip==iend) { notDone = 0; break; }   /* no more input */
                 zbd->stage = ZBUFFds_load;
             }
-
+	    /* fall-through */
         case ZBUFFds_load:
             {   size_t const neededInSize = ZSTDv07_nextSrcSizeToDecompress(zbd->zd);
                 size_t const toLoad = neededInSize - zbd->inPos;   /* should always be <= remaining space within inBuff */
@@ -4540,8 +4538,9 @@ size_t ZBUFFv07_decompressContinue(ZBUFFv07_DCtx* zbd,
                     zbd->stage = ZBUFFds_flush;
                     /* break; */
                     /* pass-through */
-            }   }
-
+                }
+	    }
+	    /* fall-through */
         case ZBUFFds_flush:
             {   size_t const toFlushSize = zbd->outEnd - zbd->outStart;
                 size_t const flushedSize = ZBUFFv07_limitCopy(op, oend-op, zbd->outBuff + zbd->outStart, toFlushSize);
diff --git a/lib/zstd.h b/lib/zstd.h
index f8050c136104..58e9a5606db8 100644
--- a/lib/zstd.h
+++ b/lib/zstd.h
@@ -19,10 +19,12 @@ extern "C" {
 
 
 /* =====   ZSTDLIB_API : control library symbols visibility   ===== */
-#if defined(__GNUC__) && (__GNUC__ >= 4)
-#  define ZSTDLIB_VISIBILITY __attribute__ ((visibility ("default")))
-#else
-#  define ZSTDLIB_VISIBILITY
+#ifndef ZSTDLIB_VISIBILITY
+#  if defined(__GNUC__) && (__GNUC__ >= 4)
+#    define ZSTDLIB_VISIBILITY __attribute__ ((visibility ("default")))
+#  else
+#    define ZSTDLIB_VISIBILITY
+#  endif
 #endif
 #if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1)
 #  define ZSTDLIB_API __declspec(dllexport) ZSTDLIB_VISIBILITY
@@ -36,35 +38,37 @@ extern "C" {
 /*******************************************************************************************************
   Introduction
 
-  zstd, short for Zstandard, is a fast lossless compression algorithm, targeting real-time compression scenarios
-  at zlib-level and better compression ratios. The zstd compression library provides in-memory compression and
-  decompression functions. The library supports compression levels from 1 up to ZSTD_maxCLevel() which is 22.
+  zstd, short for Zstandard, is a fast lossless compression algorithm,
+  targeting real-time compression scenarios at zlib-level and better compression ratios.
+  The zstd compression library provides in-memory compression and decompression functions.
+  The library supports compression levels from 1 up to ZSTD_maxCLevel() which is currently 22.
   Levels >= 20, labeled `--ultra`, should be used with caution, as they require more memory.
   Compression can be done in:
     - a single step (described as Simple API)
     - a single step, reusing a context (described as Explicit memory management)
     - unbounded multiple steps (described as Streaming compression)
-  The compression ratio achievable on small data can be highly improved using compression with a dictionary in:
+  The compression ratio achievable on small data can be highly improved using a dictionary in:
     - a single step (described as Simple dictionary API)
     - a single step, reusing a dictionary (described as Fast dictionary API)
 
   Advanced experimental functions can be accessed using #define ZSTD_STATIC_LINKING_ONLY before including zstd.h.
-  These APIs shall never be used with a dynamic library.
+  Advanced experimental APIs shall never be used with a dynamic library.
   They are not "stable", their definition may change in the future. Only static linking is allowed.
 *********************************************************************************************************/
 
 /*------   Version   ------*/
 #define ZSTD_VERSION_MAJOR    1
-#define ZSTD_VERSION_MINOR    2
+#define ZSTD_VERSION_MINOR    3
 #define ZSTD_VERSION_RELEASE  0
 
+#define ZSTD_VERSION_NUMBER  (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE)
+ZSTDLIB_API unsigned ZSTD_versionNumber(void);   /**< useful to check dll version */
+
 #define ZSTD_LIB_VERSION ZSTD_VERSION_MAJOR.ZSTD_VERSION_MINOR.ZSTD_VERSION_RELEASE
 #define ZSTD_QUOTE(str) #str
 #define ZSTD_EXPAND_AND_QUOTE(str) ZSTD_QUOTE(str)
 #define ZSTD_VERSION_STRING ZSTD_EXPAND_AND_QUOTE(ZSTD_LIB_VERSION)
-
-#define ZSTD_VERSION_NUMBER  (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE)
-ZSTDLIB_API unsigned ZSTD_versionNumber(void);   /**< library version number; to be used when checking dll version */
+ZSTDLIB_API const char* ZSTD_versionString(void);   /* v1.3.0 */
 
 
 /***************************************
@@ -81,38 +85,48 @@ ZSTDLIB_API size_t ZSTD_compress( void* dst, size_t dstCapacity,
 
 /*! ZSTD_decompress() :
  *  `compressedSize` : must be the _exact_ size of some number of compressed and/or skippable frames.
- *  `dstCapacity` is an upper bound of originalSize.
+ *  `dstCapacity` is an upper bound of originalSize to regenerate.
  *  If user cannot imply a maximum upper bound, it's better to use streaming mode to decompress data.
  *  @return : the number of bytes decompressed into `dst` (<= `dstCapacity`),
  *            or an errorCode if it fails (which can be tested using ZSTD_isError()). */
 ZSTDLIB_API size_t ZSTD_decompress( void* dst, size_t dstCapacity,
                               const void* src, size_t compressedSize);
 
-/*! ZSTD_getDecompressedSize() :
- *  NOTE: This function is planned to be obsolete, in favour of ZSTD_getFrameContentSize.
- *  ZSTD_getFrameContentSize functions the same way, returning the decompressed size of a single
- *  frame, but distinguishes empty frames from frames with an unknown size, or errors.
- *
- *  Additionally, ZSTD_findDecompressedSize can be used instead.  It can handle multiple
- *  concatenated frames in one buffer, and so is more general.
- *  As a result however, it requires more computation and entire frames to be passed to it,
- *  as opposed to ZSTD_getFrameContentSize which requires only a single frame's header.
- *
- *  'src' is the start of a zstd compressed frame.
- *  @return : content size to be decompressed, as a 64-bits value _if known_, 0 otherwise.
- *   note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
- *            When `return==0`, data to decompress could be any size.
+/*! ZSTD_getFrameContentSize() : v1.3.0
+ *  `src` should point to the start of a ZSTD encoded frame.
+ *  `srcSize` must be at least as large as the frame header.
+ *            hint : any size >= `ZSTD_frameHeaderSize_max` is large enough.
+ *  @return : - decompressed size of the frame in `src`, if known
+ *            - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined
+ *            - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small)
+ *   note 1 : a 0 return value means the frame is valid but "empty".
+ *   note 2 : decompressed size is an optional field, it may not be present, typically in streaming mode.
+ *            When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size.
  *            In which case, it's necessary to use streaming mode to decompress data.
- *            Optionally, application can still use ZSTD_decompress() while relying on implied limits.
- *            (For example, data may be necessarily cut into blocks <= 16 KB).
- *   note 2 : decompressed size is always present when compression is done with ZSTD_compress()
- *   note 3 : decompressed size can be very large (64-bits value),
+ *            Optionally, application can rely on some implicit limit,
+ *            as ZSTD_decompress() only needs an upper bound of decompressed size.
+ *            (For example, data could be necessarily cut into blocks <= 16 KB).
+ *   note 3 : decompressed size is always present when compression is done with ZSTD_compress()
+ *   note 4 : decompressed size can be very large (64-bits value),
  *            potentially larger than what local system can handle as a single memory segment.
  *            In which case, it's necessary to use streaming mode to decompress data.
- *   note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
- *            Always ensure result fits within application's authorized limits.
+ *   note 5 : If source is untrusted, decompressed size could be wrong or intentionally modified.
+ *            Always ensure return value fits within application's authorized limits.
  *            Each application can set its own limits.
- *   note 5 : when `return==0`, if precise failure cause is needed, use ZSTD_getFrameParams() to know more. */
+ *   note 6 : This function replaces ZSTD_getDecompressedSize() */
+#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1)
+#define ZSTD_CONTENTSIZE_ERROR   (0ULL - 2)
+ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
+
+/*! ZSTD_getDecompressedSize() :
+ *  NOTE: This function is now obsolete, in favor of ZSTD_getFrameContentSize().
+ *  Both functions work the same way,
+ *  but ZSTD_getDecompressedSize() blends
+ *  "empty", "unknown" and "error" results in the same return value (0),
+ *  while ZSTD_getFrameContentSize() distinguishes them.
+ *
+ *  'src' is the start of a zstd compressed frame.
+ *  @return : content size to be decompressed, as a 64-bits value _if known and not empty_, 0 otherwise. */
 ZSTDLIB_API unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize);
 
 
@@ -137,29 +151,35 @@ ZSTDLIB_API size_t     ZSTD_freeCCtx(ZSTD_CCtx* cctx);
 
 /*! ZSTD_compressCCtx() :
  *  Same as ZSTD_compress(), requires an allocated ZSTD_CCtx (see ZSTD_createCCtx()). */
-ZSTDLIB_API size_t ZSTD_compressCCtx(ZSTD_CCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize, int compressionLevel);
+ZSTDLIB_API size_t ZSTD_compressCCtx(ZSTD_CCtx* ctx,
+                                     void* dst, size_t dstCapacity,
+                               const void* src, size_t srcSize,
+                                     int compressionLevel);
 
 /*= Decompression context
  *  When decompressing many times,
- *  it is recommended to allocate a context just once, and re-use it for each successive compression operation.
+ *  it is recommended to allocate a context only once,
+ *  and re-use it for each successive compression operation.
  *  This will make workload friendlier for system's memory.
- *  Use one context per thread for parallel execution in multi-threaded environments. */
+ *  Use one context per thread for parallel execution. */
 typedef struct ZSTD_DCtx_s ZSTD_DCtx;
 ZSTDLIB_API ZSTD_DCtx* ZSTD_createDCtx(void);
 ZSTDLIB_API size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);
 
 /*! ZSTD_decompressDCtx() :
- *  Same as ZSTD_decompress(), requires an allocated ZSTD_DCtx (see ZSTD_createDCtx()). */
-ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
+ *  Same as ZSTD_decompress(), requires an allocated ZSTD_DCtx (see ZSTD_createDCtx()) */
+ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* ctx,
+                                       void* dst, size_t dstCapacity,
+                                 const void* src, size_t srcSize);
 
 
 /**************************
 *  Simple dictionary API
 ***************************/
 /*! ZSTD_compress_usingDict() :
-*   Compression using a predefined Dictionary (see dictBuilder/zdict.h).
-*   Note : This function loads the dictionary, resulting in significant startup delay.
-*   Note : When `dict == NULL || dictSize < 8` no dictionary is used. */
+ *  Compression using a predefined Dictionary (see dictBuilder/zdict.h).
+ *  Note : This function loads the dictionary, resulting in significant startup delay.
+ *  Note : When `dict == NULL || dictSize < 8` no dictionary is used. */
 ZSTDLIB_API size_t ZSTD_compress_usingDict(ZSTD_CCtx* ctx,
                                            void* dst, size_t dstCapacity,
                                      const void* src, size_t srcSize,
@@ -167,30 +187,31 @@ ZSTDLIB_API size_t ZSTD_compress_usingDict(ZSTD_CCtx* ctx,
                                            int compressionLevel);
 
 /*! ZSTD_decompress_usingDict() :
-*   Decompression using a predefined Dictionary (see dictBuilder/zdict.h).
-*   Dictionary must be identical to the one used during compression.
-*   Note : This function loads the dictionary, resulting in significant startup delay.
-*   Note : When `dict == NULL || dictSize < 8` no dictionary is used. */
+ *  Decompression using a predefined Dictionary (see dictBuilder/zdict.h).
+ *  Dictionary must be identical to the one used during compression.
+ *  Note : This function loads the dictionary, resulting in significant startup delay.
+ *  Note : When `dict == NULL || dictSize < 8` no dictionary is used. */
 ZSTDLIB_API size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
                                              void* dst, size_t dstCapacity,
                                        const void* src, size_t srcSize,
                                        const void* dict,size_t dictSize);
 
 
-/****************************
-*  Fast dictionary API
-****************************/
+/**********************************
+ *  Bulk processing dictionary API
+ *********************************/
 typedef struct ZSTD_CDict_s ZSTD_CDict;
 
 /*! ZSTD_createCDict() :
-*   When compressing multiple messages / blocks with the same dictionary, it's recommended to load it just once.
-*   ZSTD_createCDict() will create a digested dictionary, ready to start future compression operations without startup delay.
-*   ZSTD_CDict can be created once and used by multiple threads concurrently, as its usage is read-only.
-*   `dictBuffer` can be released after ZSTD_CDict creation, as its content is copied within CDict */
-ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize, int compressionLevel);
+ *  When compressing multiple messages / blocks with the same dictionary, it's recommended to load it just once.
+ *  ZSTD_createCDict() will create a digested dictionary, ready to start future compression operations without startup delay.
+ *  ZSTD_CDict can be created once and shared by multiple threads concurrently, since its usage is read-only.
+ *  `dictBuffer` can be released after ZSTD_CDict creation, since its content is copied within CDict */
+ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize,
+                                         int compressionLevel);
 
 /*! ZSTD_freeCDict() :
-*   Function frees memory allocated by ZSTD_createCDict(). */
+ *  Function frees memory allocated by ZSTD_createCDict(). */
 ZSTDLIB_API size_t      ZSTD_freeCDict(ZSTD_CDict* CDict);
 
 /*! ZSTD_compress_usingCDict() :
@@ -207,17 +228,17 @@ ZSTDLIB_API size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
 typedef struct ZSTD_DDict_s ZSTD_DDict;
 
 /*! ZSTD_createDDict() :
-*   Create a digested dictionary, ready to start decompression operation without startup delay.
-*   dictBuffer can be released after DDict creation, as its content is copied inside DDict */
+ *  Create a digested dictionary, ready to start decompression operation without startup delay.
+ *  dictBuffer can be released after DDict creation, as its content is copied inside DDict */
 ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict(const void* dictBuffer, size_t dictSize);
 
 /*! ZSTD_freeDDict() :
-*   Function frees memory allocated with ZSTD_createDDict() */
+ *  Function frees memory allocated with ZSTD_createDDict() */
 ZSTDLIB_API size_t      ZSTD_freeDDict(ZSTD_DDict* ddict);
 
 /*! ZSTD_decompress_usingDDict() :
-*   Decompression using a digested Dictionary.
-*   Faster startup than ZSTD_decompress_usingDict(), recommended when same dictionary is used multiple times. */
+ *  Decompression using a digested Dictionary.
+ *  Faster startup than ZSTD_decompress_usingDict(), recommended when same dictionary is used multiple times. */
 ZSTDLIB_API size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
                                               void* dst, size_t dstCapacity,
                                         const void* src, size_t srcSize,
@@ -274,14 +295,17 @@ typedef struct ZSTD_outBuffer_s {
 *  ZSTD_endStream() instructs to finish a frame.
 *  It will perform a flush and write frame epilogue.
 *  The epilogue is required for decoders to consider a frame completed.
-*  Similar to ZSTD_flushStream(), it may not be able to flush the full content if `output->size` is too small.
+*  ZSTD_endStream() may not be able to flush full data if `output->size` is too small.
 *  In which case, call again ZSTD_endStream() to complete the flush.
-*  @return : nb of bytes still present within internal buffer (0 if it's empty, hence compression completed)
+*  @return : 0 if frame fully completed and fully flushed,
+             or >0 if some data is still present within internal buffer
+                  (value is minimum size estimation for remaining data to flush, but it could be more)
 *            or an error code, which can be tested using ZSTD_isError().
 *
 * *******************************************************************/
 
-typedef struct ZSTD_CStream_s ZSTD_CStream;
+typedef ZSTD_CCtx ZSTD_CStream;  /**< CCtx and CStream are now effectively same object (>= v1.3.0) */
+                                 /* Continue to distinguish them for compatibility with versions <= v1.2.0 */
 /*===== ZSTD_CStream management functions =====*/
 ZSTDLIB_API ZSTD_CStream* ZSTD_createCStream(void);
 ZSTDLIB_API size_t ZSTD_freeCStream(ZSTD_CStream* zcs);
@@ -319,7 +343,8 @@ ZSTDLIB_API size_t ZSTD_CStreamOutSize(void);   /**< recommended size for output
 *            The return value is a suggested next input size (a hint to improve latency) that will never load more than the current frame.
 * *******************************************************************************/
 
-typedef struct ZSTD_DStream_s ZSTD_DStream;
+typedef ZSTD_DCtx ZSTD_DStream;  /**< DCtx and DStream are now effectively same object (>= v1.3.0) */
+                                 /* Continue to distinguish them for compatibility with versions <= v1.2.0 */
 /*===== ZSTD_DStream management functions =====*/
 ZSTDLIB_API ZSTD_DStream* ZSTD_createDStream(void);
 ZSTDLIB_API size_t ZSTD_freeDStream(ZSTD_DStream* zds);
@@ -334,23 +359,22 @@ ZSTDLIB_API size_t ZSTD_DStreamOutSize(void);   /*!< recommended size for output
 #endif  /* ZSTD_H_235446 */
 
 
-#if defined(ZSTD_STATIC_LINKING_ONLY) && !defined(ZSTD_H_ZSTD_STATIC_LINKING_ONLY)
-#define ZSTD_H_ZSTD_STATIC_LINKING_ONLY
 
 /****************************************************************************************
  * START OF ADVANCED AND EXPERIMENTAL FUNCTIONS
  * The definitions in this section are considered experimental.
- * They should never be used with a dynamic library, as they may change in the future.
- * They are provided for advanced usages.
+ * They should never be used with a dynamic library, as prototypes may change in the future.
+ * They are provided for advanced scenarios.
  * Use them only in association with static linking.
  * ***************************************************************************************/
 
+#if defined(ZSTD_STATIC_LINKING_ONLY) && !defined(ZSTD_H_ZSTD_STATIC_LINKING_ONLY)
+#define ZSTD_H_ZSTD_STATIC_LINKING_ONLY
+
 /* --- Constants ---*/
 #define ZSTD_MAGICNUMBER            0xFD2FB528   /* >= v0.8.0 */
 #define ZSTD_MAGIC_SKIPPABLE_START  0x184D2A50U
-
-#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1)
-#define ZSTD_CONTENTSIZE_ERROR   (0ULL - 2)
+#define ZSTD_MAGIC_DICTIONARY       0xEC30A437   /* v0.7+ */
 
 #define ZSTD_WINDOWLOG_MAX_32  27
 #define ZSTD_WINDOWLOG_MAX_64  27
@@ -370,14 +394,15 @@ ZSTDLIB_API size_t ZSTD_DStreamOutSize(void);   /*!< recommended size for output
 
 #define ZSTD_FRAMEHEADERSIZE_MAX 18    /* for static allocation */
 #define ZSTD_FRAMEHEADERSIZE_MIN  6
-static const size_t ZSTD_frameHeaderSize_prefix = 5;
-static const size_t ZSTD_frameHeaderSize_min = ZSTD_FRAMEHEADERSIZE_MIN;
+static const size_t ZSTD_frameHeaderSize_prefix = 5;  /* minimum input size to know frame header size */
 static const size_t ZSTD_frameHeaderSize_max = ZSTD_FRAMEHEADERSIZE_MAX;
+static const size_t ZSTD_frameHeaderSize_min = ZSTD_FRAMEHEADERSIZE_MIN;
 static const size_t ZSTD_skippableHeaderSize = 8;  /* magic number + skippable frame length */
 
 
 /*--- Advanced types ---*/
-typedef enum { ZSTD_fast, ZSTD_dfast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2, ZSTD_btlazy2, ZSTD_btopt, ZSTD_btopt2 } ZSTD_strategy;   /* from faster to stronger */
+typedef enum { ZSTD_fast=1, ZSTD_dfast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2,
+               ZSTD_btlazy2, ZSTD_btopt, ZSTD_btultra } ZSTD_strategy;   /* from faster to stronger */
 
 typedef struct {
     unsigned windowLog;      /**< largest match distance : larger == more compression, more memory needed during decompression */
@@ -400,76 +425,141 @@ typedef struct {
     ZSTD_frameParameters fParams;
 } ZSTD_parameters;
 
+typedef struct {
+    unsigned long long frameContentSize;
+    size_t windowSize;
+    unsigned dictID;
+    unsigned checksumFlag;
+} ZSTD_frameHeader;
+
 /*= Custom memory allocation functions */
 typedef void* (*ZSTD_allocFunction) (void* opaque, size_t size);
 typedef void  (*ZSTD_freeFunction) (void* opaque, void* address);
 typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; void* opaque; } ZSTD_customMem;
+/* use this constant to defer to stdlib's functions */
+static const ZSTD_customMem ZSTD_defaultCMem = { NULL, NULL, NULL };
+
 
 /***************************************
-*  Compressed size functions
+*  Frame size functions
 ***************************************/
 
 /*! ZSTD_findFrameCompressedSize() :
  *  `src` should point to the start of a ZSTD encoded frame or skippable frame
  *  `srcSize` must be at least as large as the frame
- *  @return : the compressed size of the frame pointed to by `src`, suitable to pass to
- *      `ZSTD_decompress` or similar, or an error code if given invalid input. */
+ *  @return : the compressed size of the first frame starting at `src`,
+ *            suitable to pass to `ZSTD_decompress` or similar,
+ *            or an error code if input is invalid */
 ZSTDLIB_API size_t ZSTD_findFrameCompressedSize(const void* src, size_t srcSize);
 
+/*! ZSTD_findDecompressedSize() :
+ *  `src` should point the start of a series of ZSTD encoded and/or skippable frames
+ *  `srcSize` must be the _exact_ size of this series
+ *       (i.e. there should be a frame boundary exactly at `srcSize` bytes after `src`)
+ *  @return : - decompressed size of all data in all successive frames
+ *            - if the decompressed size cannot be determined: ZSTD_CONTENTSIZE_UNKNOWN
+ *            - if an error occurred: ZSTD_CONTENTSIZE_ERROR
+ *
+ *   note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
+ *            When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size.
+ *            In which case, it's necessary to use streaming mode to decompress data.
+ *   note 2 : decompressed size is always present when compression is done with ZSTD_compress()
+ *   note 3 : decompressed size can be very large (64-bits value),
+ *            potentially larger than what local system can handle as a single memory segment.
+ *            In which case, it's necessary to use streaming mode to decompress data.
+ *   note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
+ *            Always ensure result fits within application's authorized limits.
+ *            Each application can set its own limits.
+ *   note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to
+ *            read each contained frame header.  This is fast as most of the data is skipped,
+ *            however it does mean that all frame data must be present and valid. */
+ZSTDLIB_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);
+
+/*! ZSTD_frameHeaderSize() :
+*   `src` should point to the start of a ZSTD frame
+*   `srcSize` must be >= ZSTD_frameHeaderSize_prefix.
+*   @return : size of the Frame Header */
+ZSTDLIB_API size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize);
+
+
 /***************************************
-*  Decompressed size functions
+*  Context memory usage
 ***************************************/
-/*! ZSTD_getFrameContentSize() :
-*   `src` should point to the start of a ZSTD encoded frame
-*   `srcSize` must be at least as large as the frame header.  A value greater than or equal
-*       to `ZSTD_frameHeaderSize_max` is guaranteed to be large enough in all cases.
-*   @return : decompressed size of the frame pointed to be `src` if known, otherwise
-*             - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined
-*             - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) */
-ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
 
-/*! ZSTD_findDecompressedSize() :
-*   `src` should point the start of a series of ZSTD encoded and/or skippable frames
-*   `srcSize` must be the _exact_ size of this series
-*       (i.e. there should be a frame boundary exactly `srcSize` bytes after `src`)
-*   @return : the decompressed size of all data in the contained frames, as a 64-bit value _if known_
-*             - if the decompressed size cannot be determined: ZSTD_CONTENTSIZE_UNKNOWN
-*             - if an error occurred: ZSTD_CONTENTSIZE_ERROR
-*
-*    note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
-*             When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size.
-*             In which case, it's necessary to use streaming mode to decompress data.
-*             Optionally, application can still use ZSTD_decompress() while relying on implied limits.
-*             (For example, data may be necessarily cut into blocks <= 16 KB).
-*    note 2 : decompressed size is always present when compression is done with ZSTD_compress()
-*    note 3 : decompressed size can be very large (64-bits value),
-*             potentially larger than what local system can handle as a single memory segment.
-*             In which case, it's necessary to use streaming mode to decompress data.
-*    note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
-*             Always ensure result fits within application's authorized limits.
-*             Each application can set its own limits.
-*    note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to
-*             read each contained frame header.  This is efficient as most of the data is skipped,
-*             however it does mean that all frame data must be present and valid. */
-ZSTDLIB_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);
+/*! ZSTD_sizeof_*() :
+ *  These functions give the current memory usage of selected object.
+ *  Object memory usage can evolve if it's re-used multiple times. */
+ZSTDLIB_API size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
+ZSTDLIB_API size_t ZSTD_sizeof_DCtx(const ZSTD_DCtx* dctx);
+ZSTDLIB_API size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs);
+ZSTDLIB_API size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds);
+ZSTDLIB_API size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict);
+ZSTDLIB_API size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
+
+/*! ZSTD_estimate*() :
+ *  These functions make it possible to estimate memory usage
+ *  of a future {D,C}Ctx, before its creation.
+ *  ZSTD_estimateCCtxSize() will provide a budget large enough for any compression level up to selected one.
+ *  It will also consider src size to be arbitrarily "large", which is worst case.
+ *  If srcSize is known to always be small, ZSTD_estimateCCtxSize_advanced() can provide a tighter estimation.
+ *  ZSTD_estimateCCtxSize_advanced() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel.
+ *  Note : CCtx estimation is only correct for single-threaded compression */
+ZSTDLIB_API size_t ZSTD_estimateCCtxSize(int compressionLevel);
+ZSTDLIB_API size_t ZSTD_estimateCCtxSize_advanced(ZSTD_compressionParameters cParams);
+ZSTDLIB_API size_t ZSTD_estimateDCtxSize(void);
+
+/*! ZSTD_estimate?StreamSize() :
+ *  ZSTD_estimateCStreamSize() will provide a budget large enough for any compression level up to selected one.
+ *  It will also consider src size to be arbitrarily "large", which is worst case.
+ *  If srcSize is known to always be small, ZSTD_estimateCStreamSize_advanced() can provide a tighter estimation.
+ *  ZSTD_estimateCStreamSize_advanced() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel.
+ *  Note : CStream estimation is only correct for single-threaded compression.
+ *  ZSTD_DStream memory budget depends on window Size.
+ *  This information can be passed manually, using ZSTD_estimateDStreamSize,
+ *  or deducted from a valid frame Header, using ZSTD_estimateDStreamSize_fromFrame();
+ *  Note : if streaming is init with function ZSTD_init?Stream_usingDict(),
+ *         an internal ?Dict will be created, which additional size is not estimated here.
+ *         In this case, get total size by adding ZSTD_estimate?DictSize */
+ZSTDLIB_API size_t ZSTD_estimateCStreamSize(int compressionLevel);
+ZSTDLIB_API size_t ZSTD_estimateCStreamSize_advanced(ZSTD_compressionParameters cParams);
+ZSTDLIB_API size_t ZSTD_estimateDStreamSize(size_t windowSize);
+ZSTDLIB_API size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize);
+
+/*! ZSTD_estimate?DictSize() :
+ *  ZSTD_estimateCDictSize() will bet that src size is relatively "small", and content is copied, like ZSTD_createCDict().
+ *  ZSTD_estimateCStreamSize_advanced() makes it possible to control precisely compression parameters, like ZSTD_createCDict_advanced().
+ *  Note : dictionary created "byReference" are smaller */
+ZSTDLIB_API size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel);
+ZSTDLIB_API size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, unsigned byReference);
+ZSTDLIB_API size_t ZSTD_estimateDDictSize(size_t dictSize, unsigned byReference);
 
 
 /***************************************
 *  Advanced compression functions
 ***************************************/
-/*! ZSTD_estimateCCtxSize() :
- *  Gives the amount of memory allocated for a ZSTD_CCtx given a set of compression parameters.
- *  `frameContentSize` is an optional parameter, provide `0` if unknown */
-ZSTDLIB_API size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams);
-
 /*! ZSTD_createCCtx_advanced() :
  *  Create a ZSTD compression context using external alloc and free functions */
 ZSTDLIB_API ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem);
 
-/*! ZSTD_sizeofCCtx() :
- *  Gives the amount of memory used by a given ZSTD_CCtx */
-ZSTDLIB_API size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
+/*! ZSTD_initStaticCCtx() : initialize a fixed-size zstd compression context
+ *  workspace: The memory area to emplace the context into.
+ *             Provided pointer must 8-bytes aligned.
+ *             It must outlive context usage.
+ *  workspaceSize: Use ZSTD_estimateCCtxSize() or ZSTD_estimateCStreamSize()
+ *                 to determine how large workspace must be to support scenario.
+ * @return : pointer to ZSTD_CCtx*, or NULL if error (size too small)
+ *  Note : zstd will never resize nor malloc() when using a static cctx.
+ *         If it needs more memory than available, it will simply error out.
+ *  Note 2 : there is no corresponding "free" function.
+ *           Since workspace was allocated externally, it must be freed externally too.
+ *  Limitation 1 : currently not compatible with internal CDict creation, such as
+ *                 ZSTD_CCtx_loadDictionary() or ZSTD_initCStream_usingDict().
+ *  Limitation 2 : currently not compatible with multi-threading
+ */
+ZSTDLIB_API ZSTD_CCtx* ZSTD_initStaticCCtx(void* workspace, size_t workspaceSize);
+
 
+/* !!! To be deprecated !!! */
 typedef enum {
     ZSTD_p_forceWindow,   /* Force back-references to remain < windowSize, even when referencing Dictionary content (default:0) */
     ZSTD_p_forceRawDict   /* Force loading dictionary in "content-only" mode (no header analysis) */
@@ -479,20 +569,43 @@ typedef enum {
  *  @result : 0, or an error code (which can be tested with ZSTD_isError()) */
 ZSTDLIB_API size_t ZSTD_setCCtxParameter(ZSTD_CCtx* cctx, ZSTD_CCtxParameter param, unsigned value);
 
+
 /*! ZSTD_createCDict_byReference() :
  *  Create a digested dictionary for compression
  *  Dictionary content is simply referenced, and therefore stays in dictBuffer.
  *  It is important that dictBuffer outlives CDict, it must remain read accessible throughout the lifetime of CDict */
 ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict_byReference(const void* dictBuffer, size_t dictSize, int compressionLevel);
 
+
+typedef enum { ZSTD_dm_auto=0,        /* dictionary is "full" if it starts with ZSTD_MAGIC_DICTIONARY, otherwise it is "rawContent" */
+               ZSTD_dm_rawContent,    /* ensures dictionary is always loaded as rawContent, even if it starts with ZSTD_MAGIC_DICTIONARY */
+               ZSTD_dm_fullDict       /* refuses to load a dictionary if it does not respect Zstandard's specification */
+} ZSTD_dictMode_e;
 /*! ZSTD_createCDict_advanced() :
  *  Create a ZSTD_CDict using external alloc and free, and customized compression parameters */
-ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize, unsigned byReference,
-                                                  ZSTD_compressionParameters cParams, ZSTD_customMem customMem);
-
-/*! ZSTD_sizeof_CDict() :
- *  Gives the amount of memory used by a given ZSTD_sizeof_CDict */
-ZSTDLIB_API size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict);
+ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize,
+                                                  unsigned byReference, ZSTD_dictMode_e dictMode,
+                                                  ZSTD_compressionParameters cParams,
+                                                  ZSTD_customMem customMem);
+
+/*! ZSTD_initStaticCDict_advanced() :
+ *  Generate a digested dictionary in provided memory area.
+ *  workspace: The memory area to emplace the dictionary into.
+ *             Provided pointer must 8-bytes aligned.
+ *             It must outlive dictionary usage.
+ *  workspaceSize: Use ZSTD_estimateCDictSize()
+ *                 to determine how large workspace must be.
+ *  cParams : use ZSTD_getCParams() to transform a compression level
+ *            into its relevants cParams.
+ * @return : pointer to ZSTD_CDict*, or NULL if error (size too small)
+ *  Note : there is no corresponding "free" function.
+ *         Since workspace was allocated externally, it must be freed externally.
+ */
+ZSTDLIB_API ZSTD_CDict* ZSTD_initStaticCDict(
+                            void* workspace, size_t workspaceSize,
+                      const void* dict, size_t dictSize,
+                            unsigned byReference, ZSTD_dictMode_e dictMode,
+                            ZSTD_compressionParameters cParams);
 
 /*! ZSTD_getCParams() :
 *   @return ZSTD_compressionParameters structure for a selected compression level and estimated srcSize.
@@ -509,8 +622,8 @@ ZSTDLIB_API ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long l
 ZSTDLIB_API size_t ZSTD_checkCParams(ZSTD_compressionParameters params);
 
 /*! ZSTD_adjustCParams() :
-*   optimize params for a given `srcSize` and `dictSize`.
-*   both values are optional, select `0` if unknown. */
+ *  optimize params for a given `srcSize` and `dictSize`.
+ *  both values are optional, select `0` if unknown. */
 ZSTDLIB_API ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize);
 
 /*! ZSTD_compress_advanced() :
@@ -538,22 +651,32 @@ ZSTDLIB_API size_t ZSTD_compress_usingCDict_advanced(ZSTD_CCtx* cctx,
  *  Note 3 : Skippable Frame Identifiers are considered valid. */
 ZSTDLIB_API unsigned ZSTD_isFrame(const void* buffer, size_t size);
 
-/*! ZSTD_estimateDCtxSize() :
- *  Gives the potential amount of memory allocated to create a ZSTD_DCtx */
-ZSTDLIB_API size_t ZSTD_estimateDCtxSize(void);
-
 /*! ZSTD_createDCtx_advanced() :
  *  Create a ZSTD decompression context using external alloc and free functions */
 ZSTDLIB_API ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem);
 
-/*! ZSTD_sizeof_DCtx() :
- *  Gives the amount of memory used by a given ZSTD_DCtx */
-ZSTDLIB_API size_t ZSTD_sizeof_DCtx(const ZSTD_DCtx* dctx);
+/*! ZSTD_initStaticDCtx() : initialize a fixed-size zstd decompression context
+ *  workspace: The memory area to emplace the context into.
+ *             Provided pointer must 8-bytes aligned.
+ *             It must outlive context usage.
+ *  workspaceSize: Use ZSTD_estimateDCtxSize() or ZSTD_estimateDStreamSize()
+ *                 to determine how large workspace must be to support scenario.
+ * @return : pointer to ZSTD_DCtx*, or NULL if error (size too small)
+ *  Note : zstd will never resize nor malloc() when using a static dctx.
+ *         If it needs more memory than available, it will simply error out.
+ *  Note 2 : static dctx is incompatible with legacy support
+ *  Note 3 : there is no corresponding "free" function.
+ *           Since workspace was allocated externally, it must be freed externally.
+ *  Limitation : currently not compatible with internal DDict creation,
+ *               such as ZSTD_initDStream_usingDict().
+ */
+ZSTDLIB_API ZSTD_DCtx* ZSTD_initStaticDCtx(void* workspace, size_t workspaceSize);
 
 /*! ZSTD_createDDict_byReference() :
  *  Create a digested dictionary, ready to start decompression operation without startup delay.
- *  Dictionary content is simply referenced, and therefore stays in dictBuffer.
- *  It is important that dictBuffer outlives DDict, it must remain read accessible throughout the lifetime of DDict */
+ *  Dictionary content is referenced, and therefore stays in dictBuffer.
+ *  It is important that dictBuffer outlives DDict,
+ *  it must remain read accessible throughout the lifetime of DDict */
 ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize);
 
 /*! ZSTD_createDDict_advanced() :
@@ -561,9 +684,20 @@ ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, siz
 ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize,
                                                   unsigned byReference, ZSTD_customMem customMem);
 
-/*! ZSTD_sizeof_DDict() :
- *  Gives the amount of memory used by a given ZSTD_DDict */
-ZSTDLIB_API size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
+/*! ZSTD_initStaticDDict() :
+ *  Generate a digested dictionary in provided memory area.
+ *  workspace: The memory area to emplace the dictionary into.
+ *             Provided pointer must 8-bytes aligned.
+ *             It must outlive dictionary usage.
+ *  workspaceSize: Use ZSTD_estimateDDictSize()
+ *                 to determine how large workspace must be.
+ * @return : pointer to ZSTD_DDict*, or NULL if error (size too small)
+ *  Note : there is no corresponding "free" function.
+ *         Since workspace was allocated externally, it must be freed externally.
+ */
+ZSTDLIB_API ZSTD_DDict* ZSTD_initStaticDDict(void* workspace, size_t workspaceSize,
+                                             const void* dict, size_t dictSize,
+                                             unsigned byReference);
 
 /*! ZSTD_getDictID_fromDict() :
  *  Provides the dictID stored within dictionary.
@@ -586,7 +720,7 @@ ZSTDLIB_API unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict);
  *    Note : this use case also happens when using a non-conformant dictionary.
  *  - `srcSize` is too small, and as a result, the frame header could not be decoded (only possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`).
  *  - This is not a Zstandard frame.
- *  When identifying the exact failure cause, it's possible to use ZSTD_getFrameParams(), which will provide a more precise error code. */
+ *  When identifying the exact failure cause, it's possible to use ZSTD_getFrameHeader(), which will provide a more precise error code. */
 ZSTDLIB_API unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize);
 
 
@@ -596,13 +730,13 @@ ZSTDLIB_API unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize);
 
 /*=====   Advanced Streaming compression functions  =====*/
 ZSTDLIB_API ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem);
-ZSTDLIB_API size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs);   /**< size of CStream is variable, depending primarily on compression level */
+ZSTDLIB_API ZSTD_CStream* ZSTD_initStaticCStream(void* workspace, size_t workspaceSize);    /**< same as ZSTD_initStaticCCtx() */
 ZSTDLIB_API size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize);   /**< pledgedSrcSize must be correct, a size of 0 means unknown.  for a frame size of 0 use initCStream_advanced */
-ZSTDLIB_API size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); /**< note: a dict will not be used if dict == NULL or dictSize < 8 */
+ZSTDLIB_API size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); /**< creates of an internal CDict (incompatible with static CCtx), except if dict == NULL or dictSize < 8, in which case no dict is used. */
 ZSTDLIB_API size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, const void* dict, size_t dictSize,
                                              ZSTD_parameters params, unsigned long long pledgedSrcSize);  /**< pledgedSrcSize is optional and can be 0 (meaning unknown). note: if the contentSizeFlag is set, pledgedSrcSize == 0 means the source size is actually 0 */
 ZSTDLIB_API size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict);  /**< note : cdict will just be referenced, and must outlive compression session */
-ZSTDLIB_API size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize, ZSTD_frameParameters fParams);  /**< same as ZSTD_initCStream_usingCDict(), with control over frame parameters */
+ZSTDLIB_API size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, ZSTD_frameParameters fParams, unsigned long long pledgedSrcSize);  /**< same as ZSTD_initCStream_usingCDict(), with control over frame parameters */
 
 /*! ZSTD_resetCStream() :
  *  start a new compression job, using same parameters from previous job.
@@ -617,11 +751,11 @@ ZSTDLIB_API size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledg
 /*=====   Advanced Streaming decompression functions  =====*/
 typedef enum { DStream_p_maxWindowSize } ZSTD_DStreamParameter_e;
 ZSTDLIB_API ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem);
-ZSTDLIB_API size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); /**< note: a dict will not be used if dict == NULL or dictSize < 8 */
+ZSTDLIB_API ZSTD_DStream* ZSTD_initStaticDStream(void* workspace, size_t workspaceSize);    /**< same as ZSTD_initStaticDCtx() */
 ZSTDLIB_API size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds, ZSTD_DStreamParameter_e paramType, unsigned paramValue);
+ZSTDLIB_API size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); /**< note: a dict will not be used if dict == NULL or dictSize < 8 */
 ZSTDLIB_API size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict);  /**< note : ddict will just be referenced, and must outlive decompression session */
 ZSTDLIB_API size_t ZSTD_resetDStream(ZSTD_DStream* zds);  /**< re-use decompression parameters from previous init; saves dictionary loading */
-ZSTDLIB_API size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds);
 
 
 /*********************************************************************
@@ -683,21 +817,24 @@ ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapaci
   Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it.
   A ZSTD_DCtx object can be re-used multiple times.
 
-  First typical operation is to retrieve frame parameters, using ZSTD_getFrameParams().
-  It fills a ZSTD_frameParams structure which provide important information to correctly decode the frame,
-  such as the minimum rolling buffer size to allocate to decompress data (`windowSize`),
-  and the dictionary ID used.
+  First typical operation is to retrieve frame parameters, using ZSTD_getFrameHeader().
+  It fills a ZSTD_frameHeader structure with important information to correctly decode the frame,
+  such as minimum rolling buffer size to allocate to decompress data (`windowSize`),
+  and the dictionary ID in use.
   (Note : content size is optional, it may not be present. 0 means : content size unknown).
   Note that these values could be wrong, either because of data malformation, or because an attacker is spoofing deliberate false information.
   As a consequence, check that values remain within valid application range, especially `windowSize`, before allocation.
-  Each application can set its own limit, depending on local restrictions. For extended interoperability, it is recommended to support at least 8 MB.
-  Frame parameters are extracted from the beginning of the compressed frame.
-  Data fragment must be large enough to ensure successful decoding, typically `ZSTD_frameHeaderSize_max` bytes.
-  @result : 0 : successful decoding, the `ZSTD_frameParams` structure is correctly filled.
+  Each application can set its own limit, depending on local restrictions.
+  For extended interoperability, it is recommended to support windowSize of at least 8 MB.
+  Frame header is extracted from the beginning of compressed frame, so providing only the frame's beginning is enough.
+  Data fragment must be large enough to ensure successful decoding.
+  `ZSTD_frameHeaderSize_max` bytes is guaranteed to always be large enough.
+  @result : 0 : successful decoding, the `ZSTD_frameHeader` structure is correctly filled.
            >0 : `srcSize` is too small, please provide at least @result bytes on next attempt.
            errorCode, which can be tested using ZSTD_isError().
 
-  Start decompression, with ZSTD_decompressBegin() or ZSTD_decompressBegin_usingDict().
+  Start decompression, with ZSTD_decompressBegin().
+  If decompression requires a dictionary, use ZSTD_decompressBegin_usingDict() or ZSTD_decompressBegin_usingDDict().
   Alternatively, you can copy a prepared context, using ZSTD_copyDCtx().
 
   Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue() alternatively.
@@ -729,30 +866,233 @@ ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapaci
   b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits
   c) Frame Content - any content (User Data) of length equal to Frame Size
   For skippable frames ZSTD_decompressContinue() always returns 0.
-  For skippable frames ZSTD_getFrameParams() returns fparamsPtr->windowLog==0 what means that a frame is skippable.
+  For skippable frames ZSTD_getFrameHeader() returns fparamsPtr->windowLog==0 what means that a frame is skippable.
     Note : If fparamsPtr->frameContentSize==0, it is ambiguous: the frame might actually be a Zstd encoded frame with no content.
            For purposes of decompression, it is valid in both cases to skip the frame using
            ZSTD_findFrameCompressedSize to find its size in bytes.
   It also returns Frame Size as fparamsPtr->frameContentSize.
 */
 
-typedef struct {
-    unsigned long long frameContentSize;
-    unsigned windowSize;
-    unsigned dictID;
-    unsigned checksumFlag;
-} ZSTD_frameParams;
-
 /*=====   Buffer-less streaming decompression functions  =====*/
-ZSTDLIB_API size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t srcSize);   /**< doesn't consume input, see details below */
+ZSTDLIB_API size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize);   /**< doesn't consume input */
 ZSTDLIB_API size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx);
 ZSTDLIB_API size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
+ZSTDLIB_API size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict);
 ZSTDLIB_API void   ZSTD_copyDCtx(ZSTD_DCtx* dctx, const ZSTD_DCtx* preparedDCtx);
+
 ZSTDLIB_API size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx);
 ZSTDLIB_API size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 typedef enum { ZSTDnit_frameHeader, ZSTDnit_blockHeader, ZSTDnit_block, ZSTDnit_lastBlock, ZSTDnit_checksum, ZSTDnit_skippableFrame } ZSTD_nextInputType_e;
 ZSTDLIB_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
 
+
+
+/*===   New advanced API (experimental, and compression only)  ===*/
+
+/* notes on API design :
+ *   In this proposal, parameters are pushed one by one into an existing CCtx,
+ *   and then applied on all subsequent compression jobs.
+ *   When no parameter is ever provided, CCtx is created with compression level ZSTD_CLEVEL_DEFAULT.
+ *
+ *   This API is intended to replace all others experimental API.
+ *   It can basically do all other use cases, and even new ones.
+ *   It stands a good chance to become "stable",
+ *   after a reasonable testing period.
+ */
+
+/* note on naming convention :
+ *   Initially, the API favored names like ZSTD_setCCtxParameter() .
+ *   In this proposal, convention is changed towards ZSTD_CCtx_setParameter() .
+ *   The main driver is that it identifies more clearly the target object type.
+ *   It feels clearer in light of potential variants :
+ *   ZSTD_CDict_setParameter() (rather than ZSTD_setCDictParameter())
+ *   ZSTD_DCtx_setParameter()  (rather than ZSTD_setDCtxParameter() )
+ *   Left variant feels easier to distinguish.
+ */
+
+/* note on enum design :
+ * All enum will be manually set to explicit values before reaching "stable API" status */
+
+typedef enum {
+    /* compression parameters */
+    ZSTD_p_compressionLevel=100, /* Update all compression parameters according to pre-defined cLevel table
+                              * Default level is ZSTD_CLEVEL_DEFAULT==3.
+                              * Special: value 0 means "do not change cLevel". */
+    ZSTD_p_windowLog,        /* Maximum allowed back-reference distance, expressed as power of 2.
+                              * Must be clamped between ZSTD_WINDOWLOG_MIN and ZSTD_WINDOWLOG_MAX.
+                              * Special: value 0 means "do not change windowLog". */
+    ZSTD_p_hashLog,          /* Size of the probe table, as a power of 2.
+                              * Resulting table size is (1 << (hashLog+2)).
+                              * Must be clamped between ZSTD_HASHLOG_MIN and ZSTD_HASHLOG_MAX.
+                              * Larger tables improve compression ratio of strategies <= dFast,
+                              * and improve speed of strategies > dFast.
+                              * Special: value 0 means "do not change hashLog". */
+    ZSTD_p_chainLog,         /* Size of the full-search table, as a power of 2.
+                              * Resulting table size is (1 << (chainLog+2)).
+                              * Larger tables result in better and slower compression.
+                              * This parameter is useless when using "fast" strategy.
+                              * Special: value 0 means "do not change chainLog". */
+    ZSTD_p_searchLog,        /* Number of search attempts, as a power of 2.
+                              * More attempts result in better and slower compression.
+                              * This parameter is useless when using "fast" and "dFast" strategies.
+                              * Special: value 0 means "do not change searchLog". */
+    ZSTD_p_minMatch,         /* Minimum size of searched matches (note : repCode matches can be smaller).
+                              * Larger values make faster compression and decompression, but decrease ratio.
+                              * Must be clamped between ZSTD_SEARCHLENGTH_MIN and ZSTD_SEARCHLENGTH_MAX.
+                              * Note that currently, for all strategies < btopt, effective minimum is 4.
+                              * Note that currently, for all strategies > fast, effective maximum is 6.
+                              * Special: value 0 means "do not change minMatchLength". */
+    ZSTD_p_targetLength,     /* Only useful for strategies >= btopt.
+                              * Length of Match considered "good enough" to stop search.
+                              * Larger values make compression stronger and slower.
+                              * Special: value 0 means "do not change targetLength". */
+    ZSTD_p_compressionStrategy, /* See ZSTD_strategy enum definition.
+                              * Cast selected strategy as unsigned for ZSTD_CCtx_setParameter() compatibility.
+                              * The higher the value of selected strategy, the more complex it is,
+                              * resulting in stronger and slower compression.
+                              * Special: value 0 means "do not change strategy". */
+
+    /* frame parameters */
+    ZSTD_p_contentSizeFlag=200, /* Content size is written into frame header _whenever known_ (default:1) */
+    ZSTD_p_checksumFlag,     /* A 32-bits checksum of content is written at end of frame (default:0) */
+    ZSTD_p_dictIDFlag,       /* When applicable, dictID of dictionary is provided in frame header (default:1) */
+
+    /* dictionary parameters (must be set before ZSTD_CCtx_loadDictionary) */
+    ZSTD_p_dictMode=300,     /* Select how dictionary content must be interpreted. Value must be from type ZSTD_dictMode_e.
+                              * default : 0==auto : dictionary will be "full" if it respects specification, otherwise it will be "rawContent" */
+    ZSTD_p_refDictContent,   /* Dictionary content will be referenced, instead of copied (default:0==byCopy).
+                              * It requires that dictionary buffer outlives its users */
+
+    /* multi-threading parameters */
+    ZSTD_p_nbThreads=400,    /* Select how many threads a compression job can spawn (default:1)
+                              * More threads improve speed, but also increase memory usage.
+                              * Can only receive a value > 1 if ZSTD_MULTITHREAD is enabled.
+                              * Special: value 0 means "do not change nbThreads" */
+    ZSTD_p_jobSize,          /* Size of a compression job. Each compression job is completed in parallel.
+                              * 0 means default, which is dynamically determined based on compression parameters.
+                              * Job size must be a minimum of overlapSize, or 1 KB, whichever is largest
+                              * The minimum size is automatically and transparently enforced */
+    ZSTD_p_overlapSizeLog,   /* Size of previous input reloaded at the beginning of each job.
+                              * 0 => no overlap, 6(default) => use 1/8th of windowSize, >=9 => use full windowSize */
+
+    /* advanced parameters - may not remain available after API update */
+    ZSTD_p_forceMaxWindow=1100, /* Force back-reference distances to remain < windowSize,
+                              * even when referencing into Dictionary content (default:0) */
+
+} ZSTD_cParameter;
+
+
+/*! ZSTD_CCtx_setParameter() :
+ *  Set one compression parameter, selected by enum ZSTD_cParameter.
+ *  Note : when `value` is an enum, cast it to unsigned for proper type checking.
+ *  @result : 0, or an error code (which can be tested with ZSTD_isError()). */
+ZSTDLIB_API size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned value);
+
+/*! ZSTD_CCtx_setPledgedSrcSize() :
+ *  Total input data size to be compressed as a single frame.
+ *  This value will be controlled at the end, and result in error if not respected.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ *  Note 1 : 0 means zero, empty.
+ *           In order to mean "unknown content size", pass constant ZSTD_CONTENTSIZE_UNKNOWN.
+ *           Note that ZSTD_CONTENTSIZE_UNKNOWN is default value for new compression jobs.
+ *  Note 2 : If all data is provided and consumed in a single round,
+ *           this value is overriden by srcSize instead. */
+ZSTDLIB_API size_t ZSTD_CCtx_setPledgedSrcSize(ZSTD_CCtx* cctx, unsigned long long pledgedSrcSize);
+
+/*! ZSTD_CCtx_loadDictionary() :
+ *  Create an internal CDict from dict buffer.
+ *  Decompression will have to use same buffer.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ *  Special : Adding a NULL (or 0-size) dictionary invalidates any previous dictionary,
+ *            meaning "return to no-dictionary mode".
+ *  Note 1 : `dict` content will be copied internally,
+ *           except if ZSTD_p_refDictContent is set before loading.
+ *  Note 2 : Loading a dictionary involves building tables, which are dependent on compression parameters.
+ *           For this reason, compression parameters cannot be changed anymore after loading a dictionary.
+ *           It's also a CPU-heavy operation, with non-negligible impact on latency.
+ *  Note 3 : Dictionary will be used for all future compression jobs.
+ *           To return to "no-dictionary" situation, load a NULL dictionary */
+ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize);
+
+/*! ZSTD_CCtx_refCDict() :
+ *  Reference a prepared dictionary, to be used for all next compression jobs.
+ *  Note that compression parameters are enforced from within CDict,
+ *  and supercede any compression parameter previously set within CCtx.
+ *  The dictionary will remain valid for future compression jobs using same CCtx.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ *  Special : adding a NULL CDict means "return to no-dictionary mode".
+ *  Note 1 : Currently, only one dictionary can be managed.
+ *           Adding a new dictionary effectively "discards" any previous one.
+ *  Note 2 : CDict is just referenced, its lifetime must outlive CCtx.
+ */
+ZSTDLIB_API size_t ZSTD_CCtx_refCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict);
+
+/*! ZSTD_CCtx_refPrefix() :
+ *  Reference a prefix (single-usage dictionary) for next compression job.
+ *  Decompression need same prefix to properly regenerate data.
+ *  Prefix is **only used once**. Tables are discarded at end of compression job.
+ *  Subsequent compression jobs will be done without prefix (if none is explicitly referenced).
+ *  If there is a need to use same prefix multiple times, consider embedding it into a ZSTD_CDict instead.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ *  Special : Adding any prefix (including NULL) invalidates any previous prefix or dictionary
+ *  Note 1 : Prefix buffer is referenced. It must outlive compression job.
+ *  Note 2 : Referencing a prefix involves building tables, which are dependent on compression parameters.
+ *           It's a CPU-heavy operation, with non-negligible impact on latency.
+ *  Note 3 : it's possible to alter ZSTD_p_dictMode using ZSTD_CCtx_setParameter() */
+ZSTDLIB_API size_t ZSTD_CCtx_refPrefix(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize);
+
+
+
+typedef enum {
+    ZSTD_e_continue=0, /* collect more data, encoder transparently decides when to output result, for optimal conditions */
+    ZSTD_e_flush,      /* flush any data provided so far - frame will continue, future data can still reference previous data for better compression */
+    ZSTD_e_end         /* flush any remaining data and ends current frame. Any future compression starts a new frame. */
+} ZSTD_EndDirective;
+
+/*! ZSTD_compress_generic() :
+ *  Behave about the same as ZSTD_compressStream. To note :
+ *  - Compression parameters are pushed into CCtx before starting compression, using ZSTD_CCtx_setParameter()
+ *  - Compression parameters cannot be changed once compression is started.
+ *  - *dstPos must be <= dstCapacity, *srcPos must be <= srcSize
+ *  - *dspPos and *srcPos will be updated. They are guaranteed to remain below their respective limit.
+ *  - @return provides the minimum amount of data still to flush from internal buffers
+ *            or an error code, which can be tested using ZSTD_isError().
+ *            if @return != 0, flush is not fully completed, there is some data left within internal buffers.
+ *  - after a ZSTD_e_end directive, if internal buffer is not fully flushed,
+ *            only ZSTD_e_end or ZSTD_e_flush operations are allowed.
+ *            It is necessary to fully flush internal buffers
+ *            before starting a new compression job, or changing compression parameters.
+ */
+ZSTDLIB_API size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
+                                          ZSTD_outBuffer* output,
+                                          ZSTD_inBuffer* input,
+                                          ZSTD_EndDirective endOp);
+
+/*! ZSTD_CCtx_reset() :
+ *  Return a CCtx to clean state.
+ *  Useful after an error, or to interrupt an ongoing compression job and start a new one.
+ *  Any internal data not yet flushed is cancelled.
+ *  Dictionary (if any) is dropped.
+ *  It's possible to modify compression parameters after a reset.
+ */
+ZSTDLIB_API void ZSTD_CCtx_reset(ZSTD_CCtx* cctx);   /* Not ready yet ! */
+
+
+/*! ZSTD_compress_generic_simpleArgs() :
+ *  Same as ZSTD_compress_generic(),
+ *  but using only integral types as arguments.
+ *  Argument list is larger and less expressive than ZSTD_{in,out}Buffer,
+ *  but can be helpful for binders from dynamic languages
+ *  which have troubles handling structures containing memory pointers.
+ */
+size_t ZSTD_compress_generic_simpleArgs (
+                            ZSTD_CCtx* cctx,
+                            void* dst, size_t dstCapacity, size_t* dstPos,
+                      const void* src, size_t srcSize, size_t* srcPos,
+                            ZSTD_EndDirective endOp);
+
+
+
 /**
     Block functions
 
@@ -767,7 +1107,7 @@ ZSTDLIB_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
       + compression : any ZSTD_compressBegin*() variant, including with dictionary
       + decompression : any ZSTD_decompressBegin*() variant, including with dictionary
       + copyCCtx() and copyDCtx() can be used too
-    - Block size is limited, it must be <= ZSTD_getBlockSizeMax() <= ZSTD_BLOCKSIZE_ABSOLUTEMAX
+    - Block size is limited, it must be <= ZSTD_getBlockSize() <= ZSTD_BLOCKSIZE_MAX
       + If input is larger than a block size, it's necessary to split input data into multiple blocks
       + For inputs larger than a single block size, consider using the regular ZSTD_compress() instead.
         Frame metadata is not that costly, and quickly becomes negligible as source size grows larger.
@@ -780,9 +1120,10 @@ ZSTDLIB_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
         Use ZSTD_insertBlock() for such a case.
 */
 
-#define ZSTD_BLOCKSIZE_ABSOLUTEMAX (128 * 1024)   /* define, for static allocation */
+#define ZSTD_BLOCKSIZELOG_MAX 17
+#define ZSTD_BLOCKSIZE_MAX   (1<<ZSTD_BLOCKSIZELOG_MAX)   /* define, for static allocation */
 /*=====   Raw zstd block functions  =====*/
-ZSTDLIB_API size_t ZSTD_getBlockSizeMax(ZSTD_CCtx* cctx);
+ZSTDLIB_API size_t ZSTD_getBlockSize   (const ZSTD_CCtx* cctx);
 ZSTDLIB_API size_t ZSTD_compressBlock  (ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 ZSTDLIB_API size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 ZSTDLIB_API size_t ZSTD_insertBlock(ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize);  /**< insert block into `dctx` history. Useful for uncompressed blocks */
diff --git a/programs/Makefile b/programs/Makefile
index 0c920a87bcbd..8b080d446606 100644
--- a/programs/Makefile
+++ b/programs/Makefile
@@ -41,9 +41,11 @@ CPPFLAGS+= -I$(ZSTDDIR) -I$(ZSTDDIR)/common -I$(ZSTDDIR)/compress \
            -I$(ZSTDDIR)/dictBuilder \
            -DXXH_NAMESPACE=ZSTD_   # because xxhash.o already compiled with this macro from library
 CFLAGS  ?= -O3
-DEBUGFLAGS = -g -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
-          -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
-          -Wstrict-prototypes -Wundef -Wpointer-arith -Wformat-security
+DEBUGFLAGS = -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
+            -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
+            -Wstrict-prototypes -Wundef -Wpointer-arith -Wformat-security \
+            -Wvla -Wformat=2 -Winit-self -Wfloat-equal -Wwrite-strings \
+            -Wredundant-decls
 CFLAGS  += $(DEBUGFLAGS) $(MOREFLAGS)
 FLAGS    = $(CPPFLAGS) $(CFLAGS) $(LDFLAGS)
 
@@ -56,7 +58,7 @@ ZDICT_FILES := $(ZSTDDIR)/dictBuilder/*.c
 ZSTDDECOMP_O = $(ZSTDDIR)/decompress/zstd_decompress.o
 
 ZSTD_LEGACY_SUPPORT ?= 4
-ZSTDLEGACY_FILES:=
+ZSTDLEGACY_FILES :=
 ifneq ($(ZSTD_LEGACY_SUPPORT), 0)
 ifeq ($(shell test $(ZSTD_LEGACY_SUPPORT) -lt 8; echo $$?), 0)
 	ZSTDLEGACY_FILES += $(shell ls $(ZSTDDIR)/legacy/*.c | grep 'v0[$(ZSTD_LEGACY_SUPPORT)-7]')
@@ -137,16 +139,13 @@ all: zstd
 
 $(ZSTDDECOMP_O): CFLAGS += $(ALIGN_LOOP)
 
-zstd xzstd zstd4 xzstd4 : CPPFLAGS += $(THREAD_CPP) $(ZLIBCPP)
-zstd xzstd zstd4 xzstd4 : LDFLAGS += $(THREAD_LD) $(ZLIBLD)
-xzstd xzstd4 : CPPFLAGS += $(LZMACPP)
-xzstd xzstd4 : LDFLAGS += $(LZMALD)
-zstd4 xzstd4 : CPPFLAGS += $(LZ4CPP)
-zstd4 xzstd4 : LDFLAGS += $(LZ4LD)
-zstd zstd4 : LZMA_MSG := - xz/lzma support is disabled
-zstd xzstd : LZ4_MSG := - lz4 support is disabled
-zstd xzstd zstd4 xzstd4 : CPPFLAGS += -DZSTD_LEGACY_SUPPORT=$(ZSTD_LEGACY_SUPPORT)
-zstd xzstd zstd4 xzstd4 : $(ZSTDLIB_FILES) zstdcli.o fileio.o bench.o datagen.o dibio.o
+zstd zstd4 : CPPFLAGS += $(THREAD_CPP) $(ZLIBCPP) $(LZMACPP)
+zstd zstd4 : LDFLAGS += $(THREAD_LD) $(ZLIBLD) $(LZMALD)
+zstd4 : CPPFLAGS += $(LZ4CPP)
+zstd4 : LDFLAGS += $(LZ4LD)
+zstd : LZ4_MSG := - lz4 support is disabled
+zstd zstd4 : CPPFLAGS += -DZSTD_LEGACY_SUPPORT=$(ZSTD_LEGACY_SUPPORT)
+zstd zstd4 : $(ZSTDLIB_FILES) zstdcli.o fileio.o bench.o datagen.o dibio.o
 	@echo "$(THREAD_MSG)"
 	@echo "$(ZLIB_MSG)"
 	@echo "$(LZMA_MSG)"
@@ -179,6 +178,11 @@ zstd-nogz : ZLIBLD :=
 zstd-nogz : ZLIB_MSG := - gzip support is disabled
 zstd-nogz : zstd
 
+zstd-noxz : LZMACPP :=
+zstd-noxz : LZMALD :=
+zstd-noxz : LZMA_MSG := - xz/lzma support is disabled
+zstd-noxz : zstd
+
 
 zstd-pgo : MOREFLAGS = -fprofile-generate
 zstd-pgo : clean zstd
diff --git a/programs/README.md b/programs/README.md
index d7922a0969e4..bd8fba069952 100644
--- a/programs/README.md
+++ b/programs/README.md
@@ -24,13 +24,23 @@ There are however other Makefile targets that create different variations of CLI
 - __HAVE_ZLIB__ : `zstd` can compress and decompress files in `.gz` format.
   This is done through command `--format=gzip`.
   Alternatively, symlinks named `gzip` or `gunzip` will mimic intended behavior.
-  .gz support is automatically enabled when `zlib` library is detected at build time.
-  It's possible to disable .gz support, by either compiling `zstd-nogz` target or using HAVE_ZLIB=0 variable.
+  `.gz` support is automatically enabled when `zlib` library is detected at build time.
+  It's possible to disable `.gz` support, by either compiling `zstd-nogz` target or using HAVE_ZLIB=0 variable.
   Example : make zstd HAVE_ZLIB=0
   It's also possible to force compilation with zlib support, using HAVE_ZLIB=1.
   In which case, linking stage will fail if `zlib` library cannot be found.
   This might be useful to prevent silent feature disabling.
 
+- __HAVE_LZMA__ : `zstd` can compress and decompress files in `.xz` and `.lzma` formats.
+  This is done through commands `--format=xz` and `--format=lzma` respectively.
+  Alternatively, symlinks named `xz`, `unxz`, `lzma`, or `unlzma` will mimic intended behavior.
+  `.xz` and `.lzma` support is automatically enabled when `lzma` library is detected at build time.
+  It's possible to disable `.xz` and `.lzma` support, by either compiling `zstd-noxz` target or using HAVE_LZMA=0 variable.
+  Example : make zstd HAVE_LZMA=0
+  It's also possible to force compilation with lzma support, using HAVE_LZMA=1.
+  In which case, linking stage will fail if `lzma` library cannot be found.
+  This might be useful to prevent silent feature disabling.
+
 
 #### Aggregation of parameters
 CLI supports aggregation of parameters i.e. `-b1`, `-e18`, and `-i1` can be joined into `-b1e18i1`.
diff --git a/programs/bench.c b/programs/bench.c
index 22b871952b8e..f9493e3b0707 100644
--- a/programs/bench.c
+++ b/programs/bench.c
@@ -86,14 +86,13 @@ static clock_t g_time = 0;
 #ifndef DEBUG
 #  define DEBUG 0
 #endif
-#define DEBUGOUTPUT(...) if (DEBUG) DISPLAY(__VA_ARGS__);
-#define EXM_THROW(error, ...)                                             \
-{                                                                         \
-    DEBUGOUTPUT("%s: %i: \n", __FILE__, __LINE__); \
-    DISPLAYLEVEL(1, "Error %i : ", error);                                \
-    DISPLAYLEVEL(1, __VA_ARGS__);                                         \
-    DISPLAYLEVEL(1, " \n");                                               \
-    exit(error);                                                          \
+#define DEBUGOUTPUT(...) { if (DEBUG) DISPLAY(__VA_ARGS__); }
+#define EXM_THROW(error, ...)  {                      \
+    DEBUGOUTPUT("%s: %i: \n", __FILE__, __LINE__);    \
+    DISPLAYLEVEL(1, "Error %i : ", error);            \
+    DISPLAYLEVEL(1, __VA_ARGS__);                     \
+    DISPLAYLEVEL(1, " \n");                           \
+    exit(error);                                      \
 }
 
 
@@ -159,7 +158,6 @@ static int BMK_benchMem(const void* srcBuffer, size_t srcSize,
                         const ZSTD_compressionParameters* comprParams)
 {
     size_t const blockSize = ((g_blockSize>=32 && !g_decodeOnly) ? g_blockSize : srcSize) + (!srcSize) /* avoid div by 0 */ ;
-    size_t const avgSize = MIN(blockSize, (srcSize / nbFiles));
     U32 const maxNbBlocks = (U32) ((srcSize + (blockSize-1)) / blockSize) + nbFiles;
     blockParam_t* const blockTable = (blockParam_t*) malloc(maxNbBlocks * sizeof(blockParam_t));
     size_t const maxCompressedSize = ZSTD_compressBound(srcSize) + (maxNbBlocks * 1024);   /* add some room for safety */
@@ -262,42 +260,72 @@ static int BMK_benchMem(const void* srcBuffer, size_t srcSize,
                 UTIL_getTime(&clockStart);
 
                 if (!cCompleted) {   /* still some time to do compression tests */
-                    ZSTD_customMem const cmem = { NULL, NULL, NULL };
                     U64 const clockLoop = g_nbSeconds ? TIMELOOP_MICROSEC : 1;
                     U32 nbLoops = 0;
+                    ZSTD_CDict* cdict = NULL;
+#ifdef ZSTD_NEWAPI
+                    ZSTD_CCtx_setParameter(ctx, ZSTD_p_nbThreads, g_nbThreads);
+                    ZSTD_CCtx_setParameter(ctx, ZSTD_p_compressionLevel, cLevel);
+                    ZSTD_CCtx_setParameter(ctx, ZSTD_p_windowLog, comprParams->windowLog);
+                    ZSTD_CCtx_setParameter(ctx, ZSTD_p_chainLog, comprParams->chainLog);
+                    ZSTD_CCtx_setParameter(ctx, ZSTD_p_searchLog, comprParams->searchLog);
+                    ZSTD_CCtx_setParameter(ctx, ZSTD_p_minMatch, comprParams->searchLength);
+                    ZSTD_CCtx_setParameter(ctx, ZSTD_p_targetLength, comprParams->targetLength);
+                    ZSTD_CCtx_setParameter(ctx, ZSTD_p_compressionStrategy, comprParams->strategy);
+                    ZSTD_CCtx_loadDictionary(ctx, dictBuffer, dictBufferSize);
+#else
+                    size_t const avgSize = MIN(blockSize, (srcSize / nbFiles));
                     ZSTD_parameters zparams = ZSTD_getParams(cLevel, avgSize, dictBufferSize);
-                    ZSTD_CDict* cdict;
+                    ZSTD_customMem const cmem = { NULL, NULL, NULL };
                     if (comprParams->windowLog) zparams.cParams.windowLog = comprParams->windowLog;
                     if (comprParams->chainLog) zparams.cParams.chainLog = comprParams->chainLog;
                     if (comprParams->hashLog) zparams.cParams.hashLog = comprParams->hashLog;
                     if (comprParams->searchLog) zparams.cParams.searchLog = comprParams->searchLog;
                     if (comprParams->searchLength) zparams.cParams.searchLength = comprParams->searchLength;
                     if (comprParams->targetLength) zparams.cParams.targetLength = comprParams->targetLength;
-                    if (comprParams->strategy) zparams.cParams.strategy = (ZSTD_strategy)(comprParams->strategy - 1);
-                    cdict = ZSTD_createCDict_advanced(dictBuffer, dictBufferSize, 1, zparams.cParams, cmem);
+                    if (comprParams->strategy) zparams.cParams.strategy = comprParams->strategy;
+                    cdict = ZSTD_createCDict_advanced(dictBuffer, dictBufferSize, 1 /*byRef*/, ZSTD_dm_auto, zparams.cParams, cmem);
                     if (cdict==NULL) EXM_THROW(1, "ZSTD_createCDict_advanced() allocation failure");
+#endif
                     do {
                         U32 blockNb;
-                        size_t rSize;
                         for (blockNb=0; blockNb<nbBlocks; blockNb++) {
+                            size_t rSize;
+#ifdef ZSTD_NEWAPI
+                            ZSTD_outBuffer out = { blockTable[blockNb].cPtr,  blockTable[blockNb].cRoom, 0 };
+                            ZSTD_inBuffer in = { blockTable[blockNb].srcPtr,  blockTable[blockNb].srcSize, 0 };
+                            size_t cError = 1;
+                            while (cError) {
+                                cError = ZSTD_compress_generic(ctx,
+                                                    &out, &in, ZSTD_e_end);
+                                if (ZSTD_isError(cError))
+                                    EXM_THROW(1, "ZSTD_compress_generic() error : %s",
+                                                ZSTD_getErrorName(cError));
+                            }
+                            rSize = out.pos;
+#else  /* ! ZSTD_NEWAPI */
                             if (dictBufferSize) {
                                 rSize = ZSTD_compress_usingCDict(ctx,
                                                 blockTable[blockNb].cPtr,  blockTable[blockNb].cRoom,
                                                 blockTable[blockNb].srcPtr,blockTable[blockNb].srcSize,
                                                 cdict);
                             } else {
-#ifdef ZSTD_MULTITHREAD         /* note : limitation : MT single-pass does not support compression with dictionary */
+#  ifdef ZSTD_MULTITHREAD       /* note : limitation : MT single-pass does not support compression with dictionary */
                                 rSize = ZSTDMT_compressCCtx(mtctx,
                                                 blockTable[blockNb].cPtr,  blockTable[blockNb].cRoom,
                                                 blockTable[blockNb].srcPtr,blockTable[blockNb].srcSize,
                                                 cLevel);
-#else
+#  else
                                 rSize = ZSTD_compress_advanced (ctx,
                                                 blockTable[blockNb].cPtr,  blockTable[blockNb].cRoom,
-                                                blockTable[blockNb].srcPtr,blockTable[blockNb].srcSize, NULL, 0, zparams);
-#endif
+                                                blockTable[blockNb].srcPtr,blockTable[blockNb].srcSize,
+                                                NULL, 0, zparams);
+#  endif
                             }
-                            if (ZSTD_isError(rSize)) EXM_THROW(1, "ZSTD_compress_usingCDict() failed : %s", ZSTD_getErrorName(rSize));
+                            if (ZSTD_isError(rSize))
+                                EXM_THROW(1, "ZSTD_compress_usingCDict() failed : %s",
+                                            ZSTD_getErrorName(rSize));
+#endif  /* ZSTD_NEWAPI */
                             blockTable[blockNb].cSize = rSize;
                         }
                         nbLoops++;
@@ -383,7 +411,7 @@ static int BMK_benchMem(const void* srcBuffer, size_t srcSize,
                             }
                             pos = (U32)(u - bacc);
                             bNb = pos / (128 KB);
-                            DISPLAY("(block %u, sub %u, pos %u) \n", segNb, bNb, pos);
+                            DISPLAY("(sample %u, block %u, pos %u) \n", segNb, bNb, pos);
                             if (u>5) {
                                 int n;
                                 for (n=-5; n<0; n++) DISPLAY("%02X ", ((const BYTE*)srcBuffer)[u+n]);
diff --git a/programs/dibio.c b/programs/dibio.c
index aac36425cf75..31cde5c95db1 100644
--- a/programs/dibio.c
+++ b/programs/dibio.c
@@ -216,21 +216,21 @@ static U64 DiB_getTotalCappedFileSize(const char** fileNamesTable, unsigned nbFi
 }
 
 
-/*! ZDICT_trainFromBuffer_unsafe() :
+/*! ZDICT_trainFromBuffer_unsafe_legacy() :
     Strictly Internal use only !!
-    Same as ZDICT_trainFromBuffer_advanced(), but does not control `samplesBuffer`.
+    Same as ZDICT_trainFromBuffer_legacy(), but does not control `samplesBuffer`.
     `samplesBuffer` must be followed by noisy guard band to avoid out-of-buffer reads.
     @return : size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
               or an error code.
 */
-size_t ZDICT_trainFromBuffer_unsafe(void* dictBuffer, size_t dictBufferCapacity,
-                              const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
-                              ZDICT_params_t parameters);
+size_t ZDICT_trainFromBuffer_unsafe_legacy(void* dictBuffer, size_t dictBufferCapacity,
+                                           const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
+                                           ZDICT_legacy_params_t parameters);
 
 
 int DiB_trainFromFiles(const char* dictFileName, unsigned maxDictSize,
                        const char** fileNamesTable, unsigned nbFiles,
-                       ZDICT_params_t *params, COVER_params_t *coverParams,
+                       ZDICT_legacy_params_t *params, ZDICT_cover_params_t *coverParams,
                        int optimizeCover)
 {
     void* const dictBuffer = malloc(maxDictSize);
@@ -243,8 +243,8 @@ int DiB_trainFromFiles(const char* dictFileName, unsigned maxDictSize,
     int result = 0;
 
     /* Checks */
-    if (params) g_displayLevel = params->notificationLevel;
-    else if (coverParams) g_displayLevel = coverParams->notificationLevel;
+    if (params) g_displayLevel = params->zParams.notificationLevel;
+    else if (coverParams) g_displayLevel = coverParams->zParams.notificationLevel;
     else EXM_THROW(13, "Neither dictionary algorith selected");   /* should not happen */
     if ((!fileSizes) || (!srcBuffer) || (!dictBuffer)) EXM_THROW(12, "not enough memory for DiB_trainFiles");   /* should not happen */
     if (g_tooLargeSamples) {
@@ -273,20 +273,20 @@ int DiB_trainFromFiles(const char* dictFileName, unsigned maxDictSize,
         size_t dictSize;
         if (params) {
             DiB_fillNoise((char*)srcBuffer + benchedSize, NOISELENGTH);   /* guard band, for end of buffer condition */
-            dictSize = ZDICT_trainFromBuffer_unsafe(dictBuffer, maxDictSize,
-                                                    srcBuffer, fileSizes, nbFiles,
-                                                    *params);
+            dictSize = ZDICT_trainFromBuffer_unsafe_legacy(dictBuffer, maxDictSize,
+                                                           srcBuffer, fileSizes, nbFiles,
+                                                           *params);
         } else if (optimizeCover) {
-            dictSize = COVER_optimizeTrainFromBuffer(
-                dictBuffer, maxDictSize, srcBuffer, fileSizes, nbFiles,
-                coverParams);
+            dictSize = ZDICT_optimizeTrainFromBuffer_cover(dictBuffer, maxDictSize,
+                                                           srcBuffer, fileSizes, nbFiles,
+                                                           coverParams);
             if (!ZDICT_isError(dictSize)) {
-              DISPLAYLEVEL(2, "k=%u\nd=%u\nsteps=%u\n", coverParams->k, coverParams->d, coverParams->steps);
+                DISPLAYLEVEL(2, "k=%u\nd=%u\nsteps=%u\n", coverParams->k, coverParams->d, coverParams->steps);
             }
         } else {
-            dictSize = COVER_trainFromBuffer(dictBuffer, maxDictSize,
-                                             srcBuffer, fileSizes, nbFiles,
-                                             *coverParams);
+            dictSize =
+                ZDICT_trainFromBuffer_cover(dictBuffer, maxDictSize, srcBuffer,
+                                            fileSizes, nbFiles, *coverParams);
         }
         if (ZDICT_isError(dictSize)) {
             DISPLAYLEVEL(1, "dictionary training failed : %s \n", ZDICT_getErrorName(dictSize));   /* should not happen */
diff --git a/programs/dibio.h b/programs/dibio.h
index e61d0042c850..84f7d580283d 100644
--- a/programs/dibio.h
+++ b/programs/dibio.h
@@ -32,7 +32,7 @@
 */
 int DiB_trainFromFiles(const char* dictFileName, unsigned maxDictSize,
                        const char** fileNamesTable, unsigned nbFiles,
-                       ZDICT_params_t *params, COVER_params_t *coverParams,
+                       ZDICT_legacy_params_t *params, ZDICT_cover_params_t *coverParams,
                        int optimizeCover);
 
 #endif
diff --git a/programs/fileio.c b/programs/fileio.c
index e188936b21f5..1dd8008e8495 100644
--- a/programs/fileio.c
+++ b/programs/fileio.c
@@ -77,10 +77,7 @@
 #define BLOCKSIZE      (128 KB)
 #define ROLLBUFFERSIZE (BLOCKSIZE*8*64)
 
-#define FIO_FRAMEHEADERSIZE  5        /* as a define, because needed to allocated table on stack */
-#define FSE_CHECKSUM_SEED    0
-
-#define CACHELINE 64
+#define FIO_FRAMEHEADERSIZE  5    /* as a define, because needed to allocated table on stack */
 
 #define DICTSIZE_MAX (32 MB)   /* protection against large input (attack scenario) */
 
@@ -91,8 +88,9 @@
 *  Macros
 ***************************************/
 #define DISPLAY(...)         fprintf(stderr, __VA_ARGS__)
+#define DISPLAYOUT(...)      fprintf(stdout, __VA_ARGS__)
 #define DISPLAYLEVEL(l, ...) { if (g_displayLevel>=l) { DISPLAY(__VA_ARGS__); } }
-static int g_displayLevel = 2;   /* 0 : no display;   1: errors;   2 : + result + interaction + warnings;   3 : + progression;   4 : + information */
+static int g_displayLevel = 2;   /* 0 : no display;  1: errors;  2: + result + interaction + warnings;  3: + progression;  4: + information */
 void FIO_setNotificationLevel(unsigned level) { g_displayLevel=level; }
 
 #define DISPLAYUPDATE(l, ...) { if (g_displayLevel>=l) { \
@@ -102,10 +100,46 @@ void FIO_setNotificationLevel(unsigned level) { g_displayLevel=level; }
 static const clock_t refreshRate = CLOCKS_PER_SEC * 15 / 100;
 static clock_t g_time = 0;
 
-#undef MIN
+#undef MIN  /* in case it would be already defined */
 #define MIN(a,b)    ((a) < (b) ? (a) : (b))
 
 
+/*-*************************************
+*  Errors
+***************************************/
+/*-*************************************
+*  Debug
+***************************************/
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
+#  include <assert.h>
+#else
+#  ifndef assert
+#    define assert(condition) ((void)0)
+#  endif
+#endif
+
+#ifndef ZSTD_DEBUG
+#  define ZSTD_DEBUG 0
+#endif
+#define DEBUGLOG(l,...) if (l<=ZSTD_DEBUG) DISPLAY(__VA_ARGS__);
+#define EXM_THROW(error, ...)                                              \
+{                                                                          \
+    DISPLAYLEVEL(1, "zstd: ");                                             \
+    DEBUGLOG(1, "Error defined at %s, line %i : \n", __FILE__, __LINE__);  \
+    DISPLAYLEVEL(1, "error %i : ", error);                                 \
+    DISPLAYLEVEL(1, __VA_ARGS__);                                          \
+    DISPLAYLEVEL(1, " \n");                                                \
+    exit(error);                                                           \
+}
+
+#define CHECK(f) {                                   \
+    size_t const err = f;                            \
+    if (ZSTD_isError(err)) {                         \
+        DEBUGLOG(1, "%s \n", #f);                    \
+        EXM_THROW(11, "%s", ZSTD_getErrorName(err)); \
+}   }
+
+
 /* ************************************************************
 * Avoid fseek()'s 2GiB barrier with MSVC, MacOS, *BSD, MinGW
 ***************************************************************/
@@ -145,7 +179,7 @@ static FIO_compressionType_t g_compressionType = FIO_zstdCompression;
 void FIO_setCompressionType(FIO_compressionType_t compressionType) { g_compressionType = compressionType; }
 static U32 g_overwrite = 0;
 void FIO_overwriteMode(void) { g_overwrite=1; }
-static U32 g_sparseFileSupport = 1;   /* 0 : no sparse allowed; 1: auto (file yes, stdout no); 2: force sparse */
+static U32 g_sparseFileSupport = 1;   /* 0: no sparse allowed; 1: auto (file yes, stdout no); 2: force sparse */
 void FIO_setSparseWrite(unsigned sparse) { g_sparseFileSupport=sparse; }
 static U32 g_dictIDFlag = 1;
 void FIO_setDictIDFlag(unsigned dictIDFlag) { g_dictIDFlag = dictIDFlag; }
@@ -182,23 +216,6 @@ void FIO_setOverlapLog(unsigned overlapLog){
 
 
 /*-*************************************
-*  Exceptions
-***************************************/
-#ifndef DEBUG
-#  define DEBUG 0
-#endif
-#define DEBUGOUTPUT(...) if (DEBUG) DISPLAY(__VA_ARGS__);
-#define EXM_THROW(error, ...)                                             \
-{                                                                         \
-    DEBUGOUTPUT("Error defined at %s, line %i : \n", __FILE__, __LINE__); \
-    DISPLAYLEVEL(1, "Error %i : ", error);                                \
-    DISPLAYLEVEL(1, __VA_ARGS__);                                         \
-    DISPLAYLEVEL(1, " \n");                                               \
-    exit(error);                                                          \
-}
-
-
-/*-*************************************
 *  Functions
 ***************************************/
 /** FIO_remove() :
@@ -206,8 +223,8 @@ void FIO_setOverlapLog(unsigned overlapLog){
 static int FIO_remove(const char* path)
 {
 #if defined(_WIN32) || defined(WIN32)
-    /* windows doesn't allow remove read-only files, so try to make it
-     * writable first */
+    /* windows doesn't allow remove read-only files,
+     * so try to make it writable first */
     chmod(path, _S_IWRITE);
 #endif
     return remove(path);
@@ -225,12 +242,14 @@ static FILE* FIO_openSrcFile(const char* srcFileName)
         f = stdin;
         SET_BINARY_MODE(stdin);
     } else {
-        if (!UTIL_isRegFile(srcFileName)) {
-            DISPLAYLEVEL(1, "zstd: %s is not a regular file -- ignored \n", srcFileName);
+        if (!UTIL_isRegularFile(srcFileName)) {
+            DISPLAYLEVEL(1, "zstd: %s is not a regular file -- ignored \n",
+                            srcFileName);
             return NULL;
         }
         f = fopen(srcFileName, "rb");
-        if ( f==NULL ) DISPLAYLEVEL(1, "zstd: %s: %s \n", srcFileName, strerror(errno));
+        if ( f==NULL )
+            DISPLAYLEVEL(1, "zstd: %s: %s \n", srcFileName, strerror(errno));
     }
 
     return f;
@@ -255,26 +274,28 @@ static FILE* FIO_openDstFile(const char* dstFileName)
         if (g_sparseFileSupport == 1) {
             g_sparseFileSupport = ZSTD_SPARSE_DEFAULT;
         }
-        if (strcmp (dstFileName, nulmark)) {  /* Check if destination file already exists */
+        if (strcmp (dstFileName, nulmark)) {
+            /* Check if destination file already exists */
             f = fopen( dstFileName, "rb" );
-            if (f != 0) {  /* dest file exists, prompt for overwrite authorization */
+            if (f != 0) {  /* dst file exists, prompt for overwrite authorization */
                 fclose(f);
                 if (!g_overwrite) {
                     if (g_displayLevel <= 1) {
                         /* No interaction possible */
-                        DISPLAY("zstd: %s already exists; not overwritten  \n", dstFileName);
+                        DISPLAY("zstd: %s already exists; not overwritten  \n",
+                                dstFileName);
                         return NULL;
                     }
-                    DISPLAY("zstd: %s already exists; do you wish to overwrite (y/N) ? ", dstFileName);
+                    DISPLAY("zstd: %s already exists; do you wish to overwrite (y/N) ? ",
+                            dstFileName);
                     {   int ch = getchar();
                         if ((ch!='Y') && (ch!='y')) {
                             DISPLAY("    not overwritten  \n");
                             return NULL;
                         }
-                        while ((ch!=EOF) && (ch!='\n')) ch = getchar();  /* flush rest of input line */
-                    }
-                }
-
+                        /* flush rest of input line */
+                        while ((ch!=EOF) && (ch!='\n')) ch = getchar();
+                }   }
                 /* need to unlink */
                 FIO_remove(dstFileName);
         }   }
@@ -302,11 +323,13 @@ static size_t FIO_createDictBuffer(void** bufferPtr, const char* fileName)
 
     DISPLAYLEVEL(4,"Loading %s as dictionary \n", fileName);
     fileHandle = fopen(fileName, "rb");
-    if (fileHandle==0) EXM_THROW(31, "zstd: %s: %s", fileName, strerror(errno));
+    if (fileHandle==0) EXM_THROW(31, "%s: %s", fileName, strerror(errno));
     fileSize = UTIL_getFileSize(fileName);
-    if (fileSize > DICTSIZE_MAX) EXM_THROW(32, "Dictionary file %s is too large (> %u MB)", fileName, DICTSIZE_MAX >> 20);   /* avoid extreme cases */
+    if (fileSize > DICTSIZE_MAX)
+        EXM_THROW(32, "Dictionary file %s is too large (> %u MB)",
+                        fileName, DICTSIZE_MAX >> 20);   /* avoid extreme cases */
     *bufferPtr = malloc((size_t)fileSize);
-    if (*bufferPtr==NULL) EXM_THROW(34, "zstd: %s", strerror(errno));
+    if (*bufferPtr==NULL) EXM_THROW(34, "%s", strerror(errno));
     { size_t const readSize = fread(*bufferPtr, 1, (size_t)fileSize, fileHandle);
       if (readSize!=fileSize) EXM_THROW(35, "Error reading dictionary file %s", fileName); }
     fclose(fileHandle);
@@ -325,7 +348,7 @@ typedef struct {
     size_t srcBufferSize;
     void*  dstBuffer;
     size_t dstBufferSize;
-#ifdef ZSTD_MULTITHREAD
+#if !defined(ZSTD_NEWAPI) && defined(ZSTD_MULTITHREAD)
     ZSTDMT_CCtx* cctx;
 #else
     ZSTD_CStream* cctx;
@@ -333,34 +356,65 @@ typedef struct {
 } cRess_t;
 
 static cRess_t FIO_createCResources(const char* dictFileName, int cLevel,
-                                    U64 srcSize, int srcRegFile,
+                                    U64 srcSize, int srcIsRegularFile,
                                     ZSTD_compressionParameters* comprParams) {
     cRess_t ress;
     memset(&ress, 0, sizeof(ress));
 
-#ifdef ZSTD_MULTITHREAD
+#ifdef ZSTD_NEWAPI
+    ress.cctx = ZSTD_createCCtx();
+    if (ress.cctx == NULL)
+        EXM_THROW(30, "allocation error : can't create ZSTD_CCtx");
+#elif defined(ZSTD_MULTITHREAD)
     ress.cctx = ZSTDMT_createCCtx(g_nbThreads);
-    if (ress.cctx == NULL) EXM_THROW(30, "zstd: allocation error : can't create ZSTD_CStream");
+    if (ress.cctx == NULL)
+        EXM_THROW(30, "allocation error : can't create ZSTDMT_CCtx");
     if ((cLevel==ZSTD_maxCLevel()) && (g_overlapLog==FIO_OVERLAP_LOG_NOTSET))
-        ZSTDMT_setMTCtxParameter(ress.cctx, ZSTDMT_p_overlapSectionLog, 9);   /* use complete window for overlap */
+        /* use complete window for overlap */
+        ZSTDMT_setMTCtxParameter(ress.cctx, ZSTDMT_p_overlapSectionLog, 9);
     if (g_overlapLog != FIO_OVERLAP_LOG_NOTSET)
         ZSTDMT_setMTCtxParameter(ress.cctx, ZSTDMT_p_overlapSectionLog, g_overlapLog);
 #else
     ress.cctx = ZSTD_createCStream();
-    if (ress.cctx == NULL) EXM_THROW(30, "zstd: allocation error : can't create ZSTD_CStream");
+    if (ress.cctx == NULL)
+        EXM_THROW(30, "allocation error : can't create ZSTD_CStream");
 #endif
     ress.srcBufferSize = ZSTD_CStreamInSize();
     ress.srcBuffer = malloc(ress.srcBufferSize);
     ress.dstBufferSize = ZSTD_CStreamOutSize();
     ress.dstBuffer = malloc(ress.dstBufferSize);
-    if (!ress.srcBuffer || !ress.dstBuffer) EXM_THROW(31, "zstd: allocation error : not enough memory");
+    if (!ress.srcBuffer || !ress.dstBuffer)
+        EXM_THROW(31, "allocation error : not enough memory");
 
     /* dictionary */
     {   void* dictBuffer;
         size_t const dictBuffSize = FIO_createDictBuffer(&dictBuffer, dictFileName);   /* works with dictFileName==NULL */
-        if (dictFileName && (dictBuffer==NULL)) EXM_THROW(32, "zstd: allocation error : can't create dictBuffer");
+        if (dictFileName && (dictBuffer==NULL))
+            EXM_THROW(32, "allocation error : can't create dictBuffer");
+
+#ifdef ZSTD_NEWAPI
+        {   /* frame parameters */
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_contentSizeFlag, srcIsRegularFile) );
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_dictIDFlag, g_dictIDFlag) );
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_checksumFlag, g_checksumFlag) );
+            CHECK( ZSTD_CCtx_setPledgedSrcSize(ress.cctx, srcSize) );
+            /* compression parameters */
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_compressionLevel, cLevel) );
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_windowLog, comprParams->windowLog) );
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_chainLog, comprParams->chainLog) );
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_hashLog, comprParams->hashLog) );
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_searchLog, comprParams->searchLog) );
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_minMatch, comprParams->searchLength) );
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_targetLength, comprParams->targetLength) );
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_compressionStrategy, (U32)comprParams->strategy) );
+            /* multi-threading */
+            CHECK( ZSTD_CCtx_setParameter(ress.cctx, ZSTD_p_nbThreads, g_nbThreads) );
+            /* dictionary */
+            CHECK( ZSTD_CCtx_loadDictionary(ress.cctx, dictBuffer, dictBuffSize) );
+        }
+#elif defined(ZSTD_MULTITHREAD)
         {   ZSTD_parameters params = ZSTD_getParams(cLevel, srcSize, dictBuffSize);
-            params.fParams.contentSizeFlag = srcRegFile;
+            params.fParams.contentSizeFlag = srcIsRegularFile;
             params.fParams.checksumFlag = g_checksumFlag;
             params.fParams.noDictIDFlag = !g_dictIDFlag;
             if (comprParams->windowLog) params.cParams.windowLog = comprParams->windowLog;
@@ -369,16 +423,25 @@ static cRess_t FIO_createCResources(const char* dictFileName, int cLevel,
             if (comprParams->searchLog) params.cParams.searchLog = comprParams->searchLog;
             if (comprParams->searchLength) params.cParams.searchLength = comprParams->searchLength;
             if (comprParams->targetLength) params.cParams.targetLength = comprParams->targetLength;
-            if (comprParams->strategy) params.cParams.strategy = (ZSTD_strategy)(comprParams->strategy - 1);   /* 0 means : do not change */
-#ifdef ZSTD_MULTITHREAD
-            {   size_t const errorCode = ZSTDMT_initCStream_advanced(ress.cctx, dictBuffer, dictBuffSize, params, srcSize);
-                if (ZSTD_isError(errorCode)) EXM_THROW(33, "Error initializing CStream : %s", ZSTD_getErrorName(errorCode));
-                ZSTDMT_setMTCtxParameter(ress.cctx, ZSTDMT_p_sectionSize, g_blockSize);
+            if (comprParams->strategy) params.cParams.strategy = (ZSTD_strategy) comprParams->strategy;
+            CHECK( ZSTDMT_initCStream_advanced(ress.cctx, dictBuffer, dictBuffSize, params, srcSize) );
+            ZSTDMT_setMTCtxParameter(ress.cctx, ZSTDMT_p_sectionSize, g_blockSize);
+        }
 #else
-            {   size_t const errorCode = ZSTD_initCStream_advanced(ress.cctx, dictBuffer, dictBuffSize, params, srcSize);
-                if (ZSTD_isError(errorCode)) EXM_THROW(33, "Error initializing CStream : %s", ZSTD_getErrorName(errorCode));
+        {   ZSTD_parameters params = ZSTD_getParams(cLevel, srcSize, dictBuffSize);
+            params.fParams.contentSizeFlag = srcIsRegularFile;
+            params.fParams.checksumFlag = g_checksumFlag;
+            params.fParams.noDictIDFlag = !g_dictIDFlag;
+            if (comprParams->windowLog) params.cParams.windowLog = comprParams->windowLog;
+            if (comprParams->chainLog) params.cParams.chainLog = comprParams->chainLog;
+            if (comprParams->hashLog) params.cParams.hashLog = comprParams->hashLog;
+            if (comprParams->searchLog) params.cParams.searchLog = comprParams->searchLog;
+            if (comprParams->searchLength) params.cParams.searchLength = comprParams->searchLength;
+            if (comprParams->targetLength) params.cParams.targetLength = comprParams->targetLength;
+            if (comprParams->strategy) params.cParams.strategy = (ZSTD_strategy) comprParams->strategy;
+            CHECK( ZSTD_initCStream_advanced(ress.cctx, dictBuffer, dictBuffSize, params, srcSize) );
+        }
 #endif
-        }   }
         free(dictBuffer);
     }
 
@@ -389,7 +452,7 @@ static void FIO_freeCResources(cRess_t ress)
 {
     free(ress.srcBuffer);
     free(ress.dstBuffer);
-#ifdef ZSTD_MULTITHREAD
+#if !defined(ZSTD_NEWAPI) && defined(ZSTD_MULTITHREAD)
     ZSTDMT_freeCCtx(ress.cctx);
 #else
     ZSTD_freeCStream(ress.cctx);   /* never fails */
@@ -398,20 +461,26 @@ static void FIO_freeCResources(cRess_t ress)
 
 
 #ifdef ZSTD_GZCOMPRESS
-static unsigned long long FIO_compressGzFrame(cRess_t* ress, const char* srcFileName, U64 const srcFileSize, int compressionLevel, U64* readsize)
+static unsigned long long FIO_compressGzFrame(cRess_t* ress,
+                    const char* srcFileName, U64 const srcFileSize,
+                    int compressionLevel, U64* readsize)
 {
     unsigned long long inFileSize = 0, outFileSize = 0;
     z_stream strm;
     int ret;
 
-    if (compressionLevel > Z_BEST_COMPRESSION) compressionLevel = Z_BEST_COMPRESSION;
+    if (compressionLevel > Z_BEST_COMPRESSION)
+        compressionLevel = Z_BEST_COMPRESSION;
 
     strm.zalloc = Z_NULL;
     strm.zfree = Z_NULL;
     strm.opaque = Z_NULL;
 
-    ret = deflateInit2(&strm, compressionLevel, Z_DEFLATED, 15 /* maxWindowLogSize */ + 16 /* gzip only */, 8, Z_DEFAULT_STRATEGY); /* see http://www.zlib.net/manual.html */
-    if (ret != Z_OK) EXM_THROW(71, "zstd: %s: deflateInit2 error %d \n", srcFileName, ret);
+    ret = deflateInit2(&strm, compressionLevel, Z_DEFLATED,
+                        15 /* maxWindowLogSize */ + 16 /* gzip only */,
+                        8, Z_DEFAULT_STRATEGY); /* see http://www.zlib.net/manual.html */
+    if (ret != Z_OK)
+        EXM_THROW(71, "zstd: %s: deflateInit2 error %d \n", srcFileName, ret);
 
     strm.next_in = 0;
     strm.avail_in = 0;
@@ -427,35 +496,45 @@ static unsigned long long FIO_compressGzFrame(cRess_t* ress, const char* srcFile
             strm.avail_in = (uInt)inSize;
         }
         ret = deflate(&strm, Z_NO_FLUSH);
-        if (ret != Z_OK) EXM_THROW(72, "zstd: %s: deflate error %d \n", srcFileName, ret);
+        if (ret != Z_OK)
+            EXM_THROW(72, "zstd: %s: deflate error %d \n", srcFileName, ret);
         {   size_t const decompBytes = ress->dstBufferSize - strm.avail_out;
             if (decompBytes) {
-                if (fwrite(ress->dstBuffer, 1, decompBytes, ress->dstFile) != decompBytes) EXM_THROW(73, "Write error : cannot write to output file");
+                if (fwrite(ress->dstBuffer, 1, decompBytes, ress->dstFile) != decompBytes)
+                    EXM_THROW(73, "Write error : cannot write to output file");
                 outFileSize += decompBytes;
                 strm.next_out = (Bytef*)ress->dstBuffer;
                 strm.avail_out = (uInt)ress->dstBufferSize;
             }
         }
-        if (!srcFileSize) DISPLAYUPDATE(2, "\rRead : %u MB ==> %.2f%%", (U32)(inFileSize>>20), (double)outFileSize/inFileSize*100)
-        else DISPLAYUPDATE(2, "\rRead : %u / %u MB ==> %.2f%%", (U32)(inFileSize>>20), (U32)(srcFileSize>>20), (double)outFileSize/inFileSize*100);
+        if (!srcFileSize)
+            DISPLAYUPDATE(2, "\rRead : %u MB ==> %.2f%%",
+                            (U32)(inFileSize>>20),
+                            (double)outFileSize/inFileSize*100)
+        else
+            DISPLAYUPDATE(2, "\rRead : %u / %u MB ==> %.2f%%",
+                            (U32)(inFileSize>>20), (U32)(srcFileSize>>20),
+                            (double)outFileSize/inFileSize*100);
     }
 
     while (1) {
         ret = deflate(&strm, Z_FINISH);
         {   size_t const decompBytes = ress->dstBufferSize - strm.avail_out;
             if (decompBytes) {
-                if (fwrite(ress->dstBuffer, 1, decompBytes, ress->dstFile) != decompBytes) EXM_THROW(75, "Write error : cannot write to output file");
+                if (fwrite(ress->dstBuffer, 1, decompBytes, ress->dstFile) != decompBytes)
+                    EXM_THROW(75, "Write error : cannot write to output file");
                 outFileSize += decompBytes;
                 strm.next_out = (Bytef*)ress->dstBuffer;
                 strm.avail_out = (uInt)ress->dstBufferSize;
-            }
-        }
+        }   }
         if (ret == Z_STREAM_END) break;
-        if (ret != Z_BUF_ERROR) EXM_THROW(77, "zstd: %s: deflate error %d \n", srcFileName, ret);
+        if (ret != Z_BUF_ERROR)
+            EXM_THROW(77, "zstd: %s: deflate error %d \n", srcFileName, ret);
     }
 
     ret = deflateEnd(&strm);
-    if (ret != Z_OK) EXM_THROW(79, "zstd: %s: deflateEnd error %d \n", srcFileName, ret);
+    if (ret != Z_OK)
+        EXM_THROW(79, "zstd: %s: deflateEnd error %d \n", srcFileName, ret);
     *readsize = inFileSize;
 
     return outFileSize;
@@ -464,7 +543,9 @@ static unsigned long long FIO_compressGzFrame(cRess_t* ress, const char* srcFile
 
 
 #ifdef ZSTD_LZMACOMPRESS
-static unsigned long long FIO_compressLzmaFrame(cRess_t* ress, const char* srcFileName, U64 const srcFileSize, int compressionLevel, U64* readsize, int plain_lzma)
+static unsigned long long FIO_compressLzmaFrame(cRess_t* ress,
+                            const char* srcFileName, U64 const srcFileSize,
+                            int compressionLevel, U64* readsize, int plain_lzma)
 {
     unsigned long long inFileSize = 0, outFileSize = 0;
     lzma_stream strm = LZMA_STREAM_INIT;
@@ -476,17 +557,20 @@ static unsigned long long FIO_compressLzmaFrame(cRess_t* ress, const char* srcFi
 
     if (plain_lzma) {
         lzma_options_lzma opt_lzma;
-        if (lzma_lzma_preset(&opt_lzma, compressionLevel)) EXM_THROW(71, "zstd: %s: lzma_lzma_preset error", srcFileName);
+        if (lzma_lzma_preset(&opt_lzma, compressionLevel))
+            EXM_THROW(71, "zstd: %s: lzma_lzma_preset error", srcFileName);
         ret = lzma_alone_encoder(&strm, &opt_lzma); /* LZMA */
-        if (ret != LZMA_OK) EXM_THROW(71, "zstd: %s: lzma_alone_encoder error %d", srcFileName, ret);
+        if (ret != LZMA_OK)
+            EXM_THROW(71, "zstd: %s: lzma_alone_encoder error %d", srcFileName, ret);
     } else {
         ret = lzma_easy_encoder(&strm, compressionLevel, LZMA_CHECK_CRC64); /* XZ */
-        if (ret != LZMA_OK) EXM_THROW(71, "zstd: %s: lzma_easy_encoder error %d", srcFileName, ret);
+        if (ret != LZMA_OK)
+            EXM_THROW(71, "zstd: %s: lzma_easy_encoder error %d", srcFileName, ret);
     }
 
     strm.next_in = 0;
     strm.avail_in = 0;
-    strm.next_out = ress->dstBuffer;
+    strm.next_out = (BYTE*)ress->dstBuffer;
     strm.avail_out = ress->dstBufferSize;
 
     while (1) {
@@ -494,23 +578,30 @@ static unsigned long long FIO_compressLzmaFrame(cRess_t* ress, const char* srcFi
             size_t const inSize = fread(ress->srcBuffer, 1, ress->srcBufferSize, ress->srcFile);
             if (inSize == 0) action = LZMA_FINISH;
             inFileSize += inSize;
-            strm.next_in = ress->srcBuffer;
+            strm.next_in = (BYTE const*)ress->srcBuffer;
             strm.avail_in = inSize;
         }
 
         ret = lzma_code(&strm, action);
 
-        if (ret != LZMA_OK && ret != LZMA_STREAM_END) EXM_THROW(72, "zstd: %s: lzma_code encoding error %d", srcFileName, ret);
+        if (ret != LZMA_OK && ret != LZMA_STREAM_END)
+            EXM_THROW(72, "zstd: %s: lzma_code encoding error %d", srcFileName, ret);
         {   size_t const compBytes = ress->dstBufferSize - strm.avail_out;
             if (compBytes) {
-                if (fwrite(ress->dstBuffer, 1, compBytes, ress->dstFile) != compBytes) EXM_THROW(73, "Write error : cannot write to output file");
+                if (fwrite(ress->dstBuffer, 1, compBytes, ress->dstFile) != compBytes)
+                    EXM_THROW(73, "Write error : cannot write to output file");
                 outFileSize += compBytes;
-                strm.next_out = ress->dstBuffer;
+                strm.next_out = (BYTE*)ress->dstBuffer;
                 strm.avail_out = ress->dstBufferSize;
-            }
-        }
-        if (!srcFileSize) DISPLAYUPDATE(2, "\rRead : %u MB ==> %.2f%%", (U32)(inFileSize>>20), (double)outFileSize/inFileSize*100)
-        else DISPLAYUPDATE(2, "\rRead : %u / %u MB ==> %.2f%%", (U32)(inFileSize>>20), (U32)(srcFileSize>>20), (double)outFileSize/inFileSize*100);
+        }   }
+        if (!srcFileSize)
+            DISPLAYUPDATE(2, "\rRead : %u MB ==> %.2f%%",
+                            (U32)(inFileSize>>20),
+                            (double)outFileSize/inFileSize*100)
+        else
+            DISPLAYUPDATE(2, "\rRead : %u / %u MB ==> %.2f%%",
+                            (U32)(inFileSize>>20), (U32)(srcFileSize>>20),
+                            (double)outFileSize/inFileSize*100);
         if (ret == LZMA_STREAM_END) break;
     }
 
@@ -523,7 +614,9 @@ static unsigned long long FIO_compressLzmaFrame(cRess_t* ress, const char* srcFi
 
 #ifdef ZSTD_LZ4COMPRESS
 static int FIO_LZ4_GetBlockSize_FromBlockId (int id) { return (1 << (8 + (2 * id))); }
-static unsigned long long FIO_compressLz4Frame(cRess_t* ress, const char* srcFileName, U64 const srcFileSize, int compressionLevel, U64* readsize)
+static unsigned long long FIO_compressLz4Frame(cRess_t* ress,
+                            const char* srcFileName, U64 const srcFileSize,
+                            int compressionLevel, U64* readsize)
 {
     unsigned long long inFileSize = 0, outFileSize = 0;
 
@@ -531,7 +624,8 @@ static unsigned long long FIO_compressLz4Frame(cRess_t* ress, const char* srcFil
     LZ4F_compressionContext_t ctx;
 
     LZ4F_errorCode_t const errorCode = LZ4F_createCompressionContext(&ctx, LZ4F_VERSION);
-    if (LZ4F_isError(errorCode)) EXM_THROW(31, "zstd: failed to create lz4 compression context");
+    if (LZ4F_isError(errorCode))
+        EXM_THROW(31, "zstd: failed to create lz4 compression context");
 
     memset(&prefs, 0, sizeof(prefs));
 
@@ -553,7 +647,9 @@ static unsigned long long FIO_compressLz4Frame(cRess_t* ress, const char* srcFil
         size_t blockSize = FIO_LZ4_GetBlockSize_FromBlockId(LZ4F_max4MB);
         size_t readSize;
         size_t headerSize = LZ4F_compressBegin(ctx, ress->dstBuffer, ress->dstBufferSize, &prefs);
-        if (LZ4F_isError(headerSize)) EXM_THROW(33, "File header generation failed : %s", LZ4F_getErrorName(headerSize));
+        if (LZ4F_isError(headerSize))
+            EXM_THROW(33, "File header generation failed : %s",
+                            LZ4F_getErrorName(headerSize));
         { size_t const sizeCheck = fwrite(ress->dstBuffer, 1, headerSize, ress->dstFile);
           if (sizeCheck!=headerSize) EXM_THROW(34, "Write error : cannot write header"); }
         outFileSize += headerSize;
@@ -568,10 +664,18 @@ static unsigned long long FIO_compressLz4Frame(cRess_t* ress, const char* srcFil
 
             /* Compress Block */
             outSize = LZ4F_compressUpdate(ctx, ress->dstBuffer, ress->dstBufferSize, ress->srcBuffer, readSize, NULL);
-            if (LZ4F_isError(outSize)) EXM_THROW(35, "zstd: %s: lz4 compression failed : %s", srcFileName, LZ4F_getErrorName(outSize));
+            if (LZ4F_isError(outSize))
+                EXM_THROW(35, "zstd: %s: lz4 compression failed : %s",
+                            srcFileName, LZ4F_getErrorName(outSize));
             outFileSize += outSize;
-            if (!srcFileSize) DISPLAYUPDATE(2, "\rRead : %u MB ==> %.2f%%", (U32)(inFileSize>>20), (double)outFileSize/inFileSize*100)
-            else DISPLAYUPDATE(2, "\rRead : %u / %u MB ==> %.2f%%", (U32)(inFileSize>>20), (U32)(srcFileSize>>20), (double)outFileSize/inFileSize*100);
+            if (!srcFileSize)
+                DISPLAYUPDATE(2, "\rRead : %u MB ==> %.2f%%",
+                                (U32)(inFileSize>>20),
+                                (double)outFileSize/inFileSize*100)
+            else
+                DISPLAYUPDATE(2, "\rRead : %u / %u MB ==> %.2f%%",
+                                (U32)(inFileSize>>20), (U32)(srcFileSize>>20),
+                                (double)outFileSize/inFileSize*100);
 
             /* Write Block */
             { size_t const sizeCheck = fwrite(ress->dstBuffer, 1, outSize, ress->dstFile);
@@ -585,7 +689,9 @@ static unsigned long long FIO_compressLz4Frame(cRess_t* ress, const char* srcFil
 
         /* End of Stream mark */
         headerSize = LZ4F_compressEnd(ctx, ress->dstBuffer, ress->dstBufferSize, NULL);
-        if (LZ4F_isError(headerSize)) EXM_THROW(38, "zstd: %s: lz4 end of file generation failed : %s", srcFileName, LZ4F_getErrorName(headerSize));
+        if (LZ4F_isError(headerSize))
+            EXM_THROW(38, "zstd: %s: lz4 end of file generation failed : %s",
+                        srcFileName, LZ4F_getErrorName(headerSize));
 
         { size_t const sizeCheck = fwrite(ress->dstBuffer, 1, headerSize, ress->dstFile);
           if (sizeCheck!=headerSize) EXM_THROW(39, "Write error : cannot write end of stream"); }
@@ -623,7 +729,8 @@ static int FIO_compressFilename_internal(cRess_t ress,
             compressedfilesize = FIO_compressGzFrame(&ress, srcFileName, fileSize, compressionLevel, &readsize);
 #else
             (void)compressionLevel;
-            EXM_THROW(20, "zstd: %s: file cannot be compressed as gzip (zstd compiled without ZSTD_GZCOMPRESS) -- ignored \n", srcFileName);
+            EXM_THROW(20, "zstd: %s: file cannot be compressed as gzip (zstd compiled without ZSTD_GZCOMPRESS) -- ignored \n",
+                            srcFileName);
 #endif
             goto finish;
 
@@ -633,7 +740,8 @@ static int FIO_compressFilename_internal(cRess_t ress,
             compressedfilesize = FIO_compressLzmaFrame(&ress, srcFileName, fileSize, compressionLevel, &readsize, g_compressionType==FIO_lzmaCompression);
 #else
             (void)compressionLevel;
-            EXM_THROW(20, "zstd: %s: file cannot be compressed as xz/lzma (zstd compiled without ZSTD_LZMACOMPRESS) -- ignored \n", srcFileName);
+            EXM_THROW(20, "zstd: %s: file cannot be compressed as xz/lzma (zstd compiled without ZSTD_LZMACOMPRESS) -- ignored \n",
+                            srcFileName);
 #endif
             goto finish;
 
@@ -642,49 +750,62 @@ static int FIO_compressFilename_internal(cRess_t ress,
             compressedfilesize = FIO_compressLz4Frame(&ress, srcFileName, fileSize, compressionLevel, &readsize);
 #else
             (void)compressionLevel;
-            EXM_THROW(20, "zstd: %s: file cannot be compressed as lz4 (zstd compiled without ZSTD_LZ4COMPRESS) -- ignored \n", srcFileName);
+            EXM_THROW(20, "zstd: %s: file cannot be compressed as lz4 (zstd compiled without ZSTD_LZ4COMPRESS) -- ignored \n",
+                            srcFileName);
 #endif
             goto finish;
     }
 
     /* init */
-#ifdef ZSTD_MULTITHREAD
-    {   size_t const resetError = ZSTDMT_resetCStream(ress.cctx, fileSize);
+#ifdef ZSTD_NEWAPI
+    /* nothing, reset is implied */
+#elif defined(ZSTD_MULTITHREAD)
+    CHECK( ZSTDMT_resetCStream(ress.cctx, fileSize) );
 #else
-    {   size_t const resetError = ZSTD_resetCStream(ress.cctx, fileSize);
+    CHECK( ZSTD_resetCStream(ress.cctx, fileSize) );
 #endif
-        if (ZSTD_isError(resetError)) EXM_THROW(21, "Error initializing compression : %s", ZSTD_getErrorName(resetError));
-    }
 
     /* Main compression loop */
     while (1) {
         /* Fill input Buffer */
         size_t const inSize = fread(ress.srcBuffer, (size_t)1, ress.srcBufferSize, srcFile);
+        ZSTD_inBuffer inBuff = { ress.srcBuffer, inSize, 0 };
         if (inSize==0) break;
         readsize += inSize;
 
-        {   ZSTD_inBuffer  inBuff = { ress.srcBuffer, inSize, 0 };
-            while (inBuff.pos != inBuff.size) {
-                ZSTD_outBuffer outBuff = { ress.dstBuffer, ress.dstBufferSize, 0 };
-#ifdef ZSTD_MULTITHREAD
-                size_t const result = ZSTDMT_compressStream(ress.cctx, &outBuff, &inBuff);
+        while (inBuff.pos != inBuff.size) {
+            ZSTD_outBuffer outBuff = { ress.dstBuffer, ress.dstBufferSize, 0 };
+#ifdef ZSTD_NEWAPI
+            CHECK( ZSTD_compress_generic(ress.cctx,
+                        &outBuff, &inBuff, ZSTD_e_continue) );
+#elif defined(ZSTD_MULTITHREAD)
+            CHECK( ZSTDMT_compressStream(ress.cctx, &outBuff, &inBuff) );
 #else
-                size_t const result = ZSTD_compressStream(ress.cctx, &outBuff, &inBuff);
+            CHECK( ZSTD_compressStream(ress.cctx, &outBuff, &inBuff) );
 #endif
-                if (ZSTD_isError(result)) EXM_THROW(23, "Compression error : %s ", ZSTD_getErrorName(result));
-
-                /* Write compressed stream */
-                if (outBuff.pos) {
-                    size_t const sizeCheck = fwrite(ress.dstBuffer, 1, outBuff.pos, dstFile);
-                    if (sizeCheck!=outBuff.pos) EXM_THROW(25, "Write error : cannot write compressed block into %s", dstFileName);
-                    compressedfilesize += outBuff.pos;
-        }   }   }
+
+            /* Write compressed stream */
+            if (outBuff.pos) {
+                size_t const sizeCheck = fwrite(ress.dstBuffer, 1, outBuff.pos, dstFile);
+                if (sizeCheck!=outBuff.pos)
+                    EXM_THROW(25, "Write error : cannot write compressed block into %s", dstFileName);
+                compressedfilesize += outBuff.pos;
+        }   }
         if (g_nbThreads > 1) {
-            if (!fileSize) DISPLAYUPDATE(2, "\rRead : %u MB", (U32)(readsize>>20))
-            else DISPLAYUPDATE(2, "\rRead : %u / %u MB", (U32)(readsize>>20), (U32)(fileSize>>20));
+            if (!fileSize)
+                DISPLAYUPDATE(2, "\rRead : %u MB", (U32)(readsize>>20))
+            else
+                DISPLAYUPDATE(2, "\rRead : %u / %u MB",
+                                    (U32)(readsize>>20), (U32)(fileSize>>20));
         } else {
-            if (!fileSize) DISPLAYUPDATE(2, "\rRead : %u MB ==> %.2f%%", (U32)(readsize>>20), (double)compressedfilesize/readsize*100)
-            else DISPLAYUPDATE(2, "\rRead : %u / %u MB ==> %.2f%%", (U32)(readsize>>20), (U32)(fileSize>>20), (double)compressedfilesize/readsize*100);
+            if (!fileSize)
+                DISPLAYUPDATE(2, "\rRead : %u MB ==> %.2f%%",
+                                (U32)(readsize>>20),
+                                (double)compressedfilesize/readsize*100)
+            else
+            DISPLAYUPDATE(2, "\rRead : %u / %u MB ==> %.2f%%",
+                                (U32)(readsize>>20), (U32)(fileSize>>20),
+                                (double)compressedfilesize/readsize*100);
         }
     }
 
@@ -692,12 +813,18 @@ static int FIO_compressFilename_internal(cRess_t ress,
     {   size_t result = 1;
         while (result!=0) {   /* note : is there any possibility of endless loop ? */
             ZSTD_outBuffer outBuff = { ress.dstBuffer, ress.dstBufferSize, 0 };
-#ifdef ZSTD_MULTITHREAD
+#ifdef ZSTD_NEWAPI
+            ZSTD_inBuffer inBuff = { NULL, 0, 0};
+            result = ZSTD_compress_generic(ress.cctx,
+                        &outBuff, &inBuff, ZSTD_e_end);
+#elif defined(ZSTD_MULTITHREAD)
             result = ZSTDMT_endStream(ress.cctx, &outBuff);
 #else
             result = ZSTD_endStream(ress.cctx, &outBuff);
 #endif
-            if (ZSTD_isError(result)) EXM_THROW(26, "Compression error during frame end : %s", ZSTD_getErrorName(result));
+            if (ZSTD_isError(result))
+                EXM_THROW(26, "Compression error during frame end : %s",
+                            ZSTD_getErrorName(result));
             { size_t const sizeCheck = fwrite(ress.dstBuffer, 1, outBuff.pos, dstFile);
               if (sizeCheck!=outBuff.pos) EXM_THROW(27, "Write error : cannot write frame end into %s", dstFileName); }
             compressedfilesize += outBuff.pos;
@@ -722,7 +849,8 @@ finish:
  *            1 : missing or pb opening srcFileName
  */
 static int FIO_compressFilename_srcFile(cRess_t ress,
-                                        const char* dstFileName, const char* srcFileName, int compressionLevel)
+                            const char* dstFileName, const char* srcFileName,
+                            int compressionLevel)
 {
     int result;
 
@@ -751,7 +879,9 @@ static int FIO_compressFilename_srcFile(cRess_t ress,
  *            1 : pb
  */
 static int FIO_compressFilename_dstFile(cRess_t ress,
-                                        const char* dstFileName, const char* srcFileName, int compressionLevel)
+                                        const char* dstFileName,
+                                        const char* srcFileName,
+                                        int compressionLevel)
 {
     int result;
     stat_t statbuf;
@@ -760,12 +890,20 @@ static int FIO_compressFilename_dstFile(cRess_t ress,
     ress.dstFile = FIO_openDstFile(dstFileName);
     if (ress.dstFile==NULL) return 1;  /* could not open dstFileName */
 
-    if (strcmp (srcFileName, stdinmark) && UTIL_getFileStat(srcFileName, &statbuf)) stat_result = 1;
+    if (strcmp (srcFileName, stdinmark) && UTIL_getFileStat(srcFileName, &statbuf))
+        stat_result = 1;
     result = FIO_compressFilename_srcFile(ress, dstFileName, srcFileName, compressionLevel);
 
-    if (fclose(ress.dstFile)) { DISPLAYLEVEL(1, "zstd: %s: %s \n", dstFileName, strerror(errno)); result=1; }  /* error closing dstFile */
-    if (result!=0) { if (remove(dstFileName)) EXM_THROW(1, "zstd: %s: %s", dstFileName, strerror(errno)); }  /* remove operation artefact */
-    else if (strcmp (dstFileName, stdoutmark) && stat_result) UTIL_setFileStat(dstFileName, &statbuf);
+    if (fclose(ress.dstFile)) { /* error closing dstFile */
+        DISPLAYLEVEL(1, "zstd: %s: %s \n", dstFileName, strerror(errno));
+        result=1;
+    }
+    if (result!=0) {  /* remove operation artefact */
+        if (remove(dstFileName))
+            EXM_THROW(1, "zstd: %s: %s", dstFileName, strerror(errno));
+    }
+    else if (strcmp (dstFileName, stdoutmark) && stat_result)
+        UTIL_setFileStat(dstFileName, &statbuf);
     return result;
 }
 
@@ -775,9 +913,9 @@ int FIO_compressFilename(const char* dstFileName, const char* srcFileName,
 {
     clock_t const start = clock();
     U64 const srcSize = UTIL_getFileSize(srcFileName);
-    int const regFile = UTIL_isRegFile(srcFileName);
+    int const isRegularFile = UTIL_isRegularFile(srcFileName);
 
-    cRess_t const ress = FIO_createCResources(dictFileName, compressionLevel, srcSize, regFile, comprParams);
+    cRess_t const ress = FIO_createCResources(dictFileName, compressionLevel, srcSize, isRegularFile, comprParams);
     int const result = FIO_compressFilename_dstFile(ress, dstFileName, srcFileName, compressionLevel);
 
     double const seconds = (double)(clock() - start) / CLOCKS_PER_SEC;
@@ -787,6 +925,230 @@ int FIO_compressFilename(const char* dstFileName, const char* srcFileName,
     return result;
 }
 
+typedef struct {
+    int numActualFrames;
+    int numSkippableFrames;
+    unsigned long long decompressedSize;
+    int decompUnavailable;
+    unsigned long long compressedSize;
+    int usesCheck;
+} fileInfo_t;
+
+/*
+ * Reads information from file, stores in *info
+ * if successful, returns 0, returns 1 for frame analysis error, returns 2 for file not compressed with zstd
+ * returns 3 for cases in which file could not be opened.
+ */
+static int getFileInfo(fileInfo_t* info, const char* inFileName){
+    int detectError = 0;
+    FILE* const srcFile = FIO_openSrcFile(inFileName);
+    if (srcFile == NULL) {
+        DISPLAY("Error: could not open source file %s\n", inFileName);
+        return 3;
+    }
+    info->compressedSize = (unsigned long long)UTIL_getFileSize(inFileName);
+    /* begin analyzing frame */
+    for ( ; ; ) {
+        BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX];
+        size_t const numBytesRead = fread(headerBuffer, 1, sizeof(headerBuffer), srcFile);
+        if (numBytesRead < ZSTD_frameHeaderSize_min) {
+            if (feof(srcFile) && numBytesRead == 0 && info->compressedSize > 0) {
+                break;
+            }
+            else if (feof(srcFile)) {
+                DISPLAY("Error: reached end of file with incomplete frame\n");
+                detectError = 2;
+                break;
+            }
+            else {
+                DISPLAY("Error: did not reach end of file but ran out of frames\n");
+                detectError = 1;
+                break;
+            }
+        }
+        {
+            U32 const magicNumber = MEM_readLE32(headerBuffer);
+            if (magicNumber == ZSTD_MAGICNUMBER) {
+                U64 const frameContentSize = ZSTD_getFrameContentSize(headerBuffer, numBytesRead);
+                if (frameContentSize == ZSTD_CONTENTSIZE_ERROR || frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN) {
+                    info->decompUnavailable = 1;
+                }
+                else {
+                    info->decompressedSize += frameContentSize;
+                }
+                {
+                    /* move to the end of the frame header */
+                    size_t const headerSize = ZSTD_frameHeaderSize(headerBuffer, numBytesRead);
+                    if (ZSTD_isError(headerSize)) {
+                        DISPLAY("Error: could not determine frame header size\n");
+                        detectError = 1;
+                        break;
+                    }
+                    {
+                        int const ret = fseek(srcFile, ((long)headerSize)-((long)numBytesRead), SEEK_CUR);
+                        if (ret != 0) {
+                            DISPLAY("Error: could not move to end of frame header\n");
+                            detectError = 1;
+                            break;
+                        }
+                    }
+                }
+
+                /* skip the rest of the blocks in the frame */
+                {
+                    int lastBlock = 0;
+                    do {
+                        BYTE blockHeaderBuffer[3];
+                        U32 blockHeader;
+                        int blockSize;
+                        size_t const readBytes = fread(blockHeaderBuffer, 1, 3, srcFile);
+                        if (readBytes != 3) {
+                            DISPLAY("There was a problem reading the block header\n");
+                            detectError = 1;
+                            break;
+                        }
+                        blockHeader = MEM_readLE24(blockHeaderBuffer);
+                        lastBlock = blockHeader & 1;
+                        blockSize = blockHeader >> 3;
+                        {
+                            int const ret = fseek(srcFile, blockSize, SEEK_CUR);
+                            if (ret != 0) {
+                                DISPLAY("Error: could not skip to end of block\n");
+                                detectError = 1;
+                                break;
+                            }
+                        }
+                    } while (lastBlock != 1);
+
+                    if (detectError) {
+                        break;
+                    }
+                }
+                {
+                    /* check if checksum is used */
+                    BYTE const frameHeaderDescriptor = headerBuffer[4];
+                    int const contentChecksumFlag = (frameHeaderDescriptor & (1 << 2)) >> 2;
+                    if (contentChecksumFlag) {
+                        int const ret = fseek(srcFile, 4, SEEK_CUR);
+                        info->usesCheck = 1;
+                        if (ret != 0) {
+                            DISPLAY("Error: could not skip past checksum\n");
+                            detectError = 1;
+                            break;
+                        }
+                    }
+                }
+                info->numActualFrames++;
+            }
+            else if (magicNumber == ZSTD_MAGIC_SKIPPABLE_START) {
+                BYTE frameSizeBuffer[4];
+                size_t const readBytes = fread(frameSizeBuffer, 1, 4, srcFile);
+                if (readBytes != 4) {
+                    DISPLAY("There was an error reading skippable frame size");
+                    detectError = 1;
+                    break;
+                }
+                {
+                    U32 const frameSize = MEM_readLE32(frameSizeBuffer);
+                    int const ret = LONG_SEEK(srcFile, frameSize, SEEK_CUR);
+                    if (ret != 0) {
+                        DISPLAY("Error: could not find end of skippable frame\n");
+                        detectError = 1;
+                        break;
+                    }
+                }
+                info->numSkippableFrames++;
+            }
+            else {
+                detectError = 2;
+                break;
+            }
+        }
+    }
+    fclose(srcFile);
+    return detectError;
+}
+
+static void displayInfo(const char* inFileName, fileInfo_t* info, int displayLevel){
+    double const compressedSizeMB = (double)info->compressedSize/(1 MB);
+    double const decompressedSizeMB = (double)info->decompressedSize/(1 MB);
+    double const ratio = (info->compressedSize == 0) ? 0 : ((double)info->decompressedSize)/info->compressedSize;
+    const char* const checkString = (info->usesCheck ? "XXH64" : "None");
+    if (displayLevel <= 2) {
+        if (!info->decompUnavailable) {
+            DISPLAYOUT("Skippable  Non-Skippable  Compressed  Uncompressed  Ratio  Check  Filename\n");
+            DISPLAYOUT("%9d  %13d  %7.2f MB  %9.2f MB  %5.3f  %5s  %s\n",
+                    info->numSkippableFrames, info->numActualFrames, compressedSizeMB, decompressedSizeMB,
+                    ratio, checkString, inFileName);
+        }
+        else {
+            DISPLAYOUT("Skippable  Non-Skippable  Compressed  Check  Filename\n");
+            DISPLAYOUT("%9d  %13d  %7.2f MB  %5s  %s\n",
+                    info->numSkippableFrames, info->numActualFrames, compressedSizeMB, checkString, inFileName);
+        }
+    }
+    else{
+        DISPLAYOUT("# Zstandard Frames: %d\n", info->numActualFrames);
+        DISPLAYOUT("# Skippable Frames: %d\n", info->numSkippableFrames);
+        DISPLAYOUT("Compressed Size: %.2f MB (%llu B)\n", compressedSizeMB, info->compressedSize);
+        if (!info->decompUnavailable) {
+            DISPLAYOUT("Decompressed Size: %.2f MB (%llu B)\n", decompressedSizeMB, info->decompressedSize);
+            DISPLAYOUT("Ratio: %.4f\n", ratio);
+        }
+        DISPLAYOUT("Check: %s\n", checkString);
+        DISPLAYOUT("\n");
+    }
+}
+
+
+static int FIO_listFile(const char* inFileName, int displayLevel, unsigned fileNo, unsigned numFiles){
+    /* initialize info to avoid warnings */
+    fileInfo_t info;
+    memset(&info, 0, sizeof(info));
+    DISPLAYOUT("%s (%u/%u):\n", inFileName, fileNo, numFiles);
+    {
+        int const error = getFileInfo(&info, inFileName);
+        if (error == 1) {
+            /* display error, but provide output */
+            DISPLAY("An error occurred with getting file info\n");
+        }
+        else if (error == 2) {
+            DISPLAYOUT("File %s not compressed with zstd\n", inFileName);
+            if (displayLevel > 2) {
+                DISPLAYOUT("\n");
+            }
+            return 1;
+        }
+        else if (error == 3) {
+            /* error occurred with opening the file */
+            if (displayLevel > 2) {
+                DISPLAYOUT("\n");
+            }
+            return 1;
+        }
+        displayInfo(inFileName, &info, displayLevel);
+        return error;
+    }
+}
+
+int FIO_listMultipleFiles(unsigned numFiles, const char** filenameTable, int displayLevel){
+    if (numFiles == 0) {
+        DISPLAYOUT("No files given\n");
+        return 0;
+    }
+    DISPLAYOUT("===========================================\n");
+    DISPLAYOUT("Printing information about compressed files\n");
+    DISPLAYOUT("===========================================\n");
+    DISPLAYOUT("Number of files listed: %u\n", numFiles);
+    {
+        int error = 0;
+        unsigned u;
+        for (u=0; u<numFiles;u++) {
+            error |= FIO_listFile(filenameTable[u], displayLevel, u+1, numFiles);
+        }
+        return error;
+    }
+}
 
 int FIO_compressMultipleFilenames(const char** inFileNamesTable, unsigned nbFiles,
                                   const char* suffix,
@@ -798,12 +1160,14 @@ int FIO_compressMultipleFilenames(const char** inFileNamesTable, unsigned nbFile
     char*  dstFileName = (char*)malloc(FNSPACE);
     size_t const suffixSize = suffix ? strlen(suffix) : 0;
     U64 const srcSize = (nbFiles != 1) ? 0 : UTIL_getFileSize(inFileNamesTable[0]) ;
-    int const regFile = (nbFiles != 1) ? 0 : UTIL_isRegFile(inFileNamesTable[0]);
-    cRess_t ress = FIO_createCResources(dictFileName, compressionLevel, srcSize, regFile, comprParams);
+    int const isRegularFile = (nbFiles != 1) ? 0 : UTIL_isRegularFile(inFileNamesTable[0]);
+    cRess_t ress = FIO_createCResources(dictFileName, compressionLevel, srcSize, isRegularFile, comprParams);
 
     /* init */
-    if (dstFileName==NULL) EXM_THROW(27, "FIO_compressMultipleFilenames : allocation error for dstFileName");
-    if (suffix == NULL) EXM_THROW(28, "FIO_compressMultipleFilenames : dst unknown");  /* should never happen */
+    if (dstFileName==NULL)
+        EXM_THROW(27, "FIO_compressMultipleFilenames : allocation error for dstFileName");
+    if (suffix == NULL)
+        EXM_THROW(28, "FIO_compressMultipleFilenames : dst unknown");  /* should never happen */
 
     /* loop on each file */
     if (!strcmp(suffix, stdoutmark)) {
@@ -812,12 +1176,19 @@ int FIO_compressMultipleFilenames(const char** inFileNamesTable, unsigned nbFile
         SET_BINARY_MODE(stdout);
         for (u=0; u<nbFiles; u++)
             missed_files += FIO_compressFilename_srcFile(ress, stdoutmark, inFileNamesTable[u], compressionLevel);
-        if (fclose(ress.dstFile)) EXM_THROW(29, "Write error : cannot properly close stdout");
+        if (fclose(ress.dstFile))
+            EXM_THROW(29, "Write error : cannot properly close stdout");
     } else {
         unsigned u;
         for (u=0; u<nbFiles; u++) {
-            size_t ifnSize = strlen(inFileNamesTable[u]);
-            if (dfnSize <= ifnSize+suffixSize+1) { free(dstFileName); dfnSize = ifnSize + 20; dstFileName = (char*)malloc(dfnSize); }
+            size_t const ifnSize = strlen(inFileNamesTable[u]);
+            if (dfnSize <= ifnSize+suffixSize+1) {  /* resize name buffer */
+                free(dstFileName);
+                dfnSize = ifnSize + 20;
+                dstFileName = (char*)malloc(dfnSize);
+                if (!dstFileName)
+                    EXM_THROW(30, "zstd: %s", strerror(errno));
+            }
             strcpy(dstFileName, inFileNamesTable[u]);
             strcat(dstFileName, suffix);
             missed_files += FIO_compressFilename_dstFile(ress, dstFileName, inFileNamesTable[u], compressionLevel);
@@ -862,13 +1233,13 @@ static dRess_t FIO_createDResources(const char* dictFileName)
     ress.srcBuffer = malloc(ress.srcBufferSize);
     ress.dstBufferSize = ZSTD_DStreamOutSize();
     ress.dstBuffer = malloc(ress.dstBufferSize);
-    if (!ress.srcBuffer || !ress.dstBuffer) EXM_THROW(61, "Allocation error : not enough memory");
+    if (!ress.srcBuffer || !ress.dstBuffer)
+        EXM_THROW(61, "Allocation error : not enough memory");
 
     /* dictionary */
     {   void* dictBuffer;
         size_t const dictBufferSize = FIO_createDictBuffer(&dictBuffer, dictFileName);
-        size_t const initError = ZSTD_initDStream_usingDict(ress.dctx, dictBuffer, dictBufferSize);
-        if (ZSTD_isError(initError)) EXM_THROW(61, "ZSTD_initDStream_usingDict error : %s", ZSTD_getErrorName(initError));
+        CHECK( ZSTD_initDStream_usingDict(ress.dctx, dictBuffer, dictBufferSize) );
         free(dictBuffer);
     }
 
@@ -877,8 +1248,7 @@ static dRess_t FIO_createDResources(const char* dictFileName)
 
 static void FIO_freeDResources(dRess_t ress)
 {
-    size_t const errorCode = ZSTD_freeDStream(ress.dctx);
-    if (ZSTD_isError(errorCode)) EXM_THROW(69, "Error : can't free ZSTD_DStream context resource : %s", ZSTD_getErrorName(errorCode));
+    CHECK( ZSTD_freeDStream(ress.dctx) );
     free(ress.srcBuffer);
     free(ress.dstBuffer);
 }
@@ -924,13 +1294,15 @@ static unsigned FIO_fwriteSparse(FILE* file, const void* buffer, size_t bufferSi
             seg0SizeT -= nb0T;
             ptrT += nb0T;
             {   size_t const sizeCheck = fwrite(ptrT, sizeof(size_t), seg0SizeT, file);
-                if (sizeCheck != seg0SizeT) EXM_THROW(73, "Write error : cannot write decoded block");
+                if (sizeCheck != seg0SizeT)
+                    EXM_THROW(73, "Write error : cannot write decoded block");
         }   }
         ptrT += seg0SizeT;
     }
 
     {   static size_t const maskT = sizeof(size_t)-1;
-        if (bufferSize & maskT) {   /* size not multiple of sizeof(size_t) : implies end of block */
+        if (bufferSize & maskT) {
+            /* size not multiple of sizeof(size_t) : implies end of block */
             const char* const restStart = (const char*)bufferTEnd;
             const char* restPtr = restStart;
             size_t restSize =  bufferSize & maskT;
@@ -939,10 +1311,12 @@ static unsigned FIO_fwriteSparse(FILE* file, const void* buffer, size_t bufferSi
             storedSkips += (unsigned) (restPtr - restStart);
             if (restPtr != restEnd) {
                 int seekResult = LONG_SEEK(file, storedSkips, SEEK_CUR);
-                if (seekResult) EXM_THROW(74, "Sparse skip error ; try --no-sparse");
+                if (seekResult)
+                    EXM_THROW(74, "Sparse skip error ; try --no-sparse");
                 storedSkips = 0;
                 {   size_t const sizeCheck = fwrite(restPtr, 1, restEnd - restPtr, file);
-                    if (sizeCheck != (size_t)(restEnd - restPtr)) EXM_THROW(75, "Write error : cannot write decoded end of block");
+                    if (sizeCheck != (size_t)(restEnd - restPtr))
+                        EXM_THROW(75, "Write error : cannot write decoded end of block");
     }   }   }   }
 
     return storedSkips;
@@ -955,7 +1329,8 @@ static void FIO_fwriteSparseEnd(FILE* file, unsigned storedSkips)
         if (seekResult != 0) EXM_THROW(69, "Final skip error (sparse file)");
         {   const char lastZeroByte[1] = { 0 };
             size_t const sizeCheck = fwrite(lastZeroByte, 1, 1, file);
-            if (sizeCheck != 1) EXM_THROW(69, "Write error : cannot write last zero");
+            if (sizeCheck != 1)
+                EXM_THROW(69, "Write error : cannot write last zero");
     }   }
 }
 
@@ -969,8 +1344,11 @@ static unsigned FIO_passThrough(FILE* foutput, FILE* finput, void* buffer, size_
     unsigned storedSkips = 0;
 
     /* assumption : ress->srcBufferLoaded bytes already loaded and stored within buffer */
-    { size_t const sizeCheck = fwrite(buffer, 1, alreadyLoaded, foutput);
-      if (sizeCheck != alreadyLoaded) EXM_THROW(50, "Pass-through write error"); }
+    {   size_t const sizeCheck = fwrite(buffer, 1, alreadyLoaded, foutput);
+        if (sizeCheck != alreadyLoaded) {
+            DISPLAYLEVEL(1, "Pass-through write error \n");
+            return 1;
+    }   }
 
     while (readFromInput) {
         readFromInput = fread(buffer, 1, blockSize, finput);
@@ -983,16 +1361,19 @@ static unsigned FIO_passThrough(FILE* foutput, FILE* finput, void* buffer, size_
 
 
 /** FIO_decompressFrame() :
-    @return : size of decoded frame
+ *  @return : size of decoded zstd frame, or an error code
 */
-unsigned long long FIO_decompressFrame(dRess_t* ress,
+#define FIO_ERROR_FRAME_DECODING   ((unsigned long long)(-2))
+unsigned long long FIO_decompressZstdFrame(dRess_t* ress,
                                        FILE* finput,
+                                       const char* srcFileName,
                                        U64 alreadyDecoded)
 {
     U64 frameSize = 0;
     U32 storedSkips = 0;
 
     ZSTD_resetDStream(ress->dctx);
+    if (strlen(srcFileName)>20) srcFileName += strlen(srcFileName)-20;   /* display last 20 characters */
 
     /* Header loading (optional, saves one loop) */
     {   size_t const toRead = 9;
@@ -1005,12 +1386,17 @@ unsigned long long FIO_decompressFrame(dRess_t* ress,
         ZSTD_inBuffer  inBuff = { ress->srcBuffer, ress->srcBufferLoaded, 0 };
         ZSTD_outBuffer outBuff= { ress->dstBuffer, ress->dstBufferSize, 0 };
         size_t const readSizeHint = ZSTD_decompressStream(ress->dctx, &outBuff, &inBuff);
-        if (ZSTD_isError(readSizeHint)) EXM_THROW(36, "Decoding error : %s", ZSTD_getErrorName(readSizeHint));
+        if (ZSTD_isError(readSizeHint)) {
+            DISPLAYLEVEL(1, "%s : Decoding error (36) : %s \n",
+                            srcFileName, ZSTD_getErrorName(readSizeHint));
+            return FIO_ERROR_FRAME_DECODING;
+        }
 
         /* Write block */
         storedSkips = FIO_fwriteSparse(ress->dstFile, ress->dstBuffer, outBuff.pos, storedSkips);
         frameSize += outBuff.pos;
-        DISPLAYUPDATE(2, "\rDecoded : %u MB...     ", (U32)((alreadyDecoded+frameSize)>>20) );
+        DISPLAYUPDATE(2, "\r%-20.20s : %u MB...     ",
+                         srcFileName, (U32)((alreadyDecoded+frameSize)>>20) );
 
         if (inBuff.pos > 0) {
             memmove(ress->srcBuffer, (char*)ress->srcBuffer + inBuff.pos, inBuff.size - inBuff.pos);
@@ -1018,14 +1404,22 @@ unsigned long long FIO_decompressFrame(dRess_t* ress,
         }
 
         if (readSizeHint == 0) break;   /* end of frame */
-        if (inBuff.size != inBuff.pos) EXM_THROW(37, "Decoding error : should consume entire input");
+        if (inBuff.size != inBuff.pos) {
+            DISPLAYLEVEL(1, "%s : Decoding error (37) : should consume entire input \n",
+                            srcFileName);
+            return FIO_ERROR_FRAME_DECODING;
+        }
 
         /* Fill input buffer */
         {   size_t const toRead = MIN(readSizeHint, ress->srcBufferSize);  /* support large skippable frames */
             if (ress->srcBufferLoaded < toRead)
-                ress->srcBufferLoaded += fread(((char*)ress->srcBuffer) + ress->srcBufferLoaded, 1, toRead - ress->srcBufferLoaded, finput);
-            if (ress->srcBufferLoaded < toRead) EXM_THROW(39, "Read error : premature end");
-    }   }
+                ress->srcBufferLoaded += fread((char*)ress->srcBuffer + ress->srcBufferLoaded,
+                                               1, toRead - ress->srcBufferLoaded, finput);
+            if (ress->srcBufferLoaded < toRead) {
+                DISPLAYLEVEL(1, "%s : Read error (39) : premature end \n",
+                                srcFileName);
+                return FIO_ERROR_FRAME_DECODING;
+    }   }   }
 
     FIO_fwriteSparseEnd(ress->dstFile, storedSkips);
 
@@ -1034,19 +1428,22 @@ unsigned long long FIO_decompressFrame(dRess_t* ress,
 
 
 #ifdef ZSTD_GZDECOMPRESS
-static unsigned long long FIO_decompressGzFrame(dRess_t* ress, FILE* srcFile, const char* srcFileName)
+static unsigned long long FIO_decompressGzFrame(dRess_t* ress,
+                                    FILE* srcFile, const char* srcFileName)
 {
     unsigned long long outFileSize = 0;
     z_stream strm;
     int flush = Z_NO_FLUSH;
-    int ret;
+    int decodingError = 0;
 
     strm.zalloc = Z_NULL;
     strm.zfree = Z_NULL;
     strm.opaque = Z_NULL;
     strm.next_in = 0;
     strm.avail_in = 0;
-    if (inflateInit2(&strm, 15 /* maxWindowLogSize */ + 16 /* gzip only */) != Z_OK) return 0;  /* see http://www.zlib.net/manual.html */
+    /* see http://www.zlib.net/manual.html */
+    if (inflateInit2(&strm, 15 /* maxWindowLogSize */ + 16 /* gzip only */) != Z_OK)
+        return FIO_ERROR_FRAME_DECODING;
 
     strm.next_out = (Bytef*)ress->dstBuffer;
     strm.avail_out = (uInt)ress->dstBufferSize;
@@ -1054,6 +1451,7 @@ static unsigned long long FIO_decompressGzFrame(dRess_t* ress, FILE* srcFile, co
     strm.next_in = (z_const unsigned char*)ress->srcBuffer;
 
     for ( ; ; ) {
+        int ret;
         if (strm.avail_in == 0) {
             ress->srcBufferLoaded = fread(ress->srcBuffer, 1, ress->srcBufferSize, srcFile);
             if (ress->srcBufferLoaded == 0) flush = Z_FINISH;
@@ -1061,11 +1459,20 @@ static unsigned long long FIO_decompressGzFrame(dRess_t* ress, FILE* srcFile, co
             strm.avail_in = (uInt)ress->srcBufferLoaded;
         }
         ret = inflate(&strm, flush);
-        if (ret == Z_BUF_ERROR) EXM_THROW(39, "zstd: %s: premature end", srcFileName);
-        if (ret != Z_OK && ret != Z_STREAM_END) { DISPLAY("zstd: %s: inflate error %d \n", srcFileName, ret); return 0; }
+        if (ret == Z_BUF_ERROR) {
+            DISPLAYLEVEL(1, "zstd: %s: premature gz end \n", srcFileName);
+            decodingError = 1; break;
+        }
+        if (ret != Z_OK && ret != Z_STREAM_END) {
+            DISPLAYLEVEL(1, "zstd: %s: inflate error %d \n", srcFileName, ret);
+            decodingError = 1; break;
+        }
         {   size_t const decompBytes = ress->dstBufferSize - strm.avail_out;
             if (decompBytes) {
-                if (fwrite(ress->dstBuffer, 1, decompBytes, ress->dstFile) != decompBytes) EXM_THROW(31, "Write error : cannot write to output file");
+                if (fwrite(ress->dstBuffer, 1, decompBytes, ress->dstFile) != decompBytes) {
+                    DISPLAYLEVEL(1, "zstd: %s \n", strerror(errno));
+                    decodingError = 1; break;
+                }
                 outFileSize += decompBytes;
                 strm.next_out = (Bytef*)ress->dstBuffer;
                 strm.avail_out = (uInt)ress->dstBufferSize;
@@ -1074,11 +1481,15 @@ static unsigned long long FIO_decompressGzFrame(dRess_t* ress, FILE* srcFile, co
         if (ret == Z_STREAM_END) break;
     }
 
-    if (strm.avail_in > 0) memmove(ress->srcBuffer, strm.next_in, strm.avail_in);
+    if (strm.avail_in > 0)
+        memmove(ress->srcBuffer, strm.next_in, strm.avail_in);
     ress->srcBufferLoaded = strm.avail_in;
-    ret = inflateEnd(&strm);
-    if (ret != Z_OK) EXM_THROW(32, "zstd: %s: inflateEnd error %d", srcFileName, ret);
-    return outFileSize;
+    if ( (inflateEnd(&strm) != Z_OK)  /* release resources ; error detected */
+      && (decodingError==0) ) {
+        DISPLAYLEVEL(1, "zstd: %s: inflateEnd error \n", srcFileName);
+        decodingError = 1;
+    }
+    return decodingError ? FIO_ERROR_FRAME_DECODING : outFileSize;
 }
 #endif
 
@@ -1089,69 +1500,95 @@ static unsigned long long FIO_decompressLzmaFrame(dRess_t* ress, FILE* srcFile,
     unsigned long long outFileSize = 0;
     lzma_stream strm = LZMA_STREAM_INIT;
     lzma_action action = LZMA_RUN;
-    lzma_ret ret;
+    lzma_ret initRet;
+    int decodingError = 0;
 
     strm.next_in = 0;
     strm.avail_in = 0;
     if (plain_lzma) {
-        ret = lzma_alone_decoder(&strm, UINT64_MAX); /* LZMA */
+        initRet = lzma_alone_decoder(&strm, UINT64_MAX); /* LZMA */
     } else {
-        ret = lzma_stream_decoder(&strm, UINT64_MAX, 0); /* XZ */
+        initRet = lzma_stream_decoder(&strm, UINT64_MAX, 0); /* XZ */
     }
 
-    if (ret != LZMA_OK) EXM_THROW(71, "zstd: %s: lzma_alone_decoder/lzma_stream_decoder error %d", srcFileName, ret);
+    if (initRet != LZMA_OK) {
+        DISPLAYLEVEL(1, "zstd: %s: %s error %d \n",
+                        plain_lzma ? "lzma_alone_decoder" : "lzma_stream_decoder",
+                        srcFileName, initRet);
+        return FIO_ERROR_FRAME_DECODING;
+    }
 
-    strm.next_out = ress->dstBuffer;
+    strm.next_out = (BYTE*)ress->dstBuffer;
     strm.avail_out = ress->dstBufferSize;
+    strm.next_in = (BYTE const*)ress->srcBuffer;
     strm.avail_in = ress->srcBufferLoaded;
-    strm.next_in = ress->srcBuffer;
 
     for ( ; ; ) {
+        lzma_ret ret;
         if (strm.avail_in == 0) {
             ress->srcBufferLoaded = fread(ress->srcBuffer, 1, ress->srcBufferSize, srcFile);
             if (ress->srcBufferLoaded == 0) action = LZMA_FINISH;
-            strm.next_in = ress->srcBuffer;
+            strm.next_in = (BYTE const*)ress->srcBuffer;
             strm.avail_in = ress->srcBufferLoaded;
         }
         ret = lzma_code(&strm, action);
 
-        if (ret == LZMA_BUF_ERROR) EXM_THROW(39, "zstd: %s: premature end", srcFileName);
-        if (ret != LZMA_OK && ret != LZMA_STREAM_END) { DISPLAY("zstd: %s: lzma_code decoding error %d \n", srcFileName, ret); return 0; }
+        if (ret == LZMA_BUF_ERROR) {
+            DISPLAYLEVEL(1, "zstd: %s: premature lzma end \n", srcFileName);
+            decodingError = 1; break;
+        }
+        if (ret != LZMA_OK && ret != LZMA_STREAM_END) {
+            DISPLAYLEVEL(1, "zstd: %s: lzma_code decoding error %d \n",
+                            srcFileName, ret);
+            decodingError = 1; break;
+        }
         {   size_t const decompBytes = ress->dstBufferSize - strm.avail_out;
             if (decompBytes) {
-                if (fwrite(ress->dstBuffer, 1, decompBytes, ress->dstFile) != decompBytes) EXM_THROW(31, "Write error : cannot write to output file");
+                if (fwrite(ress->dstBuffer, 1, decompBytes, ress->dstFile) != decompBytes) {
+                    DISPLAYLEVEL(1, "zstd: %s \n", strerror(errno));
+                    decodingError = 1; break;
+                }
                 outFileSize += decompBytes;
-                strm.next_out = ress->dstBuffer;
+                strm.next_out = (BYTE*)ress->dstBuffer;
                 strm.avail_out = ress->dstBufferSize;
-            }
-        }
+        }   }
         if (ret == LZMA_STREAM_END) break;
     }
 
-    if (strm.avail_in > 0) memmove(ress->srcBuffer, strm.next_in, strm.avail_in);
+    if (strm.avail_in > 0)
+        memmove(ress->srcBuffer, strm.next_in, strm.avail_in);
     ress->srcBufferLoaded = strm.avail_in;
     lzma_end(&strm);
-    return outFileSize;
+    return decodingError ? FIO_ERROR_FRAME_DECODING : outFileSize;
 }
 #endif
 
 #ifdef ZSTD_LZ4DECOMPRESS
-static unsigned long long FIO_decompressLz4Frame(dRess_t* ress, FILE* srcFile, const char* srcFileName)
+static unsigned long long FIO_decompressLz4Frame(dRess_t* ress,
+                                    FILE* srcFile, const char* srcFileName)
 {
     unsigned long long filesize = 0;
     LZ4F_errorCode_t nextToLoad;
     LZ4F_decompressionContext_t dCtx;
     LZ4F_errorCode_t const errorCode = LZ4F_createDecompressionContext(&dCtx, LZ4F_VERSION);
+    int decodingError = 0;
 
-    if (LZ4F_isError(errorCode)) EXM_THROW(61, "zstd: failed to create lz4 decompression context");
+    if (LZ4F_isError(errorCode)) {
+        DISPLAYLEVEL(1, "zstd: failed to create lz4 decompression context \n");
+        return FIO_ERROR_FRAME_DECODING;
+    }
 
     /* Init feed with magic number (already consumed from FILE* sFile) */
     {   size_t inSize = 4;
         size_t outSize= 0;
         MEM_writeLE32(ress->srcBuffer, LZ4_MAGICNUMBER);
         nextToLoad = LZ4F_decompress(dCtx, ress->dstBuffer, &outSize, ress->srcBuffer, &inSize, NULL);
-        if (LZ4F_isError(nextToLoad)) EXM_THROW(62, "zstd: %s: lz4 header error : %s", srcFileName, LZ4F_getErrorName(nextToLoad));
-    }
+        if (LZ4F_isError(nextToLoad)) {
+            DISPLAYLEVEL(1, "zstd: %s: lz4 header error : %s \n",
+                            srcFileName, LZ4F_getErrorName(nextToLoad));
+            LZ4F_freeDecompressionContext(dCtx);
+            return FIO_ERROR_FRAME_DECODING;
+    }   }
 
     /* Main Loop */
     for (;nextToLoad;) {
@@ -1169,12 +1606,19 @@ static unsigned long long FIO_decompressLz4Frame(dRess_t* ress, FILE* srcFile, c
             size_t remaining = readSize - pos;
             decodedBytes = ress->dstBufferSize;
             nextToLoad = LZ4F_decompress(dCtx, ress->dstBuffer, &decodedBytes, (char*)(ress->srcBuffer)+pos, &remaining, NULL);
-            if (LZ4F_isError(nextToLoad)) EXM_THROW(66, "zstd: %s: decompression error : %s", srcFileName, LZ4F_getErrorName(nextToLoad));
+            if (LZ4F_isError(nextToLoad)) {
+                DISPLAYLEVEL(1, "zstd: %s: lz4 decompression error : %s \n",
+                                srcFileName, LZ4F_getErrorName(nextToLoad));
+                decodingError = 1; break;
+            }
             pos += remaining;
 
             /* Write Block */
             if (decodedBytes) {
-                if (fwrite(ress->dstBuffer, 1, decodedBytes, ress->dstFile) != decodedBytes) EXM_THROW(63, "Write error : cannot write to output file");
+                if (fwrite(ress->dstBuffer, 1, decodedBytes, ress->dstFile) != decodedBytes) {
+                    DISPLAYLEVEL(1, "zstd: %s \n", strerr(errno));
+                    decodingError = 1; break;
+                }
                 filesize += decodedBytes;
                 DISPLAYUPDATE(2, "\rDecompressed : %u MB  ", (unsigned)(filesize>>20));
             }
@@ -1183,105 +1627,143 @@ static unsigned long long FIO_decompressLz4Frame(dRess_t* ress, FILE* srcFile, c
         }
     }
     /* can be out because readSize == 0, which could be an fread() error */
-    if (ferror(srcFile)) EXM_THROW(67, "zstd: %s: read error", srcFileName);
+    if (ferror(srcFile)) {
+        DISPLAYLEVEL(1, "zstd: %s: read error \n", srcFileName);
+        decodingError=1;
+    }
 
-    if (nextToLoad!=0) EXM_THROW(68, "zstd: %s: unfinished stream", srcFileName);
+    if (nextToLoad!=0) {
+        DISPLAYLEVEL(1, "zstd: %s: unfinished lz4 stream \n", srcFileName);
+        decodingError=1;
+    }
 
     LZ4F_freeDecompressionContext(dCtx);
-    ress->srcBufferLoaded = 0; /* LZ4F will go to the frame boundary */
+    ress->srcBufferLoaded = 0; /* LZ4F will reach exact frame boundary */
 
-    return filesize;
+    return decodingError ? FIO_ERROR_FRAME_DECODING : filesize;
 }
 #endif
 
 
 
-/** FIO_decompressSrcFile() :
-    Decompression `srcFileName` into `ress.dstFile`
-    @return : 0 : OK
-              1 : operation not started
-*/
-static int FIO_decompressSrcFile(dRess_t ress, const char* dstFileName, const char* srcFileName)
+/** FIO_decompressFrames() :
+ *  Find and decode frames inside srcFile
+ *  srcFile presumed opened and valid
+ * @return : 0 : OK
+ *           1 : error
+ */
+static int FIO_decompressFrames(dRess_t ress, FILE* srcFile,
+                        const char* dstFileName, const char* srcFileName)
 {
-    FILE* srcFile;
     unsigned readSomething = 0;
     unsigned long long filesize = 0;
-
-    if (UTIL_isDirectory(srcFileName)) {
-        DISPLAYLEVEL(1, "zstd: %s is a directory -- ignored \n", srcFileName);
-        return 1;
-    }
-
-    srcFile = FIO_openSrcFile(srcFileName);
-    if (srcFile==NULL) return 1;
+    assert(srcFile != NULL);
 
     /* for each frame */
     for ( ; ; ) {
         /* check magic number -> version */
         size_t const toRead = 4;
-        const BYTE* buf = (const BYTE*)ress.srcBuffer;
-        if (ress.srcBufferLoaded < toRead)
-            ress.srcBufferLoaded += fread((char*)ress.srcBuffer + ress.srcBufferLoaded, (size_t)1, toRead - ress.srcBufferLoaded, srcFile);
+        const BYTE* const buf = (const BYTE*)ress.srcBuffer;
+        if (ress.srcBufferLoaded < toRead)  /* load up to 4 bytes for header */
+            ress.srcBufferLoaded += fread((char*)ress.srcBuffer + ress.srcBufferLoaded,
+                                          (size_t)1, toRead - ress.srcBufferLoaded, srcFile);
         if (ress.srcBufferLoaded==0) {
-            if (readSomething==0) { DISPLAY("zstd: %s: unexpected end of file \n", srcFileName); fclose(srcFile); return 1; }  /* srcFileName is empty */
+            if (readSomething==0) {  /* srcFile is empty (which is invalid) */
+                DISPLAYLEVEL(1, "zstd: %s: unexpected end of file \n", srcFileName);
+                return 1;
+            }  /* else, just reached frame boundary */
             break;   /* no more input */
         }
-        readSomething = 1;   /* there is at least >= 4 bytes in srcFile */
-        if (ress.srcBufferLoaded < toRead) { DISPLAY("zstd: %s: unknown header \n", srcFileName); fclose(srcFile); return 1; }  /* srcFileName is empty */
-        if (buf[0] == 31 && buf[1] == 139) { /* gz magic number */
+        readSomething = 1;   /* there is at least 1 byte in srcFile */
+        if (ress.srcBufferLoaded < toRead) {
+            DISPLAYLEVEL(1, "zstd: %s: unknown header \n", srcFileName);
+            return 1;
+        }
+        if (ZSTD_isFrame(buf, ress.srcBufferLoaded)) {
+            unsigned long long const frameSize = FIO_decompressZstdFrame(&ress, srcFile, srcFileName, filesize);
+            if (frameSize == FIO_ERROR_FRAME_DECODING) return 1;
+            filesize += frameSize;
+        } else if (buf[0] == 31 && buf[1] == 139) { /* gz magic number */
 #ifdef ZSTD_GZDECOMPRESS
-            unsigned long long const result = FIO_decompressGzFrame(&ress, srcFile, srcFileName);
-            if (result == 0) return 1;
-            filesize += result;
+            unsigned long long const frameSize = FIO_decompressGzFrame(&ress, srcFile, srcFileName);
+            if (frameSize == FIO_ERROR_FRAME_DECODING) return 1;
+            filesize += frameSize;
 #else
-            DISPLAYLEVEL(1, "zstd: %s: gzip file cannot be uncompressed (zstd compiled without ZSTD_GZDECOMPRESS) -- ignored \n", srcFileName);
+            DISPLAYLEVEL(1, "zstd: %s: gzip file cannot be uncompressed (zstd compiled without HAVE_ZLIB) -- ignored \n", srcFileName);
             return 1;
 #endif
         } else if ((buf[0] == 0xFD && buf[1] == 0x37)  /* xz magic number */
                 || (buf[0] == 0x5D && buf[1] == 0x00)) { /* lzma header (no magic number) */
 #ifdef ZSTD_LZMADECOMPRESS
-            unsigned long long const result = FIO_decompressLzmaFrame(&ress, srcFile, srcFileName, buf[0] != 0xFD);
-            if (result == 0) return 1;
-            filesize += result;
+            unsigned long long const frameSize = FIO_decompressLzmaFrame(&ress, srcFile, srcFileName, buf[0] != 0xFD);
+            if (frameSize == FIO_ERROR_FRAME_DECODING) return 1;
+            filesize += frameSize;
 #else
-            DISPLAYLEVEL(1, "zstd: %s: xz/lzma file cannot be uncompressed (zstd compiled without ZSTD_LZMADECOMPRESS) -- ignored \n", srcFileName);
+            DISPLAYLEVEL(1, "zstd: %s: xz/lzma file cannot be uncompressed (zstd compiled without HAVE_LZMA) -- ignored \n", srcFileName);
             return 1;
 #endif
         } else if (MEM_readLE32(buf) == LZ4_MAGICNUMBER) {
 #ifdef ZSTD_LZ4DECOMPRESS
-            unsigned long long const result = FIO_decompressLz4Frame(&ress, srcFile, srcFileName);
-            if (result == 0) return 1;
-            filesize += result;
+            unsigned long long const frameSize = FIO_decompressLz4Frame(&ress, srcFile, srcFileName);
+            if (frameSize == FIO_ERROR_FRAME_DECODING) return 1;
+            filesize += frameSize;
 #else
-            DISPLAYLEVEL(1, "zstd: %s: lz4 file cannot be uncompressed (zstd compiled without ZSTD_LZ4DECOMPRESS) -- ignored \n", srcFileName);
+            DISPLAYLEVEL(1, "zstd: %s: lz4 file cannot be uncompressed (zstd compiled without HAVE_LZ4) -- ignored \n", srcFileName);
             return 1;
 #endif
+        } else if ((g_overwrite) && !strcmp (dstFileName, stdoutmark)) {  /* pass-through mode */
+            return FIO_passThrough(ress.dstFile, srcFile,
+                                   ress.srcBuffer, ress.srcBufferSize, ress.srcBufferLoaded);
         } else {
-            if (!ZSTD_isFrame(ress.srcBuffer, toRead)) {
-                if ((g_overwrite) && !strcmp (dstFileName, stdoutmark)) {  /* pass-through mode */
-                    unsigned const result = FIO_passThrough(ress.dstFile, srcFile, ress.srcBuffer, ress.srcBufferSize, ress.srcBufferLoaded);
-                    if (fclose(srcFile)) EXM_THROW(32, "zstd: %s close error", srcFileName);  /* error should never happen */
-                    return result;
-                } else {
-                    DISPLAYLEVEL(1, "zstd: %s: not in zstd format \n", srcFileName);
-                    fclose(srcFile);
-                    return 1;
-            }   }
-            filesize += FIO_decompressFrame(&ress, srcFile, filesize);
-        }
-    }
+            DISPLAYLEVEL(1, "zstd: %s: unsupported format \n", srcFileName);
+            return 1;
+    }   }  /* for each frame */
 
     /* Final Status */
     DISPLAYLEVEL(2, "\r%79s\r", "");
     DISPLAYLEVEL(2, "%-20s: %llu bytes \n", srcFileName, filesize);
 
-    /* Close file */
-    if (fclose(srcFile)) EXM_THROW(33, "zstd: %s close error", srcFileName);  /* error should never happen */
-    if (g_removeSrcFile /* --rm */ && strcmp(srcFileName, stdinmark)) { if (remove(srcFileName)) EXM_THROW(34, "zstd: %s: %s", srcFileName, strerror(errno)); };
     return 0;
 }
 
 
+/** FIO_decompressSrcFile() :
+    Decompression `srcFileName` into `ress.dstFile`
+    @return : 0 : OK
+              1 : operation not started
+*/
+static int FIO_decompressSrcFile(dRess_t ress, const char* dstFileName, const char* srcFileName)
+{
+    FILE* srcFile;
+    int result;
+
+    if (UTIL_isDirectory(srcFileName)) {
+        DISPLAYLEVEL(1, "zstd: %s is a directory -- ignored \n", srcFileName);
+        return 1;
+    }
+
+    srcFile = FIO_openSrcFile(srcFileName);
+    if (srcFile==NULL) return 1;
+
+    result = FIO_decompressFrames(ress, srcFile, dstFileName, srcFileName);
+
+    /* Close file */
+    if (fclose(srcFile)) {
+        DISPLAYLEVEL(1, "zstd: %s: %s \n", srcFileName, strerror(errno));  /* error should never happen */
+        return 1;
+    }
+    if ( g_removeSrcFile /* --rm */
+      && (result==0)   /* decompression successful */
+      && strcmp(srcFileName, stdinmark) ) /* not stdin */ {
+        if (remove(srcFileName)) {
+            /* failed to remove src file */
+            DISPLAYLEVEL(1, "zstd: %s: %s \n", srcFileName, strerror(errno));
+            return 1;
+    }   }
+    return result;
+}
+
+
 /** FIO_decompressFile_extRess() :
     decompress `srcFileName` into `dstFileName`
     @return : 0 : OK
@@ -1297,16 +1779,21 @@ static int FIO_decompressDstFile(dRess_t ress,
     ress.dstFile = FIO_openDstFile(dstFileName);
     if (ress.dstFile==0) return 1;
 
-    if (strcmp (srcFileName, stdinmark) && UTIL_getFileStat(srcFileName, &statbuf)) stat_result = 1;
+    if (strcmp (srcFileName, stdinmark) && UTIL_getFileStat(srcFileName, &statbuf))
+        stat_result = 1;
     result = FIO_decompressSrcFile(ress, dstFileName, srcFileName);
 
-    if (fclose(ress.dstFile)) EXM_THROW(38, "Write error : cannot properly close %s", dstFileName);
+    if (fclose(ress.dstFile)) {
+        DISPLAYLEVEL(1, "zstd: %s: %s \n", dstFileName, strerror(errno));
+        result = 1;
+    }
 
-    if ( (result != 0)
+    if ( (result != 0)  /* operation failure */
        && strcmp(dstFileName, nulmark)  /* special case : don't remove() /dev/null (#316) */
-       && remove(dstFileName) )
+       && remove(dstFileName) /* remove artefact */ )
         result=1;   /* don't do anything special if remove() fails */
-    else if (strcmp (dstFileName, stdoutmark) && stat_result) UTIL_setFileStat(dstFileName, &statbuf);
+    else if (strcmp (dstFileName, stdoutmark) && stat_result)
+        UTIL_setFileStat(dstFileName, &statbuf);
     return result;
 }
 
@@ -1314,13 +1801,12 @@ static int FIO_decompressDstFile(dRess_t ress,
 int FIO_decompressFilename(const char* dstFileName, const char* srcFileName,
                            const char* dictFileName)
 {
-    int missingFiles = 0;
-    dRess_t ress = FIO_createDResources(dictFileName);
+    dRess_t const ress = FIO_createDResources(dictFileName);
 
-    missingFiles += FIO_decompressDstFile(ress, dstFileName, srcFileName);
+    int const decodingError = FIO_decompressDstFile(ress, dstFileName, srcFileName);
 
     FIO_freeDResources(ress);
-    return missingFiles;
+    return decodingError;
 }
 
 
@@ -1333,7 +1819,8 @@ int FIO_decompressMultipleFilenames(const char** srcNamesTable, unsigned nbFiles
     int missingFiles = 0;
     dRess_t ress = FIO_createDResources(dictFileName);
 
-    if (suffix==NULL) EXM_THROW(70, "zstd: decompression: unknown dst");   /* should never happen */
+    if (suffix==NULL)
+        EXM_THROW(70, "zstd: decompression: unknown dst");   /* should never happen */
 
     if (!strcmp(suffix, stdoutmark) || !strcmp(suffix, nulmark)) {  /* special cases : -c or -t */
         unsigned u;
@@ -1341,19 +1828,22 @@ int FIO_decompressMultipleFilenames(const char** srcNamesTable, unsigned nbFiles
         if (ress.dstFile == 0) EXM_THROW(71, "cannot open %s", suffix);
         for (u=0; u<nbFiles; u++)
             missingFiles += FIO_decompressSrcFile(ress, suffix, srcNamesTable[u]);
-        if (fclose(ress.dstFile)) EXM_THROW(72, "Write error : cannot properly close stdout");
+        if (fclose(ress.dstFile))
+            EXM_THROW(72, "Write error : cannot properly close stdout");
     } else {
         size_t suffixSize;
         size_t dfnSize = FNSPACE;
         unsigned u;
         char* dstFileName = (char*)malloc(FNSPACE);
-        if (dstFileName==NULL) EXM_THROW(73, "not enough memory for dstFileName");
+        if (dstFileName==NULL)
+            EXM_THROW(73, "not enough memory for dstFileName");
         for (u=0; u<nbFiles; u++) {   /* create dstFileName */
             const char* const srcFileName = srcNamesTable[u];
             const char* const suffixPtr = strrchr(srcFileName, '.');
             size_t const sfnSize = strlen(srcFileName);
             if (!suffixPtr) {
-                DISPLAYLEVEL(1, "zstd: %s: unknown suffix -- ignored \n", srcFileName);
+                DISPLAYLEVEL(1, "zstd: %s: unknown suffix -- ignored \n",
+                                srcFileName);
                 skippedFiles++;
                 continue;
             }
@@ -1362,17 +1852,23 @@ int FIO_decompressMultipleFilenames(const char** srcNamesTable, unsigned nbFiles
                 free(dstFileName);
                 dfnSize = sfnSize + 20;
                 dstFileName = (char*)malloc(dfnSize);
-                if (dstFileName==NULL) EXM_THROW(74, "not enough memory for dstFileName");
+                if (dstFileName==NULL)
+                    EXM_THROW(74, "not enough memory for dstFileName");
             }
-            if (sfnSize <= suffixSize || (strcmp(suffixPtr, GZ_EXTENSION) && strcmp(suffixPtr, XZ_EXTENSION) && strcmp(suffixPtr, ZSTD_EXTENSION) && strcmp(suffixPtr, LZMA_EXTENSION) && strcmp(suffixPtr, LZ4_EXTENSION))) {
-                DISPLAYLEVEL(1, "zstd: %s: unknown suffix (%s/%s/%s/%s expected) -- ignored \n", srcFileName, GZ_EXTENSION, XZ_EXTENSION, ZSTD_EXTENSION, LZMA_EXTENSION);
+            if (sfnSize <= suffixSize
+                || (strcmp(suffixPtr, GZ_EXTENSION)
+                    && strcmp(suffixPtr, XZ_EXTENSION)
+                    && strcmp(suffixPtr, ZSTD_EXTENSION)
+                    && strcmp(suffixPtr, LZMA_EXTENSION)
+                    && strcmp(suffixPtr, LZ4_EXTENSION)) ) {
+                DISPLAYLEVEL(1, "zstd: %s: unknown suffix (%s/%s/%s/%s/%s expected) -- ignored \n",
+                             srcFileName, GZ_EXTENSION, XZ_EXTENSION, ZSTD_EXTENSION, LZMA_EXTENSION, LZ4_EXTENSION);
                 skippedFiles++;
                 continue;
             } else {
                 memcpy(dstFileName, srcFileName, sfnSize - suffixSize);
                 dstFileName[sfnSize-suffixSize] = '\0';
             }
-
             missingFiles += FIO_decompressDstFile(ress, dstFileName, srcFileName);
         }
         free(dstFileName);
diff --git a/programs/fileio.h b/programs/fileio.h
index 65da98d7fa88..9d9167df9ef5 100644
--- a/programs/fileio.h
+++ b/programs/fileio.h
@@ -70,6 +70,7 @@ int FIO_compressFilename (const char* outfilename, const char* infilename, const
     @return : 0 == ok;  1 == pb with src file. */
 int FIO_decompressFilename (const char* outfilename, const char* infilename, const char* dictFileName);
 
+int FIO_listMultipleFiles(unsigned numFiles, const char** filenameTable, int displayLevel);
 
 /*-*************************************
 *  Multiple File functions
diff --git a/programs/util.h b/programs/util.h
index 5f437b2b268c..dd971e0f884b 100644
--- a/programs/util.h
+++ b/programs/util.h
@@ -208,7 +208,7 @@ UTIL_STATIC int UTIL_getFileStat(const char* infilename, stat_t *statbuf)
 }
 
 
-UTIL_STATIC int UTIL_isRegFile(const char* infilename)
+UTIL_STATIC int UTIL_isRegularFile(const char* infilename)
 {
     stat_t statbuf;
     return UTIL_getFileStat(infilename, &statbuf); /* Only need to know whether it is a regular file */
@@ -609,7 +609,7 @@ UTIL_STATIC int UTIL_countPhysicalCores(void)
 
     /* try to determine if there's hyperthreading */
     {   FILE* const cpuinfo = fopen("/proc/cpuinfo", "r");
-        size_t const BUF_SIZE = 80;
+#define BUF_SIZE 80
         char buff[BUF_SIZE];
 
         int siblings = 0;
diff --git a/programs/zstd.1 b/programs/zstd.1
index 6cc5f7e9d2f6..5df45db2153e 100644
--- a/programs/zstd.1
+++ b/programs/zstd.1
@@ -1,5 +1,5 @@
 .
-.TH "ZSTD" "1" "May 2017" "zstd 1.2.0" "User Commands"
+.TH "ZSTD" "1" "June 2017" "zstd 1.3.0" "User Commands"
 .
 .SH "NAME"
 \fBzstd\fR \- zstd, zstdmt, unzstd, zstdcat \- Compress or decompress \.zst files
@@ -89,6 +89,10 @@ Benchmark file(s) using compression level #
 \fB\-\-train FILEs\fR
 Use FILEs as a training set to create a dictionary\. The training set should contain a lot of small files (> 100)\.
 .
+.TP
+\fB\-l\fR, \fB\-\-list\fR
+Display information related to a zstd compressed file, such as size, ratio, and checksum\. Some of these fields may not be available\. This command can be augmented with the \fB\-v\fR modifier\.
+.
 .SS "Operation modifiers"
 .
 .TP
@@ -235,8 +239,8 @@ benchmark file(s) using multiple compression levels, from \fB\-b#\fR to \fB\-e#\
 minimum evaluation time, in seconds (default : 3s), benchmark mode only
 .
 .TP
-\fB\-B#\fR
-cut file into independent blocks of size # (default: no block)
+\fB\-B#\fR, \fB\-\-block\-size=#\fR
+cut file(s) into independent blocks of size # (default: no block)
 .
 .TP
 \fB\-\-priority=rt\fR
@@ -252,7 +256,7 @@ set process priority to real\-time
 Specify a strategy used by a match finder\.
 .
 .IP
-There are 8 strategies numbered from 0 to 7, from faster to stronger: 0=ZSTD_fast, 1=ZSTD_dfast, 2=ZSTD_greedy, 3=ZSTD_lazy, 4=ZSTD_lazy2, 5=ZSTD_btlazy2, 6=ZSTD_btopt, 7=ZSTD_btopt2\.
+There are 8 strategies numbered from 1 to 8, from faster to stronger: 1=ZSTD_fast, 2=ZSTD_dfast, 3=ZSTD_greedy, 4=ZSTD_lazy, 5=ZSTD_lazy2, 6=ZSTD_btlazy2, 7=ZSTD_btopt, 8=ZSTD_btultra\.
 .
 .TP
 \fBwindowLog\fR=\fIwlog\fR, \fBwlog\fR=\fIwlog\fR
@@ -306,7 +310,7 @@ The minimum \fIslen\fR is 3 and the maximum is 7\.
 Specify the minimum match length that causes a match finder to stop searching for better matches\.
 .
 .IP
-A larger minimum match length usually improves compression ratio but decreases compression speed\. This option is only used with strategies ZSTD_btopt and ZSTD_btopt2\.
+A larger minimum match length usually improves compression ratio but decreases compression speed\. This option is only used with strategies ZSTD_btopt and ZSTD_btultra\.
 .
 .IP
 The minimum \fItlen\fR is 4 and the maximum is 999\.
diff --git a/programs/zstd.1.md b/programs/zstd.1.md
index 118c9f2f8ee5..24e25a2f3af1 100644
--- a/programs/zstd.1.md
+++ b/programs/zstd.1.md
@@ -93,6 +93,10 @@ the last one takes effect.
 * `--train FILEs`:
     Use FILEs as a training set to create a dictionary.
     The training set should contain a lot of small files (> 100).
+* `-l`, `--list`:
+    Display information related to a zstd compressed file, such as size, ratio, and checksum.
+    Some of these fields may not be available.
+    This command can be augmented with the `-v` modifier.
 
 ### Operation modifiers
 
@@ -230,8 +234,8 @@ BENCHMARK
     benchmark file(s) using multiple compression levels, from `-b#` to `-e#` (inclusive)
 * `-i#`:
     minimum evaluation time, in seconds (default : 3s), benchmark mode only
-* `-B#`:
-    cut file into independent blocks of size # (default: no block)
+* `-B#`, `--block-size=#`:
+    cut file(s) into independent blocks of size # (default: no block)
 * `--priority=rt`:
     set process priority to real-time
 
@@ -250,9 +254,9 @@ The list of available _options_:
 - `strategy`=_strat_, `strat`=_strat_:
     Specify a strategy used by a match finder.
 
-    There are 8 strategies numbered from 0 to 7, from faster to stronger:
-    0=ZSTD\_fast, 1=ZSTD\_dfast, 2=ZSTD\_greedy, 3=ZSTD\_lazy,
-    4=ZSTD\_lazy2, 5=ZSTD\_btlazy2, 6=ZSTD\_btopt, 7=ZSTD\_btopt2.
+    There are 8 strategies numbered from 1 to 8, from faster to stronger:
+    1=ZSTD\_fast, 2=ZSTD\_dfast, 3=ZSTD\_greedy, 4=ZSTD\_lazy,
+    5=ZSTD\_lazy2, 6=ZSTD\_btlazy2, 7=ZSTD\_btopt, 8=ZSTD\_btultra.
 
 - `windowLog`=_wlog_, `wlog`=_wlog_:
     Specify the maximum number of bits for a match distance.
@@ -304,7 +308,7 @@ The list of available _options_:
 
     A larger minimum match length usually improves compression ratio but
     decreases compression speed.
-    This option is only used with strategies ZSTD_btopt and ZSTD_btopt2.
+    This option is only used with strategies ZSTD_btopt and ZSTD_btultra.
 
     The minimum _tlen_ is 4 and the maximum is 999.
 
diff --git a/programs/zstdcli.c b/programs/zstdcli.c
index 32fef99930e9..35772e0a7140 100644
--- a/programs/zstdcli.c
+++ b/programs/zstdcli.c
@@ -56,7 +56,9 @@
 #define ZSTD_GUNZIP "gunzip"
 #define ZSTD_GZCAT "gzcat"
 #define ZSTD_LZMA "lzma"
+#define ZSTD_UNLZMA "unlzma"
 #define ZSTD_XZ "xz"
+#define ZSTD_UNXZ "unxz"
 
 #define KB *(1 <<10)
 #define MB *(1 <<20)
@@ -117,6 +119,7 @@ static int usage_advanced(const char* programName)
     DISPLAY( " -v     : verbose mode; specify multiple times to increase verbosity\n");
     DISPLAY( " -q     : suppress warnings; specify twice to suppress errors too\n");
     DISPLAY( " -c     : force write to standard output, even if it is the console\n");
+    DISPLAY( " -l     : print information about zstd compressed files.\n");
 #ifndef ZSTD_NOCOMPRESS
     DISPLAY( "--ultra : enable levels beyond %i, up to %i (requires more memory)\n", ZSTDCLI_CLEVEL_MAX, ZSTD_maxCLevel());
 #ifdef ZSTD_MULTITHREAD
@@ -148,6 +151,7 @@ static int usage_advanced(const char* programName)
 #endif
 #endif
     DISPLAY( " -M#    : Set a memory usage limit for decompression \n");
+    DISPLAY( "--list  : list information about a zstd compressed file \n");
     DISPLAY( "--      : All arguments after \"--\" are treated as files \n");
 #ifndef ZSTD_NODICT
     DISPLAY( "\n");
@@ -244,7 +248,7 @@ static unsigned longCommandWArg(const char** stringPtr, const char* longCommand)
  * @return 1 means that cover parameters were correct
  * @return 0 in case of malformed parameters
  */
-static unsigned parseCoverParameters(const char* stringPtr, COVER_params_t* params)
+static unsigned parseCoverParameters(const char* stringPtr, ZDICT_cover_params_t* params)
 {
     memset(params, 0, sizeof(*params));
     for (; ;) {
@@ -273,9 +277,9 @@ static unsigned parseLegacyParameters(const char* stringPtr, unsigned* selectivi
     return 1;
 }
 
-static COVER_params_t defaultCoverParams(void)
+static ZDICT_cover_params_t defaultCoverParams(void)
 {
-    COVER_params_t params;
+    ZDICT_cover_params_t params;
     memset(&params, 0, sizeof(params));
     params.d = 8;
     params.steps = 4;
@@ -298,7 +302,7 @@ static unsigned parseCompressionParameters(const char* stringPtr, ZSTD_compressi
         if (longCommandWArg(&stringPtr, "searchLog=") || longCommandWArg(&stringPtr, "slog=")) { params->searchLog = readU32FromChar(&stringPtr); if (stringPtr[0]==',') { stringPtr++; continue; } else break; }
         if (longCommandWArg(&stringPtr, "searchLength=") || longCommandWArg(&stringPtr, "slen=")) { params->searchLength = readU32FromChar(&stringPtr); if (stringPtr[0]==',') { stringPtr++; continue; } else break; }
         if (longCommandWArg(&stringPtr, "targetLength=") || longCommandWArg(&stringPtr, "tlen=")) { params->targetLength = readU32FromChar(&stringPtr); if (stringPtr[0]==',') { stringPtr++; continue; } else break; }
-        if (longCommandWArg(&stringPtr, "strategy=") || longCommandWArg(&stringPtr, "strat=")) { params->strategy = (ZSTD_strategy)(1 + readU32FromChar(&stringPtr)); if (stringPtr[0]==',') { stringPtr++; continue; } else break; }
+        if (longCommandWArg(&stringPtr, "strategy=") || longCommandWArg(&stringPtr, "strat=")) { params->strategy = (ZSTD_strategy)(readU32FromChar(&stringPtr)); if (stringPtr[0]==',') { stringPtr++; continue; } else break; }
         if (longCommandWArg(&stringPtr, "overlapLog=") || longCommandWArg(&stringPtr, "ovlog=")) { g_overlapLog = readU32FromChar(&stringPtr); if (stringPtr[0]==',') { stringPtr++; continue; } else break; }
         return 0;
     }
@@ -310,7 +314,7 @@ static unsigned parseCompressionParameters(const char* stringPtr, ZSTD_compressi
 }
 
 
-typedef enum { zom_compress, zom_decompress, zom_test, zom_bench, zom_train } zstd_operation_mode;
+typedef enum { zom_compress, zom_decompress, zom_test, zom_bench, zom_train, zom_list } zstd_operation_mode;
 
 #define CLEAN_RETURN(i) { operationResult = (i); goto _end; }
 
@@ -354,7 +358,7 @@ int main(int argCount, const char* argv[])
     unsigned fileNamesNb;
 #endif
 #ifndef ZSTD_NODICT
-    COVER_params_t coverParams = defaultCoverParams();
+    ZDICT_cover_params_t coverParams = defaultCoverParams();
     int cover = 1;
 #endif
 
@@ -377,7 +381,9 @@ int main(int argCount, const char* argv[])
     if (exeNameMatch(programName, ZSTD_GUNZIP)) { operation=zom_decompress; FIO_setRemoveSrcFile(1); }                                          /* behave like gunzip */
     if (exeNameMatch(programName, ZSTD_GZCAT)) { operation=zom_decompress; forceStdout=1; FIO_overwriteMode(); outFileName=stdoutmark; g_displayLevel=1; }  /* behave like gzcat */
     if (exeNameMatch(programName, ZSTD_LZMA)) { suffix = LZMA_EXTENSION; FIO_setCompressionType(FIO_lzmaCompression); FIO_setRemoveSrcFile(1); }    /* behave like lzma */
+    if (exeNameMatch(programName, ZSTD_UNLZMA)) { operation=zom_decompress; FIO_setCompressionType(FIO_lzmaCompression); FIO_setRemoveSrcFile(1); }    /* behave like unlzma */
     if (exeNameMatch(programName, ZSTD_XZ)) { suffix = XZ_EXTENSION; FIO_setCompressionType(FIO_xzCompression); FIO_setRemoveSrcFile(1); }    /* behave like xz */
+    if (exeNameMatch(programName, ZSTD_UNXZ)) { operation=zom_decompress; FIO_setCompressionType(FIO_xzCompression); FIO_setRemoveSrcFile(1); }    /* behave like unxz */
     memset(&compressionParams, 0, sizeof(compressionParams));
 
     /* command switches */
@@ -401,6 +407,7 @@ int main(int argCount, const char* argv[])
                 if (argument[1]=='-') {
                     /* long commands (--long-word) */
                     if (!strcmp(argument, "--")) { nextArgumentsAreFiles=1; continue; }   /* only file names allowed from now on */
+                    if (!strcmp(argument, "--list")) { operation=zom_list; continue; }
                     if (!strcmp(argument, "--compress")) { operation=zom_compress; continue; }
                     if (!strcmp(argument, "--decompress")) { operation=zom_decompress; continue; }
                     if (!strcmp(argument, "--uncompress")) { operation=zom_decompress; continue; }
@@ -531,7 +538,7 @@ int main(int argCount, const char* argv[])
                         argument++;
                         memLimit = readU32FromChar(&argument);
                         break;
-
+                    case 'l': operation=zom_list; argument++; break;
 #ifdef UTIL_HAS_CREATEFILELIST
                         /* recursive */
                     case 'r': recursive=1; argument++; break;
@@ -672,7 +679,10 @@ int main(int argCount, const char* argv[])
         }
     }
 #endif
-
+    if (operation == zom_list) {
+        int const ret = FIO_listMultipleFiles(filenameIdx, filenameTable, g_displayLevel);
+        CLEAN_RETURN(ret);
+    }
     /* Check if benchmark is selected */
     if (operation==zom_bench) {
 #ifndef ZSTD_NOBENCH
@@ -689,20 +699,20 @@ int main(int argCount, const char* argv[])
     /* Check if dictionary builder is selected */
     if (operation==zom_train) {
 #ifndef ZSTD_NODICT
+        ZDICT_params_t zParams;
+        zParams.compressionLevel = dictCLevel;
+        zParams.notificationLevel = g_displayLevel;
+        zParams.dictID = dictID;
         if (cover) {
             int const optimize = !coverParams.k || !coverParams.d;
             coverParams.nbThreads = nbThreads;
-            coverParams.compressionLevel = dictCLevel;
-            coverParams.notificationLevel = g_displayLevel;
-            coverParams.dictID = dictID;
+            coverParams.zParams = zParams;
             operationResult = DiB_trainFromFiles(outFileName, maxDictSize, filenameTable, filenameIdx, NULL, &coverParams, optimize);
         } else {
-            ZDICT_params_t dictParams;
+            ZDICT_legacy_params_t dictParams;
             memset(&dictParams, 0, sizeof(dictParams));
-            dictParams.compressionLevel = dictCLevel;
             dictParams.selectivityLevel = dictSelect;
-            dictParams.notificationLevel = g_displayLevel;
-            dictParams.dictID = dictID;
+            dictParams.zParams = zParams;
             operationResult = DiB_trainFromFiles(outFileName, maxDictSize, filenameTable, filenameIdx, &dictParams, NULL, 0);
         }
 #endif
diff --git a/tests/Makefile b/tests/Makefile
index ea58c0fe5119..82f12887bf9b 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -25,17 +25,18 @@ PRGDIR  = ../programs
 PYTHON ?= python3
 TESTARTEFACT := versionsTest namespaceTest
 
-
-DEBUGFLAGS=-g -DZSTD_DEBUG=1
-CPPFLAGS+= -I$(ZSTDDIR) -I$(ZSTDDIR)/common -I$(ZSTDDIR)/compress \
-           -I$(ZSTDDIR)/dictBuilder -I$(ZSTDDIR)/deprecated -I$(PRGDIR) \
-           $(DEBUGFLAG)
-CFLAGS  ?= -O3
-CFLAGS  += -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
-           -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
-           -Wstrict-prototypes -Wundef -Wformat-security
-CFLAGS  += $(MOREFLAGS)
-FLAGS    = $(CPPFLAGS) $(CFLAGS) $(LDFLAGS)
+DEBUGLEVEL= 1
+DEBUGFLAGS= -g -DZSTD_DEBUG=$(DEBUGLEVEL)
+CPPFLAGS += -I$(ZSTDDIR) -I$(ZSTDDIR)/common -I$(ZSTDDIR)/compress \
+            -I$(ZSTDDIR)/dictBuilder -I$(ZSTDDIR)/deprecated -I$(PRGDIR)
+CFLAGS   ?= -O3
+CFLAGS   += -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow                 \
+            -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
+            -Wstrict-prototypes -Wundef -Wformat-security                   \
+            -Wvla -Wformat=2 -Winit-self -Wfloat-equal -Wwrite-strings      \
+            -Wredundant-decls
+CFLAGS   += $(DEBUGFLAGS) $(MOREFLAGS)
+FLAGS     = $(CPPFLAGS) $(CFLAGS) $(LDFLAGS)
 
 
 ZSTDCOMMON_FILES := $(ZSTDDIR)/common/*.c
@@ -92,11 +93,12 @@ zstd-nolegacy:
 gzstd:
 	$(MAKE) -C $(PRGDIR) $@
 
-fullbench  : $(ZSTD_FILES) $(PRGDIR)/datagen.c fullbench.c
-	$(CC)      $(FLAGS) $^ -o $@$(EXT)
-
-fullbench32 : $(ZSTD_FILES) $(PRGDIR)/datagen.c fullbench.c
-	$(CC)  -m32  $(FLAGS) $^ -o $@$(EXT)
+fullbench32: CPPFLAGS += -m32
+fullbench fullbench32 : CPPFLAGS += $(MULTITHREAD_CPP)
+fullbench fullbench32 : LDFLAGS += $(MULTITHREAD_LD)
+fullbench fullbench32 : DEBUGFLAGS =   # turn off assert() for speed measurements
+fullbench fullbench32 : $(ZSTD_FILES) $(PRGDIR)/datagen.c fullbench.c
+	$(CC) $(FLAGS) $^ -o $@$(EXT)
 
 fullbench-lib: $(PRGDIR)/datagen.c fullbench.c
 	$(MAKE) -C $(ZSTDDIR) libzstd.a
@@ -157,7 +159,7 @@ zstreamtest-dll : $(ZSTDDIR)/common/xxhash.c $(PRGDIR)/datagen.c zstreamtest.c
 	$(MAKE) -C $(ZSTDDIR) libzstd
 	$(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@$(EXT)
 
-paramgrill : DEBUGFLAG =
+paramgrill : DEBUGFLAGS =
 paramgrill : $(ZSTD_FILES) $(PRGDIR)/datagen.c paramgrill.c
 	$(CC)      $(FLAGS) $^ -lm -o $@$(EXT)
 
@@ -178,7 +180,7 @@ legacy : CPPFLAGS+= -I$(ZSTDDIR)/legacy
 legacy : $(ZSTD_FILES) $(wildcard $(ZSTDDIR)/legacy/*.c) legacy.c
 	$(CC)      $(FLAGS) $^ -o $@$(EXT)
 
-decodecorpus	: $(filter-out $(ZSTDDIR)/compress/zstd_compress.c, $(wildcard $(ZSTD_FILES))) decodecorpus.c
+decodecorpus	: $(filter-out $(ZSTDDIR)/compress/zstd_compress.c, $(wildcard $(ZSTD_FILES))) $(ZDICT_FILES) decodecorpus.c
 	$(CC)      $(FLAGS) $^ -o $@$(EXT) -lm
 
 symbols  : symbols.c
@@ -222,7 +224,7 @@ clean:
 ifneq (,$(filter $(shell uname),Linux Darwin GNU/kFreeBSD GNU OpenBSD FreeBSD NetBSD DragonFly SunOS))
 HOST_OS = POSIX
 
-valgrindTest: VALGRIND = valgrind --leak-check=full --error-exitcode=1
+valgrindTest: VALGRIND = valgrind --leak-check=full --show-leak-kinds=all --error-exitcode=1
 valgrindTest: zstd datagen fuzzer fullbench
 	@echo "\n ---- valgrind tests : memory analyzer ----"
 	$(VALGRIND) ./datagen -g50M > $(VOID)
@@ -270,7 +272,7 @@ endif
 
 test32: test-zstd32 test-fullbench32 test-fuzzer32 test-zstream32
 
-test-all: test test32 valgrindTest
+test-all: test test32 valgrindTest test-decodecorpus-cli
 
 test-zstd: ZSTD = $(PRGDIR)/zstd
 test-zstd: zstd zstd-playTests
@@ -319,6 +321,8 @@ test-zbuff32: zbufftest32
 
 test-zstream: zstreamtest
 	$(QEMU_SYS) ./zstreamtest $(ZSTREAM_TESTTIME) $(FUZZER_FLAGS)
+	$(QEMU_SYS) ./zstreamtest --mt $(ZSTREAM_TESTTIME) $(FUZZER_FLAGS)
+	$(QEMU_SYS) ./zstreamtest --newapi $(ZSTREAM_TESTTIME) $(FUZZER_FLAGS)
 
 test-zstream32: zstreamtest32
 	$(QEMU_SYS) ./zstreamtest32 $(ZSTREAM_TESTTIME) $(FUZZER_FLAGS)
@@ -338,6 +342,39 @@ test-legacy: legacy
 test-decodecorpus: decodecorpus
 	$(QEMU_SYS) ./decodecorpus -t $(DECODECORPUS_TESTTIME)
 
+test-decodecorpus-cli: decodecorpus
+	@echo "\n ---- decodecorpus basic cli tests ----"
+	@mkdir testdir
+	./decodecorpus -n5 -otestdir -ptestdir
+	@cd testdir && \
+	$(ZSTD) -d z000000.zst -o tmp0 && \
+	$(ZSTD) -d z000001.zst -o tmp1 && \
+	$(ZSTD) -d z000002.zst -o tmp2 && \
+	$(ZSTD) -d z000003.zst -o tmp3 && \
+	$(ZSTD) -d z000004.zst -o tmp4 && \
+	diff z000000 tmp0 && \
+	diff z000001 tmp1 && \
+	diff z000002 tmp2 && \
+	diff z000003 tmp3 && \
+	diff z000004 tmp4 && \
+	rm ./* && \
+	cd ..
+	@echo "\n ---- decodecorpus dictionary cli tests ----"
+	./decodecorpus -n5 -otestdir -ptestdir --use-dict=1MB
+	@cd testdir && \
+	$(ZSTD) -d z000000.zst -D dictionary -o tmp0 && \
+	$(ZSTD) -d z000001.zst -D dictionary -o tmp1 && \
+	$(ZSTD) -d z000002.zst -D dictionary -o tmp2 && \
+	$(ZSTD) -d z000003.zst -D dictionary -o tmp3 && \
+	$(ZSTD) -d z000004.zst -D dictionary -o tmp4 && \
+	diff z000000 tmp0 && \
+	diff z000001 tmp1 && \
+	diff z000002 tmp2 && \
+	diff z000003 tmp3 && \
+	diff z000004 tmp4 && \
+	cd ..
+	@rm -rf testdir
+
 test-pool: pool
 	$(QEMU_SYS) ./pool
 
diff --git a/tests/datagencli.c b/tests/datagencli.c
index 2f3ebc4d6863..8a81939d16de 100644
--- a/tests/datagencli.c
+++ b/tests/datagencli.c
@@ -48,7 +48,8 @@ static int usage(const char* programName)
     DISPLAY( "Arguments :\n");
     DISPLAY( " -g#    : generate # data (default:%i)\n", SIZE_DEFAULT);
     DISPLAY( " -s#    : Select seed (default:%i)\n", SEED_DEFAULT);
-    DISPLAY( " -P#    : Select compressibility in %% (default:%i%%)\n", COMPRESSIBILITY_DEFAULT);
+    DISPLAY( " -P#    : Select compressibility in %% (default:%i%%)\n",
+                        COMPRESSIBILITY_DEFAULT);
     DISPLAY( " -h     : display help and exit\n");
     return 0;
 }
@@ -56,7 +57,7 @@ static int usage(const char* programName)
 
 int main(int argc, const char** argv)
 {
-    double proba = (double)COMPRESSIBILITY_DEFAULT / 100;
+    unsigned probaU32 = COMPRESSIBILITY_DEFAULT;
     double litProba = 0.0;
     U64 size = SIZE_DEFAULT;
     U32 seed = SEED_DEFAULT;
@@ -94,11 +95,10 @@ int main(int argc, const char** argv)
                     break;
                 case 'P':
                     argument++;
-                    proba=0.0;
+                    probaU32 = 0;
                     while ((*argument>='0') && (*argument<='9'))
-                        proba *= 10, proba += *argument++ - '0';
-                    if (proba>100.) proba=100.;
-                    proba /= 100.;
+                        probaU32 *= 10, probaU32 += *argument++ - '0';
+                    if (probaU32>100) probaU32 = 100;
                     break;
                 case 'L':   /* hidden argument : Literal distribution probability */
                     argument++;
@@ -117,11 +117,12 @@ int main(int argc, const char** argv)
                 }
     }   }   }   /* for(argNb=1; argNb<argc; argNb++) */
 
-    DISPLAYLEVEL(4, "Data Generator \n");
+    DISPLAYLEVEL(4, "Compressible data Generator \n");
+    if (probaU32!=COMPRESSIBILITY_DEFAULT)
+        DISPLAYLEVEL(3, "Compressibility : %i%%\n", probaU32);
     DISPLAYLEVEL(3, "Seed = %u \n", seed);
-    if (proba!=COMPRESSIBILITY_DEFAULT) DISPLAYLEVEL(3, "Compressibility : %i%%\n", (U32)(proba*100));
 
-    RDG_genStdout(size, proba, litProba, seed);
+    RDG_genStdout(size, (double)probaU32/100, litProba, seed);
     DISPLAYLEVEL(1, "\n");
 
     return 0;
diff --git a/tests/decodecorpus.c b/tests/decodecorpus.c
index f7b3c854fdb2..eaf07457894f 100644
--- a/tests/decodecorpus.c
+++ b/tests/decodecorpus.c
@@ -18,6 +18,8 @@
 #include "zstd.h"
 #include "zstd_internal.h"
 #include "mem.h"
+#define ZDICT_STATIC_LINKING_ONLY
+#include "zdict.h"
 
 // Direct access to internal compression functions is required
 #include "zstd_compress.c"
@@ -73,8 +75,6 @@ static clock_t clockSpan(clock_t cStart)
 /*-*******************************************************
 *  Random function
 *********************************************************/
-#define CLAMP(x, a, b) ((x) < (a) ? (a) : ((x) > (b) ? (b) : (x)))
-
 static unsigned RAND(unsigned* src)
 {
 #define RAND_rotl32(x,r) ((x << r) | (x >> (32 - r)))
@@ -231,6 +231,12 @@ typedef struct {
     cblockStats_t oldStats; /* so they can be rolled back if uncompressible */
 } frame_t;
 
+typedef struct {
+    int useDict;
+    U32 dictID;
+    size_t dictContentSize;
+    BYTE* dictContent;
+} dictInfo;
 /*-*******************************************************
 *  Generator Functions
 *********************************************************/
@@ -240,7 +246,7 @@ struct {
 } opts; /* advanced options on generation */
 
 /* Generate and write a random frame header */
-static void writeFrameHeader(U32* seed, frame_t* frame)
+static void writeFrameHeader(U32* seed, frame_t* frame, dictInfo info)
 {
     BYTE* const op = frame->data;
     size_t pos = 0;
@@ -306,15 +312,26 @@ static void writeFrameHeader(U32* seed, frame_t* frame)
     pos += 4;
 
     {
+        /*
+         * fcsCode: 2-bit flag specifying how many bytes used to represent Frame_Content_Size (bits 7-6)
+         * singleSegment: 1-bit flag describing if data must be regenerated within a single continuous memory segment. (bit 5)
+         * contentChecksumFlag: 1-bit flag that is set if frame includes checksum at the end -- set to 1 below (bit 2)
+         * dictBits: 2-bit flag describing how many bytes Dictionary_ID uses -- set to 3 (bits 1-0)
+         * For more information: https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#frame_header
+         */
+        int const dictBits = info.useDict ? 3 : 0;
         BYTE const frameHeaderDescriptor =
-                (BYTE) ((fcsCode << 6) | (singleSegment << 5) | (1 << 2));
+                (BYTE) ((fcsCode << 6) | (singleSegment << 5) | (1 << 2) | dictBits);
         op[pos++] = frameHeaderDescriptor;
     }
 
     if (!singleSegment) {
         op[pos++] = windowByte;
     }
-
+    if (info.useDict) {
+        MEM_writeLE32(op + pos, (U32) info.dictID);
+        pos += 4;
+    }
     if (contentSizeFlag) {
         switch (fcsCode) {
         default: /* Impossible */
@@ -605,7 +622,7 @@ static inline void initSeqStore(seqStore_t *seqStore) {
 
 /* Randomly generate sequence commands */
 static U32 generateSequences(U32* seed, frame_t* frame, seqStore_t* seqStore,
-                                size_t contentSize, size_t literalsSize)
+                                size_t contentSize, size_t literalsSize, dictInfo info)
 {
     /* The total length of all the matches */
     size_t const remainingMatch = contentSize - literalsSize;
@@ -629,7 +646,6 @@ static U32 generateSequences(U32* seed, frame_t* frame, seqStore_t* seqStore,
     }
 
     DISPLAYLEVEL(5, "    total match lengths: %u\n", (U32)remainingMatch);
-
     for (i = 0; i < numSequences; i++) {
         /* Generate match and literal lengths by exponential distribution to
          * ensure nice numbers */
@@ -654,14 +670,33 @@ static U32 generateSequences(U32* seed, frame_t* frame, seqStore_t* seqStore,
 
         memcpy(srcPtr, literals, literalLen);
         srcPtr += literalLen;
-
         do {
             if (RAND(seed) & 7) {
                 /* do a normal offset */
+                U32 const dataDecompressed = (U32)((BYTE*)srcPtr-(BYTE*)frame->srcStart);
                 offset = (RAND(seed) %
                           MIN(frame->header.windowSize,
                               (size_t)((BYTE*)srcPtr - (BYTE*)frame->srcStart))) +
                          1;
+                if (info.useDict && (RAND(seed) & 1) && i + 1 != numSequences && dataDecompressed < frame->header.windowSize) {
+                    /* need to occasionally generate offsets that go past the start */
+                    /* including i+1 != numSequences because the last sequences has to adhere to predetermined contentSize */
+                    U32 lenPastStart = (RAND(seed) % info.dictContentSize) + 1;
+                    offset = (U32)((BYTE*)srcPtr - (BYTE*)frame->srcStart)+lenPastStart;
+                    if (offset > frame->header.windowSize) {
+                        if (lenPastStart < MIN_SEQ_LEN) {
+                            /* when offset > windowSize, matchLen bound by end of dictionary (lenPastStart) */
+                            /* this also means that lenPastStart must be greater than MIN_SEQ_LEN */
+                            /* make sure lenPastStart does not go past dictionary start though */
+                            lenPastStart = MIN(lenPastStart+MIN_SEQ_LEN, (U32)info.dictContentSize);
+                            offset = (U32)((BYTE*)srcPtr - (BYTE*)frame->srcStart) + lenPastStart;
+                        }
+                        {
+                            U32 const matchLenBound = MIN(frame->header.windowSize, lenPastStart);
+                            matchLen = MIN(matchLen, matchLenBound);
+                        }
+                    }
+                }
                 offsetCode = offset + ZSTD_REP_MOVE;
                 repIndex = 2;
             } else {
@@ -677,11 +712,20 @@ static U32 generateSequences(U32* seed, frame_t* frame, seqStore_t* seqStore,
                     repIndex = MIN(2, offsetCode + 1);
                 }
             }
-        } while (offset > (size_t)((BYTE*)srcPtr - (BYTE*)frame->srcStart) || offset == 0);
+        } while (((!info.useDict) && (offset > (size_t)((BYTE*)srcPtr - (BYTE*)frame->srcStart))) || offset == 0);
 
-        {   size_t j;
+        {
+            size_t j;
+            BYTE* const dictEnd = info.dictContent + info.dictContentSize;
             for (j = 0; j < matchLen; j++) {
-                *srcPtr = *(srcPtr-offset);
+                if ((U32)((BYTE*)srcPtr - (BYTE*)frame->srcStart) < offset) {
+                    /* copy from dictionary instead of literals */
+                    size_t const dictOffset = offset - (srcPtr - (BYTE*)frame->srcStart);
+                    *srcPtr = *(dictEnd - dictOffset);
+                }
+                else {
+                    *srcPtr = *(srcPtr-offset);
+                }
                 srcPtr++;
             }
         }
@@ -931,7 +975,7 @@ static size_t writeSequences(U32* seed, frame_t* frame, seqStore_t* seqStorePtr,
 }
 
 static size_t writeSequencesBlock(U32* seed, frame_t* frame, size_t contentSize,
-                                  size_t literalsSize)
+                                  size_t literalsSize, dictInfo info)
 {
     seqStore_t seqStore;
     size_t numSequences;
@@ -940,14 +984,14 @@ static size_t writeSequencesBlock(U32* seed, frame_t* frame, size_t contentSize,
     initSeqStore(&seqStore);
 
     /* randomly generate sequences */
-    numSequences = generateSequences(seed, frame, &seqStore, contentSize, literalsSize);
+    numSequences = generateSequences(seed, frame, &seqStore, contentSize, literalsSize, info);
     /* write them out to the frame data */
     CHECKERR(writeSequences(seed, frame, &seqStore, numSequences));
 
     return numSequences;
 }
 
-static size_t writeCompressedBlock(U32* seed, frame_t* frame, size_t contentSize)
+static size_t writeCompressedBlock(U32* seed, frame_t* frame, size_t contentSize, dictInfo info)
 {
     BYTE* const blockStart = (BYTE*)frame->data;
     size_t literalsSize;
@@ -959,7 +1003,7 @@ static size_t writeCompressedBlock(U32* seed, frame_t* frame, size_t contentSize
 
     DISPLAYLEVEL(4, "   literals size: %u\n", (U32)literalsSize);
 
-    nbSeq = writeSequencesBlock(seed, frame, contentSize, literalsSize);
+    nbSeq = writeSequencesBlock(seed, frame, contentSize, literalsSize, info);
 
     DISPLAYLEVEL(4, "   number of sequences: %u\n", (U32)nbSeq);
 
@@ -967,7 +1011,7 @@ static size_t writeCompressedBlock(U32* seed, frame_t* frame, size_t contentSize
 }
 
 static void writeBlock(U32* seed, frame_t* frame, size_t contentSize,
-                       int lastBlock)
+                       int lastBlock, dictInfo info)
 {
     int const blockTypeDesc = RAND(seed) % 8;
     size_t blockSize;
@@ -1007,7 +1051,7 @@ static void writeBlock(U32* seed, frame_t* frame, size_t contentSize,
         frame->oldStats = frame->stats;
 
         frame->data = op;
-        compressedSize = writeCompressedBlock(seed, frame, contentSize);
+        compressedSize = writeCompressedBlock(seed, frame, contentSize, info);
         if (compressedSize > contentSize) {
             blockType = 0;
             memcpy(op, frame->src, contentSize);
@@ -1033,7 +1077,7 @@ static void writeBlock(U32* seed, frame_t* frame, size_t contentSize,
     frame->data = op;
 }
 
-static void writeBlocks(U32* seed, frame_t* frame)
+static void writeBlocks(U32* seed, frame_t* frame, dictInfo info)
 {
     size_t contentLeft = frame->header.contentSize;
     size_t const maxBlockSize = MIN(MAX_BLOCK_SIZE, frame->header.windowSize);
@@ -1056,7 +1100,7 @@ static void writeBlocks(U32* seed, frame_t* frame)
             }
         }
 
-        writeBlock(seed, frame, blockContentSize, lastBlock);
+        writeBlock(seed, frame, blockContentSize, lastBlock, info);
 
         contentLeft -= blockContentSize;
         if (lastBlock) break;
@@ -1121,20 +1165,102 @@ static void initFrame(frame_t* fr)
 }
 
 /* Return the final seed */
-static U32 generateFrame(U32 seed, frame_t* fr)
+static U32 generateFrame(U32 seed, frame_t* fr, dictInfo info)
 {
     /* generate a complete frame */
     DISPLAYLEVEL(1, "frame seed: %u\n", seed);
-
     initFrame(fr);
 
-    writeFrameHeader(&seed, fr);
-    writeBlocks(&seed, fr);
+    writeFrameHeader(&seed, fr, info);
+    writeBlocks(&seed, fr, info);
     writeChecksum(fr);
 
     return seed;
 }
 
+/*_*******************************************************
+*  Dictionary Helper Functions
+*********************************************************/
+/* returns 0 if successful, otherwise returns 1 upon error */
+static int genRandomDict(U32 dictID, U32 seed, size_t dictSize, BYTE* fullDict){
+    /* allocate space for samples */
+    int ret = 0;
+    unsigned const numSamples = 4;
+    size_t sampleSizes[4];
+    BYTE* const samples = malloc(5000*sizeof(BYTE));
+    if (samples == NULL) {
+        DISPLAY("Error: could not allocate space for samples\n");
+        return 1;
+    }
+
+    /* generate samples */
+    {
+        unsigned literalValue = 1;
+        unsigned samplesPos = 0;
+        size_t currSize = 1;
+        while (literalValue <= 4) {
+            sampleSizes[literalValue - 1] = currSize;
+            {
+                size_t k;
+                for (k = 0; k < currSize; k++) {
+                    *(samples + (samplesPos++)) = (BYTE)literalValue;
+                }
+            }
+            literalValue++;
+            currSize *= 16;
+        }
+    }
+
+
+    {
+        /* create variables */
+        size_t dictWriteSize = 0;
+        ZDICT_params_t zdictParams;
+        size_t const headerSize = MAX(dictSize/4, 256);
+        size_t const dictContentSize = dictSize - headerSize;
+        BYTE* const dictContent = fullDict + headerSize;
+        if (dictContentSize < ZDICT_CONTENTSIZE_MIN || dictSize < ZDICT_DICTSIZE_MIN) {
+            DISPLAY("Error: dictionary size is too small\n");
+            ret = 1;
+            goto exitGenRandomDict;
+        }
+
+        /* init dictionary params */
+        memset(&zdictParams, 0, sizeof(zdictParams));
+        zdictParams.dictID = dictID;
+        zdictParams.notificationLevel = 1;
+
+        /* fill in dictionary content */
+        RAND_buffer(&seed, (void*)dictContent, dictContentSize);
+
+        /* finalize dictionary with random samples */
+        dictWriteSize = ZDICT_finalizeDictionary(fullDict, dictSize,
+                                    dictContent, dictContentSize,
+                                    samples, sampleSizes, numSamples,
+                                    zdictParams);
+
+        if (ZDICT_isError(dictWriteSize)) {
+            DISPLAY("Could not finalize dictionary: %s\n", ZDICT_getErrorName(dictWriteSize));
+            ret = 1;
+        }
+    }
+
+exitGenRandomDict:
+    free(samples);
+    return ret;
+}
+
+static dictInfo initDictInfo(int useDict, size_t dictContentSize, BYTE* dictContent, U32 dictID){
+    /* allocate space statically */
+    dictInfo dictOp;
+    memset(&dictOp, 0, sizeof(dictOp));
+    dictOp.useDict = useDict;
+    dictOp.dictContentSize = dictContentSize;
+    dictOp.dictContent = dictContent;
+    dictOp.dictID = dictID;
+    return dictOp;
+}
+
 /*-*******************************************************
 *  Test Mode
 *********************************************************/
@@ -1196,6 +1322,65 @@ cleanup:
     return ret;
 }
 
+static size_t testDecodeWithDict(U32 seed)
+{
+    /* create variables */
+    size_t const dictSize = RAND(&seed) % (10 << 20) + ZDICT_DICTSIZE_MIN + ZDICT_CONTENTSIZE_MIN;
+    U32 const dictID = RAND(&seed);
+    size_t errorDetected = 0;
+    BYTE* const fullDict = malloc(dictSize);
+    if (fullDict == NULL) {
+        return ERROR(GENERIC);
+    }
+
+    /* generate random dictionary */
+    {
+        int const ret = genRandomDict(dictID, seed, dictSize, fullDict);
+        if (ret != 0) {
+            errorDetected = ERROR(GENERIC);
+            goto dictTestCleanup;
+        }
+    }
+
+
+    {
+        frame_t fr;
+
+        /* generate frame */
+        {
+            size_t const headerSize = MAX(dictSize/4, 256);
+            size_t const dictContentSize = dictSize-headerSize;
+            BYTE* const dictContent = fullDict+headerSize;
+            dictInfo const info = initDictInfo(1, dictContentSize, dictContent, dictID);
+            seed = generateFrame(seed, &fr, info);
+        }
+
+        /* manually decompress and check difference */
+        {
+            ZSTD_DCtx* const dctx = ZSTD_createDCtx();
+            {
+                size_t const returnValue = ZSTD_decompress_usingDict(dctx, DECOMPRESSED_BUFFER, MAX_DECOMPRESSED_SIZE,
+                                                       fr.dataStart, (BYTE*)fr.data - (BYTE*)fr.dataStart,
+                                                       fullDict, dictSize);
+                if (ZSTD_isError(returnValue)) {
+                    errorDetected = returnValue;
+                    goto dictTestCleanup;
+                }
+            }
+
+            if (memcmp(DECOMPRESSED_BUFFER, fr.srcStart, (BYTE*)fr.src - (BYTE*)fr.srcStart) != 0) {
+                errorDetected = ERROR(corruption_detected);
+                goto dictTestCleanup;
+            }
+            ZSTD_freeDCtx(dctx);
+        }
+    }
+
+dictTestCleanup:
+    free(fullDict);
+    return errorDetected;
+}
+
 static int runTestMode(U32 seed, unsigned numFiles, unsigned const testDurationS)
 {
     unsigned fnum;
@@ -1209,28 +1394,39 @@ static int runTestMode(U32 seed, unsigned numFiles, unsigned const testDurationS
 
     for (fnum = 0; fnum < numFiles || clockSpan(startClock) < maxClockSpan; fnum++) {
         frame_t fr;
-
+        U32 const seedCopy = seed;
         if (fnum < numFiles)
             DISPLAYUPDATE("\r%u/%u        ", fnum, numFiles);
         else
             DISPLAYUPDATE("\r%u           ", fnum);
 
-        seed = generateFrame(seed, &fr);
+        {
+            dictInfo const info = initDictInfo(0, 0, NULL, 0);
+            seed = generateFrame(seed, &fr, info);
+        }
 
         {   size_t const r = testDecodeSimple(&fr);
             if (ZSTD_isError(r)) {
-                DISPLAY("Error in simple mode on test seed %u: %s\n", seed + fnum,
+                DISPLAY("Error in simple mode on test seed %u: %s\n", seedCopy,
                         ZSTD_getErrorName(r));
                 return 1;
             }
         }
         {   size_t const r = testDecodeStreaming(&fr);
             if (ZSTD_isError(r)) {
-                DISPLAY("Error in streaming mode on test seed %u: %s\n", seed + fnum,
+                DISPLAY("Error in streaming mode on test seed %u: %s\n", seedCopy,
                         ZSTD_getErrorName(r));
                 return 1;
             }
         }
+        {
+            /* don't create a dictionary that is too big */
+            size_t const r = testDecodeWithDict(seed);
+            if (ZSTD_isError(r)) {
+                DISPLAY("Error in dictionary mode on test seed %u: %s\n", seedCopy, ZSTD_getErrorName(r));
+                return 1;
+            }
+        }
     }
 
     DISPLAY("\r%u tests completed: ", fnum);
@@ -1250,7 +1446,10 @@ static int generateFile(U32 seed, const char* const path,
 
     DISPLAY("seed: %u\n", seed);
 
-    generateFrame(seed, &fr);
+    {
+        dictInfo const info = initDictInfo(0, 0, NULL, 0);
+        generateFrame(seed, &fr, info);
+    }
 
     outputBuffer(fr.dataStart, (BYTE*)fr.data - (BYTE*)fr.dataStart, path);
     if (origPath) {
@@ -1272,7 +1471,10 @@ static int generateCorpus(U32 seed, unsigned numFiles, const char* const path,
 
         DISPLAYUPDATE("\r%u/%u        ", fnum, numFiles);
 
-        seed = generateFrame(seed, &fr);
+        {
+            dictInfo const info = initDictInfo(0, 0, NULL, 0);
+            seed = generateFrame(seed, &fr, info);
+        }
 
         if (snprintf(outPath, MAX_PATH, "%s/z%06u.zst", path, fnum) + 1 > MAX_PATH) {
             DISPLAY("Error: path too long\n");
@@ -1294,6 +1496,93 @@ static int generateCorpus(U32 seed, unsigned numFiles, const char* const path,
     return 0;
 }
 
+static int generateCorpusWithDict(U32 seed, unsigned numFiles, const char* const path,
+                                    const char* const origPath, const size_t dictSize)
+{
+    char outPath[MAX_PATH];
+    BYTE* fullDict;
+    U32 const dictID = RAND(&seed);
+    int errorDetected = 0;
+
+    if (snprintf(outPath, MAX_PATH, "%s/dictionary", path) + 1 > MAX_PATH) {
+        DISPLAY("Error: path too long\n");
+        return 1;
+    }
+
+    /* allocate space for the dictionary */
+    fullDict = malloc(dictSize);
+    if (fullDict == NULL) {
+        DISPLAY("Error: could not allocate space for full dictionary.\n");
+        return 1;
+    }
+
+    /* randomly generate the dictionary */
+    {
+        int const ret = genRandomDict(dictID, seed, dictSize, fullDict);
+        if (ret != 0) {
+            errorDetected = ret;
+            goto dictCleanup;
+        }
+    }
+
+    /* write out dictionary */
+    if (numFiles != 0) {
+        if (snprintf(outPath, MAX_PATH, "%s/dictionary", path) + 1 > MAX_PATH) {
+            DISPLAY("Error: dictionary path too long\n");
+            errorDetected = 1;
+            goto dictCleanup;
+        }
+        outputBuffer(fullDict, dictSize, outPath);
+    }
+    else {
+        outputBuffer(fullDict, dictSize, "dictionary");
+    }
+
+    /* generate random compressed/decompressed files */
+    {
+        unsigned fnum;
+        for (fnum = 0; fnum < MAX(numFiles, 1); fnum++) {
+            frame_t fr;
+            DISPLAYUPDATE("\r%u/%u        ", fnum, numFiles);
+            {
+                size_t const headerSize = MAX(dictSize/4, 256);
+                size_t const dictContentSize = dictSize-headerSize;
+                BYTE* const dictContent = fullDict+headerSize;
+                dictInfo const info = initDictInfo(1, dictContentSize, dictContent, dictID);
+                seed = generateFrame(seed, &fr, info);
+            }
+
+            if (numFiles != 0) {
+                if (snprintf(outPath, MAX_PATH, "%s/z%06u.zst", path, fnum) + 1 > MAX_PATH) {
+                    DISPLAY("Error: path too long\n");
+                    errorDetected = 1;
+                    goto dictCleanup;
+                }
+                outputBuffer(fr.dataStart, (BYTE*)fr.data - (BYTE*)fr.dataStart, outPath);
+
+                if (origPath) {
+                    if (snprintf(outPath, MAX_PATH, "%s/z%06u", origPath, fnum) + 1 > MAX_PATH) {
+                        DISPLAY("Error: path too long\n");
+                        errorDetected = 1;
+                        goto dictCleanup;
+                    }
+                    outputBuffer(fr.srcStart, (BYTE*)fr.src - (BYTE*)fr.srcStart, outPath);
+                }
+            }
+            else {
+                outputBuffer(fr.dataStart, (BYTE*)fr.data - (BYTE*)fr.dataStart, path);
+                if (origPath) {
+                    outputBuffer(fr.srcStart, (BYTE*)fr.src - (BYTE*)fr.srcStart, origPath);
+                }
+            }
+        }
+    }
+
+dictCleanup:
+    free(fullDict);
+    return errorDetected;
+}
+
 
 /*_*******************************************************
 *  Command line
@@ -1339,6 +1628,40 @@ static void advancedUsage(const char* programName)
     DISPLAY( "\n");
     DISPLAY( "Advanced arguments :\n");
     DISPLAY( " --content-size    : always include the content size in the frame header\n");
+    DISPLAY( " --use-dict=#      : include a dictionary used to decompress the corpus\n");
+}
+
+/*! readU32FromChar() :
+    @return : unsigned integer value read from input in `char` format
+    allows and interprets K, KB, KiB, M, MB and MiB suffix.
+    Will also modify `*stringPtr`, advancing it to position where it stopped reading.
+    Note : function result can overflow if digit string > MAX_UINT */
+static unsigned readU32FromChar(const char** stringPtr)
+{
+    unsigned result = 0;
+    while ((**stringPtr >='0') && (**stringPtr <='9'))
+        result *= 10, result += **stringPtr - '0', (*stringPtr)++ ;
+    if ((**stringPtr=='K') || (**stringPtr=='M')) {
+        result <<= 10;
+        if (**stringPtr=='M') result <<= 10;
+        (*stringPtr)++ ;
+        if (**stringPtr=='i') (*stringPtr)++;
+        if (**stringPtr=='B') (*stringPtr)++;
+    }
+    return result;
+}
+
+/** longCommandWArg() :
+ *  check if *stringPtr is the same as longCommand.
+ *  If yes, @return 1 and advances *stringPtr to the position which immediately follows longCommand.
+ *  @return 0 and doesn't modify *stringPtr otherwise.
+ */
+static unsigned longCommandWArg(const char** stringPtr, const char* longCommand)
+{
+    size_t const comSize = strlen(longCommand);
+    int const result = !strncmp(*stringPtr, longCommand, comSize);
+    if (result) *stringPtr += comSize;
+    return result;
 }
 
 int main(int argc, char** argv)
@@ -1350,6 +1673,8 @@ int main(int argc, char** argv)
     int testMode = 0;
     const char* path = NULL;
     const char* origPath = NULL;
+    int useDict = 0;
+    unsigned dictSize = (10 << 10); /* 10 kB default */
 
     int argNb;
 
@@ -1410,6 +1735,9 @@ int main(int argc, char** argv)
                     argument++;
                     if (strcmp(argument, "content-size") == 0) {
                         opts.contentSize = 1;
+                    } else if (longCommandWArg(&argument, "use-dict=")) {
+                        dictSize = readU32FromChar(&argument);
+                        useDict = 1;
                     } else {
                         advancedUsage(argv[0]);
                         return 1;
@@ -1441,9 +1769,13 @@ int main(int argc, char** argv)
         return 1;
     }
 
-    if (numFiles == 0) {
+    if (numFiles == 0 && useDict == 0) {
         return generateFile(seed, path, origPath);
-    } else {
+    } else if (useDict == 0){
         return generateCorpus(seed, numFiles, path, origPath);
+    } else {
+        /* should generate files with a dictionary */
+        return generateCorpusWithDict(seed, numFiles, path, origPath, dictSize);
     }
+
 }
diff --git a/tests/fullbench.c b/tests/fullbench.c
index 38cf22fa7ebc..81de5157b8e1 100644
--- a/tests/fullbench.c
+++ b/tests/fullbench.c
@@ -14,19 +14,19 @@
 #include "util.h"        /* Compiler options, UTIL_GetFileSize */
 #include <stdlib.h>      /* malloc */
 #include <stdio.h>       /* fprintf, fopen, ftello64 */
-#include <time.h>        /* clock_t, clock, CLOCKS_PER_SEC */
 
-#include "mem.h"
+#include "mem.h"         /* U32 */
 #ifndef ZSTD_DLL_IMPORT
     #include "zstd_internal.h"   /* ZSTD_blockHeaderSize, blockType_e, KB, MB */
-    #define ZSTD_STATIC_LINKING_ONLY  /* ZSTD_compressBegin, ZSTD_compressContinue, etc. */
 #else
     #define KB *(1 <<10)
     #define MB *(1 <<20)
     #define GB *(1U<<30)
     typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e;
 #endif
-#include "zstd.h"            /* ZSTD_VERSION_STRING */
+#define ZSTD_STATIC_LINKING_ONLY  /* ZSTD_compressBegin, ZSTD_compressContinue, etc. */
+#include "zstd.h"        /* ZSTD_versionString */
+#include "util.h"        /* time functions */
 #include "datagen.h"
 
 
@@ -35,7 +35,7 @@
 **************************************/
 #define PROGRAM_DESCRIPTION "Zstandard speed analyzer"
 #define AUTHOR "Yann Collet"
-#define WELCOME_MESSAGE "*** %s %s %i-bits, by %s (%s) ***\n", PROGRAM_DESCRIPTION, ZSTD_VERSION_STRING, (int)(sizeof(void*)*8), AUTHOR, __DATE__
+#define WELCOME_MESSAGE "*** %s %s %i-bits, by %s (%s) ***\n", PROGRAM_DESCRIPTION, ZSTD_versionString(), (int)(sizeof(void*)*8), AUTHOR, __DATE__
 
 #define NBLOOPS    6
 #define TIMELOOP_S 2
@@ -69,12 +69,6 @@ static void BMK_SetNbIterations(U32 nbLoops)
 /*_*******************************************************
 *  Private functions
 *********************************************************/
-static clock_t BMK_clockSpan( clock_t clockStart )
-{
-    return clock() - clockStart;   /* works even if overflow, span limited to <= ~30mn */
-}
-
-
 static size_t BMK_findMaxMem(U64 requiredMem)
 {
     size_t const step = 64 MB;
@@ -116,8 +110,9 @@ size_t local_ZSTD_decompress(void* dst, size_t dstSize, void* buff2, const void*
     return ZSTD_decompress(dst, dstSize, buff2, g_cSize);
 }
 
-#ifndef ZSTD_DLL_IMPORT
 static ZSTD_DCtx* g_zdc = NULL;
+
+#ifndef ZSTD_DLL_IMPORT
 extern size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* ctx, const void* src, size_t srcSize);
 size_t local_ZSTD_decodeLiteralsBlock(void* dst, size_t dstSize, void* buff2, const void* src, size_t srcSize)
 {
@@ -153,6 +148,74 @@ size_t local_ZSTD_compressStream(void* dst, size_t dstCapacity, void* buff2, con
     return buffOut.pos;
 }
 
+static size_t local_ZSTD_compress_generic_end(void* dst, size_t dstCapacity, void* buff2, const void* src, size_t srcSize)
+{
+    ZSTD_outBuffer buffOut;
+    ZSTD_inBuffer buffIn;
+    (void)buff2;
+    ZSTD_CCtx_setParameter(g_cstream, ZSTD_p_compressionLevel, 1);
+    buffOut.dst = dst;
+    buffOut.size = dstCapacity;
+    buffOut.pos = 0;
+    buffIn.src = src;
+    buffIn.size = srcSize;
+    buffIn.pos = 0;
+    ZSTD_compress_generic(g_cstream, &buffOut, &buffIn, ZSTD_e_end);
+    return buffOut.pos;
+}
+
+static size_t local_ZSTD_compress_generic_continue(void* dst, size_t dstCapacity, void* buff2, const void* src, size_t srcSize)
+{
+    ZSTD_outBuffer buffOut;
+    ZSTD_inBuffer buffIn;
+    (void)buff2;
+    ZSTD_CCtx_setParameter(g_cstream, ZSTD_p_compressionLevel, 1);
+    buffOut.dst = dst;
+    buffOut.size = dstCapacity;
+    buffOut.pos = 0;
+    buffIn.src = src;
+    buffIn.size = srcSize;
+    buffIn.pos = 0;
+    ZSTD_compress_generic(g_cstream, &buffOut, &buffIn, ZSTD_e_continue);
+    ZSTD_compress_generic(g_cstream, &buffOut, &buffIn, ZSTD_e_end);
+    return buffOut.pos;
+}
+
+static size_t local_ZSTD_compress_generic_T2_end(void* dst, size_t dstCapacity, void* buff2, const void* src, size_t srcSize)
+{
+    ZSTD_outBuffer buffOut;
+    ZSTD_inBuffer buffIn;
+    (void)buff2;
+    ZSTD_CCtx_setParameter(g_cstream, ZSTD_p_compressionLevel, 1);
+    ZSTD_CCtx_setParameter(g_cstream, ZSTD_p_nbThreads, 2);
+    buffOut.dst = dst;
+    buffOut.size = dstCapacity;
+    buffOut.pos = 0;
+    buffIn.src = src;
+    buffIn.size = srcSize;
+    buffIn.pos = 0;
+    while (ZSTD_compress_generic(g_cstream, &buffOut, &buffIn, ZSTD_e_end)) {}
+    return buffOut.pos;
+}
+
+static size_t local_ZSTD_compress_generic_T2_continue(void* dst, size_t dstCapacity, void* buff2, const void* src, size_t srcSize)
+{
+    ZSTD_outBuffer buffOut;
+    ZSTD_inBuffer buffIn;
+    (void)buff2;
+    ZSTD_CCtx_setParameter(g_cstream, ZSTD_p_compressionLevel, 1);
+    ZSTD_CCtx_setParameter(g_cstream, ZSTD_p_nbThreads, 2);
+    buffOut.dst = dst;
+    buffOut.size = dstCapacity;
+    buffOut.pos = 0;
+    buffIn.src = src;
+    buffIn.size = srcSize;
+    buffIn.pos = 0;
+    ZSTD_compress_generic(g_cstream, &buffOut, &buffIn, ZSTD_e_continue);
+    while(ZSTD_compress_generic(g_cstream, &buffOut, &buffIn, ZSTD_e_end)) {}
+    return buffOut.pos;
+}
+
 static ZSTD_DStream* g_dstream= NULL;
 static size_t local_ZSTD_decompressStream(void* dst, size_t dstCapacity, void* buff2, const void* src, size_t srcSize)
 {
@@ -170,8 +233,9 @@ static size_t local_ZSTD_decompressStream(void* dst, size_t dstCapacity, void* b
     return buffOut.pos;
 }
 
-#ifndef ZSTD_DLL_IMPORT
 static ZSTD_CCtx* g_zcc = NULL;
+
+#ifndef ZSTD_DLL_IMPORT
 size_t local_ZSTD_compressContinue(void* dst, size_t dstCapacity, void* buff2, const void* src, size_t srcSize)
 {
     (void)buff2;
@@ -236,33 +300,45 @@ static size_t benchMem(const void* src, size_t srcSize, U32 benchNb)
     switch(benchNb)
     {
     case 1:
-        benchFunction = local_ZSTD_compress; benchName = "ZSTD_compress";
+        benchFunction = local_ZSTD_compress; benchName = "compress(1)";
         break;
     case 2:
-        benchFunction = local_ZSTD_decompress; benchName = "ZSTD_decompress";
+        benchFunction = local_ZSTD_decompress; benchName = "decompress";
         break;
 #ifndef ZSTD_DLL_IMPORT
     case 11:
-        benchFunction = local_ZSTD_compressContinue; benchName = "ZSTD_compressContinue";
+        benchFunction = local_ZSTD_compressContinue; benchName = "compressContinue(1)";
         break;
     case 12:
-        benchFunction = local_ZSTD_compressContinue_extDict; benchName = "ZSTD_compressContinue_extDict";
+        benchFunction = local_ZSTD_compressContinue_extDict; benchName = "compressContinue_extDict";
         break;
     case 13:
-        benchFunction = local_ZSTD_decompressContinue; benchName = "ZSTD_decompressContinue";
+        benchFunction = local_ZSTD_decompressContinue; benchName = "decompressContinue";
         break;
     case 31:
-        benchFunction = local_ZSTD_decodeLiteralsBlock; benchName = "ZSTD_decodeLiteralsBlock";
+        benchFunction = local_ZSTD_decodeLiteralsBlock; benchName = "decodeLiteralsBlock";
         break;
     case 32:
-        benchFunction = local_ZSTD_decodeSeqHeaders; benchName = "ZSTD_decodeSeqHeaders";
+        benchFunction = local_ZSTD_decodeSeqHeaders; benchName = "decodeSeqHeaders";
         break;
 #endif
     case 41:
-        benchFunction = local_ZSTD_compressStream; benchName = "ZSTD_compressStream";
+        benchFunction = local_ZSTD_compressStream; benchName = "compressStream(1)";
         break;
     case 42:
-        benchFunction = local_ZSTD_decompressStream; benchName = "ZSTD_decompressStream";
+        benchFunction = local_ZSTD_decompressStream; benchName = "decompressStream";
+        break;
+    case 51:
+        benchFunction = local_ZSTD_compress_generic_continue; benchName = "compress_generic, continue";
+        break;
+    case 52:
+        benchFunction = local_ZSTD_compress_generic_end; benchName = "compress_generic, end";
+        break;
+    case 61:
+        benchFunction = local_ZSTD_compress_generic_T2_continue; benchName = "compress_generic, -T2, continue";
+        break;
+    case 62:
+        benchFunction = local_ZSTD_compress_generic_T2_end; benchName = "compress_generic, -T2, end";
         break;
     default :
         return 0;
@@ -276,6 +352,10 @@ static size_t benchMem(const void* src, size_t srcSize, U32 benchNb)
         free(dstBuff); free(buff2);
         return 12;
     }
+    if (g_zcc==NULL) g_zcc = ZSTD_createCCtx();
+    if (g_zdc==NULL) g_zdc = ZSTD_createDCtx();
+    if (g_cstream==NULL) g_cstream = ZSTD_createCStream();
+    if (g_dstream==NULL) g_dstream = ZSTD_createDStream();
 
     /* Preparation */
     switch(benchNb)
@@ -284,23 +364,15 @@ static size_t benchMem(const void* src, size_t srcSize, U32 benchNb)
         g_cSize = ZSTD_compress(buff2, dstBuffSize, src, srcSize, 1);
         break;
 #ifndef ZSTD_DLL_IMPORT
-    case 11 :
-        if (g_zcc==NULL) g_zcc = ZSTD_createCCtx();
-        break;
-    case 12 :
-        if (g_zcc==NULL) g_zcc = ZSTD_createCCtx();
-        break;
     case 13 :
-        if (g_zdc==NULL) g_zdc = ZSTD_createDCtx();
         g_cSize = ZSTD_compress(buff2, dstBuffSize, src, srcSize, 1);
         break;
     case 31:  /* ZSTD_decodeLiteralsBlock */
-        if (g_zdc==NULL) g_zdc = ZSTD_createDCtx();
         {   blockProperties_t bp;
-            ZSTD_frameParams zfp;
+            ZSTD_frameHeader zfp;
             size_t frameHeaderSize, skippedSize;
             g_cSize = ZSTD_compress(dstBuff, dstBuffSize, src, srcSize, 1);
-            frameHeaderSize = ZSTD_getFrameParams(&zfp, dstBuff, ZSTD_frameHeaderSize_min);
+            frameHeaderSize = ZSTD_getFrameHeader(&zfp, dstBuff, ZSTD_frameHeaderSize_min);
             if (frameHeaderSize==0) frameHeaderSize = ZSTD_frameHeaderSize_min;
             ZSTD_getcBlockSize(dstBuff+frameHeaderSize, dstBuffSize, &bp);  /* Get 1st block type */
             if (bp.blockType != bt_compressed) {
@@ -313,15 +385,14 @@ static size_t benchMem(const void* src, size_t srcSize, U32 benchNb)
             break;
         }
     case 32:   /* ZSTD_decodeSeqHeaders */
-        if (g_zdc==NULL) g_zdc = ZSTD_createDCtx();
         {   blockProperties_t bp;
-            ZSTD_frameParams zfp;
+            ZSTD_frameHeader zfp;
             const BYTE* ip = dstBuff;
             const BYTE* iend;
             size_t frameHeaderSize, cBlockSize;
             ZSTD_compress(dstBuff, dstBuffSize, src, srcSize, 1);   /* it would be better to use direct block compression here */
             g_cSize = ZSTD_compress(dstBuff, dstBuffSize, src, srcSize, 1);
-            frameHeaderSize = ZSTD_getFrameParams(&zfp, dstBuff, ZSTD_frameHeaderSize_min);
+            frameHeaderSize = ZSTD_getFrameHeader(&zfp, dstBuff, ZSTD_frameHeaderSize_min);
             if (frameHeaderSize==0) frameHeaderSize = ZSTD_frameHeaderSize_min;
             ip += frameHeaderSize;   /* Skip frame Header */
             cBlockSize = ZSTD_getcBlockSize(ip, dstBuffSize, &bp);   /* Get 1st block type */
@@ -342,11 +413,7 @@ static size_t benchMem(const void* src, size_t srcSize, U32 benchNb)
     case 31:
         goto _cleanOut;
 #endif
-    case 41 :
-        if (g_cstream==NULL) g_cstream = ZSTD_createCStream();
-        break;
     case 42 :
-        if (g_dstream==NULL) g_dstream = ZSTD_createDStream();
         g_cSize = ZSTD_compress(buff2, dstBuffSize, src, srcSize, 1);
         break;
 
@@ -359,30 +426,37 @@ static size_t benchMem(const void* src, size_t srcSize, U32 benchNb)
     { size_t i; for (i=0; i<dstBuffSize; i++) dstBuff[i]=(BYTE)i; }     /* warming up memory */
 
     {   U32 loopNb;
+#       define TIME_SEC_MICROSEC     (1*1000000ULL) /* 1 second */
+        U64 const clockLoop = TIMELOOP_S * TIME_SEC_MICROSEC;
+        UTIL_freq_t ticksPerSecond;
+        UTIL_initTimer(&ticksPerSecond);
         DISPLAY("%2i- %-30.30s : \r", benchNb, benchName);
         for (loopNb = 1; loopNb <= g_nbIterations; loopNb++) {
-            clock_t const timeLoop = TIMELOOP_S * CLOCKS_PER_SEC;
-            clock_t clockStart;
-            U32 nbRounds;
+            UTIL_time_t clockStart;
             size_t benchResult=0;
-            double averageTime;
+            U32 nbRounds;
 
-            clockStart = clock();
-            while (clock() == clockStart);
-            clockStart = clock();
-            for (nbRounds=0; BMK_clockSpan(clockStart) < timeLoop; nbRounds++) {
+            UTIL_sleepMilli(1);  /* give processor time to other processes */
+            UTIL_waitForNextTick(ticksPerSecond);
+            UTIL_getTime(&clockStart);
+            for (nbRounds=0; UTIL_clockSpanMicro(clockStart, ticksPerSecond) < clockLoop; nbRounds++) {
                 benchResult = benchFunction(dstBuff, dstBuffSize, buff2, src, srcSize);
                 if (ZSTD_isError(benchResult)) { DISPLAY("ERROR ! %s() => %s !! \n", benchName, ZSTD_getErrorName(benchResult)); exit(1); }
             }
-            averageTime = (((double)BMK_clockSpan(clockStart)) / CLOCKS_PER_SEC) / nbRounds;
-            if (averageTime < bestTime) bestTime = averageTime;
-            DISPLAY("%2i- %-30.30s : %7.1f MB/s  (%9u)\r", loopNb, benchName, (double)srcSize / (1 MB) / bestTime, (U32)benchResult);
-    }   }
+            {   U64 const clockSpanMicro = UTIL_clockSpanMicro(clockStart, ticksPerSecond);
+                double const averageTime = (double)clockSpanMicro / TIME_SEC_MICROSEC / nbRounds;
+                if (averageTime < bestTime) bestTime = averageTime;
+                DISPLAY("%2i- %-30.30s : %7.1f MB/s  (%9u)\r", loopNb, benchName, (double)srcSize / (1 MB) / bestTime, (U32)benchResult);
+    }   }   }
     DISPLAY("%2u\n", benchNb);
 
 _cleanOut:
     free(dstBuff);
     free(buff2);
+    ZSTD_freeCCtx(g_zcc); g_zcc=NULL;
+    ZSTD_freeDCtx(g_zdc); g_zdc=NULL;
+    ZSTD_freeCStream(g_cstream); g_cstream=NULL;
+    ZSTD_freeDStream(g_dstream); g_dstream=NULL;
     return 0;
 }
 
diff --git a/tests/fuzzer.c b/tests/fuzzer.c
index a9dcf12e0702..b8f514785542 100644
--- a/tests/fuzzer.c
+++ b/tests/fuzzer.c
@@ -12,9 +12,9 @@
 *  Compiler specific
 **************************************/
 #ifdef _MSC_VER    /* Visual Studio */
-#  define _CRT_SECURE_NO_WARNINGS     /* fgets */
-#  pragma warning(disable : 4127)     /* disable: C4127: conditional expression is constant */
-#  pragma warning(disable : 4204)     /* disable: C4204: non-constant aggregate initializer */
+#  define _CRT_SECURE_NO_WARNINGS   /* fgets */
+#  pragma warning(disable : 4127)   /* disable: C4127: conditional expression is constant */
+#  pragma warning(disable : 4204)   /* disable: C4204: non-constant aggregate initializer */
 #endif
 
 
@@ -25,7 +25,7 @@
 #include <stdio.h>        /* fgets, sscanf */
 #include <string.h>       /* strcmp */
 #include <time.h>         /* clock_t */
-#define ZSTD_STATIC_LINKING_ONLY   /* ZSTD_compressContinue, ZSTD_compressBlock */
+#define ZSTD_STATIC_LINKING_ONLY  /* ZSTD_compressContinue, ZSTD_compressBlock */
 #include "zstd.h"         /* ZSTD_VERSION_STRING */
 #include "zstd_errors.h"  /* ZSTD_getErrorCode */
 #include "zstdmt_compress.h"
@@ -74,7 +74,6 @@ static clock_t FUZ_clockSpan(clock_t cStart)
     return clock() - cStart;   /* works even when overflow; max span ~ 30mn */
 }
 
-
 #define FUZ_rotl32(x,r) ((x << r) | (x >> (32 - r)))
 static unsigned FUZ_rand(unsigned* src)
 {
@@ -104,6 +103,7 @@ static unsigned FUZ_highbit32(U32 v32)
 #define CHECK_V(var, fn)  size_t const var = fn; if (ZSTD_isError(var)) goto _output_error
 #define CHECK(fn)  { CHECK_V(err, fn); }
 #define CHECKPLUS(var, fn, more)  { CHECK_V(var, fn); more; }
+
 static int basicUnitTests(U32 seed, double compressibility)
 {
     size_t const CNBuffSize = 5 MB;
@@ -190,6 +190,89 @@ static int basicUnitTests(U32 seed, double compressibility)
     DISPLAYLEVEL(4, "OK \n");
 
 
+    /* Static CCtx tests */
+#define STATIC_CCTX_LEVEL 3
+    DISPLAYLEVEL(4, "test%3i : create static CCtx for level %u :", testNb++, STATIC_CCTX_LEVEL);
+    {   size_t const staticCCtxSize = ZSTD_estimateCStreamSize(STATIC_CCTX_LEVEL);
+        void* const staticCCtxBuffer = malloc(staticCCtxSize);
+        size_t const staticDCtxSize = ZSTD_estimateDCtxSize();
+        void* const staticDCtxBuffer = malloc(staticDCtxSize);
+        if (staticCCtxBuffer==NULL || staticDCtxBuffer==NULL) {
+            free(staticCCtxBuffer);
+            free(staticDCtxBuffer);
+            DISPLAY("Not enough memory, aborting\n");
+            testResult = 1;
+            goto _end;
+        }
+        {   ZSTD_CCtx* staticCCtx = ZSTD_initStaticCCtx(staticCCtxBuffer, staticCCtxSize);
+            ZSTD_DCtx* staticDCtx = ZSTD_initStaticDCtx(staticDCtxBuffer, staticDCtxSize);
+            if ((staticCCtx==NULL) || (staticDCtx==NULL)) goto _output_error;
+            DISPLAYLEVEL(4, "OK \n");
+
+            DISPLAYLEVEL(4, "test%3i : init CCtx for level %u : ", testNb++, STATIC_CCTX_LEVEL);
+            { size_t const r = ZSTD_compressBegin(staticCCtx, STATIC_CCTX_LEVEL);
+              if (ZSTD_isError(r)) goto _output_error; }
+            DISPLAYLEVEL(4, "OK \n");
+
+            DISPLAYLEVEL(4, "test%3i : simple compression test with static CCtx : ", testNb++);
+            CHECKPLUS(r, ZSTD_compressCCtx(staticCCtx,
+                            compressedBuffer, ZSTD_compressBound(CNBuffSize),
+                            CNBuffer, CNBuffSize, STATIC_CCTX_LEVEL),
+                      cSize=r );
+            DISPLAYLEVEL(4, "OK (%u bytes : %.2f%%)\n",
+                            (U32)cSize, (double)cSize/CNBuffSize*100);
+
+            DISPLAYLEVEL(4, "test%3i : simple decompression test with static DCtx : ", testNb++);
+            { size_t const r = ZSTD_decompressDCtx(staticDCtx,
+                                                decodedBuffer, CNBuffSize,
+                                                compressedBuffer, cSize);
+              if (r != CNBuffSize) goto _output_error; }
+            DISPLAYLEVEL(4, "OK \n");
+
+            DISPLAYLEVEL(4, "test%3i : check decompressed result : ", testNb++);
+            {   size_t u;
+                for (u=0; u<CNBuffSize; u++) {
+                    if (((BYTE*)decodedBuffer)[u] != ((BYTE*)CNBuffer)[u])
+                        goto _output_error;;
+            }   }
+            DISPLAYLEVEL(4, "OK \n");
+
+            DISPLAYLEVEL(4, "test%3i : init CCtx for too large level (must fail) : ", testNb++);
+            { size_t const r = ZSTD_compressBegin(staticCCtx, ZSTD_maxCLevel());
+              if (!ZSTD_isError(r)) goto _output_error; }
+            DISPLAYLEVEL(4, "OK \n");
+
+            DISPLAYLEVEL(4, "test%3i : init CCtx for small level %u (should work again) : ", testNb++, 1);
+            { size_t const r = ZSTD_compressBegin(staticCCtx, 1);
+              if (ZSTD_isError(r)) goto _output_error; }
+            DISPLAYLEVEL(4, "OK \n");
+
+            DISPLAYLEVEL(4, "test%3i : init CStream for small level %u : ", testNb++, 1);
+            { size_t const r = ZSTD_initCStream(staticCCtx, 1);
+              if (ZSTD_isError(r)) goto _output_error; }
+            DISPLAYLEVEL(4, "OK \n");
+
+            DISPLAYLEVEL(4, "test%3i : init CStream with dictionary (should fail) : ", testNb++);
+            { size_t const r = ZSTD_initCStream_usingDict(staticCCtx, CNBuffer, 64 KB, 1);
+              if (!ZSTD_isError(r)) goto _output_error; }
+            DISPLAYLEVEL(4, "OK \n");
+
+            DISPLAYLEVEL(4, "test%3i : init DStream (should fail) : ", testNb++);
+            { size_t const r = ZSTD_initDStream(staticDCtx);
+              if (ZSTD_isError(r)) goto _output_error; }
+            {   ZSTD_outBuffer output = { decodedBuffer, CNBuffSize, 0 };
+                ZSTD_inBuffer input = { compressedBuffer, ZSTD_FRAMEHEADERSIZE_MAX+1, 0 };
+                size_t const r = ZSTD_decompressStream(staticDCtx, &output, &input);
+                if (!ZSTD_isError(r)) goto _output_error;
+            }
+            DISPLAYLEVEL(4, "OK \n");
+        }
+        free(staticCCtxBuffer);
+        free(staticDCtxBuffer);
+    }
+
+
+
     /* ZSTDMT simple MT compression test */
     DISPLAYLEVEL(4, "test%3i : create ZSTDMT CCtx : ", testNb++);
     {   ZSTDMT_CCtx* mtctx = ZSTDMT_createCCtx(2);
@@ -321,13 +404,25 @@ static int basicUnitTests(U32 seed, double compressibility)
         DISPLAYLEVEL(4, "OK \n");
 
         DISPLAYLEVEL(4, "test%3i : decompress with DDict : ", testNb++);
-        {   ZSTD_DDict* const ddict = ZSTD_createDDict_byReference(CNBuffer, dictSize);
+        {   ZSTD_DDict* const ddict = ZSTD_createDDict(CNBuffer, dictSize);
             size_t const r = ZSTD_decompress_usingDDict(dctx, decodedBuffer, CNBuffSize, compressedBuffer, cSize, ddict);
             if (r != CNBuffSize - dictSize) goto _output_error;
             DISPLAYLEVEL(4, "OK (size of DDict : %u) \n", (U32)ZSTD_sizeof_DDict(ddict));
             ZSTD_freeDDict(ddict);
         }
 
+        DISPLAYLEVEL(4, "test%3i : decompress with static DDict : ", testNb++);
+        {   size_t const ddictBufferSize = ZSTD_estimateDDictSize(dictSize, 0);
+            void* ddictBuffer = malloc(ddictBufferSize);
+            if (ddictBuffer == NULL) goto _output_error;
+            {   ZSTD_DDict* const ddict = ZSTD_initStaticDDict(ddictBuffer, ddictBufferSize, CNBuffer, dictSize, 0);
+                size_t const r = ZSTD_decompress_usingDDict(dctx, decodedBuffer, CNBuffSize, compressedBuffer, cSize, ddict);
+                if (r != CNBuffSize - dictSize) goto _output_error;
+            }
+            free(ddictBuffer);
+            DISPLAYLEVEL(4, "OK (size of static DDict : %u) \n", (U32)ddictBufferSize);
+        }
+
         DISPLAYLEVEL(4, "test%3i : check content size on duplicated context : ", testNb++);
         {   size_t const testSize = CNBuffSize / 3;
             {   ZSTD_parameters p = ZSTD_getParams(2, testSize, dictSize);
@@ -339,8 +434,8 @@ static int basicUnitTests(U32 seed, double compressibility)
             CHECKPLUS(r, ZSTD_compressEnd(ctxDuplicated, compressedBuffer, ZSTD_compressBound(testSize),
                                           (const char*)CNBuffer + dictSize, testSize),
                       cSize = r);
-            {   ZSTD_frameParams fp;
-                if (ZSTD_getFrameParams(&fp, compressedBuffer, cSize)) goto _output_error;
+            {   ZSTD_frameHeader fp;
+                if (ZSTD_getFrameHeader(&fp, compressedBuffer, cSize)) goto _output_error;
                 if ((fp.frameContentSize != testSize) && (fp.frameContentSize != 0)) goto _output_error;
         }   }
         DISPLAYLEVEL(4, "OK \n");
@@ -404,10 +499,18 @@ static int basicUnitTests(U32 seed, double compressibility)
                   if (r != CNBuffSize) goto _output_error);
         DISPLAYLEVEL(4, "OK \n");
 
-        DISPLAYLEVEL(4, "test%3i : compress with preprocessed dictionary : ", testNb++);
+        DISPLAYLEVEL(4, "test%3i : estimate CDict size : ", testNb++);
         {   ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBuffSize, dictSize);
-            ZSTD_customMem customMem = { NULL, NULL, NULL };
-            ZSTD_CDict* cdict = ZSTD_createCDict_advanced(dictBuffer, dictSize, 1, cParams, customMem);
+            size_t const estimatedSize = ZSTD_estimateCDictSize_advanced(dictSize, cParams, 1 /*byReference*/);
+            DISPLAYLEVEL(4, "OK : %u \n", (U32)estimatedSize);
+        }
+
+        DISPLAYLEVEL(4, "test%3i : compress with CDict ", testNb++);
+        {   ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBuffSize, dictSize);
+            ZSTD_CDict* const cdict = ZSTD_createCDict_advanced(dictBuffer, dictSize,
+                                            1 /* byReference */, ZSTD_dm_auto,
+                                            cParams, ZSTD_defaultCMem);
+            DISPLAYLEVEL(4, "(size : %u) : ", (U32)ZSTD_sizeof_CDict(cdict));
             cSize = ZSTD_compress_usingCDict(cctx, compressedBuffer, ZSTD_compressBound(CNBuffSize),
                                                  CNBuffer, CNBuffSize, cdict);
             ZSTD_freeCDict(cdict);
@@ -429,11 +532,34 @@ static int basicUnitTests(U32 seed, double compressibility)
                   if (r != CNBuffSize) goto _output_error);
         DISPLAYLEVEL(4, "OK \n");
 
+        DISPLAYLEVEL(4, "test%3i : compress with static CDict : ", testNb++);
+        {   ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBuffSize, dictSize);
+            size_t const cdictSize = ZSTD_estimateCDictSize_advanced(dictSize, cParams, 0);
+            void* const cdictBuffer = malloc(cdictSize);
+            if (cdictBuffer==NULL) goto _output_error;
+            {   ZSTD_CDict* const cdict = ZSTD_initStaticCDict(cdictBuffer, cdictSize,
+                                            dictBuffer, dictSize,
+                                            0 /* by Reference */, ZSTD_dm_auto,
+                                            cParams);
+                if (cdict == NULL) {
+                    DISPLAY("ZSTD_initStaticCDict failed ");
+                    goto _output_error;
+                }
+                cSize = ZSTD_compress_usingCDict(cctx,
+                                compressedBuffer, ZSTD_compressBound(CNBuffSize),
+                                CNBuffer, CNBuffSize, cdict);
+                if (ZSTD_isError(cSize)) {
+                    DISPLAY("ZSTD_compress_usingCDict failed ");
+                    goto _output_error;
+            }   }
+            free(cdictBuffer);
+        }
+        DISPLAYLEVEL(4, "OK (%u bytes : %.2f%%)\n", (U32)cSize, (double)cSize/CNBuffSize*100);
+
         DISPLAYLEVEL(4, "test%3i : ZSTD_compress_usingCDict_advanced, no contentSize, no dictID : ", testNb++);
         {   ZSTD_frameParameters const fParams = { 0 /* frameSize */, 1 /* checksum */, 1 /* noDictID*/ };
             ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBuffSize, dictSize);
-            ZSTD_customMem const customMem = { NULL, NULL, NULL };
-            ZSTD_CDict* const cdict = ZSTD_createCDict_advanced(dictBuffer, dictSize, 1, cParams, customMem);
+            ZSTD_CDict* const cdict = ZSTD_createCDict_advanced(dictBuffer, dictSize, 1 /*byRef*/, ZSTD_dm_auto, cParams, ZSTD_defaultCMem);
             cSize = ZSTD_compress_usingCDict_advanced(cctx, compressedBuffer, ZSTD_compressBound(CNBuffSize),
                                                  CNBuffer, CNBuffSize, cdict, fParams);
             ZSTD_freeCDict(cdict);
@@ -482,6 +608,22 @@ static int basicUnitTests(U32 seed, double compressibility)
         }
         DISPLAYLEVEL(4, "OK \n");
 
+        DISPLAYLEVEL(4, "test%3i : Building cdict w/ ZSTD_dm_fullDict on a good dictionary : ", testNb++);
+        {   ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBuffSize, dictSize);
+            ZSTD_CDict* const cdict = ZSTD_createCDict_advanced(dictBuffer, dictSize, 1 /*byRef*/, ZSTD_dm_fullDict, cParams, ZSTD_defaultCMem);
+            if (cdict==NULL) goto _output_error;
+            ZSTD_freeCDict(cdict);
+        }
+        DISPLAYLEVEL(4, "OK \n");
+
+        DISPLAYLEVEL(4, "test%3i : Building cdict w/ ZSTD_dm_fullDict on a rawContent (must fail) : ", testNb++);
+        {   ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBuffSize, dictSize);
+            ZSTD_CDict* const cdict = ZSTD_createCDict_advanced((const char*)dictBuffer+1, dictSize-1, 1 /*byRef*/, ZSTD_dm_fullDict, cParams, ZSTD_defaultCMem);
+            if (cdict!=NULL) goto _output_error;
+            ZSTD_freeCDict(cdict);
+        }
+        DISPLAYLEVEL(4, "OK \n");
+
         ZSTD_freeCCtx(cctx);
         free(dictBuffer);
         free(samplesSizes);
@@ -496,7 +638,7 @@ static int basicUnitTests(U32 seed, double compressibility)
         size_t const sampleUnitSize = 8 KB;
         U32 const nbSamples = (U32)(totalSampleSize / sampleUnitSize);
         size_t* const samplesSizes = (size_t*) malloc(nbSamples * sizeof(size_t));
-        COVER_params_t params;
+        ZDICT_cover_params_t params;
         U32 dictID;
 
         if (dictBuffer==NULL || samplesSizes==NULL) {
@@ -505,14 +647,14 @@ static int basicUnitTests(U32 seed, double compressibility)
             goto _output_error;
         }
 
-        DISPLAYLEVEL(4, "test%3i : COVER_trainFromBuffer : ", testNb++);
+        DISPLAYLEVEL(4, "test%3i : ZDICT_trainFromBuffer_cover : ", testNb++);
         { U32 u; for (u=0; u<nbSamples; u++) samplesSizes[u] = sampleUnitSize; }
         memset(&params, 0, sizeof(params));
         params.d = 1 + (FUZ_rand(&seed) % 16);
         params.k = params.d + (FUZ_rand(&seed) % 256);
-        dictSize = COVER_trainFromBuffer(dictBuffer, dictSize,
-                                         CNBuffer, samplesSizes, nbSamples,
-                                         params);
+        dictSize = ZDICT_trainFromBuffer_cover(dictBuffer, dictSize,
+                                               CNBuffer, samplesSizes, nbSamples,
+                                               params);
         if (ZDICT_isError(dictSize)) goto _output_error;
         DISPLAYLEVEL(4, "OK, created dictionary of size %u \n", (U32)dictSize);
 
@@ -521,12 +663,12 @@ static int basicUnitTests(U32 seed, double compressibility)
         if (dictID==0) goto _output_error;
         DISPLAYLEVEL(4, "OK : %u \n", dictID);
 
-        DISPLAYLEVEL(4, "test%3i : COVER_optimizeTrainFromBuffer : ", testNb++);
+        DISPLAYLEVEL(4, "test%3i : ZDICT_optimizeTrainFromBuffer_cover : ", testNb++);
         memset(&params, 0, sizeof(params));
         params.steps = 4;
-        optDictSize = COVER_optimizeTrainFromBuffer(dictBuffer, optDictSize,
-                                                    CNBuffer, samplesSizes, nbSamples / 4,
-                                                    &params);
+        optDictSize = ZDICT_optimizeTrainFromBuffer_cover(dictBuffer, optDictSize,
+                                                          CNBuffer, samplesSizes,
+                                                          nbSamples / 4, &params);
         if (ZDICT_isError(optDictSize)) goto _output_error;
         DISPLAYLEVEL(4, "OK, created dictionary of size %u \n", (U32)optDictSize);
 
@@ -560,9 +702,7 @@ static int basicUnitTests(U32 seed, double compressibility)
         size_t const wrongSrcSize = (srcSize + 1000);
         ZSTD_parameters params = ZSTD_getParams(1, wrongSrcSize, 0);
         params.fParams.contentSizeFlag = 1;
-        {   size_t const result = ZSTD_compressBegin_advanced(cctx, NULL, 0, params, wrongSrcSize);
-            if (ZSTD_isError(result)) goto _output_error;
-        }
+        CHECK( ZSTD_compressBegin_advanced(cctx, NULL, 0, params, wrongSrcSize) );
         {   size_t const result = ZSTD_compressEnd(cctx, decodedBuffer, CNBuffSize, CNBuffer, srcSize);
             if (!ZSTD_isError(result)) goto _output_error;
             if (ZSTD_getErrorCode(result) != ZSTD_error_srcSize_wrong) goto _output_error;
@@ -580,6 +720,7 @@ static int basicUnitTests(U32 seed, double compressibility)
         /* basic block compression */
         DISPLAYLEVEL(4, "test%3i : Block compression test : ", testNb++);
         CHECK( ZSTD_compressBegin(cctx, 5) );
+        CHECK( ZSTD_getBlockSize(cctx) >= blockSize);
         cSize = ZSTD_compressBlock(cctx, compressedBuffer, ZSTD_compressBound(blockSize), CNBuffer, blockSize);
         if (ZSTD_isError(cSize)) goto _output_error;
         DISPLAYLEVEL(4, "OK \n");
@@ -743,8 +884,23 @@ static size_t FUZ_randomLength(U32* seed, U32 maxLog)
 }
 
 #undef CHECK
-#define CHECK(cond, ...) if (cond) { DISPLAY("Error => "); DISPLAY(__VA_ARGS__); \
-                         DISPLAY(" (seed %u, test nb %u)  \n", seed, testNb); goto _output_error; }
+#define CHECK(cond, ...) {                                    \
+    if (cond) {                                               \
+        DISPLAY("Error => ");                                 \
+        DISPLAY(__VA_ARGS__);                                 \
+        DISPLAY(" (seed %u, test nb %u)  \n", seed, testNb);  \
+        goto _output_error;                                   \
+}   }
+
+#define CHECK_Z(f) {                                          \
+    size_t const err = f;                                     \
+    if (ZSTD_isError(err)) {                                  \
+        DISPLAY("Error => %s : %s ",                          \
+                #f, ZSTD_getErrorName(err));                  \
+        DISPLAY(" (seed %u, test nb %u)  \n", seed, testNb);  \
+        goto _output_error;                                   \
+}   }
+
 
 static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, U32 const maxDurationS, double compressibility, int bigTests)
 {
@@ -856,9 +1012,8 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, U32 const maxD
         }
 
         /* frame header decompression test */
-        {   ZSTD_frameParams dParams;
-            size_t const check = ZSTD_getFrameParams(&dParams, cBuffer, cSize);
-            CHECK(ZSTD_isError(check), "Frame Parameters extraction failed");
+        {   ZSTD_frameHeader dParams;
+            CHECK_Z( ZSTD_getFrameHeader(&dParams, cBuffer, cSize) );
             CHECK(dParams.frameContentSize != sampleSize, "Frame content size incorrect");
         }
 
@@ -945,20 +1100,17 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, U32 const maxD
             dict = srcBuffer + (FUZ_rand(&lseed) % (srcBufferSize - dictSize));
 
             if (FUZ_rand(&lseed) & 0xF) {
-                size_t const errorCode = ZSTD_compressBegin_usingDict(refCtx, dict, dictSize, cLevel);
-                CHECK (ZSTD_isError(errorCode), "ZSTD_compressBegin_usingDict error : %s", ZSTD_getErrorName(errorCode));
+                CHECK_Z ( ZSTD_compressBegin_usingDict(refCtx, dict, dictSize, cLevel) );
             } else {
                 ZSTD_compressionParameters const cPar = ZSTD_getCParams(cLevel, 0, dictSize);
                 ZSTD_frameParameters const fPar = { FUZ_rand(&lseed)&1 /* contentSizeFlag */,
                                                     !(FUZ_rand(&lseed)&3) /* contentChecksumFlag*/,
                                                     0 /*NodictID*/ };   /* note : since dictionary is fake, dictIDflag has no impact */
                 ZSTD_parameters const p = FUZ_makeParams(cPar, fPar);
-                size_t const errorCode = ZSTD_compressBegin_advanced(refCtx, dict, dictSize, p, 0);
-                CHECK (ZSTD_isError(errorCode), "ZSTD_compressBegin_advanced error : %s", ZSTD_getErrorName(errorCode));
+                CHECK_Z ( ZSTD_compressBegin_advanced(refCtx, dict, dictSize, p, 0) );
             }
-            {   size_t const errorCode = ZSTD_copyCCtx(ctx, refCtx, 0);
-                CHECK (ZSTD_isError(errorCode), "ZSTD_copyCCtx error : %s", ZSTD_getErrorName(errorCode));
-        }   }
+            CHECK_Z( ZSTD_copyCCtx(ctx, refCtx, 0) );
+        }
         ZSTD_setCCtxParameter(ctx, ZSTD_p_forceWindow, FUZ_rand(&lseed) & 1);
 
         {   U32 const nbChunks = (FUZ_rand(&lseed) & 127) + 2;
@@ -990,8 +1142,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, U32 const maxD
 
         /* streaming decompression test */
         if (dictSize<8) dictSize=0, dict=NULL;   /* disable dictionary */
-        { size_t const errorCode = ZSTD_decompressBegin_usingDict(dctx, dict, dictSize);
-          CHECK (ZSTD_isError(errorCode), "ZSTD_decompressBegin_usingDict error : %s", ZSTD_getErrorName(errorCode)); }
+        CHECK_Z( ZSTD_decompressBegin_usingDict(dctx, dict, dictSize) );
         totalCSize = 0;
         totalGenSize = 0;
         while (totalCSize < cSize) {
diff --git a/tests/paramgrill.c b/tests/paramgrill.c
index 1913b54d0a54..da06ccb52aab 100644
--- a/tests/paramgrill.c
+++ b/tests/paramgrill.c
@@ -38,7 +38,7 @@
 #define GB *(1ULL<<30)
 
 #define NBLOOPS    2
-#define TIMELOOP   (2 * CLOCKS_PER_SEC)
+#define TIMELOOP  (2 * CLOCKS_PER_SEC)
 
 #define NB_LEVELS_TRACKED 30
 
@@ -47,7 +47,7 @@ static const size_t maxMemory = (sizeof(size_t)==4)  ?  (2 GB - 64 MB) : (size_t
 #define COMPRESSIBILITY_DEFAULT 0.50
 static const size_t sampleSize = 10000000;
 
-static const U32 g_grillDuration_s = 60000;   /* about 16 hours */
+static const double g_grillDuration_s = 90000;   /* about 24 hours */
 static const clock_t g_maxParamTime = 15 * CLOCKS_PER_SEC;
 static const clock_t g_maxVariationTime = 60 * CLOCKS_PER_SEC;
 static const int g_maxNbVariations = 64;
@@ -87,9 +87,11 @@ void BMK_SetNbIterations(int nbLoops)
 *  Private functions
 *********************************************************/
 
-static clock_t BMK_clockSpan(clock_t cStart) { return clock() - cStart; }  /* works even if overflow ; max span ~ 30 mn */
+/* works even if overflow ; max span ~ 30 mn */
+static clock_t BMK_clockSpan(clock_t cStart) { return clock() - cStart; }
 
-static U32 BMK_timeSpan(time_t tStart) { return (U32)difftime(time(NULL), tStart); }  /* accuracy in seconds only, span can be multiple years */
+/* accuracy in seconds only, span can be multiple years */
+static double BMK_timeSpan(time_t tStart) { return difftime(time(NULL), tStart); }
 
 
 static size_t BMK_findMaxMem(U64 requiredMem)
@@ -307,14 +309,14 @@ static size_t BMK_benchParam(BMK_result_t* resultPtr,
 }
 
 
-const char* g_stratName[] = { "ZSTD_fast   ",
-                              "ZSTD_dfast  ",
-                              "ZSTD_greedy ",
-                              "ZSTD_lazy   ",
-                              "ZSTD_lazy2  ",
-                              "ZSTD_btlazy2",
-                              "ZSTD_btopt  ",
-                              "ZSTD_btopt2 "};
+const char* g_stratName[] = { "ZSTD_fast    ",
+                              "ZSTD_dfast   ",
+                              "ZSTD_greedy  ",
+                              "ZSTD_lazy    ",
+                              "ZSTD_lazy2   ",
+                              "ZSTD_btlazy2 ",
+                              "ZSTD_btopt   ",
+                              "ZSTD_btultra "};
 
 static void BMK_printWinner(FILE* f, U32 cLevel, BMK_result_t result, ZSTD_compressionParameters params, size_t srcSize)
 {
@@ -388,8 +390,8 @@ static int BMK_seed(winnerInfo_t* winners, const ZSTD_compressionParameters para
             double W_DMemUsed_note = W_ratioNote * ( 40 + 9*cLevel) - log((double)W_DMemUsed);
             double O_DMemUsed_note = O_ratioNote * ( 40 + 9*cLevel) - log((double)O_DMemUsed);
 
-            size_t W_CMemUsed = (1 << params.windowLog) + ZSTD_estimateCCtxSize(params);
-            size_t O_CMemUsed = (1 << winners[cLevel].params.windowLog) + ZSTD_estimateCCtxSize(winners[cLevel].params);
+            size_t W_CMemUsed = (1 << params.windowLog) + ZSTD_estimateCCtxSize_advanced(params);
+            size_t O_CMemUsed = (1 << winners[cLevel].params.windowLog) + ZSTD_estimateCCtxSize_advanced(winners[cLevel].params);
             double W_CMemUsed_note = W_ratioNote * ( 50 + 13*cLevel) - log((double)W_CMemUsed);
             double O_CMemUsed_note = O_ratioNote * ( 50 + 13*cLevel) - log((double)O_CMemUsed);
 
@@ -454,7 +456,7 @@ static ZSTD_compressionParameters* sanitizeParams(ZSTD_compressionParameters par
         g_params.chainLog = 0, g_params.searchLog = 0;
     if (params.strategy == ZSTD_dfast)
         g_params.searchLog = 0;
-    if (params.strategy != ZSTD_btopt && params.strategy != ZSTD_btopt2)
+    if (params.strategy != ZSTD_btopt && params.strategy != ZSTD_btultra)
         g_params.targetLength = 0;
     return &g_params;
 }
@@ -558,7 +560,7 @@ static ZSTD_compressionParameters randomParams(void)
         p.windowLog  = FUZ_rand(&g_rand) % (ZSTD_WINDOWLOG_MAX+1 - ZSTD_WINDOWLOG_MIN) + ZSTD_WINDOWLOG_MIN;
         p.searchLength=FUZ_rand(&g_rand) % (ZSTD_SEARCHLENGTH_MAX+1 - ZSTD_SEARCHLENGTH_MIN) + ZSTD_SEARCHLENGTH_MIN;
         p.targetLength=FUZ_rand(&g_rand) % (ZSTD_TARGETLENGTH_MAX+1 - ZSTD_TARGETLENGTH_MIN) + ZSTD_TARGETLENGTH_MIN;
-        p.strategy   = (ZSTD_strategy) (FUZ_rand(&g_rand) % (ZSTD_btopt2 +1));
+        p.strategy   = (ZSTD_strategy) (FUZ_rand(&g_rand) % (ZSTD_btultra +1));
         validated = !ZSTD_isError(ZSTD_checkCParams(p));
     }
     return p;
diff --git a/tests/playTests.sh b/tests/playTests.sh
index 021fd59fe2af..2e1cc6826f11 100755
--- a/tests/playTests.sh
+++ b/tests/playTests.sh
@@ -92,7 +92,7 @@ $ZSTD tmp --stdout > tmpCompressed       # long command format
 $ECHO "test : compress to named file"
 rm tmpCompressed
 $ZSTD tmp -o tmpCompressed
-ls tmpCompressed   # must work
+test -f tmpCompressed   # file must be created
 $ECHO "test : -o must be followed by filename (must fail)"
 $ZSTD tmp -of tmpCompressed && die "-o must be followed by filename "
 $ECHO "test : force write, correct order"
@@ -142,21 +142,21 @@ $ZSTD -q -f tmpro
 rm -f tmpro tmpro.zst
 $ECHO "test : file removal"
 $ZSTD -f --rm tmp
-ls tmp && die "tmp should no longer be present"
+test ! -f tmp  # tmp should no longer be present
 $ZSTD -f -d --rm tmp.zst
-ls tmp.zst && die "tmp.zst should no longer be present"
+test ! -f tmp.zst   # tmp.zst should no longer be present
 $ECHO "test : --rm on stdin"
 $ECHO a | $ZSTD --rm > $INTOVOID   # --rm should remain silent
 rm tmp
 $ZSTD -f tmp && die "tmp not present : should have failed"
-ls tmp.zst && die "tmp.zst should not be created"
+test ! -f tmp.zst  # tmp.zst should not be created
 
 
 $ECHO "\n**** Advanced compression parameters **** "
 $ECHO "Hello world!" | $ZSTD --zstd=windowLog=21,      - -o tmp.zst && die "wrong parameters not detected!"
 $ECHO "Hello world!" | $ZSTD --zstd=windowLo=21        - -o tmp.zst && die "wrong parameters not detected!"
 $ECHO "Hello world!" | $ZSTD --zstd=windowLog=21,slog  - -o tmp.zst && die "wrong parameters not detected!"
-ls tmp.zst && die "tmp.zst should not be created"
+test ! -f tmp.zst  # tmp.zst should not be created
 roundTripTest -g512K
 roundTripTest -g512K " --zstd=slen=3,tlen=48,strat=6"
 roundTripTest -g512K " --zstd=strat=6,wlog=23,clog=23,hlog=22,slog=6"
@@ -201,16 +201,17 @@ $ECHO foo | $ZSTD > /dev/full && die "write error not detected!"
 $ECHO "$ECHO foo | $ZSTD | $ZSTD -d > /dev/full"
 $ECHO foo | $ZSTD | $ZSTD -d > /dev/full && die "write error not detected!"
 
+
 $ECHO "\n**** symbolic link test **** "
 
 rm -f hello.tmp world.tmp hello.tmp.zst world.tmp.zst
 $ECHO "hello world" > hello.tmp
 ln -s hello.tmp world.tmp
 $ZSTD world.tmp hello.tmp
-ls hello.tmp.zst || die "regular file should have been compressed!"
-ls world.tmp.zst && die "symbolic link should not have been compressed!"
+test -f hello.tmp.zst  # regular file should have been compressed!
+test ! -f world.tmp.zst  # symbolic link should not have been compressed!
 $ZSTD world.tmp hello.tmp -f
-ls world.tmp.zst || die "symbol link should have been compressed with --force"
+test -f world.tmp.zst  # symbolic link should have been compressed with --force
 rm -f hello.tmp world.tmp hello.tmp.zst world.tmp.zst
 
 fi
@@ -225,10 +226,10 @@ $ZSTD tmpSparse -c | $ZSTD -dv --sparse -c > tmpOutSparse
 $DIFF -s tmpSparse tmpOutSparse
 $ZSTD tmpSparse -c | $ZSTD -dv --no-sparse -c > tmpOutNoSparse
 $DIFF -s tmpSparse tmpOutNoSparse
-ls -ls tmpSparse*
+ls -ls tmpSparse*  # look at file size and block size on disk
 ./datagen -s1 -g1200007 -P100 | $ZSTD | $ZSTD -dv --sparse -c > tmpSparseOdd   # Odd size file (to not finish on an exact nb of blocks)
 ./datagen -s1 -g1200007 -P100 | $DIFF -s - tmpSparseOdd
-ls -ls tmpSparseOdd
+ls -ls tmpSparseOdd  # look at file size and block size on disk
 $ECHO "\n Sparse Compatibility with Console :"
 $ECHO "Hello World 1 !" | $ZSTD | $ZSTD -d -c
 $ECHO "Hello World 2 !" | $ZSTD | $ZSTD -d | cat
@@ -238,7 +239,7 @@ cat tmpSparse1M tmpSparse1M > tmpSparse2M
 $ZSTD -v -f tmpSparse1M -o tmpSparseCompressed
 $ZSTD -d -v -f tmpSparseCompressed -o tmpSparseRegenerated
 $ZSTD -d -v -f tmpSparseCompressed -c >> tmpSparseRegenerated
-ls -ls tmpSparse*
+ls -ls tmpSparse*  # look at file size and block size on disk
 $DIFF tmpSparse2M tmpSparseRegenerated
 rm tmpSparse*
 
@@ -257,11 +258,11 @@ $ZSTD -df *.zst
 ls -ls tmp*
 $ECHO "compress tmp* into stdout > tmpall : "
 $ZSTD -c tmp1 tmp2 tmp3 > tmpall
-ls -ls tmp*
+ls -ls tmp*  # check size of tmpall (should be tmp1.zst + tmp2.zst + tmp3.zst)
 $ECHO "decompress tmpall* into stdout > tmpdec : "
 cp tmpall tmpall2
 $ZSTD -dc tmpall* > tmpdec
-ls -ls tmp*
+ls -ls tmp* # check size of tmpdec (should be 2*(tmp1 + tmp2 + tmp3))
 $ECHO "compress multiple files including a missing one (notHere) : "
 $ZSTD -f tmp1 notHere tmp2 && die "missing file not detected!"
 
@@ -379,7 +380,9 @@ $ZSTD -t tmp2.zst && die "bad file not detected !"
 $ZSTD -t tmp3 && die "bad file not detected !"   # detects 0-sized files as bad
 $ECHO "test --rm and --test combined "
 $ZSTD -t --rm tmp1.zst
-ls -ls tmp1.zst  # check file is still present
+test -f tmp1.zst   # check file is still present
+split -b16384 tmp1.zst tmpSplit.
+$ZSTD -t tmpSplit.* && die "bad file not detected !"
 
 
 $ECHO "\n**** benchmark mode tests **** "
@@ -439,6 +442,7 @@ if [ $LZMAMODE -eq 1 ]; then
     XZEXE=1
     xz -V && lzma -V || XZEXE=0
     if [ $XZEXE -eq 1 ]; then
+        $ECHO "Testing zstd xz and lzma support"
         ./datagen > tmp
         $ZSTD --format=lzma -f tmp
         $ZSTD --format=xz -f tmp
@@ -449,6 +453,24 @@ if [ $LZMAMODE -eq 1 ]; then
         $ZSTD -d -f -v tmp.xz
         $ZSTD -d -f -v tmp.lzma
         rm tmp*
+        $ECHO "Creating symlinks"
+        ln -s $ZSTD ./xz
+        ln -s $ZSTD ./unxz
+        ln -s $ZSTD ./lzma
+        ln -s $ZSTD ./unlzma
+        $ECHO "Testing xz and lzma symlinks"
+        ./datagen > tmp
+        ./xz tmp
+        xz -d tmp.xz
+        ./lzma tmp
+        lzma -d tmp.lzma
+        $ECHO "Testing unxz and unlzma symlinks"
+        xz tmp
+        ./xz -d tmp.xz
+        lzma tmp
+        ./lzma -d tmp.lzma
+        rm xz unxz lzma unlzma
+        rm tmp*
     else
         $ECHO "xz binary not detected"
     fi
@@ -534,6 +556,54 @@ fi
 
 rm tmp*
 
+$ECHO "\n**** zstd --list/-l single frame tests ****"
+./datagen > tmp1
+./datagen > tmp2
+./datagen > tmp3
+./datagen > tmp4
+$ZSTD tmp*
+$ZSTD -l *.zst
+$ZSTD -lv *.zst
+$ZSTD --list *.zst
+$ZSTD --list -v *.zst
+
+$ECHO "\n**** zstd --list/-l multiple frame tests ****"
+cat tmp1.zst tmp2.zst > tmp12.zst
+cat tmp3.zst tmp4.zst > tmp34.zst
+cat tmp12.zst tmp34.zst > tmp1234.zst
+cat tmp12.zst tmp4.zst > tmp124.zst
+$ZSTD -l *.zst
+$ZSTD -lv *.zst
+$ZSTD --list *.zst
+$ZSTD --list -v *.zst
+
+$ECHO "\n**** zstd --list/-l error detection tests ****"
+! $ZSTD -l tmp1 tmp1.zst
+! $ZSTD --list tmp*
+! $ZSTD -lv tmp1*
+! $ZSTD --list -v tmp2 tmp23.zst
+
+$ECHO "\n**** zstd --list/-l test with null files ****"
+./datagen -g0 > tmp5
+$ZSTD tmp5
+$ZSTD -l tmp5.zst
+! $ZSTD -l tmp5*
+$ZSTD -lv tmp5.zst
+! $ZSTD -lv tmp5*
+
+$ECHO "\n**** zstd --list/-l test with no content size field ****"
+./datagen -g1MB | $ZSTD > tmp6.zst
+$ZSTD -l tmp6.zst
+$ZSTD -lv tmp6.zst
+
+$ECHO "\n**** zstd --list/-l test with no checksum ****"
+$ZSTD -f --no-check tmp1
+$ZSTD -l tmp1.zst
+$ZSTD -lv tmp1.zst
+
+rm tmp*
+
+
 if [ "$1" != "--test-large-data" ]; then
     $ECHO "Skipping large data tests"
     exit 0
diff --git a/tests/roundTripCrash.c b/tests/roundTripCrash.c
index a296d4160e55..77c6737eebdb 100644
--- a/tests/roundTripCrash.c
+++ b/tests/roundTripCrash.c
@@ -68,13 +68,20 @@ static size_t checkBuffers(const void* buff1, const void* buff2, size_t buffSize
     return pos;
 }
 
+static void crash(int errorCode){
+    /* abort if AFL/libfuzzer, exit otherwise */
+    #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION /* could also use __AFL_COMPILER */
+        abort();
+    #else
+        exit(errorCode);
+    #endif
+}
 
 static void roundTripCheck(const void* srcBuff, size_t srcBuffSize)
 {
     size_t const cBuffSize = ZSTD_compressBound(srcBuffSize);
     void* cBuff = malloc(cBuffSize);
     void* rBuff = malloc(cBuffSize);
-    #define CRASH { free(cBuff); free(cBuff); }   /* double free, to crash program */
 
     if (!cBuff || !rBuff) {
         fprintf(stderr, "not enough memory ! \n");
@@ -84,15 +91,15 @@ static void roundTripCheck(const void* srcBuff, size_t srcBuffSize)
     {   size_t const result = roundTripTest(rBuff, cBuffSize, cBuff, cBuffSize, srcBuff, srcBuffSize);
         if (ZSTD_isError(result)) {
             fprintf(stderr, "roundTripTest error : %s \n", ZSTD_getErrorName(result));
-            CRASH;
+            crash(1);
         }
         if (result != srcBuffSize) {
             fprintf(stderr, "Incorrect regenerated size : %u != %u\n", (unsigned)result, (unsigned)srcBuffSize);
-            CRASH;
+            crash(1);
         }
         if (checkBuffers(srcBuff, rBuff, srcBuffSize) != srcBuffSize) {
             fprintf(stderr, "Silent decoding corruption !!!");
-            CRASH;
+            crash(1);
         }
     }
 
diff --git a/tests/symbols.c b/tests/symbols.c
index 7dacfc05892d..8920187f37f7 100644
--- a/tests/symbols.c
+++ b/tests/symbols.c
@@ -88,14 +88,14 @@ static const void *symbols[] = {
   &ZSTD_copyCCtx,
   &ZSTD_compressContinue,
   &ZSTD_compressEnd,
-  &ZSTD_getFrameParams,
+  &ZSTD_getFrameHeader,
   &ZSTD_decompressBegin,
   &ZSTD_decompressBegin_usingDict,
   &ZSTD_copyDCtx,
   &ZSTD_nextSrcSizeToDecompress,
   &ZSTD_decompressContinue,
   &ZSTD_nextInputType,
-  &ZSTD_getBlockSizeMax,
+  &ZSTD_getBlockSize,
   &ZSTD_compressBlock,
   &ZSTD_decompressBlock,
   &ZSTD_insertBlock,
@@ -131,7 +131,10 @@ static const void *symbols[] = {
   &ZDICT_isError,
   &ZDICT_getErrorName,
 /* zdict.h: advanced functions */
-  &ZDICT_trainFromBuffer_advanced,
+  &ZDICT_trainFromBuffer_cover,
+  &ZDICT_optimizeTrainFromBuffer_cover,
+  &ZDICT_finalizeDictionary,
+  &ZDICT_trainFromBuffer_legacy,
   &ZDICT_addEntropyTablesFromBuffer,
   NULL,
 };
diff --git a/tests/zstreamtest.c b/tests/zstreamtest.c
index 0e09e185642b..9b2b8eaf81b7 100644
--- a/tests/zstreamtest.c
+++ b/tests/zstreamtest.c
@@ -12,9 +12,9 @@
 *  Compiler specific
 **************************************/
 #ifdef _MSC_VER    /* Visual Studio */
-#  define _CRT_SECURE_NO_WARNINGS     /* fgets */
-#  pragma warning(disable : 4127)     /* disable: C4127: conditional expression is constant */
-#  pragma warning(disable : 4146)     /* disable: C4146: minus unsigned expression */
+#  define _CRT_SECURE_NO_WARNINGS   /* fgets */
+#  pragma warning(disable : 4127)   /* disable: C4127: conditional expression is constant */
+#  pragma warning(disable : 4146)   /* disable: C4146: minus unsigned expression */
 #endif
 
 
@@ -25,8 +25,9 @@
 #include <stdio.h>        /* fgets, sscanf */
 #include <time.h>         /* clock_t, clock() */
 #include <string.h>       /* strcmp */
+#include <assert.h>       /* assert */
 #include "mem.h"
-#define ZSTD_STATIC_LINKING_ONLY   /* ZSTD_maxCLevel, ZSTD_customMem, ZSTD_getDictID_fromFrame */
+#define ZSTD_STATIC_LINKING_ONLY  /* ZSTD_maxCLevel, ZSTD_customMem, ZSTD_getDictID_fromFrame */
 #include "zstd.h"         /* ZSTD_compressBound */
 #include "zstd_errors.h"  /* ZSTD_error_srcSize_wrong */
 #include "zstdmt_compress.h"
@@ -44,6 +45,7 @@
 #define GB *(1U<<30)
 
 static const U32 nbTestsDefault = 10000;
+static const U32 g_cLevelMax_smallTests = 10;
 #define COMPRESSIBLE_NOISE_LENGTH (10 MB)
 #define FUZ_COMPRESSIBILITY_DEFAULT 50
 static const U32 prime32 = 2654435761U;
@@ -53,13 +55,15 @@ static const U32 prime32 = 2654435761U;
 *  Display Macros
 **************************************/
 #define DISPLAY(...)          fprintf(stderr, __VA_ARGS__)
-#define DISPLAYLEVEL(l, ...)  if (g_displayLevel>=l) { DISPLAY(__VA_ARGS__); }
+#define DISPLAYLEVEL(l, ...)  if (g_displayLevel>=l) {                     \
+                                  DISPLAY(__VA_ARGS__);                    \
+                                  if (g_displayLevel>=4) fflush(stderr); }
 static U32 g_displayLevel = 2;
 
 #define DISPLAYUPDATE(l, ...) if (g_displayLevel>=l) { \
             if ((FUZ_GetClockSpan(g_displayClock) > g_refreshRate) || (g_displayLevel>=4)) \
             { g_displayClock = clock(); DISPLAY(__VA_ARGS__); \
-            if (g_displayLevel>=4) fflush(stderr); } }
+              if (g_displayLevel>=4) fflush(stderr); } }
 static const clock_t g_refreshRate = CLOCKS_PER_SEC / 6;
 static clock_t g_displayClock = 0;
 
@@ -155,12 +159,13 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
     void* decodedBuffer = malloc(decodedBufferSize);
     size_t cSize;
     int testResult = 0;
-    U32 testNb=0;
+    U32 testNb = 1;
     ZSTD_CStream* zc = ZSTD_createCStream_advanced(customMem);
     ZSTD_DStream* zd = ZSTD_createDStream_advanced(customMem);
     ZSTD_inBuffer  inBuff, inBuff2;
     ZSTD_outBuffer outBuff;
     buffer_t dictionary = g_nullBuffer;
+    size_t const dictSize = 128 KB;
     unsigned dictID = 0;
 
     /* Create compressible test buffer */
@@ -186,7 +191,8 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
 
     /* Basic compression test */
     DISPLAYLEVEL(3, "test%3i : compress %u bytes : ", testNb++, COMPRESSIBLE_NOISE_LENGTH);
-    ZSTD_initCStream_usingDict(zc, CNBuffer, 128 KB, 1);
+    { size_t const r = ZSTD_initCStream_usingDict(zc, CNBuffer, dictSize, 1);
+      if (ZSTD_isError(r)) goto _output_error; }
     outBuff.dst = (char*)(compressedBuffer)+cSize;
     outBuff.size = compressedBufferSize;
     outBuff.pos = 0;
@@ -201,10 +207,20 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
     cSize += outBuff.pos;
     DISPLAYLEVEL(3, "OK (%u bytes : %.2f%%)\n", (U32)cSize, (double)cSize/COMPRESSIBLE_NOISE_LENGTH*100);
 
-    DISPLAYLEVEL(3, "test%3i : check CStream size : ", testNb++);
-    { size_t const s = ZSTD_sizeof_CStream(zc);
-      if (ZSTD_isError(s)) goto _output_error;
-      DISPLAYLEVEL(3, "OK (%u bytes) \n", (U32)s);
+    /* context size functions */
+    DISPLAYLEVEL(3, "test%3i : estimate CStream size : ", testNb++);
+    {   ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBufferSize, dictSize);
+        size_t const s = ZSTD_estimateCStreamSize_advanced(cParams)
+                        /* uses ZSTD_initCStream_usingDict() */
+                       + ZSTD_estimateCDictSize_advanced(dictSize, cParams, 0);
+            if (ZSTD_isError(s)) goto _output_error;
+            DISPLAYLEVEL(3, "OK (%u bytes) \n", (U32)s);
+    }
+
+    DISPLAYLEVEL(3, "test%3i : check actual CStream size : ", testNb++);
+    {   size_t const s = ZSTD_sizeof_CStream(zc);
+        if (ZSTD_isError(s)) goto _output_error;
+        DISPLAYLEVEL(3, "OK (%u bytes) \n", (U32)s);
     }
 
     /* Attempt bad compression parameters */
@@ -219,22 +235,25 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
 
     /* skippable frame test */
     DISPLAYLEVEL(3, "test%3i : decompress skippable frame : ", testNb++);
-    ZSTD_initDStream_usingDict(zd, CNBuffer, 128 KB);
+    if (ZSTD_isError( ZSTD_initDStream_usingDict(zd, CNBuffer, dictSize) ))
+        goto _output_error;
     inBuff.src = compressedBuffer;
     inBuff.size = cSize;
     inBuff.pos = 0;
     outBuff.dst = decodedBuffer;
     outBuff.size = CNBufferSize;
     outBuff.pos = 0;
-    { size_t const r = ZSTD_decompressStream(zd, &outBuff, &inBuff);
-      if (r != 0) goto _output_error; }
+    {   size_t const r = ZSTD_decompressStream(zd, &outBuff, &inBuff);
+        DISPLAYLEVEL(5, " ( ZSTD_decompressStream => %u ) ", (U32)r);
+        if (r != 0) goto _output_error;
+    }
     if (outBuff.pos != 0) goto _output_error;   /* skippable frame output len is 0 */
     DISPLAYLEVEL(3, "OK \n");
 
     /* Basic decompression test */
     inBuff2 = inBuff;
     DISPLAYLEVEL(3, "test%3i : decompress %u bytes : ", testNb++, COMPRESSIBLE_NOISE_LENGTH);
-    ZSTD_initDStream_usingDict(zd, CNBuffer, 128 KB);
+    ZSTD_initDStream_usingDict(zd, CNBuffer, dictSize);
     { size_t const r = ZSTD_setDStreamParameter(zd, DStream_p_maxWindowSize, 1000000000);  /* large limit */
       if (ZSTD_isError(r)) goto _output_error; }
     { size_t const remaining = ZSTD_decompressStream(zd, &outBuff, &inBuff);
@@ -260,7 +279,21 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
     }   }
     DISPLAYLEVEL(3, "OK \n");
 
-    DISPLAYLEVEL(3, "test%3i : check DStream size : ", testNb++);
+    /* context size functions */
+    DISPLAYLEVEL(3, "test%3i : estimate DStream size : ", testNb++);
+    {   ZSTD_frameHeader fhi;
+        const void* cStart = (char*)compressedBuffer + (skippableFrameSize + 8);
+        size_t const gfhError = ZSTD_getFrameHeader(&fhi, cStart, cSize);
+        if (gfhError!=0) goto _output_error;
+        DISPLAYLEVEL(5, " (windowSize : %u) ", (U32)fhi.windowSize);
+        {   size_t const s = ZSTD_estimateDStreamSize(fhi.windowSize)
+                            /* uses ZSTD_initDStream_usingDict() */
+                           + ZSTD_estimateDDictSize(dictSize, 0);
+            if (ZSTD_isError(s)) goto _output_error;
+            DISPLAYLEVEL(3, "OK (%u bytes) \n", (U32)s);
+    }   }
+
+    DISPLAYLEVEL(3, "test%3i : check actual DStream size : ", testNb++);
     { size_t const s = ZSTD_sizeof_DStream(zd);
       if (ZSTD_isError(s)) goto _output_error;
       DISPLAYLEVEL(3, "OK (%u bytes) \n", (U32)s);
@@ -270,7 +303,7 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
     DISPLAYLEVEL(3, "test%3i : decompress byte-by-byte : ", testNb++);
     {   /* skippable frame */
         size_t r = 1;
-        ZSTD_initDStream_usingDict(zd, CNBuffer, 128 KB);
+        ZSTD_initDStream_usingDict(zd, CNBuffer, dictSize);
         inBuff.src = compressedBuffer;
         outBuff.dst = decodedBuffer;
         inBuff.pos = 0;
@@ -282,7 +315,7 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
             if (ZSTD_isError(r)) goto _output_error;
         }
         /* normal frame */
-        ZSTD_initDStream_usingDict(zd, CNBuffer, 128 KB);
+        ZSTD_initDStream_usingDict(zd, CNBuffer, dictSize);
         r=1;
         while (r) {
             inBuff.size = inBuff.pos + 1;
@@ -344,6 +377,7 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
     if (zc==NULL) goto _output_error;   /* memory allocation issue */
     /* use 1 */
     {   size_t const inSize = 513;
+        DISPLAYLEVEL(5, "use1 ");
         ZSTD_initCStream_advanced(zc, NULL, 0, ZSTD_getParams(19, inSize, 0), inSize);   /* needs btopt + search3 to trigger hashLog3 */
         inBuff.src = CNBuffer;
         inBuff.size = inSize;
@@ -351,14 +385,17 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
         outBuff.dst = (char*)(compressedBuffer)+cSize;
         outBuff.size = ZSTD_compressBound(inSize);
         outBuff.pos = 0;
+        DISPLAYLEVEL(5, "compress1 ");
         { size_t const r = ZSTD_compressStream(zc, &outBuff, &inBuff);
             if (ZSTD_isError(r)) goto _output_error; }
         if (inBuff.pos != inBuff.size) goto _output_error;   /* entire input should be consumed */
+        DISPLAYLEVEL(5, "end1 ");
         { size_t const r = ZSTD_endStream(zc, &outBuff);
             if (r != 0) goto _output_error; }  /* error, or some data not flushed */
     }
     /* use 2 */
     {   size_t const inSize = 1025;   /* will not continue, because tables auto-adjust and are therefore different size */
+        DISPLAYLEVEL(5, "use2 ");
         ZSTD_initCStream_advanced(zc, NULL, 0, ZSTD_getParams(19, inSize, 0), inSize);   /* needs btopt + search3 to trigger hashLog3 */
         inBuff.src = CNBuffer;
         inBuff.size = inSize;
@@ -366,9 +403,11 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
         outBuff.dst = (char*)(compressedBuffer)+cSize;
         outBuff.size = ZSTD_compressBound(inSize);
         outBuff.pos = 0;
+        DISPLAYLEVEL(5, "compress2 ");
         { size_t const r = ZSTD_compressStream(zc, &outBuff, &inBuff);
             if (ZSTD_isError(r)) goto _output_error; }
         if (inBuff.pos != inBuff.size) goto _output_error;   /* entire input should be consumed */
+        DISPLAYLEVEL(5, "end2 ");
         { size_t const r = ZSTD_endStream(zc, &outBuff);
             if (r != 0) goto _output_error; }  /* error, or some data not flushed */
     }
@@ -376,7 +415,7 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
 
     /* CDict scenario */
     DISPLAYLEVEL(3, "test%3i : digested dictionary : ", testNb++);
-    {   ZSTD_CDict* const cdict = ZSTD_createCDict(dictionary.start, dictionary.filled, 1);
+    {   ZSTD_CDict* const cdict = ZSTD_createCDict(dictionary.start, dictionary.filled, 1 /*byRef*/ );
         size_t const initError = ZSTD_initCStream_usingCDict(zc, cdict);
         if (ZSTD_isError(initError)) goto _output_error;
         cSize = 0;
@@ -435,7 +474,7 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
 
     /* Memory restriction */
     DISPLAYLEVEL(3, "test%3i : maxWindowSize < frame requirement : ", testNb++);
-    ZSTD_initDStream_usingDict(zd, CNBuffer, 128 KB);
+    ZSTD_initDStream_usingDict(zd, CNBuffer, dictSize);
     { size_t const r = ZSTD_setDStreamParameter(zd, DStream_p_maxWindowSize, 1000);  /* too small limit */
       if (ZSTD_isError(r)) goto _output_error; }
     inBuff.src = compressedBuffer;
@@ -451,8 +490,8 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
     DISPLAYLEVEL(3, "test%3i : ZSTD_initCStream_usingCDict_advanced with masked dictID : ", testNb++);
     {   ZSTD_compressionParameters const cParams = ZSTD_getCParams(1, CNBufferSize, dictionary.filled);
         ZSTD_frameParameters const fParams = { 1 /* contentSize */, 1 /* checksum */, 1 /* noDictID */};
-        ZSTD_CDict* const cdict = ZSTD_createCDict_advanced(dictionary.start, dictionary.filled, 1 /* byReference */, cParams, customMem);
-        size_t const initError = ZSTD_initCStream_usingCDict_advanced(zc, cdict, CNBufferSize, fParams);
+        ZSTD_CDict* const cdict = ZSTD_createCDict_advanced(dictionary.start, dictionary.filled, 1 /* byReference */, ZSTD_dm_auto, cParams, customMem);
+        size_t const initError = ZSTD_initCStream_usingCDict_advanced(zc, cdict, fParams, CNBufferSize);
         if (ZSTD_isError(initError)) goto _output_error;
         cSize = 0;
         outBuff.dst = compressedBuffer;
@@ -463,7 +502,7 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
         inBuff.pos = 0;
         { size_t const r = ZSTD_compressStream(zc, &outBuff, &inBuff);
           if (ZSTD_isError(r)) goto _output_error; }
-        if (inBuff.pos != inBuff.size) goto _output_error;   /* entire input should be consumed */
+        if (inBuff.pos != inBuff.size) goto _output_error;  /* entire input should be consumed */
         { size_t const r = ZSTD_endStream(zc, &outBuff);
           if (r != 0) goto _output_error; }  /* error, or some data not flushed */
         cSize = outBuff.pos;
@@ -483,6 +522,55 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
         DISPLAYLEVEL(3, "OK (%s)\n", ZSTD_getErrorName(r));
     }
 
+    DISPLAYLEVEL(3, "test%3i : compress with ZSTD_CCtx_refPrefix : ", testNb++);
+    { size_t const refErr = ZSTD_CCtx_refPrefix(zc, dictionary.start, dictionary.filled);
+      if (ZSTD_isError(refErr)) goto _output_error; }
+    outBuff.dst = compressedBuffer;
+    outBuff.size = compressedBufferSize;
+    outBuff.pos = 0;
+    inBuff.src = CNBuffer;
+    inBuff.size = CNBufferSize;
+    inBuff.pos = 0;
+    { size_t const r = ZSTD_compress_generic(zc, &outBuff, &inBuff, ZSTD_e_end);
+      if (ZSTD_isError(r)) goto _output_error; }
+    if (inBuff.pos != inBuff.size) goto _output_error;  /* entire input should be consumed */
+    cSize = outBuff.pos;
+    DISPLAYLEVEL(3, "OK (%u bytes : %.2f%%)\n", (U32)cSize, (double)cSize/CNBufferSize*100);
+
+    DISPLAYLEVEL(3, "test%3i : decompress with dictionary : ", testNb++);
+    {   size_t const r = ZSTD_decompress_usingDict(zd,
+                                        decodedBuffer, CNBufferSize,
+                                        compressedBuffer, cSize,
+                                        dictionary.start, dictionary.filled);
+        if (ZSTD_isError(r)) goto _output_error;  /* must fail : dictionary not used */
+        DISPLAYLEVEL(3, "OK \n");
+    }
+
+    DISPLAYLEVEL(3, "test%3i : decompress without dictionary (should fail): ", testNb++);
+    {   size_t const r = ZSTD_decompress(decodedBuffer, CNBufferSize, compressedBuffer, cSize);
+        if (!ZSTD_isError(r)) goto _output_error;  /* must fail : dictionary not used */
+        DISPLAYLEVEL(3, "OK (%s)\n", ZSTD_getErrorName(r));
+    }
+
+    DISPLAYLEVEL(3, "test%3i : compress again with ZSTD_compress_generic : ", testNb++);
+    outBuff.dst = compressedBuffer;
+    outBuff.size = compressedBufferSize;
+    outBuff.pos = 0;
+    inBuff.src = CNBuffer;
+    inBuff.size = CNBufferSize;
+    inBuff.pos = 0;
+    { size_t const r = ZSTD_compress_generic(zc, &outBuff, &inBuff, ZSTD_e_end);
+      if (ZSTD_isError(r)) goto _output_error; }
+    if (inBuff.pos != inBuff.size) goto _output_error;  /* entire input should be consumed */
+    cSize = outBuff.pos;
+    DISPLAYLEVEL(3, "OK (%u bytes : %.2f%%)\n", (U32)cSize, (double)cSize/CNBufferSize*100);
+
+    DISPLAYLEVEL(3, "test%3i : decompress without dictionary (should work): ", testNb++);
+    {   size_t const r = ZSTD_decompress(decodedBuffer, CNBufferSize, compressedBuffer, cSize);
+        if (ZSTD_isError(r)) goto _output_error;  /* must fail : dictionary not used */
+        DISPLAYLEVEL(3, "OK \n");
+    }
+
     /* Empty srcSize */
     DISPLAYLEVEL(3, "test%3i : ZSTD_initCStream_advanced with pledgedSrcSize=0 and dict : ", testNb++);
     {   ZSTD_parameters params = ZSTD_getParams(5, 0, 0);
@@ -612,12 +700,26 @@ static size_t FUZ_randomLength(U32* seed, U32 maxLog)
 
 #define MIN(a,b)   ( (a) < (b) ? (a) : (b) )
 
-#define CHECK(cond, ...) if (cond) { DISPLAY("Error => "); DISPLAY(__VA_ARGS__); \
-                         DISPLAY(" (seed %u, test nb %u)  \n", seed, testNb); goto _output_error; }
+#define CHECK(cond, ...) {                                   \
+    if (cond) {                                              \
+        DISPLAY("Error => ");                                \
+        DISPLAY(__VA_ARGS__);                                \
+        DISPLAY(" (seed %u, test nb %u)  \n", seed, testNb); \
+        goto _output_error;                                  \
+}   }
+
+#define CHECK_Z(f) {                                         \
+    size_t const err = f;                                    \
+    if (ZSTD_isError(err)) {                                 \
+        DISPLAY("Error => %s : %s ",                         \
+                #f, ZSTD_getErrorName(err));                 \
+        DISPLAY(" (seed %u, test nb %u)  \n", seed, testNb); \
+        goto _output_error;                                  \
+}   }
 
 static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compressibility, int bigTests)
 {
-    static const U32 maxSrcLog = 24;
+    U32 const maxSrcLog = bigTests ? 24 : 22;
     static const U32 maxSampleLog = 19;
     size_t const srcBufferSize = (size_t)1<<maxSrcLog;
     BYTE* cNoiseBuffer[5];
@@ -637,7 +739,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
     const BYTE* dict=NULL;   /* can keep same dict on 2 consecutive tests */
     size_t dictSize = 0;
     U32 oldTestLog = 0;
-    int const cLevelLimiter = bigTests ? 3 : 2;
+    U32 const cLevelMax = bigTests ? (U32)ZSTD_maxCLevel() : g_cLevelMax_smallTests;
 
     /* allocations */
     cNoiseBuffer[0] = (BYTE*)malloc (srcBufferSize);
@@ -680,8 +782,18 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
 
         /* states full reset (deliberately not synchronized) */
         /* some issues can only happen when reusing states */
-        if ((FUZ_rand(&lseed) & 0xFF) == 131) { ZSTD_freeCStream(zc); zc = ZSTD_createCStream(); resetAllowed=0; }
-        if ((FUZ_rand(&lseed) & 0xFF) == 132) { ZSTD_freeDStream(zd); zd = ZSTD_createDStream(); ZSTD_initDStream_usingDict(zd, NULL, 0);  /* ensure at least one init */ }
+        if ((FUZ_rand(&lseed) & 0xFF) == 131) {
+            ZSTD_freeCStream(zc);
+            zc = ZSTD_createCStream();
+            CHECK(zc==NULL, "ZSTD_createCStream : allocation error");
+            resetAllowed=0;
+        }
+        if ((FUZ_rand(&lseed) & 0xFF) == 132) {
+            ZSTD_freeDStream(zd);
+            zd = ZSTD_createDStream();
+            CHECK(zd==NULL, "ZSTD_createDStream : allocation error");
+            CHECK_Z( ZSTD_initDStream_usingDict(zd, NULL, 0) );  /* ensure at least one init */
+        }
 
         /* srcBuffer selection [0-4] */
         {   U32 buffNb = FUZ_rand(&lseed) & 0x7F;
@@ -705,20 +817,20 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
             if (maxTestSize >= srcBufferSize)
                 maxTestSize = srcBufferSize-1;
             {   U64 const pledgedSrcSize = (FUZ_rand(&lseed) & 3) ? 0 : maxTestSize;
-                size_t const resetError = ZSTD_resetCStream(zc, pledgedSrcSize);
-                CHECK(ZSTD_isError(resetError), "ZSTD_resetCStream error : %s", ZSTD_getErrorName(resetError));
+                CHECK_Z( ZSTD_resetCStream(zc, pledgedSrcSize) );
             }
         } else {
             U32 const testLog = FUZ_rand(&lseed) % maxSrcLog;
             U32 const dictLog = FUZ_rand(&lseed) % maxSrcLog;
-            U32 const cLevel = ( FUZ_rand(&lseed) %
+            U32 const cLevelCandidate = ( FUZ_rand(&lseed) %
                                 (ZSTD_maxCLevel() -
-                                (MAX(testLog, dictLog) / cLevelLimiter)))
+                                (MAX(testLog, dictLog) / 3)))
                                  + 1;
+            U32 const cLevel = MIN(cLevelCandidate, cLevelMax);
             maxTestSize = FUZ_rLogLength(&lseed, testLog);
             oldTestLog = testLog;
             /* random dictionary selection */
-            dictSize  = ((FUZ_rand(&lseed)&1)==1) ? FUZ_rLogLength(&lseed, dictLog) : 0;
+            dictSize  = ((FUZ_rand(&lseed)&7)==1) ? FUZ_rLogLength(&lseed, dictLog) : 0;
             {   size_t const dictStart = FUZ_rand(&lseed) % (srcBufferSize - dictSize);
                 dict = srcBuffer + dictStart;
             }
@@ -726,9 +838,8 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
                 ZSTD_parameters params = ZSTD_getParams(cLevel, pledgedSrcSize, dictSize);
                 params.fParams.checksumFlag = FUZ_rand(&lseed) & 1;
                 params.fParams.noDictIDFlag = FUZ_rand(&lseed) & 1;
-                {   size_t const initError = ZSTD_initCStream_advanced(zc, dict, dictSize, params, pledgedSrcSize);
-                    CHECK (ZSTD_isError(initError),"ZSTD_initCStream_advanced error : %s", ZSTD_getErrorName(initError));
-        }   }   }
+                CHECK_Z ( ZSTD_initCStream_advanced(zc, dict, dictSize, params, pledgedSrcSize) );
+        }   }
 
         /* multi-segments compression test */
         XXH64_reset(&xxhState, 0);
@@ -744,8 +855,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
                     ZSTD_inBuffer inBuff = { srcBuffer+srcStart, srcSize, 0 };
                     outBuff.size = outBuff.pos + dstBuffSize;
 
-                    { size_t const compressionError = ZSTD_compressStream(zc, &outBuff, &inBuff);
-                      CHECK (ZSTD_isError(compressionError), "compression error : %s", ZSTD_getErrorName(compressionError)); }
+                    CHECK_Z( ZSTD_compressStream(zc, &outBuff, &inBuff) );
 
                     XXH64_update(&xxhState, srcBuffer+srcStart, inBuff.pos);
                     memcpy(copyBuffer+totalTestSize, srcBuffer+srcStart, inBuff.pos);
@@ -757,20 +867,17 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
                     size_t const randomDstSize = FUZ_randomLength(&lseed, maxSampleLog);
                     size_t const adjustedDstSize = MIN(cBufferSize - cSize, randomDstSize);
                     outBuff.size = outBuff.pos + adjustedDstSize;
-                    {   size_t const flushError = ZSTD_flushStream(zc, &outBuff);
-                        CHECK (ZSTD_isError(flushError), "flush error : %s", ZSTD_getErrorName(flushError));
-            }   }   }
+                    CHECK_Z( ZSTD_flushStream(zc, &outBuff) );
+            }   }
 
             /* final frame epilogue */
             {   size_t remainingToFlush = (size_t)(-1);
                 while (remainingToFlush) {
                     size_t const randomDstSize = FUZ_randomLength(&lseed, maxSampleLog);
                     size_t const adjustedDstSize = MIN(cBufferSize - cSize, randomDstSize);
-                    U32 const enoughDstSize = (adjustedDstSize >= remainingToFlush);
                     outBuff.size = outBuff.pos + adjustedDstSize;
                     remainingToFlush = ZSTD_endStream(zc, &outBuff);
-                    CHECK (ZSTD_isError(remainingToFlush), "flush error : %s", ZSTD_getErrorName(remainingToFlush));
-                    CHECK (enoughDstSize && remainingToFlush, "ZSTD_endStream() not fully flushed (%u remaining), but enough space available", (U32)remainingToFlush);
+                    CHECK (ZSTD_isError(remainingToFlush), "end error : %s", ZSTD_getErrorName(remainingToFlush));
             }   }
             crcOrig = XXH64_digest(&xxhState);
             cSize = outBuff.pos;
@@ -778,9 +885,9 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
 
         /* multi - fragments decompression test */
         if (!dictSize /* don't reset if dictionary : could be different */ && (FUZ_rand(&lseed) & 1)) {
-            CHECK (ZSTD_isError(ZSTD_resetDStream(zd)), "ZSTD_resetDStream failed");
+            CHECK_Z ( ZSTD_resetDStream(zd) );
         } else {
-            ZSTD_initDStream_usingDict(zd, dict, dictSize);
+            CHECK_Z ( ZSTD_initDStream_usingDict(zd, dict, dictSize) );
         }
         {   size_t decompressionResult = 1;
             ZSTD_inBuffer  inBuff = { cBuffer, cSize, 0 };
@@ -815,7 +922,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
         }   }
 
         /* try decompression on noisy data */
-        ZSTD_initDStream(zd_noise);   /* note : no dictionary */
+        CHECK_Z( ZSTD_initDStream(zd_noise) );   /* note : no dictionary */
         {   ZSTD_inBuffer  inBuff = { cBuffer, cSize, 0 };
             ZSTD_outBuffer outBuff= { dstBuffer, dstBufferSize, 0 };
             while (outBuff.pos < dstBufferSize) {
@@ -855,7 +962,7 @@ _output_error:
 /* Multi-threading version of fuzzer Tests */
 static int fuzzerTests_MT(U32 seed, U32 nbTests, unsigned startTest, double compressibility, int bigTests)
 {
-    static const U32 maxSrcLog = 24;
+    const U32 maxSrcLog = bigTests ? 24 : 22;
     static const U32 maxSampleLog = 19;
     size_t const srcBufferSize = (size_t)1<<maxSrcLog;
     BYTE* cNoiseBuffer[5];
@@ -875,7 +982,8 @@ static int fuzzerTests_MT(U32 seed, U32 nbTests, unsigned startTest, double comp
     const BYTE* dict=NULL;   /* can keep same dict on 2 consecutive tests */
     size_t dictSize = 0;
     U32 oldTestLog = 0;
-    int const cLevelLimiter = bigTests ? 3 : 2;
+    U32 const cLevelMax = bigTests ? (U32)ZSTD_maxCLevel() : g_cLevelMax_smallTests;
+    U32 const nbThreadsMax = bigTests ? 5 : 2;
 
     /* allocations */
     cNoiseBuffer[0] = (BYTE*)malloc (srcBufferSize);
@@ -919,15 +1027,18 @@ static int fuzzerTests_MT(U32 seed, U32 nbTests, unsigned startTest, double comp
         /* states full reset (deliberately not synchronized) */
         /* some issues can only happen when reusing states */
         if ((FUZ_rand(&lseed) & 0xFF) == 131) {
-            U32 const nbThreads = (FUZ_rand(&lseed) % 6) + 1;
+            U32 const nbThreadsCandidate = (FUZ_rand(&lseed) % 6) + 1;
+            U32 const nbThreads = MIN(nbThreadsCandidate, nbThreadsMax);
             DISPLAYLEVEL(5, "Creating new context with %u threads \n", nbThreads);
             ZSTDMT_freeCCtx(zc);
             zc = ZSTDMT_createCCtx(nbThreads);
+            CHECK(zc==NULL, "ZSTDMT_createCCtx allocation error")
             resetAllowed=0;
         }
         if ((FUZ_rand(&lseed) & 0xFF) == 132) {
             ZSTD_freeDStream(zd);
             zd = ZSTD_createDStream();
+            CHECK(zd==NULL, "ZSTDMT_createCCtx allocation error")
             ZSTD_initDStream_usingDict(zd, NULL, 0);  /* ensure at least one init */
         }
 
@@ -952,16 +1063,16 @@ static int fuzzerTests_MT(U32 seed, U32 nbTests, unsigned startTest, double comp
             maxTestSize = FUZ_randomLength(&lseed, oldTestLog+2);
             if (maxTestSize >= srcBufferSize) maxTestSize = srcBufferSize-1;
             {   int const compressionLevel = (FUZ_rand(&lseed) % 5) + 1;
-                size_t const resetError = ZSTDMT_initCStream(zc, compressionLevel);
-                CHECK(ZSTD_isError(resetError), "ZSTDMT_initCStream error : %s", ZSTD_getErrorName(resetError));
+                CHECK_Z( ZSTDMT_initCStream(zc, compressionLevel) );
             }
         } else {
             U32 const testLog = FUZ_rand(&lseed) % maxSrcLog;
             U32 const dictLog = FUZ_rand(&lseed) % maxSrcLog;
-            U32 const cLevel = (FUZ_rand(&lseed) %
-                                (ZSTD_maxCLevel() -
-                                 (MAX(testLog, dictLog) / cLevelLimiter))) +
+            U32 const cLevelCandidate = (FUZ_rand(&lseed) %
+                               (ZSTD_maxCLevel() -
+                               (MAX(testLog, dictLog) / 3))) +
                                1;
+            U32 const cLevel = MIN(cLevelCandidate, cLevelMax);
             maxTestSize = FUZ_rLogLength(&lseed, testLog);
             oldTestLog = testLog;
             /* random dictionary selection */
@@ -977,10 +1088,9 @@ static int fuzzerTests_MT(U32 seed, U32 nbTests, unsigned startTest, double comp
                 params.fParams.noDictIDFlag = FUZ_rand(&lseed) & 1;
                 params.fParams.contentSizeFlag = pledgedSrcSize>0;
                 DISPLAYLEVEL(5, "checksumFlag : %u \n", params.fParams.checksumFlag);
-                { size_t const initError = ZSTDMT_initCStream_advanced(zc, dict, dictSize, params, pledgedSrcSize);
-                  CHECK (ZSTD_isError(initError),"ZSTDMT_initCStream_advanced error : %s", ZSTD_getErrorName(initError)); }
-                ZSTDMT_setMTCtxParameter(zc, ZSTDMT_p_overlapSectionLog, FUZ_rand(&lseed) % 12);
-                ZSTDMT_setMTCtxParameter(zc, ZSTDMT_p_sectionSize, FUZ_rand(&lseed) % (2*maxTestSize+1));
+                CHECK_Z( ZSTDMT_initCStream_advanced(zc, dict, dictSize, params, pledgedSrcSize) );
+                CHECK_Z( ZSTDMT_setMTCtxParameter(zc, ZSTDMT_p_overlapSectionLog, FUZ_rand(&lseed) % 12) );
+                CHECK_Z( ZSTDMT_setMTCtxParameter(zc, ZSTDMT_p_sectionSize, FUZ_rand(&lseed) % (2*maxTestSize+1)) );
         }   }
 
         /* multi-segments compression test */
@@ -998,8 +1108,7 @@ static int fuzzerTests_MT(U32 seed, U32 nbTests, unsigned startTest, double comp
                     outBuff.size = outBuff.pos + dstBuffSize;
 
                     DISPLAYLEVEL(5, "Sending %u bytes to compress \n", (U32)srcSize);
-                    { size_t const compressionError = ZSTDMT_compressStream(zc, &outBuff, &inBuff);
-                      CHECK (ZSTD_isError(compressionError), "compression error : %s", ZSTD_getErrorName(compressionError)); }
+                    CHECK_Z( ZSTDMT_compressStream(zc, &outBuff, &inBuff) );
                     DISPLAYLEVEL(5, "%u bytes read by ZSTDMT_compressStream \n", (U32)inBuff.pos);
 
                     XXH64_update(&xxhState, srcBuffer+srcStart, inBuff.pos);
@@ -1013,9 +1122,8 @@ static int fuzzerTests_MT(U32 seed, U32 nbTests, unsigned startTest, double comp
                     size_t const adjustedDstSize = MIN(cBufferSize - cSize, randomDstSize);
                     outBuff.size = outBuff.pos + adjustedDstSize;
                     DISPLAYLEVEL(5, "Flushing into dst buffer of size %u \n", (U32)adjustedDstSize);
-                    {   size_t const flushError = ZSTDMT_flushStream(zc, &outBuff);
-                        CHECK (ZSTD_isError(flushError), "ZSTDMT_flushStream error : %s", ZSTD_getErrorName(flushError));
-            }   }   }
+                    CHECK_Z( ZSTDMT_flushStream(zc, &outBuff) );
+            }   }
 
             /* final frame epilogue */
             {   size_t remainingToFlush = (size_t)(-1);
@@ -1035,9 +1143,9 @@ static int fuzzerTests_MT(U32 seed, U32 nbTests, unsigned startTest, double comp
 
         /* multi - fragments decompression test */
         if (!dictSize /* don't reset if dictionary : could be different */ && (FUZ_rand(&lseed) & 1)) {
-            CHECK (ZSTD_isError(ZSTD_resetDStream(zd)), "ZSTD_resetDStream failed");
+            CHECK_Z( ZSTD_resetDStream(zd) );
         } else {
-            ZSTD_initDStream_usingDict(zd, dict, dictSize);
+            CHECK_Z( ZSTD_initDStream_usingDict(zd, dict, dictSize) );
         }
         {   size_t decompressionResult = 1;
             ZSTD_inBuffer  inBuff = { cBuffer, cSize, 0 };
@@ -1073,7 +1181,7 @@ static int fuzzerTests_MT(U32 seed, U32 nbTests, unsigned startTest, double comp
         }   }
 
         /* try decompression on noisy data */
-        ZSTD_initDStream(zd_noise);   /* note : no dictionary */
+        CHECK_Z( ZSTD_initDStream(zd_noise) );   /* note : no dictionary */
         {   ZSTD_inBuffer  inBuff = { cBuffer, cSize, 0 };
             ZSTD_outBuffer outBuff= { dstBuffer, dstBufferSize, 0 };
             while (outBuff.pos < dstBufferSize) {
@@ -1110,6 +1218,297 @@ _output_error:
 }
 
 
+/* Tests for ZSTD_compress_generic() API */
+static int fuzzerTests_newAPI(U32 seed, U32 nbTests, unsigned startTest, double compressibility, int bigTests)
+{
+    U32 const maxSrcLog = bigTests ? 24 : 22;
+    static const U32 maxSampleLog = 19;
+    size_t const srcBufferSize = (size_t)1<<maxSrcLog;
+    BYTE* cNoiseBuffer[5];
+    size_t const copyBufferSize= srcBufferSize + (1<<maxSampleLog);
+    BYTE*  const copyBuffer = (BYTE*)malloc (copyBufferSize);
+    size_t const cBufferSize   = ZSTD_compressBound(srcBufferSize);
+    BYTE*  const cBuffer = (BYTE*)malloc (cBufferSize);
+    size_t const dstBufferSize = srcBufferSize;
+    BYTE*  const dstBuffer = (BYTE*)malloc (dstBufferSize);
+    U32 result = 0;
+    U32 testNb = 0;
+    U32 coreSeed = seed;
+    ZSTD_CCtx* zc = ZSTD_createCCtx();   /* will be reset sometimes */
+    ZSTD_DStream* zd = ZSTD_createDStream();   /* will be reset sometimes */
+    ZSTD_DStream* const zd_noise = ZSTD_createDStream();
+    clock_t const startClock = clock();
+    const BYTE* dict = NULL;   /* can keep same dict on 2 consecutive tests */
+    size_t dictSize = 0;
+    U32 oldTestLog = 0;
+    U32 const cLevelMax = bigTests ? (U32)ZSTD_maxCLevel() : g_cLevelMax_smallTests;
+    U32 const nbThreadsMax = bigTests ? 5 : 1;
+
+    /* allocations */
+    cNoiseBuffer[0] = (BYTE*)malloc (srcBufferSize);
+    cNoiseBuffer[1] = (BYTE*)malloc (srcBufferSize);
+    cNoiseBuffer[2] = (BYTE*)malloc (srcBufferSize);
+    cNoiseBuffer[3] = (BYTE*)malloc (srcBufferSize);
+    cNoiseBuffer[4] = (BYTE*)malloc (srcBufferSize);
+    CHECK (!cNoiseBuffer[0] || !cNoiseBuffer[1] || !cNoiseBuffer[2] || !cNoiseBuffer[3] || !cNoiseBuffer[4] ||
+           !copyBuffer || !dstBuffer || !cBuffer || !zc || !zd || !zd_noise ,
+           "Not enough memory, fuzzer tests cancelled");
+
+    /* Create initial samples */
+    RDG_genBuffer(cNoiseBuffer[0], srcBufferSize, 0.00, 0., coreSeed);    /* pure noise */
+    RDG_genBuffer(cNoiseBuffer[1], srcBufferSize, 0.05, 0., coreSeed);    /* barely compressible */
+    RDG_genBuffer(cNoiseBuffer[2], srcBufferSize, compressibility, 0., coreSeed);
+    RDG_genBuffer(cNoiseBuffer[3], srcBufferSize, 0.95, 0., coreSeed);    /* highly compressible */
+    RDG_genBuffer(cNoiseBuffer[4], srcBufferSize, 1.00, 0., coreSeed);    /* sparse content */
+    memset(copyBuffer, 0x65, copyBufferSize);                             /* make copyBuffer considered initialized */
+    CHECK_Z( ZSTD_initDStream_usingDict(zd, NULL, 0) );   /* ensure at least one init */
+
+    /* catch up testNb */
+    for (testNb=1; testNb < startTest; testNb++)
+        FUZ_rand(&coreSeed);
+
+    /* test loop */
+    for ( ; (testNb <= nbTests) || (FUZ_GetClockSpan(startClock) < g_clockTime) ; testNb++ ) {
+        U32 lseed;
+        const BYTE* srcBuffer;
+        size_t totalTestSize, totalGenSize, cSize;
+        XXH64_state_t xxhState;
+        U64 crcOrig;
+        U32 resetAllowed = 1;
+        size_t maxTestSize;
+
+        /* init */
+        if (nbTests >= testNb) { DISPLAYUPDATE(2, "\r%6u/%6u    ", testNb, nbTests); }
+        else { DISPLAYUPDATE(2, "\r%6u          ", testNb); }
+        FUZ_rand(&coreSeed);
+        lseed = coreSeed ^ prime32;
+
+        /* states full reset (deliberately not synchronized) */
+        /* some issues can only happen when reusing states */
+        if ((FUZ_rand(&lseed) & 0xFF) == 131) {
+            DISPLAYLEVEL(5, "Creating new context \n");
+            ZSTD_freeCCtx(zc);
+            zc = ZSTD_createCCtx();
+            CHECK(zc==NULL, "ZSTD_createCCtx allocation error");
+            resetAllowed=0;
+        }
+        if ((FUZ_rand(&lseed) & 0xFF) == 132) {
+            ZSTD_freeDStream(zd);
+            zd = ZSTD_createDStream();
+            CHECK(zd==NULL, "ZSTD_createDStream allocation error");
+            ZSTD_initDStream_usingDict(zd, NULL, 0);  /* ensure at least one init */
+        }
+
+        /* srcBuffer selection [0-4] */
+        {   U32 buffNb = FUZ_rand(&lseed) & 0x7F;
+            if (buffNb & 7) buffNb=2;   /* most common : compressible (P) */
+            else {
+                buffNb >>= 3;
+                if (buffNb & 7) {
+                    const U32 tnb[2] = { 1, 3 };   /* barely/highly compressible */
+                    buffNb = tnb[buffNb >> 3];
+                } else {
+                    const U32 tnb[2] = { 0, 4 };   /* not compressible / sparse */
+                    buffNb = tnb[buffNb >> 3];
+            }   }
+            srcBuffer = cNoiseBuffer[buffNb];
+        }
+
+        /* compression init */
+        CHECK_Z( ZSTD_CCtx_loadDictionary(zc, NULL, 0) );   /* cancel previous dict /*/
+        if ((FUZ_rand(&lseed)&1) /* at beginning, to keep same nb of rand */
+            && oldTestLog /* at least one test happened */ && resetAllowed) {
+            maxTestSize = FUZ_randomLength(&lseed, oldTestLog+2);
+            if (maxTestSize >= srcBufferSize) maxTestSize = srcBufferSize-1;
+            {   int const compressionLevel = (FUZ_rand(&lseed) % 5) + 1;
+                CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_compressionLevel, compressionLevel) );
+            }
+        } else {
+            U32 const testLog = FUZ_rand(&lseed) % maxSrcLog;
+            U32 const dictLog = FUZ_rand(&lseed) % maxSrcLog;
+            U32 const cLevelCandidate = (FUZ_rand(&lseed) %
+                               (ZSTD_maxCLevel() -
+                               (MAX(testLog, dictLog) / 3))) +
+                               1;
+            U32 const cLevel = MIN(cLevelCandidate, cLevelMax);
+            maxTestSize = FUZ_rLogLength(&lseed, testLog);
+            oldTestLog = testLog;
+            /* random dictionary selection */
+            dictSize  = ((FUZ_rand(&lseed)&63)==1) ? FUZ_rLogLength(&lseed, dictLog) : 0;
+            {   size_t const dictStart = FUZ_rand(&lseed) % (srcBufferSize - dictSize);
+                dict = srcBuffer + dictStart;
+                if (!dictSize) dict=NULL;
+            }
+            {   U64 const pledgedSrcSize = (FUZ_rand(&lseed) & 3) ? ZSTD_CONTENTSIZE_UNKNOWN : maxTestSize;
+                ZSTD_compressionParameters cParams = ZSTD_getCParams(cLevel, pledgedSrcSize, dictSize);
+
+                /* mess with compression parameters */
+                cParams.windowLog += (FUZ_rand(&lseed) & 3) - 1;
+                cParams.hashLog += (FUZ_rand(&lseed) & 3) - 1;
+                cParams.chainLog += (FUZ_rand(&lseed) & 3) - 1;
+                cParams.searchLog += (FUZ_rand(&lseed) & 3) - 1;
+                cParams.searchLength += (FUZ_rand(&lseed) & 3) - 1;
+                cParams.targetLength = (U32)(cParams.targetLength * (0.5 + ((double)(FUZ_rand(&lseed) & 127) / 128)));
+                cParams = ZSTD_adjustCParams(cParams, 0, 0);
+
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_windowLog, cParams.windowLog) );
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_hashLog, cParams.hashLog) );
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_chainLog, cParams.chainLog) );
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_searchLog, cParams.searchLog) );
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_minMatch, cParams.searchLength) );
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_targetLength, cParams.targetLength) );
+
+                /* unconditionally set, to be sync with decoder */
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_refDictContent, FUZ_rand(&lseed) & 1) );
+                if (FUZ_rand(&lseed) & 1) {
+                    CHECK_Z( ZSTD_CCtx_loadDictionary(zc, dict, dictSize) );
+                    if (dict && dictSize) {
+                        /* test that compression parameters are rejected (correctly) after loading a non-NULL dictionary */
+                        size_t const setError = ZSTD_CCtx_setParameter(zc, ZSTD_p_windowLog, cParams.windowLog-1) ;
+                        CHECK(!ZSTD_isError(setError), "ZSTD_CCtx_setParameter should have failed");
+                }   } else {
+                    CHECK_Z( ZSTD_CCtx_refPrefix(zc, dict, dictSize) );
+                }
+
+                /* mess with frame parameters */
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_checksumFlag, FUZ_rand(&lseed) & 1) );
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_dictIDFlag, FUZ_rand(&lseed) & 1) );
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_contentSizeFlag, FUZ_rand(&lseed) & 1) );
+                if (FUZ_rand(&lseed) & 1) CHECK_Z( ZSTD_CCtx_setPledgedSrcSize(zc, pledgedSrcSize) );
+                DISPLAYLEVEL(5, "pledgedSrcSize : %u \n", (U32)pledgedSrcSize);
+
+                /* multi-threading parameters */
+                {   U32 const nbThreadsCandidate = (FUZ_rand(&lseed) & 4) + 1;
+                    U32 const nbThreads = MIN(nbThreadsCandidate, nbThreadsMax);
+                    CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_nbThreads, nbThreads) );
+                    if (nbThreads > 1) {
+                        U32 const jobLog = FUZ_rand(&lseed) % (testLog+1);
+                        CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_overlapSizeLog, FUZ_rand(&lseed) % 10) );
+                        CHECK_Z( ZSTD_CCtx_setParameter(zc, ZSTD_p_jobSize, (U32)FUZ_rLogLength(&lseed, jobLog)) );
+        }   }   }   }
+
+        /* multi-segments compression test */
+        XXH64_reset(&xxhState, 0);
+        {   ZSTD_outBuffer outBuff = { cBuffer, cBufferSize, 0 } ;
+            U32 n;
+            for (n=0, cSize=0, totalTestSize=0 ; totalTestSize < maxTestSize ; n++) {
+                /* compress random chunks into randomly sized dst buffers */
+                size_t const randomSrcSize = FUZ_randomLength(&lseed, maxSampleLog);
+                size_t const srcSize = MIN(maxTestSize-totalTestSize, randomSrcSize);
+                size_t const srcStart = FUZ_rand(&lseed) % (srcBufferSize - srcSize);
+                size_t const randomDstSize = FUZ_randomLength(&lseed, maxSampleLog);
+                size_t const dstBuffSize = MIN(cBufferSize - cSize, randomDstSize);
+                ZSTD_EndDirective const flush = (FUZ_rand(&lseed) & 15) ? ZSTD_e_continue : ZSTD_e_flush;
+                ZSTD_inBuffer inBuff = { srcBuffer+srcStart, srcSize, 0 };
+                outBuff.size = outBuff.pos + dstBuffSize;
+
+                CHECK_Z( ZSTD_compress_generic(zc, &outBuff, &inBuff, flush) );
+                DISPLAYLEVEL(5, "compress consumed %u bytes (total : %u) \n",
+                    (U32)inBuff.pos, (U32)(totalTestSize + inBuff.pos));
+
+                XXH64_update(&xxhState, srcBuffer+srcStart, inBuff.pos);
+                memcpy(copyBuffer+totalTestSize, srcBuffer+srcStart, inBuff.pos);
+                totalTestSize += inBuff.pos;
+            }
+
+            /* final frame epilogue */
+            {   size_t remainingToFlush = (size_t)(-1);
+                while (remainingToFlush) {
+                    ZSTD_inBuffer inBuff = { NULL, 0, 0 };
+                    size_t const randomDstSize = FUZ_randomLength(&lseed, maxSampleLog);
+                    size_t const adjustedDstSize = MIN(cBufferSize - cSize, randomDstSize);
+                    outBuff.size = outBuff.pos + adjustedDstSize;
+                    DISPLAYLEVEL(5, "End-flush into dst buffer of size %u \n", (U32)adjustedDstSize);
+                    remainingToFlush = ZSTD_compress_generic(zc, &outBuff, &inBuff, ZSTD_e_end);
+                    CHECK(ZSTD_isError(remainingToFlush),
+                        "ZSTD_compress_generic w/ ZSTD_e_end error : %s",
+                        ZSTD_getErrorName(remainingToFlush) );
+            }   }
+            crcOrig = XXH64_digest(&xxhState);
+            cSize = outBuff.pos;
+            DISPLAYLEVEL(5, "Frame completed : %u bytes \n", (U32)cSize);
+        }
+
+        /* multi - fragments decompression test */
+        if (!dictSize /* don't reset if dictionary : could be different */ && (FUZ_rand(&lseed) & 1)) {
+            DISPLAYLEVEL(5, "resetting DCtx (dict:%08X) \n", (U32)(size_t)dict);
+            CHECK_Z( ZSTD_resetDStream(zd) );
+        } else {
+            DISPLAYLEVEL(5, "using dict of size %u \n", (U32)dictSize);
+            CHECK_Z( ZSTD_initDStream_usingDict(zd, dict, dictSize) );
+        }
+        {   size_t decompressionResult = 1;
+            ZSTD_inBuffer  inBuff = { cBuffer, cSize, 0 };
+            ZSTD_outBuffer outBuff= { dstBuffer, dstBufferSize, 0 };
+            for (totalGenSize = 0 ; decompressionResult ; ) {
+                size_t const readCSrcSize = FUZ_randomLength(&lseed, maxSampleLog);
+                size_t const randomDstSize = FUZ_randomLength(&lseed, maxSampleLog);
+                size_t const dstBuffSize = MIN(dstBufferSize - totalGenSize, randomDstSize);
+                inBuff.size = inBuff.pos + readCSrcSize;
+                outBuff.size = inBuff.pos + dstBuffSize;
+                DISPLAYLEVEL(5, "ZSTD_decompressStream input %u bytes (pos:%u/%u)\n",
+                            (U32)readCSrcSize, (U32)inBuff.pos, (U32)cSize);
+                decompressionResult = ZSTD_decompressStream(zd, &outBuff, &inBuff);
+                CHECK (ZSTD_isError(decompressionResult), "decompression error : %s", ZSTD_getErrorName(decompressionResult));
+                DISPLAYLEVEL(5, "inBuff.pos = %u \n", (U32)readCSrcSize);
+            }
+            CHECK (outBuff.pos != totalTestSize, "decompressed data : wrong size (%u != %u)", (U32)outBuff.pos, (U32)totalTestSize);
+            CHECK (inBuff.pos != cSize, "compressed data should be fully read (%u != %u)", (U32)inBuff.pos, (U32)cSize);
+            {   U64 const crcDest = XXH64(dstBuffer, totalTestSize, 0);
+                if (crcDest!=crcOrig) findDiff(copyBuffer, dstBuffer, totalTestSize);
+                CHECK (crcDest!=crcOrig, "decompressed data corrupted");
+        }   }
+
+        /*=====   noisy/erroneous src decompression test   =====*/
+
+        /* add some noise */
+        {   U32 const nbNoiseChunks = (FUZ_rand(&lseed) & 7) + 2;
+            U32 nn; for (nn=0; nn<nbNoiseChunks; nn++) {
+                size_t const randomNoiseSize = FUZ_randomLength(&lseed, maxSampleLog);
+                size_t const noiseSize  = MIN((cSize/3) , randomNoiseSize);
+                size_t const noiseStart = FUZ_rand(&lseed) % (srcBufferSize - noiseSize);
+                size_t const cStart = FUZ_rand(&lseed) % (cSize - noiseSize);
+                memcpy(cBuffer+cStart, srcBuffer+noiseStart, noiseSize);
+        }   }
+
+        /* try decompression on noisy data */
+        CHECK_Z( ZSTD_initDStream(zd_noise) );   /* note : no dictionary */
+        {   ZSTD_inBuffer  inBuff = { cBuffer, cSize, 0 };
+            ZSTD_outBuffer outBuff= { dstBuffer, dstBufferSize, 0 };
+            while (outBuff.pos < dstBufferSize) {
+                size_t const randomCSrcSize = FUZ_randomLength(&lseed, maxSampleLog);
+                size_t const randomDstSize = FUZ_randomLength(&lseed, maxSampleLog);
+                size_t const adjustedDstSize = MIN(dstBufferSize - outBuff.pos, randomDstSize);
+                size_t const adjustedCSrcSize = MIN(cSize - inBuff.pos, randomCSrcSize);
+                outBuff.size = outBuff.pos + adjustedDstSize;
+                inBuff.size  = inBuff.pos + adjustedCSrcSize;
+                {   size_t const decompressError = ZSTD_decompressStream(zd, &outBuff, &inBuff);
+                    if (ZSTD_isError(decompressError)) break;   /* error correctly detected */
+                    /* Good so far, but no more progress possible */
+                    if (outBuff.pos < outBuff.size && inBuff.pos == cSize) break;
+    }   }   }   }
+    DISPLAY("\r%u fuzzer tests completed   \n", testNb-1);
+
+_cleanup:
+    ZSTD_freeCCtx(zc);
+    ZSTD_freeDStream(zd);
+    ZSTD_freeDStream(zd_noise);
+    free(cNoiseBuffer[0]);
+    free(cNoiseBuffer[1]);
+    free(cNoiseBuffer[2]);
+    free(cNoiseBuffer[3]);
+    free(cNoiseBuffer[4]);
+    free(copyBuffer);
+    free(cBuffer);
+    free(dstBuffer);
+    return result;
+
+_output_error:
+    result = 1;
+    goto _cleanup;
+}
+
+
 /*-*******************************************************
 *  Command line
 *********************************************************/
@@ -1129,6 +1528,7 @@ int FUZ_usage(const char* programName)
     return 0;
 }
 
+typedef enum { simple_api, mt_api, advanced_api } e_api;
 
 int main(int argc, const char** argv)
 {
@@ -1140,11 +1540,11 @@ int main(int argc, const char** argv)
     int proba = FUZ_COMPRESSIBILITY_DEFAULT;
     int result=0;
     int mainPause = 0;
-    int mtOnly = 0;
-    int bigTests = 1;
+    int bigTests = (sizeof(size_t) == 8);
+    e_api selected_api = simple_api;
     const char* const programName = argv[0];
     ZSTD_customMem const customMem = { allocFunction, freeFunction, NULL };
-    ZSTD_customMem const customNULL = { NULL, NULL, NULL };
+    ZSTD_customMem const customNULL = ZSTD_defaultCMem;
 
     /* Check command line */
     for(argNb=1; argNb<argc; argNb++) {
@@ -1154,7 +1554,8 @@ int main(int argc, const char** argv)
         /* Parsing commands. Aggregated commands are allowed */
         if (argument[0]=='-') {
 
-            if (!strcmp(argument, "--mt")) { mtOnly=1; continue; }
+            if (!strcmp(argument, "--mt")) { selected_api=mt_api; continue; }
+            if (!strcmp(argument, "--newapi")) { selected_api=advanced_api; continue; }
             if (!strcmp(argument, "--no-big-tests")) { bigTests=0; continue; }
 
             argument++;
@@ -1261,8 +1662,22 @@ int main(int argc, const char** argv)
             result = basicUnitTests(0, ((double)proba) / 100, customMem);  /* use custom memory allocation functions */
     }   }
 
-    if (!result && !mtOnly) result = fuzzerTests(seed, nbTests, testNb, ((double)proba) / 100, bigTests);
-    if (!result) result = fuzzerTests_MT(seed, nbTests, testNb, ((double)proba) / 100, bigTests);
+    if (!result) {
+        switch(selected_api)
+        {
+        case simple_api :
+            result = fuzzerTests(seed, nbTests, testNb, ((double)proba) / 100, bigTests);
+            break;
+        case mt_api :
+            result = fuzzerTests_MT(seed, nbTests, testNb, ((double)proba) / 100, bigTests);
+            break;
+        case advanced_api :
+            result = fuzzerTests_newAPI(seed, nbTests, testNb, ((double)proba) / 100, bigTests);
+            break;
+        default :
+            assert(0);   /* impossible */
+        }
+    }
 
     if (mainPause) {
         int unused;
diff --git a/zlibWrapper/Makefile b/zlibWrapper/Makefile
index 5a6378767bbe..4e8fb4a329b6 100644
--- a/zlibWrapper/Makefile
+++ b/zlibWrapper/Makefile
@@ -18,9 +18,12 @@ EXAMPLE_PATH = examples
 PROGRAMS_PATH = ../programs
 TEST_FILE = ../doc/zstd_compression_format.md
 
-CPPFLAGS = -DXXH_NAMESPACE=ZSTD_ -I$(ZLIB_PATH) -I$(PROGRAMS_PATH) -I$(ZSTDLIBDIR) -I$(ZSTDLIBDIR)/common -I$(ZLIBWRAPPER_PATH)
+CPPFLAGS = -DXXH_NAMESPACE=ZSTD_ -I$(ZLIB_PATH) -I$(PROGRAMS_PATH)       \
+           -I$(ZSTDLIBDIR) -I$(ZSTDLIBDIR)/common -I$(ZLIBWRAPPER_PATH)
 CFLAGS  ?= $(MOREFLAGS) -O3 -std=gnu99
-CFLAGS  += -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow -Wswitch-enum -Wdeclaration-after-statement -Wstrict-prototypes -Wundef -Wstrict-aliasing=1
+CFLAGS  += -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow -Wswitch-enum \
+           -Wdeclaration-after-statement -Wstrict-prototypes -Wundef     \
+           -Wstrict-aliasing=1
 
 
 # Define *.exe as extension for Windows systems
@@ -48,8 +51,8 @@ test: example fitblk example_zstd fitblk_zstd zwrapbench minigzip minigzip_zstd
 	#cp example$(EXT).gz example$(EXT)_gz.gz
 	./minigzip_zstd -d example$(EXT).gz
 	@echo ---- minigzip end ----
-	./zwrapbench -qb3B1K $(TEST_FILE)
-	./zwrapbench -rqb1e5 ../lib ../programs ../tests
+	./zwrapbench -qi1b3B1K $(TEST_FILE)
+	./zwrapbench -rqi1b1e5 ../lib ../programs ../tests
 
 #valgrindTest: ZSTDLIBRARY = $(ZSTDLIBDIR)/libzstd.so
 valgrindTest: VALGRIND = LD_LIBRARY_PATH=$(ZSTDLIBDIR) valgrind --track-origins=yes --leak-check=full --error-exitcode=1
@@ -61,8 +64,8 @@ valgrindTest: clean example fitblk example_zstd fitblk_zstd zwrapbench
 	$(VALGRIND) ./fitblk 40960 <$(TEST_FILE)
 	$(VALGRIND) ./fitblk_zstd 10240 <$(TEST_FILE)
 	$(VALGRIND) ./fitblk_zstd 40960 <$(TEST_FILE)
-	$(VALGRIND) ./zwrapbench -qb3B1K $(TEST_FILE)
-	$(VALGRIND) ./zwrapbench -rqb1e5 ../lib ../programs ../tests
+	$(VALGRIND) ./zwrapbench -qi1b3B1K $(TEST_FILE)
+	$(VALGRIND) ./zwrapbench -rqi1b1e5 ../lib ../programs ../tests
 
 #.c.o:
 #	$(CC) $(CFLAGS) $(CPPFLAGS) -c -o $@ $<
diff --git a/zlibWrapper/examples/zwrapbench.c b/zlibWrapper/examples/zwrapbench.c
index a57ed51ec141..1fc2117f69a7 100644
--- a/zlibWrapper/examples/zwrapbench.c
+++ b/zlibWrapper/examples/zwrapbench.c
@@ -90,7 +90,7 @@ static clock_t g_time = 0;
 #ifndef DEBUG
 #  define DEBUG 0
 #endif
-#define DEBUGOUTPUT(...) if (DEBUG) DISPLAY(__VA_ARGS__);
+#define DEBUGOUTPUT(...) { if (DEBUG) DISPLAY(__VA_ARGS__); }
 #define EXM_THROW(error, ...)                                             \
 {                                                                         \
     DEBUGOUTPUT("Error defined at %s, line %i : \n", __FILE__, __LINE__); \
@@ -236,7 +236,7 @@ static int BMK_benchMem(z_const void* srcBuffer, size_t srcSize,
                 if (compressor == BMK_ZSTD) {
                     ZSTD_parameters const zparams = ZSTD_getParams(cLevel, avgSize, dictBufferSize);
                     ZSTD_customMem const cmem = { NULL, NULL, NULL };
-                    ZSTD_CDict* const cdict = ZSTD_createCDict_advanced(dictBuffer, dictBufferSize, 1, zparams.cParams, cmem);
+                    ZSTD_CDict* const cdict = ZSTD_createCDict_advanced(dictBuffer, dictBufferSize, 1 /*byRef*/, ZSTD_dm_auto, zparams.cParams, cmem);
                     if (cdict==NULL) EXM_THROW(1, "ZSTD_createCDict_advanced() allocation failure");
 
                     do {
diff --git a/zlibWrapper/zstd_zlibwrapper.c b/zlibWrapper/zstd_zlibwrapper.c
index 1960d19e970c..ade3b88cd1f4 100644
--- a/zlibWrapper/zstd_zlibwrapper.c
+++ b/zlibWrapper/zstd_zlibwrapper.c
@@ -8,35 +8,42 @@
  */
 
 
+/* ===   Tuning parameters   === */
+#ifndef ZWRAP_USE_ZSTD
+    #define ZWRAP_USE_ZSTD 0
+#endif
+
+
+/* ===   Dependencies   === */
+#include <stdlib.h>
 #include <stdio.h>                 /* vsprintf */
 #include <stdarg.h>                /* va_list, for z_gzprintf */
 #define NO_DUMMY_DECL
 #define ZLIB_CONST
 #include <zlib.h>                  /* without #define Z_PREFIX */
 #include "zstd_zlibwrapper.h"
-#define ZSTD_STATIC_LINKING_ONLY   /* ZSTD_MAGICNUMBER */
+#define ZSTD_STATIC_LINKING_ONLY   /* ZSTD_isFrame, ZSTD_MAGICNUMBER */
 #include "zstd.h"
-#include "zstd_internal.h"         /* defaultCustomMem */
+#include "zstd_internal.h"         /* ZSTD_malloc, ZSTD_free */
 
 
+/* ===   Constants   === */
 #define Z_INFLATE_SYNC              8
 #define ZLIB_HEADERSIZE             4
 #define ZSTD_HEADERSIZE             ZSTD_frameHeaderSize_min
 #define ZWRAP_DEFAULT_CLEVEL        3   /* Z_DEFAULT_COMPRESSION is translated to ZWRAP_DEFAULT_CLEVEL for zstd */
 
-#define LOG_WRAPPERC(...)  /* printf(__VA_ARGS__) */
-#define LOG_WRAPPERD(...)  /* printf(__VA_ARGS__) */
+
+/* ===   Debug   === */
+#define LOG_WRAPPERC(...)  /* fprintf(stderr, __VA_ARGS__) */
+#define LOG_WRAPPERD(...)  /* fprintf(stderr, __VA_ARGS__) */
 
 #define FINISH_WITH_GZ_ERR(msg) { (void)msg; return Z_STREAM_ERROR; }
 #define FINISH_WITH_NULL_ERR(msg) { (void)msg; return NULL; }
 
 
-
-#ifndef ZWRAP_USE_ZSTD
-    #define ZWRAP_USE_ZSTD 0
-#endif
-
-static int g_ZWRAP_useZSTDcompression = ZWRAP_USE_ZSTD;   /* 0 = don't use ZSTD */
+/* ===   Wrapper   === */
+static int g_ZWRAP_useZSTDcompression = ZWRAP_USE_ZSTD; /* 0 = don't use ZSTD */
 
 void ZWRAP_useZSTDcompression(int turn_on) { g_ZWRAP_useZSTDcompression = turn_on; }
 
@@ -62,7 +69,7 @@ static void* ZWRAP_allocFunction(void* opaque, size_t size)
 {
     z_streamp strm = (z_streamp) opaque;
     void* address = strm->zalloc(strm->opaque, 1, (uInt)size);
-  /*  printf("ZWRAP alloc %p, %d \n", address, (int)size); */
+    /* LOG_WRAPPERC("ZWRAP alloc %p, %d \n", address, (int)size); */
     return address;
 }
 
@@ -70,12 +77,12 @@ static void ZWRAP_freeFunction(void* opaque, void* address)
 {
     z_streamp strm = (z_streamp) opaque;
     strm->zfree(strm->opaque, address);
-   /* if (address) printf("ZWRAP free %p \n", address); */
+   /* if (address) LOG_WRAPPERC("ZWRAP free %p \n", address); */
 }
 
 
 
-/* *** Compression *** */
+/* ===   Compression   === */
 typedef enum { ZWRAP_useInit, ZWRAP_useReset, ZWRAP_streamEnd } ZWRAP_state_t;
 
 typedef struct {
@@ -95,16 +102,16 @@ typedef ZWRAP_CCtx internal_state;
 
 
 
-size_t ZWRAP_freeCCtx(ZWRAP_CCtx* zwc)
+static size_t ZWRAP_freeCCtx(ZWRAP_CCtx* zwc)
 {
     if (zwc==NULL) return 0;   /* support free on NULL */
-    if (zwc->zbc) ZSTD_freeCStream(zwc->zbc);
-    zwc->customMem.customFree(zwc->customMem.opaque, zwc);
+    ZSTD_freeCStream(zwc->zbc);
+    ZSTD_free(zwc, zwc->customMem);
     return 0;
 }
 
 
-ZWRAP_CCtx* ZWRAP_createCCtx(z_streamp strm)
+static ZWRAP_CCtx* ZWRAP_createCCtx(z_streamp strm)
 {
     ZWRAP_CCtx* zwc;
 
@@ -113,37 +120,36 @@ ZWRAP_CCtx* ZWRAP_createCCtx(z_streamp strm)
         if (zwc==NULL) return NULL;
         memset(zwc, 0, sizeof(ZWRAP_CCtx));
         memcpy(&zwc->allocFunc, strm, sizeof(z_stream));
-        { ZSTD_customMem ZWRAP_customMem = { ZWRAP_allocFunction, ZWRAP_freeFunction, &zwc->allocFunc };
-          memcpy(&zwc->customMem, &ZWRAP_customMem, sizeof(ZSTD_customMem));
-        }
+        { ZSTD_customMem const ZWRAP_customMem = { ZWRAP_allocFunction, ZWRAP_freeFunction, &zwc->allocFunc };
+          zwc->customMem = ZWRAP_customMem; }
     } else {
-        zwc = (ZWRAP_CCtx*)defaultCustomMem.customAlloc(defaultCustomMem.opaque, sizeof(ZWRAP_CCtx));
+        zwc = (ZWRAP_CCtx*)calloc(1, sizeof(*zwc));
         if (zwc==NULL) return NULL;
-        memset(zwc, 0, sizeof(ZWRAP_CCtx));
-        memcpy(&zwc->customMem, &defaultCustomMem, sizeof(ZSTD_customMem));
     }
 
     return zwc;
 }
 
 
-int ZWRAP_initializeCStream(ZWRAP_CCtx* zwc, const void* dict, size_t dictSize, unsigned long long pledgedSrcSize)
+static int ZWRAP_initializeCStream(ZWRAP_CCtx* zwc, const void* dict, size_t dictSize, unsigned long long pledgedSrcSize)
 {
     LOG_WRAPPERC("- ZWRAP_initializeCStream=%p\n", zwc);
     if (zwc == NULL || zwc->zbc == NULL) return Z_STREAM_ERROR;
 
     if (!pledgedSrcSize) pledgedSrcSize = zwc->pledgedSrcSize;
-    { ZSTD_parameters const params = ZSTD_getParams(zwc->compressionLevel, pledgedSrcSize, dictSize);
-      size_t errorCode;
-      LOG_WRAPPERC("pledgedSrcSize=%d windowLog=%d chainLog=%d hashLog=%d searchLog=%d searchLength=%d strategy=%d\n", (int)pledgedSrcSize, params.cParams.windowLog, params.cParams.chainLog, params.cParams.hashLog, params.cParams.searchLog, params.cParams.searchLength, params.cParams.strategy);
-      errorCode = ZSTD_initCStream_advanced(zwc->zbc, dict, dictSize, params, pledgedSrcSize);
-      if (ZSTD_isError(errorCode)) return Z_STREAM_ERROR; }
+    {   ZSTD_parameters const params = ZSTD_getParams(zwc->compressionLevel, pledgedSrcSize, dictSize);
+        size_t initErr;
+        LOG_WRAPPERC("pledgedSrcSize=%d windowLog=%d chainLog=%d hashLog=%d searchLog=%d searchLength=%d strategy=%d\n",
+                    (int)pledgedSrcSize, params.cParams.windowLog, params.cParams.chainLog, params.cParams.hashLog, params.cParams.searchLog, params.cParams.searchLength, params.cParams.strategy);
+        initErr = ZSTD_initCStream_advanced(zwc->zbc, dict, dictSize, params, pledgedSrcSize);
+        if (ZSTD_isError(initErr)) return Z_STREAM_ERROR;
+    }
 
     return Z_OK;
 }
 
 
-int ZWRAPC_finishWithError(ZWRAP_CCtx* zwc, z_streamp strm, int error)
+static int ZWRAPC_finishWithError(ZWRAP_CCtx* zwc, z_streamp strm, int error)
 {
     LOG_WRAPPERC("- ZWRAPC_finishWithError=%d\n", error);
     if (zwc) ZWRAP_freeCCtx(zwc);
@@ -152,7 +158,7 @@ int ZWRAPC_finishWithError(ZWRAP_CCtx* zwc, z_streamp strm, int error)
 }
 
 
-int ZWRAPC_finishWithErrorMsg(z_streamp strm, char* message)
+static int ZWRAPC_finishWithErrorMsg(z_streamp strm, char* message)
 {
     ZWRAP_CCtx* zwc = (ZWRAP_CCtx*) strm->state;
     strm->msg = message;
@@ -219,7 +225,7 @@ int ZWRAP_deflateReset_keepDict(z_streamp strm)
         return deflateReset(strm);
 
     { ZWRAP_CCtx* zwc = (ZWRAP_CCtx*) strm->state;
-      if (zwc) { 
+      if (zwc) {
           zwc->streamEnd = 0;
           zwc->totalInBytes = 0;
       }
@@ -277,34 +283,36 @@ ZEXTERN int ZEXPORT z_deflate OF((z_streamp strm, int flush))
     ZWRAP_CCtx* zwc;
 
     if (!g_ZWRAP_useZSTDcompression) {
-        int res;
-        LOG_WRAPPERC("- deflate1 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d\n", (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out);
-        res = deflate(strm, flush);
-        return res;
+        LOG_WRAPPERC("- deflate1 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d\n",
+                    (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out);
+        return deflate(strm, flush);
     }
 
     zwc = (ZWRAP_CCtx*) strm->state;
     if (zwc == NULL) { LOG_WRAPPERC("zwc == NULL\n"); return Z_STREAM_ERROR; }
 
     if (zwc->zbc == NULL) {
-        int res;
         zwc->zbc = ZSTD_createCStream_advanced(zwc->customMem);
         if (zwc->zbc == NULL) return ZWRAPC_finishWithError(zwc, strm, 0);
-        res = ZWRAP_initializeCStream(zwc, NULL, 0, (flush == Z_FINISH) ? strm->avail_in : 0);
-        if (res != Z_OK) return ZWRAPC_finishWithError(zwc, strm, res);
+        { int const initErr = ZWRAP_initializeCStream(zwc, NULL, 0, (flush == Z_FINISH) ? strm->avail_in : 0);
+          if (initErr != Z_OK) return ZWRAPC_finishWithError(zwc, strm, initErr); }
         if (flush != Z_FINISH) zwc->comprState = ZWRAP_useReset;
     } else {
         if (zwc->totalInBytes == 0) {
             if (zwc->comprState == ZWRAP_useReset) {
-                size_t const errorCode = ZSTD_resetCStream(zwc->zbc, (flush == Z_FINISH) ? strm->avail_in : zwc->pledgedSrcSize);
-                if (ZSTD_isError(errorCode)) { LOG_WRAPPERC("ERROR: ZSTD_resetCStream errorCode=%s\n", ZSTD_getErrorName(errorCode)); return ZWRAPC_finishWithError(zwc, strm, 0); }
+                size_t const resetErr = ZSTD_resetCStream(zwc->zbc, (flush == Z_FINISH) ? strm->avail_in : zwc->pledgedSrcSize);
+                if (ZSTD_isError(resetErr)) {
+                    LOG_WRAPPERC("ERROR: ZSTD_resetCStream errorCode=%s\n",
+                                ZSTD_getErrorName(resetErr));
+                    return ZWRAPC_finishWithError(zwc, strm, 0);
+                }
             } else {
-                int res = ZWRAP_initializeCStream(zwc, NULL, 0, (flush == Z_FINISH) ? strm->avail_in : 0);
+                int const res = ZWRAP_initializeCStream(zwc, NULL, 0, (flush == Z_FINISH) ? strm->avail_in : 0);
                 if (res != Z_OK) return ZWRAPC_finishWithError(zwc, strm, res);
                 if (flush != Z_FINISH) zwc->comprState = ZWRAP_useReset;
             }
-        }
-    }
+        }  /* (zwc->totalInBytes == 0) */
+    }  /* ! (zwc->zbc == NULL) */
 
     LOG_WRAPPERC("- deflate2 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d\n", (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out);
     if (strm->avail_in > 0) {
@@ -314,9 +322,9 @@ ZEXTERN int ZEXPORT z_deflate OF((z_streamp strm, int flush))
         zwc->outBuffer.dst = strm->next_out;
         zwc->outBuffer.size = strm->avail_out;
         zwc->outBuffer.pos = 0;
-        { size_t const errorCode = ZSTD_compressStream(zwc->zbc, &zwc->outBuffer, &zwc->inBuffer);
+        { size_t const cErr = ZSTD_compressStream(zwc->zbc, &zwc->outBuffer, &zwc->inBuffer);
           LOG_WRAPPERC("deflate ZSTD_compressStream srcSize=%d dstCapacity=%d\n", (int)zwc->inBuffer.size, (int)zwc->outBuffer.size);
-          if (ZSTD_isError(errorCode)) return ZWRAPC_finishWithError(zwc, strm, 0);
+          if (ZSTD_isError(cErr)) return ZWRAPC_finishWithError(zwc, strm, 0);
         }
         strm->next_out += zwc->outBuffer.pos;
         strm->total_out += zwc->outBuffer.pos;
@@ -346,8 +354,12 @@ ZEXTERN int ZEXPORT z_deflate OF((z_streamp strm, int flush))
         strm->next_out += zwc->outBuffer.pos;
         strm->total_out += zwc->outBuffer.pos;
         strm->avail_out -= zwc->outBuffer.pos;
-        if (bytesLeft == 0) { zwc->streamEnd = 1; LOG_WRAPPERC("Z_STREAM_END2 strm->total_in=%d strm->avail_out=%d strm->total_out=%d\n", (int)strm->total_in, (int)strm->avail_out, (int)strm->total_out); return Z_STREAM_END; }
-    }
+        if (bytesLeft == 0) {
+            zwc->streamEnd = 1;
+            LOG_WRAPPERC("Z_STREAM_END2 strm->total_in=%d strm->avail_out=%d strm->total_out=%d\n",
+                        (int)strm->total_in, (int)strm->avail_out, (int)strm->total_out);
+            return Z_STREAM_END;
+    }   }
     else
     if (flush == Z_SYNC_FLUSH || flush == Z_PARTIAL_FLUSH) {
         size_t bytesLeft;
@@ -410,12 +422,13 @@ ZEXTERN int ZEXPORT z_deflateParams OF((z_streamp strm,
 
 
 
-/* *** Decompression *** */
+/* ===   Decompression   === */
+
 typedef enum { ZWRAP_ZLIB_STREAM, ZWRAP_ZSTD_STREAM, ZWRAP_UNKNOWN_STREAM } ZWRAP_stream_type;
 
 typedef struct {
     ZSTD_DStream* zbd;
-    char headerBuf[16]; /* should be equal or bigger than ZSTD_frameHeaderSize_min */
+    char headerBuf[16];   /* must be >= ZSTD_frameHeaderSize_min */
     int errorCount;
     unsigned long long totalInBytes; /* we need it as strm->total_in can be reset by user */
     ZWRAP_state_t decompState;
@@ -427,72 +440,66 @@ typedef struct {
     char *version;
     int windowBits;
     ZSTD_customMem customMem;
-    z_stream allocFunc; /* copy of zalloc, zfree, opaque */
+    z_stream allocFunc; /* just to copy zalloc, zfree, opaque */
 } ZWRAP_DCtx;
 
 
-int ZWRAP_isUsingZSTDdecompression(z_streamp strm)
-{
-    if (strm == NULL) return 0;
-    return (strm->reserved == ZWRAP_ZSTD_STREAM);
-}
-
-
-void ZWRAP_initDCtx(ZWRAP_DCtx* zwd)
+static void ZWRAP_initDCtx(ZWRAP_DCtx* zwd)
 {
     zwd->errorCount = 0;
     zwd->outBuffer.pos = 0;
     zwd->outBuffer.size = 0;
 }
 
-
-ZWRAP_DCtx* ZWRAP_createDCtx(z_streamp strm)
+static ZWRAP_DCtx* ZWRAP_createDCtx(z_streamp strm)
 {
     ZWRAP_DCtx* zwd;
+    MEM_STATIC_ASSERT(sizeof(zwd->headerBuf) >= ZSTD_FRAMEHEADERSIZE_MIN);   /* check static buffer size condition */
 
     if (strm->zalloc && strm->zfree) {
         zwd = (ZWRAP_DCtx*)strm->zalloc(strm->opaque, 1, sizeof(ZWRAP_DCtx));
         if (zwd==NULL) return NULL;
         memset(zwd, 0, sizeof(ZWRAP_DCtx));
-        memcpy(&zwd->allocFunc, strm, sizeof(z_stream));
-        { ZSTD_customMem ZWRAP_customMem = { ZWRAP_allocFunction, ZWRAP_freeFunction, &zwd->allocFunc };
-          memcpy(&zwd->customMem, &ZWRAP_customMem, sizeof(ZSTD_customMem));
-        }
+        zwd->allocFunc = *strm;  /* just to copy zalloc, zfree & opaque */
+        { ZSTD_customMem const ZWRAP_customMem = { ZWRAP_allocFunction, ZWRAP_freeFunction, &zwd->allocFunc };
+          zwd->customMem = ZWRAP_customMem; }
     } else {
-        zwd = (ZWRAP_DCtx*)defaultCustomMem.customAlloc(defaultCustomMem.opaque, sizeof(ZWRAP_DCtx));
+        zwd = (ZWRAP_DCtx*)calloc(1, sizeof(*zwd));
         if (zwd==NULL) return NULL;
-        memset(zwd, 0, sizeof(ZWRAP_DCtx));
-        memcpy(&zwd->customMem, &defaultCustomMem, sizeof(ZSTD_customMem));
     }
 
-    MEM_STATIC_ASSERT(sizeof(zwd->headerBuf) >= ZSTD_FRAMEHEADERSIZE_MIN);   /* if compilation fails here, assertion is false */
     ZWRAP_initDCtx(zwd);
     return zwd;
 }
 
-
-size_t ZWRAP_freeDCtx(ZWRAP_DCtx* zwd)
+static size_t ZWRAP_freeDCtx(ZWRAP_DCtx* zwd)
 {
     if (zwd==NULL) return 0;   /* support free on null */
-    if (zwd->zbd) ZSTD_freeDStream(zwd->zbd);
-    if (zwd->version) zwd->customMem.customFree(zwd->customMem.opaque, zwd->version);
-    zwd->customMem.customFree(zwd->customMem.opaque, zwd);
+    ZSTD_freeDStream(zwd->zbd);
+    ZSTD_free(zwd->version, zwd->customMem);
+    ZSTD_free(zwd, zwd->customMem);
     return 0;
 }
 
 
-int ZWRAPD_finishWithError(ZWRAP_DCtx* zwd, z_streamp strm, int error)
+int ZWRAP_isUsingZSTDdecompression(z_streamp strm)
+{
+    if (strm == NULL) return 0;
+    return (strm->reserved == ZWRAP_ZSTD_STREAM);
+}
+
+
+static int ZWRAPD_finishWithError(ZWRAP_DCtx* zwd, z_streamp strm, int error)
 {
     LOG_WRAPPERD("- ZWRAPD_finishWithError=%d\n", error);
-    if (zwd) ZWRAP_freeDCtx(zwd);
-    if (strm) strm->state = NULL;
+    ZWRAP_freeDCtx(zwd);
+    strm->state = NULL;
     return (error) ? error : Z_STREAM_ERROR;
 }
 
-
-int ZWRAPD_finishWithErrorMsg(z_streamp strm, char* message)
+static int ZWRAPD_finishWithErrorMsg(z_streamp strm, char* message)
 {
-    ZWRAP_DCtx* zwd = (ZWRAP_DCtx*) strm->state;
+    ZWRAP_DCtx* const zwd = (ZWRAP_DCtx*) strm->state;
     strm->msg = message;
     if (zwd == NULL) return Z_STREAM_ERROR;
 
@@ -504,26 +511,25 @@ ZEXTERN int ZEXPORT z_inflateInit_ OF((z_streamp strm,
                                      const char *version, int stream_size))
 {
     if (g_ZWRAPdecompressionType == ZWRAP_FORCE_ZLIB) {
-        strm->reserved = ZWRAP_ZLIB_STREAM; /* mark as zlib stream */
+        strm->reserved = ZWRAP_ZLIB_STREAM;
         return inflateInit(strm);
     }
 
-    {
-    ZWRAP_DCtx* zwd = ZWRAP_createDCtx(strm);
-    LOG_WRAPPERD("- inflateInit\n");
-    if (zwd == NULL) return ZWRAPD_finishWithError(zwd, strm, 0);
+    {   ZWRAP_DCtx* const zwd = ZWRAP_createDCtx(strm);
+        LOG_WRAPPERD("- inflateInit\n");
+        if (zwd == NULL) return ZWRAPD_finishWithError(zwd, strm, 0);
 
-    zwd->version = zwd->customMem.customAlloc(zwd->customMem.opaque, strlen(version) + 1);
-    if (zwd->version == NULL) return ZWRAPD_finishWithError(zwd, strm, 0);
-    strcpy(zwd->version, version);
+        zwd->version = ZSTD_malloc(strlen(version)+1, zwd->customMem);
+        if (zwd->version == NULL) return ZWRAPD_finishWithError(zwd, strm, 0);
+        strcpy(zwd->version, version);
 
-    zwd->stream_size = stream_size;
-    zwd->totalInBytes = 0;
-    strm->state = (struct internal_state*) zwd; /* use state which in not used by user */
-    strm->total_in = 0;
-    strm->total_out = 0;
-    strm->reserved = ZWRAP_UNKNOWN_STREAM; /* mark as unknown steam */
-    strm->adler = 0;
+        zwd->stream_size = stream_size;
+        zwd->totalInBytes = 0;
+        strm->state = (struct internal_state*) zwd;
+        strm->total_in = 0;
+        strm->total_out = 0;
+        strm->reserved = ZWRAP_UNKNOWN_STREAM;
+        strm->adler = 0;
     }
 
     return Z_OK;
@@ -537,15 +543,14 @@ ZEXTERN int ZEXPORT z_inflateInit2_ OF((z_streamp strm, int  windowBits,
         return inflateInit2_(strm, windowBits, version, stream_size);
     }
 
-    {
-    int ret = z_inflateInit_ (strm, version, stream_size);
-    LOG_WRAPPERD("- inflateInit2 windowBits=%d\n", windowBits);
-    if (ret == Z_OK) {
-        ZWRAP_DCtx* zwd = (ZWRAP_DCtx*)strm->state;
-        if (zwd == NULL) return Z_STREAM_ERROR;
-        zwd->windowBits = windowBits;
-    }
-    return ret;
+    {   int const ret = z_inflateInit_ (strm, version, stream_size);
+        LOG_WRAPPERD("- inflateInit2 windowBits=%d\n", windowBits);
+        if (ret == Z_OK) {
+            ZWRAP_DCtx* const zwd = (ZWRAP_DCtx*)strm->state;
+            if (zwd == NULL) return Z_STREAM_ERROR;
+            zwd->windowBits = windowBits;
+        }
+        return ret;
     }
 }
 
@@ -555,7 +560,7 @@ int ZWRAP_inflateReset_keepDict(z_streamp strm)
     if (g_ZWRAPdecompressionType == ZWRAP_FORCE_ZLIB || !strm->reserved)
         return inflateReset(strm);
 
-    {   ZWRAP_DCtx* zwd = (ZWRAP_DCtx*) strm->state;
+    {   ZWRAP_DCtx* const zwd = (ZWRAP_DCtx*) strm->state;
         if (zwd == NULL) return Z_STREAM_ERROR;
         ZWRAP_initDCtx(zwd);
         zwd->decompState = ZWRAP_useReset;
@@ -574,10 +579,10 @@ ZEXTERN int ZEXPORT z_inflateReset OF((z_streamp strm))
     if (g_ZWRAPdecompressionType == ZWRAP_FORCE_ZLIB || !strm->reserved)
         return inflateReset(strm);
 
-    { int ret = ZWRAP_inflateReset_keepDict(strm);
+    { int const ret = ZWRAP_inflateReset_keepDict(strm);
       if (ret != Z_OK) return ret; }
 
-    { ZWRAP_DCtx* zwd = (ZWRAP_DCtx*) strm->state;
+    { ZWRAP_DCtx* const zwd = (ZWRAP_DCtx*) strm->state;
       if (zwd == NULL) return Z_STREAM_ERROR;
       zwd->decompState = ZWRAP_useInit; }
 
@@ -592,9 +597,9 @@ ZEXTERN int ZEXPORT z_inflateReset2 OF((z_streamp strm,
     if (g_ZWRAPdecompressionType == ZWRAP_FORCE_ZLIB || !strm->reserved)
         return inflateReset2(strm, windowBits);
 
-    {   int ret = z_inflateReset (strm);
+    {   int const ret = z_inflateReset (strm);
         if (ret == Z_OK) {
-            ZWRAP_DCtx* zwd = (ZWRAP_DCtx*)strm->state;
+            ZWRAP_DCtx* const zwd = (ZWRAP_DCtx*)strm->state;
             if (zwd == NULL) return Z_STREAM_ERROR;
             zwd->windowBits = windowBits;
         }
@@ -612,11 +617,10 @@ ZEXTERN int ZEXPORT z_inflateSetDictionary OF((z_streamp strm,
     if (g_ZWRAPdecompressionType == ZWRAP_FORCE_ZLIB || !strm->reserved)
         return inflateSetDictionary(strm, dictionary, dictLength);
 
-    {   size_t errorCode;
-        ZWRAP_DCtx* zwd = (ZWRAP_DCtx*) strm->state;
+    {   ZWRAP_DCtx* const zwd = (ZWRAP_DCtx*) strm->state;
         if (zwd == NULL || zwd->zbd == NULL) return Z_STREAM_ERROR;
-        errorCode = ZSTD_initDStream_usingDict(zwd->zbd, dictionary, dictLength);
-        if (ZSTD_isError(errorCode)) return ZWRAPD_finishWithError(zwd, strm, 0);
+        { size_t const initErr = ZSTD_initDStream_usingDict(zwd->zbd, dictionary, dictLength);
+          if (ZSTD_isError(initErr)) return ZWRAPD_finishWithError(zwd, strm, 0); }
         zwd->decompState = ZWRAP_useReset;
 
         if (zwd->totalInBytes == ZSTD_HEADERSIZE) {
@@ -626,14 +630,14 @@ ZEXTERN int ZEXPORT z_inflateSetDictionary OF((z_streamp strm,
             zwd->outBuffer.dst = strm->next_out;
             zwd->outBuffer.size = 0;
             zwd->outBuffer.pos = 0;
-            errorCode = ZSTD_decompressStream(zwd->zbd, &zwd->outBuffer, &zwd->inBuffer);
-            LOG_WRAPPERD("inflateSetDictionary ZSTD_decompressStream errorCode=%d srcSize=%d dstCapacity=%d\n", (int)errorCode, (int)zwd->inBuffer.size, (int)zwd->outBuffer.size);
-            if (zwd->inBuffer.pos < zwd->outBuffer.size || ZSTD_isError(errorCode)) {
-                LOG_WRAPPERD("ERROR: ZSTD_decompressStream %s\n", ZSTD_getErrorName(errorCode));
-                return ZWRAPD_finishWithError(zwd, strm, 0);
-            }
-        }
-    }
+            {   size_t const errorCode = ZSTD_decompressStream(zwd->zbd, &zwd->outBuffer, &zwd->inBuffer);
+                LOG_WRAPPERD("inflateSetDictionary ZSTD_decompressStream errorCode=%d srcSize=%d dstCapacity=%d\n",
+                             (int)errorCode, (int)zwd->inBuffer.size, (int)zwd->outBuffer.size);
+                if (zwd->inBuffer.pos < zwd->outBuffer.size || ZSTD_isError(errorCode)) {
+                    LOG_WRAPPERD("ERROR: ZSTD_decompressStream %s\n",
+                                 ZSTD_getErrorName(errorCode));
+                    return ZWRAPD_finishWithError(zwd, strm, 0);
+    }   }   }   }
 
     return Z_OK;
 }
@@ -642,156 +646,175 @@ ZEXTERN int ZEXPORT z_inflateSetDictionary OF((z_streamp strm,
 ZEXTERN int ZEXPORT z_inflate OF((z_streamp strm, int flush))
 {
     ZWRAP_DCtx* zwd;
-    int res;
+
     if (g_ZWRAPdecompressionType == ZWRAP_FORCE_ZLIB || !strm->reserved) {
-        LOG_WRAPPERD("- inflate1 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d\n", (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out);
-        res = inflate(strm, flush);
-        LOG_WRAPPERD("- inflate2 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d res=%d\n", (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out, res);
-        return res;
+        int const result = inflate(strm, flush);
+        LOG_WRAPPERD("- inflate2 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d res=%d\n",
+                     (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out, result);
+        return result;
     }
 
     if (strm->avail_in <= 0) return Z_OK;
 
-    {   size_t errorCode, srcSize;
-        zwd = (ZWRAP_DCtx*) strm->state;
-        LOG_WRAPPERD("- inflate1 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d\n", (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out);
+    zwd = (ZWRAP_DCtx*) strm->state;
+    LOG_WRAPPERD("- inflate1 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d\n",
+                 (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out);
 
-        if (zwd == NULL) return Z_STREAM_ERROR;
-        if (zwd->decompState == ZWRAP_streamEnd) return Z_STREAM_END;
-
-        if (zwd->totalInBytes < ZLIB_HEADERSIZE) {
-            if (zwd->totalInBytes == 0 && strm->avail_in >= ZLIB_HEADERSIZE) {
-                if (MEM_readLE32(strm->next_in) != ZSTD_MAGICNUMBER) {
-                    if (zwd->windowBits)
-                        errorCode = inflateInit2_(strm, zwd->windowBits, zwd->version, zwd->stream_size);
-                    else
-                        errorCode = inflateInit_(strm, zwd->version, zwd->stream_size);
-
-                    strm->reserved = ZWRAP_ZLIB_STREAM; /* mark as zlib stream */
-                    errorCode = ZWRAP_freeDCtx(zwd);
-                    if (ZSTD_isError(errorCode)) goto error;
-
-                    if (flush == Z_INFLATE_SYNC) res = inflateSync(strm);
-                    else res = inflate(strm, flush);
-                    LOG_WRAPPERD("- inflate3 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d res=%d\n", (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out, res);
-                    return res;
-                }
-            } else {
-                srcSize = MIN(strm->avail_in, ZLIB_HEADERSIZE - zwd->totalInBytes);
-                memcpy(zwd->headerBuf+zwd->totalInBytes, strm->next_in, srcSize);
-                strm->total_in += srcSize;
-                zwd->totalInBytes += srcSize;
-                strm->next_in += srcSize;
-                strm->avail_in -= srcSize;
-                if (zwd->totalInBytes < ZLIB_HEADERSIZE) return Z_OK;
-
-                if (MEM_readLE32(zwd->headerBuf) != ZSTD_MAGICNUMBER) {
-                    z_stream strm2;
-                    strm2.next_in = strm->next_in;
-                    strm2.avail_in = strm->avail_in;
-                    strm2.next_out = strm->next_out;
-                    strm2.avail_out = strm->avail_out;
-
-                    if (zwd->windowBits)
-                        errorCode = inflateInit2_(strm, zwd->windowBits, zwd->version, zwd->stream_size);
-                    else
-                        errorCode = inflateInit_(strm, zwd->version, zwd->stream_size);
-                    LOG_WRAPPERD("ZLIB inflateInit errorCode=%d\n", (int)errorCode);
-                    if (errorCode != Z_OK) return ZWRAPD_finishWithError(zwd, strm, (int)errorCode);
-
-                    /* inflate header */
-                    strm->next_in = (unsigned char*)zwd->headerBuf;
-                    strm->avail_in = ZLIB_HEADERSIZE;
-                    strm->avail_out = 0;
-                    errorCode = inflate(strm, Z_NO_FLUSH);
-                    LOG_WRAPPERD("ZLIB inflate errorCode=%d strm->avail_in=%d\n", (int)errorCode, (int)strm->avail_in);
-                    if (errorCode != Z_OK) return ZWRAPD_finishWithError(zwd, strm, (int)errorCode);
-                    if (strm->avail_in > 0) goto error;
-
-                    strm->next_in = strm2.next_in;
-                    strm->avail_in = strm2.avail_in;
-                    strm->next_out = strm2.next_out;
-                    strm->avail_out = strm2.avail_out;
-
-                    strm->reserved = ZWRAP_ZLIB_STREAM; /* mark as zlib stream */
-                    errorCode = ZWRAP_freeDCtx(zwd);
-                    if (ZSTD_isError(errorCode)) goto error;
-
-                    if (flush == Z_INFLATE_SYNC) res = inflateSync(strm);
-                    else res = inflate(strm, flush);
-                    LOG_WRAPPERD("- inflate2 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d res=%d\n", (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out, res);
-                    return res;
+    if (zwd == NULL) return Z_STREAM_ERROR;
+    if (zwd->decompState == ZWRAP_streamEnd) return Z_STREAM_END;
+
+    if (zwd->totalInBytes < ZLIB_HEADERSIZE) {
+        if (zwd->totalInBytes == 0 && strm->avail_in >= ZLIB_HEADERSIZE) {
+            if (MEM_readLE32(strm->next_in) != ZSTD_MAGICNUMBER) {
+                {   int const initErr = (zwd->windowBits) ?
+                                inflateInit2_(strm, zwd->windowBits, zwd->version, zwd->stream_size) :
+                                inflateInit_(strm, zwd->version, zwd->stream_size);
+                    LOG_WRAPPERD("ZLIB inflateInit errorCode=%d\n", initErr);
+                    if (initErr != Z_OK) return ZWRAPD_finishWithError(zwd, strm, initErr);
                 }
-            }
-        }
-
-        strm->reserved = ZWRAP_ZSTD_STREAM; /* mark as zstd steam */
 
-        if (flush == Z_INFLATE_SYNC) { strm->msg = "inflateSync is not supported!"; goto error; }
+                strm->reserved = ZWRAP_ZLIB_STREAM;
+                { size_t const freeErr = ZWRAP_freeDCtx(zwd);
+                  if (ZSTD_isError(freeErr)) goto error; }
+
+                {   int const result = (flush == Z_INFLATE_SYNC) ?
+                                        inflateSync(strm) :
+                                        inflate(strm, flush);
+                    LOG_WRAPPERD("- inflate3 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d res=%d\n",
+                                 (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out, res);
+                    return result;
+            }   }
+        } else {  /* ! (zwd->totalInBytes == 0 && strm->avail_in >= ZLIB_HEADERSIZE) */
+            size_t const srcSize = MIN(strm->avail_in, ZLIB_HEADERSIZE - zwd->totalInBytes);
+            memcpy(zwd->headerBuf+zwd->totalInBytes, strm->next_in, srcSize);
+            strm->total_in += srcSize;
+            zwd->totalInBytes += srcSize;
+            strm->next_in += srcSize;
+            strm->avail_in -= srcSize;
+            if (zwd->totalInBytes < ZLIB_HEADERSIZE) return Z_OK;
+
+            if (MEM_readLE32(zwd->headerBuf) != ZSTD_MAGICNUMBER) {
+                z_stream strm2;
+                strm2.next_in = strm->next_in;
+                strm2.avail_in = strm->avail_in;
+                strm2.next_out = strm->next_out;
+                strm2.avail_out = strm->avail_out;
+
+                {   int const initErr = (zwd->windowBits) ?
+                                inflateInit2_(strm, zwd->windowBits, zwd->version, zwd->stream_size) :
+                                inflateInit_(strm, zwd->version, zwd->stream_size);
+                    LOG_WRAPPERD("ZLIB inflateInit errorCode=%d\n", initErr);
+                    if (initErr != Z_OK) return ZWRAPD_finishWithError(zwd, strm, initErr);
+                }
 
-        if (!zwd->zbd) {
-            zwd->zbd = ZSTD_createDStream_advanced(zwd->customMem);
-            if (zwd->zbd == NULL) { LOG_WRAPPERD("ERROR: ZSTD_createDStream_advanced\n"); goto error; }
-            zwd->decompState = ZWRAP_useInit;
-        }
+                /* inflate header */
+                strm->next_in = (unsigned char*)zwd->headerBuf;
+                strm->avail_in = ZLIB_HEADERSIZE;
+                strm->avail_out = 0;
+                {   int const dErr = inflate(strm, Z_NO_FLUSH);
+                    LOG_WRAPPERD("ZLIB inflate errorCode=%d strm->avail_in=%d\n",
+                                  dErr, (int)strm->avail_in);
+                    if (dErr != Z_OK)
+                        return ZWRAPD_finishWithError(zwd, strm, dErr);
+                }
+                if (strm->avail_in > 0) goto error;
+
+                strm->next_in = strm2.next_in;
+                strm->avail_in = strm2.avail_in;
+                strm->next_out = strm2.next_out;
+                strm->avail_out = strm2.avail_out;
+
+                strm->reserved = ZWRAP_ZLIB_STREAM; /* mark as zlib stream */
+                { size_t const freeErr = ZWRAP_freeDCtx(zwd);
+                  if (ZSTD_isError(freeErr)) goto error; }
+
+                {   int const result = (flush == Z_INFLATE_SYNC) ?
+                                       inflateSync(strm) :
+                                       inflate(strm, flush);
+                    LOG_WRAPPERD("- inflate2 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d res=%d\n",
+                                 (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out, res);
+                    return result;
+        }   }   }  /* if ! (zwd->totalInBytes == 0 && strm->avail_in >= ZLIB_HEADERSIZE) */
+    }  /* (zwd->totalInBytes < ZLIB_HEADERSIZE) */
+
+    strm->reserved = ZWRAP_ZSTD_STREAM; /* mark as zstd steam */
+
+    if (flush == Z_INFLATE_SYNC) { strm->msg = "inflateSync is not supported!"; goto error; }
+
+    if (!zwd->zbd) {
+        zwd->zbd = ZSTD_createDStream_advanced(zwd->customMem);
+        if (zwd->zbd == NULL) { LOG_WRAPPERD("ERROR: ZSTD_createDStream_advanced\n"); goto error; }
+        zwd->decompState = ZWRAP_useInit;
+    }
 
-        if (zwd->totalInBytes < ZSTD_HEADERSIZE)
-        {
-            if (zwd->totalInBytes == 0 && strm->avail_in >= ZSTD_HEADERSIZE) {
-                if (zwd->decompState == ZWRAP_useInit) {
-                    errorCode = ZSTD_initDStream(zwd->zbd);
-                    if (ZSTD_isError(errorCode)) { LOG_WRAPPERD("ERROR: ZSTD_initDStream errorCode=%s\n", ZSTD_getErrorName(errorCode)); goto error; }
-                } else {
-                    errorCode = ZSTD_resetDStream(zwd->zbd);
-                    if (ZSTD_isError(errorCode)) goto error;
+    if (zwd->totalInBytes < ZSTD_HEADERSIZE) {
+        if (zwd->totalInBytes == 0 && strm->avail_in >= ZSTD_HEADERSIZE) {
+            if (zwd->decompState == ZWRAP_useInit) {
+                size_t const initErr = ZSTD_initDStream(zwd->zbd);
+                if (ZSTD_isError(initErr)) {
+                    LOG_WRAPPERD("ERROR: ZSTD_initDStream errorCode=%s\n",
+                                 ZSTD_getErrorName(initErr));
+                    goto error;
                 }
             } else {
-                srcSize = MIN(strm->avail_in, ZSTD_HEADERSIZE - zwd->totalInBytes);
-                memcpy(zwd->headerBuf+zwd->totalInBytes, strm->next_in, srcSize);
-                strm->total_in += srcSize;
-                zwd->totalInBytes += srcSize;
-                strm->next_in += srcSize;
-                strm->avail_in -= srcSize;
-                if (zwd->totalInBytes < ZSTD_HEADERSIZE) return Z_OK;
-
-                if (zwd->decompState == ZWRAP_useInit) {
-                    errorCode = ZSTD_initDStream(zwd->zbd);
-                    if (ZSTD_isError(errorCode)) { LOG_WRAPPERD("ERROR: ZSTD_initDStream errorCode=%s\n", ZSTD_getErrorName(errorCode)); goto error; }
-                } else {
-                    errorCode = ZSTD_resetDStream(zwd->zbd);
-                    if (ZSTD_isError(errorCode)) goto error;
-                }
-
-                zwd->inBuffer.src = zwd->headerBuf;
-                zwd->inBuffer.size = ZSTD_HEADERSIZE;
-                zwd->inBuffer.pos = 0;
-                zwd->outBuffer.dst = strm->next_out;
-                zwd->outBuffer.size = 0;
-                zwd->outBuffer.pos = 0;
-                errorCode = ZSTD_decompressStream(zwd->zbd, &zwd->outBuffer, &zwd->inBuffer);
-                LOG_WRAPPERD("inflate ZSTD_decompressStream1 errorCode=%d srcSize=%d dstCapacity=%d\n", (int)errorCode, (int)zwd->inBuffer.size, (int)zwd->outBuffer.size);
-                if (ZSTD_isError(errorCode)) {
-                    LOG_WRAPPERD("ERROR: ZSTD_decompressStream1 %s\n", ZSTD_getErrorName(errorCode));
+                size_t const resetErr = ZSTD_resetDStream(zwd->zbd);
+                if (ZSTD_isError(resetErr)) goto error;
+            }
+        } else {
+            size_t const srcSize = MIN(strm->avail_in, ZSTD_HEADERSIZE - zwd->totalInBytes);
+            memcpy(zwd->headerBuf+zwd->totalInBytes, strm->next_in, srcSize);
+            strm->total_in += srcSize;
+            zwd->totalInBytes += srcSize;
+            strm->next_in += srcSize;
+            strm->avail_in -= srcSize;
+            if (zwd->totalInBytes < ZSTD_HEADERSIZE) return Z_OK;
+
+            if (zwd->decompState == ZWRAP_useInit) {
+                size_t const initErr = ZSTD_initDStream(zwd->zbd);
+                if (ZSTD_isError(initErr)) {
+                    LOG_WRAPPERD("ERROR: ZSTD_initDStream errorCode=%s\n",
+                                ZSTD_getErrorName(initErr));
                     goto error;
                 }
-                if (zwd->inBuffer.pos != zwd->inBuffer.size) goto error; /* not consumed */
+            } else {
+                size_t const resetErr = ZSTD_resetDStream(zwd->zbd);
+                if (ZSTD_isError(resetErr)) goto error;
             }
+
+            zwd->inBuffer.src = zwd->headerBuf;
+            zwd->inBuffer.size = ZSTD_HEADERSIZE;
+            zwd->inBuffer.pos = 0;
+            zwd->outBuffer.dst = strm->next_out;
+            zwd->outBuffer.size = 0;
+            zwd->outBuffer.pos = 0;
+            {   size_t const dErr = ZSTD_decompressStream(zwd->zbd, &zwd->outBuffer, &zwd->inBuffer);
+                LOG_WRAPPERD("inflate ZSTD_decompressStream1 errorCode=%d srcSize=%d dstCapacity=%d\n",
+                            (int)dErr, (int)zwd->inBuffer.size, (int)zwd->outBuffer.size);
+                if (ZSTD_isError(dErr)) {
+                    LOG_WRAPPERD("ERROR: ZSTD_decompressStream1 %s\n", ZSTD_getErrorName(dErr));
+                    goto error;
+            }   }
+            if (zwd->inBuffer.pos != zwd->inBuffer.size) goto error; /* not consumed */
         }
+    }   /* (zwd->totalInBytes < ZSTD_HEADERSIZE) */
 
-        zwd->inBuffer.src = strm->next_in;
-        zwd->inBuffer.size = strm->avail_in;
-        zwd->inBuffer.pos = 0;
-        zwd->outBuffer.dst = strm->next_out;
-        zwd->outBuffer.size = strm->avail_out;
-        zwd->outBuffer.pos = 0;
-        errorCode = ZSTD_decompressStream(zwd->zbd, &zwd->outBuffer, &zwd->inBuffer);
-        LOG_WRAPPERD("inflate ZSTD_decompressStream2 errorCode=%d srcSize=%d dstCapacity=%d\n", (int)errorCode, (int)strm->avail_in, (int)strm->avail_out);
-        if (ZSTD_isError(errorCode)) {
+    zwd->inBuffer.src = strm->next_in;
+    zwd->inBuffer.size = strm->avail_in;
+    zwd->inBuffer.pos = 0;
+    zwd->outBuffer.dst = strm->next_out;
+    zwd->outBuffer.size = strm->avail_out;
+    zwd->outBuffer.pos = 0;
+    {   size_t const dErr = ZSTD_decompressStream(zwd->zbd, &zwd->outBuffer, &zwd->inBuffer);
+        LOG_WRAPPERD("inflate ZSTD_decompressStream2 errorCode=%d srcSize=%d dstCapacity=%d\n",
+                    (int)dErr, (int)strm->avail_in, (int)strm->avail_out);
+        if (ZSTD_isError(dErr)) {
             zwd->errorCount++;
-            LOG_WRAPPERD("ERROR: ZSTD_decompressStream2 %s zwd->errorCount=%d\n", ZSTD_getErrorName(errorCode), zwd->errorCount);
+            LOG_WRAPPERD("ERROR: ZSTD_decompressStream2 %s zwd->errorCount=%d\n",
+                        ZSTD_getErrorName(dErr), zwd->errorCount);
             if (zwd->errorCount<=1) return Z_NEED_DICT; else goto error;
         }
-        LOG_WRAPPERD("inflate inBuffer.pos=%d inBuffer.size=%d outBuffer.pos=%d outBuffer.size=%d o\n", (int)zwd->inBuffer.pos, (int)zwd->inBuffer.size, (int)zwd->outBuffer.pos, (int)zwd->outBuffer.size);
+        LOG_WRAPPERD("inflate inBuffer.pos=%d inBuffer.size=%d outBuffer.pos=%d outBuffer.size=%d o\n",
+                    (int)zwd->inBuffer.pos, (int)zwd->inBuffer.size, (int)zwd->outBuffer.pos, (int)zwd->outBuffer.size);
         strm->next_out += zwd->outBuffer.pos;
         strm->total_out += zwd->outBuffer.pos;
         strm->avail_out -= zwd->outBuffer.pos;
@@ -799,13 +822,16 @@ ZEXTERN int ZEXPORT z_inflate OF((z_streamp strm, int flush))
         zwd->totalInBytes += zwd->inBuffer.pos;
         strm->next_in += zwd->inBuffer.pos;
         strm->avail_in -= zwd->inBuffer.pos;
-        if (errorCode == 0) {
-            LOG_WRAPPERD("inflate Z_STREAM_END1 avail_in=%d avail_out=%d total_in=%d total_out=%d\n", (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out);
+        if (dErr == 0) {
+            LOG_WRAPPERD("inflate Z_STREAM_END1 avail_in=%d avail_out=%d total_in=%d total_out=%d\n",
+                        (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out);
             zwd->decompState = ZWRAP_streamEnd;
             return Z_STREAM_END;
         }
-    }
-    LOG_WRAPPERD("- inflate2 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d res=%d\n", (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out, Z_OK);
+    }  /* dErr lifetime */
+
+    LOG_WRAPPERD("- inflate2 flush=%d avail_in=%d avail_out=%d total_in=%d total_out=%d res=%d\n",
+                (int)flush, (int)strm->avail_in, (int)strm->avail_out, (int)strm->total_in, (int)strm->total_out, Z_OK);
     return Z_OK;
 
 error:
@@ -818,13 +844,13 @@ ZEXTERN int ZEXPORT z_inflateEnd OF((z_streamp strm))
     if (g_ZWRAPdecompressionType == ZWRAP_FORCE_ZLIB || !strm->reserved)
         return inflateEnd(strm);
 
-    LOG_WRAPPERD("- inflateEnd total_in=%d total_out=%d\n", (int)(strm->total_in), (int)(strm->total_out));
-    {   size_t errorCode;
-        ZWRAP_DCtx* zwd = (ZWRAP_DCtx*) strm->state;
+    LOG_WRAPPERD("- inflateEnd total_in=%d total_out=%d\n",
+                (int)(strm->total_in), (int)(strm->total_out));
+    {   ZWRAP_DCtx* const zwd = (ZWRAP_DCtx*) strm->state;
         if (zwd == NULL) return Z_OK;  /* structures are already freed */
+        { size_t const freeErr = ZWRAP_freeDCtx(zwd);
+          if (ZSTD_isError(freeErr)) return Z_STREAM_ERROR; }
         strm->state = NULL;
-        errorCode = ZWRAP_freeDCtx(zwd);
-        if (ZSTD_isError(errorCode)) return Z_STREAM_ERROR;
     }
     return Z_OK;
 }
@@ -841,8 +867,6 @@ ZEXTERN int ZEXPORT z_inflateSync OF((z_streamp strm))
 
 
 
-
-
 /* Advanced compression functions */
 ZEXTERN int ZEXPORT z_deflateCopy OF((z_streamp dest,
                                     z_streamp source))
@@ -982,7 +1006,7 @@ ZEXTERN uLong ZEXPORT z_zlibCompileFlags OF((void)) { return zlibCompileFlags();
 
 
 
-                        /* utility functions */
+                    /* ===   utility functions  === */
 #ifndef Z_SOLO
 
 ZEXTERN int ZEXPORT z_compress OF((Bytef *dest,   uLongf *destLen,
@@ -991,11 +1015,14 @@ ZEXTERN int ZEXPORT z_compress OF((Bytef *dest,   uLongf *destLen,
     if (!g_ZWRAP_useZSTDcompression)
         return compress(dest, destLen, source, sourceLen);
 
-    { size_t dstCapacity = *destLen;
-      size_t const errorCode = ZSTD_compress(dest, dstCapacity, source, sourceLen, ZWRAP_DEFAULT_CLEVEL);
-      LOG_WRAPPERD("z_compress sourceLen=%d dstCapacity=%d\n", (int)sourceLen, (int)dstCapacity);
-      if (ZSTD_isError(errorCode)) return Z_STREAM_ERROR;
-      *destLen = errorCode;
+    {   size_t dstCapacity = *destLen;
+        size_t const cSize = ZSTD_compress(dest, dstCapacity,
+                                           source, sourceLen,
+                                           ZWRAP_DEFAULT_CLEVEL);
+        LOG_WRAPPERD("z_compress sourceLen=%d dstCapacity=%d\n",
+                    (int)sourceLen, (int)dstCapacity);
+        if (ZSTD_isError(cSize)) return Z_STREAM_ERROR;
+        *destLen = cSize;
     }
     return Z_OK;
 }
@@ -1009,9 +1036,9 @@ ZEXTERN int ZEXPORT z_compress2 OF((Bytef *dest,   uLongf *destLen,
         return compress2(dest, destLen, source, sourceLen, level);
 
     { size_t dstCapacity = *destLen;
-      size_t const errorCode = ZSTD_compress(dest, dstCapacity, source, sourceLen, level);
-      if (ZSTD_isError(errorCode)) return Z_STREAM_ERROR;
-      *destLen = errorCode;
+      size_t const cSize = ZSTD_compress(dest, dstCapacity, source, sourceLen, level);
+      if (ZSTD_isError(cSize)) return Z_STREAM_ERROR;
+      *destLen = cSize;
     }
     return Z_OK;
 }
@@ -1029,13 +1056,13 @@ ZEXTERN uLong ZEXPORT z_compressBound OF((uLong sourceLen))
 ZEXTERN int ZEXPORT z_uncompress OF((Bytef *dest,   uLongf *destLen,
                                    const Bytef *source, uLong sourceLen))
 {
-    if (sourceLen < 4 || MEM_readLE32(source) != ZSTD_MAGICNUMBER)
+    if (!ZSTD_isFrame(source, sourceLen))
         return uncompress(dest, destLen, source, sourceLen);
 
     { size_t dstCapacity = *destLen;
-      size_t const errorCode = ZSTD_decompress(dest, dstCapacity, source, sourceLen);
-      if (ZSTD_isError(errorCode)) return Z_STREAM_ERROR;
-      *destLen = errorCode;
+      size_t const dSize = ZSTD_decompress(dest, dstCapacity, source, sourceLen);
+      if (ZSTD_isError(dSize)) return Z_STREAM_ERROR;
+      *destLen = dSize;
      }
     return Z_OK;
 }