Vendor import of clang trunk r126079:vendor/clang/clang-r126079

http://llvm.org/svn/llvm-project/cfe/trunk@126079

1 files changed, 94 insertions, 96 deletions

diff --git a/include/clang/Basic/FileManager.h b/include/clang/Basic/FileManager.h
index e71f51a0e700..563157fa8fbe 100644
--- a/include/clang/Basic/FileManager.h
+++ b/include/clang/Basic/FileManager.h
@@ -14,6 +14,7 @@
 #ifndef LLVM_CLANG_FILEMANAGER_H
 #define LLVM_CLANG_FILEMANAGER_H
 
+#include "clang/Basic/FileSystemOptions.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
@@ -22,12 +23,20 @@
 #include "llvm/Config/config.h" // for mode_t
 // FIXME: Enhance libsystem to support inode and other fields in stat.
 #include <sys/types.h>
-#include <sys/stat.h>
+
+struct stat;
+
+namespace llvm {
+class MemoryBuffer;
+namespace sys { class Path; }
+}
 
 namespace clang {
 class FileManager;
-
-/// DirectoryEntry - Cached information about one directory on the disk.
+class FileSystemStatCache;
+  
+/// DirectoryEntry - Cached information about one directory (either on
+/// the disk or in the virtual file system).
 ///
 class DirectoryEntry {
   const char *Name;   // Name of the directory.
@@ -37,7 +46,9 @@ public:
   const char *getName() const { return Name; }
 };
 
-/// FileEntry - Cached information about one file on the disk.
+/// FileEntry - Cached information about one file (either on the disk
+/// or in the virtual file system).  If the 'FD' member is valid, then
+/// this FileEntry has an open file descriptor for the file.
 ///
 class FileEntry {
   const char *Name;           // Name of the file.
@@ -48,12 +59,29 @@ class FileEntry {
   dev_t Device;               // ID for the device containing the file.
   ino_t Inode;                // Inode number for the file.
   mode_t FileMode;            // The file mode as returned by 'stat'.
+  
+  /// FD - The file descriptor for the file entry if it is opened and owned
+  /// by the FileEntry.  If not, this is set to -1.
+  mutable int FD;
   friend class FileManager;
+  
 public:
   FileEntry(dev_t device, ino_t inode, mode_t m)
-    : Name(0), Device(device), Inode(inode), FileMode(m) {}
+    : Name(0), Device(device), Inode(inode), FileMode(m), FD(-1) {}
   // Add a default constructor for use with llvm::StringMap
-  FileEntry() : Name(0), Device(0), Inode(0), FileMode(0) {}
+  FileEntry() : Name(0), Device(0), Inode(0), FileMode(0), FD(-1) {}
+
+  FileEntry(const FileEntry &FE) {
+    memcpy(this, &FE, sizeof(FE));
+    assert(FD == -1 && "Cannot copy a file-owning FileEntry");
+  }
+  
+  void operator=(const FileEntry &FE) {
+    memcpy(this, &FE, sizeof(FE));
+    assert(FD == -1 && "Cannot assign a file-owning FileEntry");
+  }
+
+  ~FileEntry();
 
   const char *getName() const { return Name; }
   off_t getSize() const { return Size; }
@@ -67,111 +95,68 @@ public:
   ///
   const DirectoryEntry *getDir() const { return Dir; }
 
-  bool operator<(const FileEntry& RHS) const {
+  bool operator<(const FileEntry &RHS) const {
     return Device < RHS.Device || (Device == RHS.Device && Inode < RHS.Inode);
   }
 };
 
-/// \brief Abstract interface for introducing a FileManager cache for 'stat'
-/// system calls, which is used by precompiled and pretokenized headers to
-/// improve performance.
-class StatSysCallCache {
-protected:
-  llvm::OwningPtr<StatSysCallCache> NextStatCache;
-  
-public:
-  virtual ~StatSysCallCache() {}
-  virtual int stat(const char *path, struct stat *buf) {
-    if (getNextStatCache())
-      return getNextStatCache()->stat(path, buf);
-    
-    return ::stat(path, buf);
-  }
-  
-  /// \brief Sets the next stat call cache in the chain of stat caches.
-  /// Takes ownership of the given stat cache.
-  void setNextStatCache(StatSysCallCache *Cache) {
-    NextStatCache.reset(Cache);
-  }
-  
-  /// \brief Retrieve the next stat call cache in the chain.
-  StatSysCallCache *getNextStatCache() { return NextStatCache.get(); }
-
-  /// \brief Retrieve the next stat call cache in the chain, transferring
-  /// ownership of this cache (and, transitively, all of the remaining caches)
-  /// to the caller.
-  StatSysCallCache *takeNextStatCache() { return NextStatCache.take(); }
-};
-
-/// \brief A stat "cache" that can be used by FileManager to keep
-/// track of the results of stat() calls that occur throughout the
-/// execution of the front end.
-class MemorizeStatCalls : public StatSysCallCache {
-public:
-  /// \brief The result of a stat() call.
-  ///
-  /// The first member is the result of calling stat(). If stat()
-  /// found something, the second member is a copy of the stat
-  /// structure.
-  typedef std::pair<int, struct stat> StatResult;
-
-  /// \brief The set of stat() calls that have been
-  llvm::StringMap<StatResult, llvm::BumpPtrAllocator> StatCalls;
-
-  typedef llvm::StringMap<StatResult, llvm::BumpPtrAllocator>::const_iterator
-    iterator;
-
-  iterator begin() const { return StatCalls.begin(); }
-  iterator end() const { return StatCalls.end(); }
-
-  virtual int stat(const char *path, struct stat *buf);
-};
-
 /// FileManager - Implements support for file system lookup, file system
 /// caching, and directory search management.  This also handles more advanced
 /// properties, such as uniquing files based on "inode", so that a file with two
 /// names (e.g. symlinked) will be treated as a single file.
 ///
 class FileManager {
+  FileSystemOptions FileSystemOpts;
 
   class UniqueDirContainer;
   class UniqueFileContainer;
 
-  /// UniqueDirs/UniqueFiles - Cache for existing directories/files.
+  /// UniqueRealDirs/UniqueRealFiles - Cache for existing real directories/files.
   ///
-  UniqueDirContainer &UniqueDirs;
-  UniqueFileContainer &UniqueFiles;
+  UniqueDirContainer &UniqueRealDirs;
+  UniqueFileContainer &UniqueRealFiles;
 
-  /// DirEntries/FileEntries - This is a cache of directory/file entries we have
-  /// looked up.  The actual Entry is owned by UniqueFiles/UniqueDirs above.
+  /// \brief The virtual directories that we have allocated.  For each
+  /// virtual file (e.g. foo/bar/baz.cpp), we add all of its parent
+  /// directories (foo/ and foo/bar/) here.
+  llvm::SmallVector<DirectoryEntry*, 4> VirtualDirectoryEntries;
+  /// \brief The virtual files that we have allocated.
+  llvm::SmallVector<FileEntry*, 4> VirtualFileEntries;
+
+  /// SeenDirEntries/SeenFileEntries - This is a cache that maps paths
+  /// to directory/file entries (either real or virtual) we have
+  /// looked up.  The actual Entries for real directories/files are
+  /// owned by UniqueRealDirs/UniqueRealFiles above, while the Entries
+  /// for virtual directories/files are owned by
+  /// VirtualDirectoryEntries/VirtualFileEntries above.
   ///
-  llvm::StringMap<DirectoryEntry*, llvm::BumpPtrAllocator> DirEntries;
-  llvm::StringMap<FileEntry*, llvm::BumpPtrAllocator> FileEntries;
+  llvm::StringMap<DirectoryEntry*, llvm::BumpPtrAllocator> SeenDirEntries;
+  llvm::StringMap<FileEntry*, llvm::BumpPtrAllocator> SeenFileEntries;
 
   /// NextFileUID - Each FileEntry we create is assigned a unique ID #.
   ///
   unsigned NextFileUID;
 
-  /// \brief The virtual files that we have allocated.
-  llvm::SmallVector<FileEntry *, 4> VirtualFileEntries;
-
   // Statistics.
   unsigned NumDirLookups, NumFileLookups;
   unsigned NumDirCacheMisses, NumFileCacheMisses;
 
   // Caching.
-  llvm::OwningPtr<StatSysCallCache> StatCache;
+  llvm::OwningPtr<FileSystemStatCache> StatCache;
 
-  int stat_cached(const char* path, struct stat* buf) {
-    return StatCache.get() ? StatCache->stat(path, buf) : stat(path, buf);
-  }
+  bool getStatValue(const char *Path, struct stat &StatBuf,
+                    int *FileDescriptor);
+
+  /// Add all ancestors of the given path (pointing to either a file
+  /// or a directory) as virtual directories.
+  void addAncestorsAsVirtualDirs(llvm::StringRef Path);
 
 public:
-  FileManager();
+  FileManager(const FileSystemOptions &FileSystemOpts);
   ~FileManager();
 
-  /// \brief Installs the provided StatSysCallCache object within
-  /// the FileManager. 
+  /// \brief Installs the provided FileSystemStatCache object within
+  /// the FileManager.
   ///
   /// Ownership of this object is transferred to the FileManager.
   ///
@@ -181,33 +166,46 @@ public:
   /// \param AtBeginning whether this new stat cache must be installed at the
   /// beginning of the chain of stat caches. Otherwise, it will be added to
   /// the end of the chain.
-  void addStatCache(StatSysCallCache *statCache, bool AtBeginning = false);
+  void addStatCache(FileSystemStatCache *statCache, bool AtBeginning = false);
 
-  /// \brief Removes the provided StatSysCallCache object from the file manager.
-  void removeStatCache(StatSysCallCache *statCache);
-  
-  /// getDirectory - Lookup, cache, and verify the specified directory.  This
-  /// returns null if the directory doesn't exist.
+  /// \brief Removes the specified FileSystemStatCache object from the manager.
+  void removeStatCache(FileSystemStatCache *statCache);
+
+  /// getDirectory - Lookup, cache, and verify the specified directory
+  /// (real or virtual).  This returns NULL if the directory doesn't exist.
   ///
-  const DirectoryEntry *getDirectory(llvm::StringRef Filename) {
-    return getDirectory(Filename.begin(), Filename.end());
-  }
-  const DirectoryEntry *getDirectory(const char *FileStart,const char *FileEnd);
+  const DirectoryEntry *getDirectory(llvm::StringRef DirName);
 
-  /// getFile - Lookup, cache, and verify the specified file.  This returns null
-  /// if the file doesn't exist.
+  /// getFile - Lookup, cache, and verify the specified file (real or
+  /// virtual).  This returns NULL if the file doesn't exist.
   ///
-  const FileEntry *getFile(llvm::StringRef Filename) {
-    return getFile(Filename.begin(), Filename.end());
-  }
-  const FileEntry *getFile(const char *FilenameStart,
-                           const char *FilenameEnd);
+  const FileEntry *getFile(llvm::StringRef Filename);
 
   /// \brief Retrieve a file entry for a "virtual" file that acts as
   /// if there were a file with the given name on disk. The file
   /// itself is not accessed.
   const FileEntry *getVirtualFile(llvm::StringRef Filename, off_t Size,
                                   time_t ModificationTime);
+
+  /// \brief Open the specified file as a MemoryBuffer, returning a new
+  /// MemoryBuffer if successful, otherwise returning null.
+  llvm::MemoryBuffer *getBufferForFile(const FileEntry *Entry,
+                                       std::string *ErrorStr = 0);
+  llvm::MemoryBuffer *getBufferForFile(llvm::StringRef Filename,
+                                       std::string *ErrorStr = 0);
+
+  /// \brief If path is not absolute and FileSystemOptions set the working
+  /// directory, the path is modified to be relative to the given
+  /// working directory.
+  static void FixupRelativePath(llvm::sys::Path &path,
+                                const FileSystemOptions &FSOpts);
+
+  
+  /// \brief Produce an array mapping from the unique IDs assigned to each
+  /// file to the corresponding FileEntry pointer.
+  void GetUniqueIDMapping(
+                    llvm::SmallVectorImpl<const FileEntry *> &UIDToFiles) const;
+  
   void PrintStats() const;
 };