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diff --git a/net/samba411/files/man/talloc.3 b/net/samba411/files/man/talloc.3 deleted file mode 100644 index 6a10b4990c2e..000000000000 --- a/net/samba411/files/man/talloc.3 +++ /dev/null @@ -1,683 +0,0 @@ -'\" t -.\" Title: talloc -.\" Author: [see the "AUTHOR" section] -.\" Generator: DocBook XSL Stylesheets v1.76.1 <http://docbook.sf.net/> -.\" Date: 2015-04-10 -.\" Manual: System Administration tools -.\" Source: Samba 4.0 -.\" Language: English -.\" -.TH "TALLOC" "3" "2015\-04\-10" "Samba 4\&.0" "System Administration tools" -.\" ----------------------------------------------------------------- -.\" * Define some portability stuff -.\" ----------------------------------------------------------------- -.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -.\" http://bugs.debian.org/507673 -.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html -.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -.ie \n(.g .ds Aq \(aq -.el .ds Aq ' -.\" ----------------------------------------------------------------- -.\" * set default formatting -.\" ----------------------------------------------------------------- -.\" disable hyphenation -.nh -.\" disable justification (adjust text to left margin only) -.ad l -.\" ----------------------------------------------------------------- -.\" * MAIN CONTENT STARTS HERE * -.\" ----------------------------------------------------------------- -.SH "NAME" -talloc \- hierarchical reference counted memory pool system with destructors -.SH "SYNOPSIS" -.sp -.nf -#include <talloc\&.h> -.fi -.SH "DESCRIPTION" -.PP -If you are used to talloc from Samba3 then please read this carefully, as talloc has changed a lot\&. -.PP -The new talloc is a hierarchical, reference counted memory pool system with destructors\&. Quite a mouthful really, but not too bad once you get used to it\&. -.PP -Perhaps the biggest change from Samba3 is that there is no distinction between a "talloc context" and a "talloc pointer"\&. Any pointer returned from talloc() is itself a valid talloc context\&. This means you can do this: -.sp -.if n \{\ -.RS 4 -.\} -.nf - struct foo *X = talloc(mem_ctx, struct foo); - X\->name = talloc_strdup(X, "foo"); - -.fi -.if n \{\ -.RE -.\} -.PP -and the pointer -X\->name -would be a "child" of the talloc context -X -which is itself a child of -mem_ctx\&. So if you do -talloc_free(mem_ctx) -then it is all destroyed, whereas if you do -talloc_free(X) -then just -X -and -X\->name -are destroyed, and if you do -talloc_free(X\->name) -then just the name element of -X -is destroyed\&. -.PP -If you think about this, then what this effectively gives you is an n\-ary tree, where you can free any part of the tree with talloc_free()\&. -.PP -If you find this confusing, then I suggest you run the -testsuite -program to watch talloc in action\&. You may also like to add your own tests to -testsuite\&.c -to clarify how some particular situation is handled\&. -.SH "TALLOC API" -.PP -The following is a complete guide to the talloc API\&. Read it all at least twice\&. -.SS "(type *)talloc(const void *ctx, type);" -.PP -The talloc() macro is the core of the talloc library\&. It takes a memory -\fIctx\fR -and a -\fItype\fR, and returns a pointer to a new area of memory of the given -\fItype\fR\&. -.PP -The returned pointer is itself a talloc context, so you can use it as the -\fIctx\fR -argument to more calls to talloc() if you wish\&. -.PP -The returned pointer is a "child" of the supplied context\&. This means that if you talloc_free() the -\fIctx\fR -then the new child disappears as well\&. Alternatively you can free just the child\&. -.PP -The -\fIctx\fR -argument to talloc() can be NULL, in which case a new top level context is created\&. -.SS "void *talloc_size(const void *ctx, size_t size);" -.PP -The function talloc_size() should be used when you don\*(Aqt have a convenient type to pass to talloc()\&. Unlike talloc(), it is not type safe (as it returns a void *), so you are on your own for type checking\&. -.SS "(typeof(ptr)) talloc_ptrtype(const void *ctx, ptr);" -.PP -The talloc_ptrtype() macro should be used when you have a pointer and want to allocate memory to point at with this pointer\&. When compiling with gcc >= 3 it is typesafe\&. Note this is a wrapper of talloc_size() and talloc_get_name() will return the current location in the source file\&. and not the type\&. -.SS "int talloc_free(void *ptr);" -.PP -The talloc_free() function frees a piece of talloc memory, and all its children\&. You can call talloc_free() on any pointer returned by talloc()\&. -.PP -The return value of talloc_free() indicates success or failure, with 0 returned for success and \-1 for failure\&. The only possible failure condition is if -\fIptr\fR -had a destructor attached to it and the destructor returned \-1\&. See -\(lqtalloc_set_destructor()\(rq -for details on destructors\&. -.PP -If this pointer has an additional parent when talloc_free() is called then the memory is not actually released, but instead the most recently established parent is destroyed\&. See -\(lqtalloc_reference()\(rq -for details on establishing additional parents\&. -.PP -For more control on which parent is removed, see -\(lqtalloc_unlink()\(rq\&. -.PP -talloc_free() operates recursively on its children\&. -.PP -From the 2\&.0 version of talloc, as a special case, talloc_free() is refused on pointers that have more than one parent, as talloc would have no way of knowing which parent should be removed\&. To free a pointer that has more than one parent please use talloc_unlink()\&. -.PP -To help you find problems in your code caused by this behaviour, if you do try and free a pointer with more than one parent then the talloc logging function will be called to give output like this: -.PP - -.sp -.if n \{\ -.RS 4 -.\} -.nf - ERROR: talloc_free with references at some_dir/source/foo\&.c:123 - reference at some_dir/source/other\&.c:325 - reference at some_dir/source/third\&.c:121 - -.fi -.if n \{\ -.RE -.\} -.PP -Please see the documentation for talloc_set_log_fn() and talloc_set_log_stderr() for more information on talloc logging functions\&. -.SS "void *talloc_reference(const void *ctx, const void *ptr);" -.PP -The talloc_reference() function makes -\fIctx\fR -an additional parent of -\fIptr\fR\&. -.PP -The return value of talloc_reference() is always the original pointer -\fIptr\fR, unless talloc ran out of memory in creating the reference in which case it will return NULL (each additional reference consumes around 48 bytes of memory on intel x86 platforms)\&. -.PP -If -\fIptr\fR -is NULL, then the function is a no\-op, and simply returns NULL\&. -.PP -After creating a reference you can free it in one of the following ways: -.PP - -.sp -.RS 4 -.ie n \{\ -\h'-04'\(bu\h'+03'\c -.\} -.el \{\ -.sp -1 -.IP \(bu 2.3 -.\} -you can talloc_free() any parent of the original pointer\&. That will reduce the number of parents of this pointer by 1, and will cause this pointer to be freed if it runs out of parents\&. -.RE -.sp -.RS 4 -.ie n \{\ -\h'-04'\(bu\h'+03'\c -.\} -.el \{\ -.sp -1 -.IP \(bu 2.3 -.\} -you can talloc_free() the pointer itself if it has at maximum one parent\&. This behaviour has been changed since the release of version 2\&.0\&. Further informations in the description of "talloc_free"\&. -.RE -.PP -For more control on which parent to remove, see -\(lqtalloc_unlink()\(rq\&. -.SS "int talloc_unlink(const void *ctx, void *ptr);" -.PP -The talloc_unlink() function removes a specific parent from -\fIptr\fR\&. The -\fIctx\fR -passed must either be a context used in talloc_reference() with this pointer, or must be a direct parent of ptr\&. -.PP -Note that if the parent has already been removed using talloc_free() then this function will fail and will return \-1\&. Likewise, if -\fIptr\fR -is NULL, then the function will make no modifications and return \-1\&. -.PP -Usually you can just use talloc_free() instead of talloc_unlink(), but sometimes it is useful to have the additional control on which parent is removed\&. -.SS "void talloc_set_destructor(const void *ptr, int (*destructor)(void *));" -.PP -The function talloc_set_destructor() sets the -\fIdestructor\fR -for the pointer -\fIptr\fR\&. A -\fIdestructor\fR -is a function that is called when the memory used by a pointer is about to be released\&. The destructor receives -\fIptr\fR -as an argument, and should return 0 for success and \-1 for failure\&. -.PP -The -\fIdestructor\fR -can do anything it wants to, including freeing other pieces of memory\&. A common use for destructors is to clean up operating system resources (such as open file descriptors) contained in the structure the destructor is placed on\&. -.PP -You can only place one destructor on a pointer\&. If you need more than one destructor then you can create a zero\-length child of the pointer and place an additional destructor on that\&. -.PP -To remove a destructor call talloc_set_destructor() with NULL for the destructor\&. -.PP -If your destructor attempts to talloc_free() the pointer that it is the destructor for then talloc_free() will return \-1 and the free will be ignored\&. This would be a pointless operation anyway, as the destructor is only called when the memory is just about to go away\&. -.SS "int talloc_increase_ref_count(const void *\fIptr\fR);" -.PP -The talloc_increase_ref_count(\fIptr\fR) function is exactly equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc_reference(NULL, ptr); -.fi -.if n \{\ -.RE -.\} -.PP -You can use either syntax, depending on which you think is clearer in your code\&. -.PP -It returns 0 on success and \-1 on failure\&. -.SS "size_t talloc_reference_count(const void *\fIptr\fR);" -.PP -Return the number of references to the pointer\&. -.SS "void talloc_set_name(const void *ptr, const char *fmt, \&.\&.\&.);" -.PP -Each talloc pointer has a "name"\&. The name is used principally for debugging purposes, although it is also possible to set and get the name on a pointer in as a way of "marking" pointers in your code\&. -.PP -The main use for names on pointer is for "talloc reports"\&. See -\(lqtalloc_report_depth_cb()\(rq, -\(lqtalloc_report_depth_file()\(rq, -\(lqtalloc_report()\(rq -\(lqtalloc_report()\(rq -and -\(lqtalloc_report_full()\(rq -for details\&. Also see -\(lqtalloc_enable_leak_report()\(rq -and -\(lqtalloc_enable_leak_report_full()\(rq\&. -.PP -The talloc_set_name() function allocates memory as a child of the pointer\&. It is logically equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc_set_name_const(ptr, talloc_asprintf(ptr, fmt, \&.\&.\&.)); -.fi -.if n \{\ -.RE -.\} -.PP -Note that multiple calls to talloc_set_name() will allocate more memory without releasing the name\&. All of the memory is released when the ptr is freed using talloc_free()\&. -.SS "void talloc_set_name_const(const void *\fIptr\fR, const char *\fIname\fR);" -.PP -The function talloc_set_name_const() is just like talloc_set_name(), but it takes a string constant, and is much faster\&. It is extensively used by the "auto naming" macros, such as talloc_p()\&. -.PP -This function does not allocate any memory\&. It just copies the supplied pointer into the internal representation of the talloc ptr\&. This means you must not pass a -\fIname\fR -pointer to memory that will disappear before -\fIptr\fR -is freed with talloc_free()\&. -.SS "void *talloc_named(const void *\fIctx\fR, size_t \fIsize\fR, const char *\fIfmt\fR, \&.\&.\&.);" -.PP -The talloc_named() function creates a named talloc pointer\&. It is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -ptr = talloc_size(ctx, size); -talloc_set_name(ptr, fmt, \&.\&.\&.\&.); -.fi -.if n \{\ -.RE -.\} -.SS "void *talloc_named_const(const void *\fIctx\fR, size_t \fIsize\fR, const char *\fIname\fR);" -.PP -This is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -ptr = talloc_size(ctx, size); -talloc_set_name_const(ptr, name); -.fi -.if n \{\ -.RE -.\} -.SS "const char *talloc_get_name(const void *\fIptr\fR);" -.PP -This returns the current name for the given talloc pointer, -\fIptr\fR\&. See -\(lqtalloc_set_name()\(rq -for details\&. -.SS "void *talloc_init(const char *\fIfmt\fR, \&.\&.\&.);" -.PP -This function creates a zero length named talloc context as a top level context\&. It is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc_named(NULL, 0, fmt, \&.\&.\&.); -.fi -.if n \{\ -.RE -.\} -.SS "void *talloc_new(void *\fIctx\fR);" -.PP -This is a utility macro that creates a new memory context hanging off an existing context, automatically naming it "talloc_new: __location__" where __location__ is the source line it is called from\&. It is particularly useful for creating a new temporary working context\&. -.SS "(\fItype\fR *)talloc_realloc(const void *\fIctx\fR, void *\fIptr\fR, \fItype\fR, \fIcount\fR);" -.PP -The talloc_realloc() macro changes the size of a talloc pointer\&. It has the following equivalences: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc_realloc(ctx, NULL, type, 1) ==> talloc(ctx, type); -talloc_realloc(ctx, ptr, type, 0) ==> talloc_free(ptr); -.fi -.if n \{\ -.RE -.\} -.PP -The -\fIctx\fR -argument is only used if -\fIptr\fR -is not NULL, otherwise it is ignored\&. -.PP -talloc_realloc() returns the new pointer, or NULL on failure\&. The call will fail either due to a lack of memory, or because the pointer has more than one parent (see -\(lqtalloc_reference()\(rq)\&. -.SS "void *talloc_realloc_size(const void *ctx, void *ptr, size_t size);" -.PP -the talloc_realloc_size() function is useful when the type is not known so the type\-safe talloc_realloc() cannot be used\&. -.SS "TYPE *talloc_steal(const void *\fInew_ctx\fR, const TYPE *\fIptr\fR);" -.PP -The talloc_steal() function changes the parent context of a talloc pointer\&. It is typically used when the context that the pointer is currently a child of is going to be freed and you wish to keep the memory for a longer time\&. -.PP -The talloc_steal() function returns the pointer that you pass it\&. It does not have any failure modes\&. -.PP -It is possible to produce loops in the parent/child relationship if you are not careful with talloc_steal()\&. No guarantees are provided as to your sanity or the safety of your data if you do this\&. -.PP -Note that if you try and call talloc_steal() on a pointer that has more than one parent then the result is ambiguous\&. Talloc will choose to remove the parent that is currently indicated by talloc_parent() and replace it with the chosen parent\&. You will also get a message like this via the talloc logging functions: -.PP - -.sp -.if n \{\ -.RS 4 -.\} -.nf - WARNING: talloc_steal with references at some_dir/source/foo\&.c:123 - reference at some_dir/source/other\&.c:325 - reference at some_dir/source/third\&.c:121 - -.fi -.if n \{\ -.RE -.\} -.PP -To unambiguously change the parent of a pointer please see the function -\(lqtalloc_reparent()\(rq\&. See the talloc_set_log_fn() documentation for more information on talloc logging\&. -.SS "TYPE *talloc_reparent(const void *\fIold_parent\fR, const void *\fInew_parent\fR, const TYPE *\fIptr\fR);" -.PP -The talloc_reparent() function changes the parent context of a talloc pointer\&. It is typically used when the context that the pointer is currently a child of is going to be freed and you wish to keep the memory for a longer time\&. -.PP -The talloc_reparent() function returns the pointer that you pass it\&. It does not have any failure modes\&. -.PP -The difference between talloc_reparent() and talloc_steal() is that talloc_reparent() can specify which parent you wish to change\&. This is useful when a pointer has multiple parents via references\&. -.SS "TYPE *talloc_move(const void *\fInew_ctx\fR, TYPE **\fIptr\fR);" -.PP -The talloc_move() function is a wrapper around talloc_steal() which zeros the source pointer after the move\&. This avoids a potential source of bugs where a programmer leaves a pointer in two structures, and uses the pointer from the old structure after it has been moved to a new one\&. -.SS "size_t talloc_total_size(const void *\fIptr\fR);" -.PP -The talloc_total_size() function returns the total size in bytes used by this pointer and all child pointers\&. Mostly useful for debugging\&. -.PP -Passing NULL is allowed, but it will only give a meaningful result if talloc_enable_leak_report() or talloc_enable_leak_report_full() has been called\&. -.SS "size_t talloc_total_blocks(const void *\fIptr\fR);" -.PP -The talloc_total_blocks() function returns the total memory block count used by this pointer and all child pointers\&. Mostly useful for debugging\&. -.PP -Passing NULL is allowed, but it will only give a meaningful result if talloc_enable_leak_report() or talloc_enable_leak_report_full() has been called\&. -.SS "void talloc_report(const void *ptr, FILE *f);" -.PP -The talloc_report() function prints a summary report of all memory used by -\fIptr\fR\&. One line of report is printed for each immediate child of ptr, showing the total memory and number of blocks used by that child\&. -.PP -You can pass NULL for the pointer, in which case a report is printed for the top level memory context, but only if talloc_enable_leak_report() or talloc_enable_leak_report_full() has been called\&. -.SS "void talloc_report_full(const void *\fIptr\fR, FILE *\fIf\fR);" -.PP -This provides a more detailed report than talloc_report()\&. It will recursively print the entire tree of memory referenced by the pointer\&. References in the tree are shown by giving the name of the pointer that is referenced\&. -.PP -You can pass NULL for the pointer, in which case a report is printed for the top level memory context, but only if talloc_enable_leak_report() or talloc_enable_leak_report_full() has been called\&. -.SS "" -.HP \w'void\ talloc_report_depth_cb('u -.BI "void talloc_report_depth_cb(" "const\ void\ *ptr" ", " "int\ depth" ", " "int\ max_depth" ", " "void\ (*callback)(const\ void\ *ptr,\ int\ depth,\ int\ max_depth,\ int\ is_ref,\ void\ *priv)" ", " "void\ *priv" ");" -.PP -This provides a more flexible reports than talloc_report()\&. It will recursively call the callback for the entire tree of memory referenced by the pointer\&. References in the tree are passed with -\fIis_ref = 1\fR -and the pointer that is referenced\&. -.PP -You can pass NULL for the pointer, in which case a report is printed for the top level memory context, but only if talloc_enable_leak_report() or talloc_enable_leak_report_full() has been called\&. -.PP -The recursion is stopped when depth >= max_depth\&. max_depth = \-1 means only stop at leaf nodes\&. -.SS "" -.HP \w'void\ talloc_report_depth_file('u -.BI "void talloc_report_depth_file(" "const\ void\ *ptr" ", " "int\ depth" ", " "int\ max_depth" ", " "FILE\ *f" ");" -.PP -This provides a more flexible reports than talloc_report()\&. It will let you specify the depth and max_depth\&. -.SS "void talloc_enable_leak_report(void);" -.PP -This enables calling of talloc_report(NULL, stderr) when the program exits\&. In Samba4 this is enabled by using the \-\-leak\-report command line option\&. -.PP -For it to be useful, this function must be called before any other talloc function as it establishes a "null context" that acts as the top of the tree\&. If you don\*(Aqt call this function first then passing NULL to talloc_report() or talloc_report_full() won\*(Aqt give you the full tree printout\&. -.PP -Here is a typical talloc report: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc report on \*(Aqnull_context\*(Aq (total 267 bytes in 15 blocks) -libcli/auth/spnego_parse\&.c:55 contains 31 bytes in 2 blocks -libcli/auth/spnego_parse\&.c:55 contains 31 bytes in 2 blocks -iconv(UTF8,CP850) contains 42 bytes in 2 blocks -libcli/auth/spnego_parse\&.c:55 contains 31 bytes in 2 blocks -iconv(CP850,UTF8) contains 42 bytes in 2 blocks -iconv(UTF8,UTF\-16LE) contains 45 bytes in 2 blocks -iconv(UTF\-16LE,UTF8) contains 45 bytes in 2 blocks - -.fi -.if n \{\ -.RE -.\} -.SS "void talloc_enable_leak_report_full(void);" -.PP -This enables calling of talloc_report_full(NULL, stderr) when the program exits\&. In Samba4 this is enabled by using the \-\-leak\-report\-full command line option\&. -.PP -For it to be useful, this function must be called before any other talloc function as it establishes a "null context" that acts as the top of the tree\&. If you don\*(Aqt call this function first then passing NULL to talloc_report() or talloc_report_full() won\*(Aqt give you the full tree printout\&. -.PP -Here is a typical full report: -.sp -.if n \{\ -.RS 4 -.\} -.nf -full talloc report on \*(Aqroot\*(Aq (total 18 bytes in 8 blocks) -p1 contains 18 bytes in 7 blocks (ref 0) - r1 contains 13 bytes in 2 blocks (ref 0) - reference to: p2 - p2 contains 1 bytes in 1 blocks (ref 1) - x3 contains 1 bytes in 1 blocks (ref 0) - x2 contains 1 bytes in 1 blocks (ref 0) - x1 contains 1 bytes in 1 blocks (ref 0) - -.fi -.if n \{\ -.RE -.\} -.SS "(\fItype\fR *)talloc_zero(const void *\fIctx\fR, \fItype\fR);" -.PP -The talloc_zero() macro is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -ptr = talloc(ctx, type); -if (ptr) memset(ptr, 0, sizeof(type)); -.fi -.if n \{\ -.RE -.\} -.SS "void *talloc_zero_size(const void *\fIctx\fR, size_t \fIsize\fR)" -.PP -The talloc_zero_size() function is useful when you don\*(Aqt have a known type\&. -.SS "void *talloc_memdup(const void *\fIctx\fR, const void *\fIp\fR, size_t size);" -.PP -The talloc_memdup() function is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -ptr = talloc_size(ctx, size); -if (ptr) memcpy(ptr, p, size); -.fi -.if n \{\ -.RE -.\} -.SS "char *talloc_strdup(const void *\fIctx\fR, const char *\fIp\fR);" -.PP -The talloc_strdup() function is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -ptr = talloc_size(ctx, strlen(p)+1); -if (ptr) memcpy(ptr, p, strlen(p)+1); -.fi -.if n \{\ -.RE -.\} -.PP -This function sets the name of the new pointer to the passed string\&. This is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc_set_name_const(ptr, ptr) -.fi -.if n \{\ -.RE -.\} -.SS "char *talloc_strndup(const void *\fIt\fR, const char *\fIp\fR, size_t \fIn\fR);" -.PP -The talloc_strndup() function is the talloc equivalent of the C library function strndup(3)\&. -.PP -This function sets the name of the new pointer to the passed string\&. This is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc_set_name_const(ptr, ptr) -.fi -.if n \{\ -.RE -.\} -.SS "char *talloc_vasprintf(const void *\fIt\fR, const char *\fIfmt\fR, va_list \fIap\fR);" -.PP -The talloc_vasprintf() function is the talloc equivalent of the C library function vasprintf(3)\&. -.PP -This function sets the name of the new pointer to the new string\&. This is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc_set_name_const(ptr, ptr) -.fi -.if n \{\ -.RE -.\} -.SS "char *talloc_asprintf(const void *\fIt\fR, const char *\fIfmt\fR, \&.\&.\&.);" -.PP -The talloc_asprintf() function is the talloc equivalent of the C library function asprintf(3)\&. -.PP -This function sets the name of the new pointer to the passed string\&. This is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc_set_name_const(ptr, ptr) -.fi -.if n \{\ -.RE -.\} -.SS "char *talloc_asprintf_append(char *s, const char *fmt, \&.\&.\&.);" -.PP -The talloc_asprintf_append() function appends the given formatted string to the given string\&. -.PP -This function sets the name of the new pointer to the new string\&. This is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc_set_name_const(ptr, ptr) -.fi -.if n \{\ -.RE -.\} -.SS "(type *)talloc_array(const void *ctx, type, unsigned int count);" -.PP -The talloc_array() macro is equivalent to: -.sp -.if n \{\ -.RS 4 -.\} -.nf -(type *)talloc_size(ctx, sizeof(type) * count); -.fi -.if n \{\ -.RE -.\} -.PP -except that it provides integer overflow protection for the multiply, returning NULL if the multiply overflows\&. -.SS "void *talloc_array_size(const void *ctx, size_t size, unsigned int count);" -.PP -The talloc_array_size() function is useful when the type is not known\&. It operates in the same way as talloc_array(), but takes a size instead of a type\&. -.SS "(typeof(ptr)) talloc_array_ptrtype(const void *ctx, ptr, unsigned int count);" -.PP -The talloc_ptrtype() macro should be used when you have a pointer to an array and want to allocate memory of an array to point at with this pointer\&. When compiling with gcc >= 3 it is typesafe\&. Note this is a wrapper of talloc_array_size() and talloc_get_name() will return the current location in the source file\&. and not the type\&. -.SS "void *talloc_realloc_fn(const void *ctx, void *ptr, size_t size)" -.PP -This is a non\-macro version of talloc_realloc(), which is useful as libraries sometimes want a realloc function pointer\&. A realloc(3) implementation encapsulates the functionality of malloc(3), free(3) and realloc(3) in one call, which is why it is useful to be able to pass around a single function pointer\&. -.SS "void *talloc_autofree_context(void);" -.PP -This is a handy utility function that returns a talloc context which will be automatically freed on program exit\&. This can be used to reduce the noise in memory leak reports\&. -.SS "void *talloc_check_name(const void *ptr, const char *name);" -.PP -This function checks if a pointer has the specified -\fIname\fR\&. If it does then the pointer is returned\&. It it doesn\*(Aqt then NULL is returned\&. -.SS "(type *)talloc_get_type(const void *ptr, type);" -.PP -This macro allows you to do type checking on talloc pointers\&. It is particularly useful for void* private pointers\&. It is equivalent to this: -.sp -.if n \{\ -.RS 4 -.\} -.nf -(type *)talloc_check_name(ptr, #type) -.fi -.if n \{\ -.RE -.\} -.SS "talloc_set_type(const void *ptr, type);" -.PP -This macro allows you to force the name of a pointer to be a particular -\fItype\fR\&. This can be used in conjunction with talloc_get_type() to do type checking on void* pointers\&. -.PP -It is equivalent to this: -.sp -.if n \{\ -.RS 4 -.\} -.nf -talloc_set_name_const(ptr, #type) -.fi -.if n \{\ -.RE -.\} -.SS "talloc_set_log_fn(void (*log_fn)(const char *message));" -.PP -This function sets a logging function that talloc will use for warnings and errors\&. By default talloc will not print any warnings or errors\&. -.SS "talloc_set_log_stderr(void);" -.PP -This sets the talloc log function to write log messages to stderr -.SH "PERFORMANCE" -.PP -All the additional features of talloc(3) over malloc(3) do come at a price\&. We have a simple performance test in Samba4 that measures talloc() versus malloc() performance, and it seems that talloc() is about 10% slower than malloc() on my x86 Debian Linux box\&. For Samba, the great reduction in code complexity that we get by using talloc makes this worthwhile, especially as the total overhead of talloc/malloc in Samba is already quite small\&. -.SH "SEE ALSO" -.PP -malloc(3), strndup(3), vasprintf(3), asprintf(3), -\m[blue]\fB\%http://talloc.samba.org/\fR\m[] -.SH "AUTHOR" -.PP -The original Samba software and related utilities were created by Andrew Tridgell\&. Samba is now developed by the Samba Team as an Open Source project similar to the way the Linux kernel is developed\&. -.SH "COPYRIGHT/LICENSE" -.PP -Copyright (C) Andrew Tridgell 2004 -.PP -This program is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version\&. -.PP -This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE\&. See the GNU General Public License for more details\&. -.PP -You should have received a copy of the GNU General Public License along with this program; if not, see http://www\&.gnu\&.org/licenses/\&. |