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Diffstat (limited to 'lib/talloc/talloc.h')
| -rw-r--r-- | lib/talloc/talloc.h | 1590 |
1 files changed, 1523 insertions, 67 deletions
diff --git a/lib/talloc/talloc.h b/lib/talloc/talloc.h index f549a17fba..17f7dc1060 100644 --- a/lib/talloc/talloc.h +++ b/lib/talloc/talloc.h @@ -29,13 +29,108 @@ #include <stdio.h> #include <stdarg.h> +/** + * @defgroup talloc The talloc API + * + * talloc is a hierarchical, reference counted memory pool system with + * destructors. It is the core memory allocator used in Samba. + * + * Perhaps the biggest difference from other memory pool systems 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: + * + * @code + * struct foo *X = talloc(mem_ctx, struct foo); + * X->name = talloc_strdup(X, "foo"); + * @endcode + * + * 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. + * + * 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(). + * + * If you find this confusing, then run the testsuite 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. + * + * @section talloc_performance Performance + * + * All the additional features of talloc() over malloc() 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 4% 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. + * + * @section talloc_named Named blocks + * + * Every talloc chunk has a name that can be used as a dynamic type-checking + * system. If for some reason like a callback function you had to cast a + * "struct foo *" to a "void *" variable, later you can safely reassign the + * "void *" pointer to a "struct foo *" by using the talloc_get_type() or + * talloc_get_type_abort() macros. + * + * @code + * struct foo *X = talloc_get_type_abort(ptr, struct foo); + * @endcode + * + * This will abort if "ptr" does not contain a pointer that has been created + * with talloc(mem_ctx, struct foo). + * + * @section talloc_threading Multi-threading + * + * talloc itself does not deal with threads. It is thread-safe (assuming the + * underlying "malloc" is), as long as each thread uses different memory + * contexts. + * + * If two threads uses the same context then they need to synchronize in order + * to be safe. In particular: + * + * - when using talloc_enable_leak_report(), giving directly NULL as a parent + * context implicitly refers to a hidden "null context" global variable, so + * this should not be used in a multi-threaded environment without proper + * synchronization. + * - the context returned by talloc_autofree_context() is also global so + * shouldn't be used by several threads simultaneously without + * synchronization. + * + * @{ + */ + #define TALLOC_VERSION_MAJOR 2 #define TALLOC_VERSION_MINOR 0 int talloc_version_major(void); int talloc_version_minor(void); -/* this is only needed for compatibility with the old talloc */ +/** + * @brief Define a talloc parent type + * + * As talloc is a hierarchial memory allocator, every talloc chunk is a + * potential parent to other talloc chunks. So defining a separate type for a + * talloc chunk is not strictly necessary. TALLOC_CTX is defined nevertheless, + * as it provides an indicator for function arguments. You will frequently + * write code like + * + * @code + * struct foo *foo_create(TALLOC_CTX *mem_ctx) + * { + * struct foo *result; + * result = talloc(mem_ctx, struct foo); + * if (result == NULL) return NULL; + * ... initialize foo ... + * return result; + * } + * @endcode + * + * In this type of allocating functions it is handy to have a general + * TALLOC_CTX type to indicate which parent to put allocated structures on. + */ typedef void TALLOC_CTX; /* @@ -64,6 +159,229 @@ typedef void TALLOC_CTX; #endif #endif +#ifdef DOXYGEN +/** + * @brief Create a new talloc context. + * + * The talloc() macro is the core of the talloc library. It takes a memory + * context and a type, and returns a pointer to a new area of memory of the + * given type. + * + * The returned pointer is itself a talloc context, so you can use it as the + * context argument to more calls to talloc if you wish. + * + * The returned pointer is a "child" of the supplied context. This means that if + * you talloc_free() the context then the new child disappears as well. + * Alternatively you can free just the child. + * + * @param[in] ctx A talloc context to create a new reference on or NULL to + * create a new top level context. + * + * @param[in] type The type of memory to allocate. + * + * @return A type casted talloc context or NULL on error. + * + * @code + * unsigned int *a, *b; + * + * a = talloc(NULL, unsigned int); + * b = talloc(a, unsigned int); + * @endcode + * + * @see talloc_zero + * @see talloc_array + * @see talloc_steal + * @see talloc_free + */ +void *talloc(const void *ctx, #type); +#else +#define talloc(ctx, type) (type *)talloc_named_const(ctx, sizeof(type), #type) +void *_talloc(const void *context, size_t size); +#endif + +/** + * @brief Create a new top level talloc context. + * + * This function creates a zero length named talloc context as a top level + * context. It is equivalent to: + * + * @code + * talloc_named(NULL, 0, fmt, ...); + * @endcode + * @param[in] fmt Format string for the name. + * + * @param[in] ... Additional printf-style arguments. + * + * @return The allocated memory chunk, NULL on error. + * + * @see talloc_named() + */ +void *talloc_init(const char *fmt, ...) PRINTF_ATTRIBUTE(1,2); + +#ifdef DOXYGEN +/** + * @brief Free a chunk of talloc memory. + * + * This function frees a piece of talloc memory, and all its children. It + * operates recursively on its children. You can call talloc_free() on any + * pointer returned by talloc(). + * + * 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 talloc_reference() for details on + * establishing additional parents. + * + * For more control on which parent is removed, see talloc_unlink(). + * + * 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(). + * + * 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: + * + * @code + * 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 + * @endcode + * + * Please see the documentation for talloc_set_log_fn() and + * talloc_set_log_stderr() for more information on talloc logging + * functions. + * + * @param[in] ptr The chunk to be freed. + * + * @return Returns 0 on success and -1 on error. The only possible + * failure condition is if the pointer had a destructor + * attached to it and the destructor returned -1. + * + * Example: + * @code + * unsigned int *a, *b; + * a = talloc(NULL, unsigned int); + * b = talloc(a, unsigned int); + * + * talloc_free(a); // Frees a and b + * @endcode + * + * @see talloc_set_destructor() + * @see talloc_unlink() + */ +int talloc_free(void *ptr); +#else +#define talloc_free(ctx) _talloc_free(ctx, __location__) +int _talloc_free(void *ptr, const char *location); +#endif + +/** + * @brief Free a talloc chunk's children. + * + * The function walks along the list of all children of a talloc context and + * talloc_free()s only the children, not the context itself. + * + * @param[in] ptr The chunk that you want to free the children of. + */ +void talloc_free_children(void *ptr); + +#if DOXYGEN +/** + * @brief Assign a destructor function to be called when a chunk is freed. + * + * The function talloc_set_destructor() sets the "destructor" for the pointer + * "ptr". A destructor is a function that is called when the memory used by a + * pointer is about to be released. The destructor receives the pointer as an + * argument, and should return 0 for success and -1 for failure. + * + * The destructor 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. + * + * 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. + * + * To remove a destructor call talloc_set_destructor() with NULL for the + * destructor. + * + * 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. + * + * @param[in] ptr The talloc chunk to add a destructor to. + * + * @param[in] destructor The destructor function to be called. NULL to remove + * it. + * + * Example: + * @code + * static int destroy_fd(int *fd) { + * close(*fd); + * return 0; + * } + * + * int *open_file(const char *filename) { + * int *fd = talloc(NULL, int); + * *fd = open(filename, O_RDONLY); + * if (*fd < 0) { + * talloc_free(fd); + * return NULL; + * } + * // Whenever they free this, we close the file. + * talloc_set_destructor(fd, destroy_fd); + * return fd; + * } + * @endcode + * + * @see talloc() + * @see talloc_free() + */ +void talloc_set_destructor(const void *ptr, int (*destructor)(void *)); + +/** + * @brief Change a talloc chunk's parent. + * + * 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. + * + * To make the changed hierarchy less error-prone, you might consider to use + * talloc_move(). + * + * 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: + * + * @code + * 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 + * @endcode + * + * To unambiguously change the parent of a pointer please see the function + * talloc_reparent(). See the talloc_set_log_fn() documentation for more + * information on talloc logging. + * + * @param[in] new_ctx The new parent context. + * + * @param[in] ptr The talloc chunk to move. + * + * @return Returns the pointer that you pass it. It does not have + * any failure modes. + * + * @note 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. + */ +void *talloc_steal(const void *new_ctx, const void *ptr); +#else /* DOXYGEN */ /* try to make talloc_set_destructor() and talloc_steal() type safe, if we have a recent gcc */ #if (__GNUC__ >= 3) @@ -76,127 +394,1265 @@ typedef void TALLOC_CTX; /* this extremely strange macro is to avoid some braindamaged warning stupidity in gcc 4.1.x */ #define talloc_steal(ctx, ptr) ({ _TALLOC_TYPEOF(ptr) __talloc_steal_ret = (_TALLOC_TYPEOF(ptr))_talloc_steal_loc((ctx),(ptr), __location__); __talloc_steal_ret; }) -#else +#else /* __GNUC__ >= 3 */ #define talloc_set_destructor(ptr, function) \ _talloc_set_destructor((ptr), (int (*)(void *))(function)) #define _TALLOC_TYPEOF(ptr) void * #define talloc_steal(ctx, ptr) (_TALLOC_TYPEOF(ptr))_talloc_steal_loc((ctx),(ptr), __location__) -#endif +#endif /* __GNUC__ >= 3 */ +void _talloc_set_destructor(const void *ptr, int (*_destructor)(void *)); +void *_talloc_steal_loc(const void *new_ctx, const void *ptr, const char *location); +#endif /* DOXYGEN */ -#define talloc_reference(ctx, ptr) (_TALLOC_TYPEOF(ptr))_talloc_reference_loc((ctx),(ptr), __location__) +/** + * @brief Assign a name to a talloc chunk. + * + * 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. + * + * The main use for names on pointer is for "talloc reports". See + * talloc_report() and talloc_report_full() for details. Also see + * talloc_enable_leak_report() and talloc_enable_leak_report_full(). + * + * The talloc_set_name() function allocates memory as a child of the + * pointer. It is logically equivalent to: + * + * @code + * talloc_set_name_const(ptr, talloc_asprintf(ptr, fmt, ...)); + * @endcode + * + * @param[in] ptr The talloc chunk to assign a name to. + * + * @param[in] fmt Format string for the name. + * + * @param[in] ... Add printf-style additional arguments. + * + * @return The assigned name, NULL on error. + * + * @note 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(). + */ +const char *talloc_set_name(const void *ptr, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3); + +#ifdef DOXYGEN +/** + * @brief Change a talloc chunk's parent. + * + * This function has the same effect as talloc_steal(), and additionally sets + * the source pointer to NULL. You would use it like this: + * + * @code + * struct foo *X = talloc(tmp_ctx, struct foo); + * struct foo *Y; + * Y = talloc_move(new_ctx, &X); + * @endcode + * + * @param[in] new_ctx The new parent context. + * + * @param[in] ptr Pointer to the talloc chunk to move. + * + * @return The pointer of the talloc chunk it has been moved to, + * NULL on error. + */ +void *talloc_move(const void *new_ctx, const void *ptr); +#else #define talloc_move(ctx, ptr) (_TALLOC_TYPEOF(*(ptr)))_talloc_move((ctx),(void *)(ptr)) +void *_talloc_move(const void *new_ctx, const void *pptr); +#endif -/* useful macros for creating type checked pointers */ -#define talloc(ctx, type) (type *)talloc_named_const(ctx, sizeof(type), #type) +/** + * @brief Assign a name to a talloc chunk. + * + * The function 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(). + * + * 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 name pointer to memory that will disappear before the ptr + * is freed with talloc_free(). + * + * @param[in] ptr The talloc chunk to assign a name to. + * + * @param[in] name Format string for the name. + */ +void talloc_set_name_const(const void *ptr, const char *name); + +/** + * @brief Create a named talloc chunk. + * + * The talloc_named() function creates a named talloc pointer. It is + * equivalent to: + * + * @code + * ptr = talloc_size(context, size); + * talloc_set_name(ptr, fmt, ....); + * @endcode + * + * @param[in] context The talloc context to hang the result off. + * + * @param[in] size Number of char's that you want to allocate. + * + * @param[in] fmt Format string for the name. + * + * @param[in] ... Additional printf-style arguments. + * + * @return The allocated memory chunk, NULL on error. + * + * @see talloc_set_name() + */ +void *talloc_named(const void *context, size_t size, + const char *fmt, ...) PRINTF_ATTRIBUTE(3,4); + +/** + * @brief Basic routine to allocate a chunk of memory. + * + * This is equivalent to: + * + * @code + * ptr = talloc_size(context, size); + * talloc_set_name_const(ptr, name); + * @endcode + * + * @param[in] context The parent context. + * + * @param[in] size The number of char's that we want to allocate. + * + * @param[in] name The name the talloc block has. + * + * @return The allocated memory chunk, NULL on error. + */ +void *talloc_named_const(const void *context, size_t size, const char *name); + +#ifdef DOXYGEN +/** + * @brief Untyped allocation. + * + * The function should be used when you don't 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. + * + * Best to use talloc() or talloc_array() instead. + * + * @param[in] ctx The talloc context to hang the result off. + * + * @param[in] size Number of char's that you want to allocate. + * + * @return The allocated memory chunk, NULL on error. + * + * Example: + * @code + * void *mem = talloc_size(NULL, 100); + * @endcode + */ +void *talloc_size(const void *ctx, size_t size); +#else #define talloc_size(ctx, size) talloc_named_const(ctx, size, __location__) +#endif + +#ifdef DOXYGEN +/** + * @brief Allocate into a typed pointer. + * + * 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. + * + * @param[in] ctx The talloc context to hang the result off. + * + * @param[in] type The pointer you want to assign the result to. + * + * @return The properly casted allocated memory chunk, NULL on + * error. + * + * Example: + * @code + * unsigned int *a = talloc_ptrtype(NULL, a); + * @endcode + */ +void *talloc_ptrtype(const void *ctx, #type); +#else #define talloc_ptrtype(ctx, ptr) (_TALLOC_TYPEOF(ptr))talloc_size(ctx, sizeof(*(ptr))) +#endif +#ifdef DOXYGEN +/** + * @brief Allocate a new 0-sized talloc chunk. + * + * This is a utility macro that creates a new memory context hanging off an + * exiting 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. + * + * @param[in] ctx The talloc parent context. + * + * @return A new talloc chunk, NULL on error. + */ +void *talloc_new(const void *ctx); +#else #define talloc_new(ctx) talloc_named_const(ctx, 0, "talloc_new: " __location__) +#endif + +#ifdef DOXYGEN +/** + * @brief Allocate a 0-initizialized structure. + * + * The macro is equivalent to: + * + * @code + * ptr = talloc(ctx, type); + * if (ptr) memset(ptr, 0, sizeof(type)); + * @endcode + * + * @param[in] ctx The talloc context to hang the result off. + * + * @param[in] type The type that we want to allocate. + * + * @return Pointer to a piece of memory, properly cast to 'type *', + * NULL on error. + * + * Example: + * @code + * unsigned int *a, *b; + * a = talloc_zero(NULL, unsigned int); + * b = talloc_zero(a, unsigned int); + * @endcode + * + * @see talloc() + * @see talloc_zero_size() + * @see talloc_zero_array() + */ +void *talloc_zero(const void *ctx, #type); +/** + * @brief Allocate untyped, 0-initialized memory. + * + * @param[in] ctx The talloc context to hang the result off. + * + * @param[in] size Number of char's that you want to allocate. + * + * @return The allocated memory chunk. + */ +void *talloc_zero_size(const void *ctx, size_t size); +#else #define talloc_zero(ctx, type) (type *)_talloc_zero(ctx, sizeof(type), #type) #define talloc_zero_size(ctx, size) _talloc_zero(ctx, size, __location__) +void *_talloc_zero(const void *ctx, size_t size, const char *name); +#endif -#define talloc_zero_array(ctx, type, count) (type *)_talloc_zero_array(ctx, sizeof(type), count, #type) -#define talloc_array(ctx, type, count) (type *)_talloc_array(ctx, sizeof(type), count, #type) -#define talloc_array_size(ctx, size, count) _talloc_array(ctx, size, count, __location__) -#define talloc_array_ptrtype(ctx, ptr, count) (_TALLOC_TYPEOF(ptr))talloc_array_size(ctx, sizeof(*(ptr)), count) -#define talloc_array_length(ctx) (talloc_get_size(ctx)/sizeof(*ctx)) +/** + * @brief Return the name of a talloc chunk. + * + * @param[in] ptr The talloc chunk. + * + * @return The current name for the given talloc pointer. + * + * @see talloc_set_name() + */ +const char *talloc_get_name(const void *ptr); -#define talloc_realloc(ctx, p, type, count) (type *)_talloc_realloc_array(ctx, p, sizeof(type), count, #type) -#define talloc_realloc_size(ctx, ptr, size) _talloc_realloc(ctx, ptr, size, __location__) +/** + * @brief Verify that a talloc chunk carries a specified name. + * + * This function checks if a pointer has the specified name. If it does + * then the pointer is returned. + * + * @param[in] ptr The talloc chunk to check. + * + * @param[in] name The name to check against. + * + * @return The pointer if the name matches, NULL if it doesn't. + */ +void *talloc_check_name(const void *ptr, const char *name); +/** + * @brief Get the parent chunk of a pointer. + * + * @param[in] ptr The talloc pointer to inspect. + * + * @return The talloc parent of ptr, NULL on error. + */ +void *talloc_parent(const void *ptr); + +/** + * @brief Get a talloc chunk's parent name. + * + * @param[in] ptr The talloc pointer to inspect. + * + * @return The name of ptr's parent chunk. + */ +const char *talloc_parent_name(const void *ptr); + +/** + * @brief Get the total size of a talloc chunk including its children. + * + * The function returns the total size in bytes used by this pointer and all + * child pointers. Mostly useful for debugging. + * + * 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. + * + * @param[in] ptr The talloc chunk. + * + * @return The total size. + */ +size_t talloc_total_size(const void *ptr); + +/** + * @brief Get the number of talloc chunks hanging off a chunk. + * + * The talloc_total_blocks() function returns the total memory block + * count used by this pointer and all child pointers. Mostly useful for + * debugging. + * + * 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. + * + * @param[in] ptr The talloc chunk. + * + * @return The total size. + */ +size_t talloc_total_blocks(const void *ptr); + +#ifdef DOXYGEN +/** + * @brief Duplicate a memory area into a talloc chunk. + * + * The function is equivalent to: + * + * @code + * ptr = talloc_size(ctx, size); + * if (ptr) memcpy(ptr, p, size); + * @endcode + * + * @param[in] t The talloc context to hang the result off. + * + * @param[in] p The memory chunk you want to duplicate. + * + * @param[in] size Number of char's that you want copy. + * + * @return The allocated memory chunk. + * + * @see talloc_size() + */ +void *talloc_memdup(const void *t, const void *p, size_t size); +#else #define talloc_memdup(t, p, size) _talloc_memdup(t, p, size, __location__) +void *_talloc_memdup(const void *t, const void *p, size_t size, const char *name); +#endif + +#ifdef DOXYGEN +/** + * @brief Assign a type to a talloc chunk. + * + * This macro allows you to force the name of a pointer to be a particular type. + * This can be used in conjunction with talloc_get_type() to do type checking on + * void* pointers. + * + * It is equivalent to this: + * + * @code + * talloc_set_name_const(ptr, #type) + * @endcode + * + * @param[in] ptr The talloc chunk to assign the type to. + * + * @param[in] type The type to assign. + */ +void talloc_set_type(const char *ptr, #type); +/** + * @brief Get a typed pointer out of a talloc pointer. + * + * This macro allows you to do type checking on talloc pointers. It is + * particularly useful for void* private pointers. It is equivalent to + * this: + * + * @code + * (type *)talloc_check_name(ptr, #type) + * @endcode + * + * @param[in] ptr The talloc pointer to check. + * + * @param[in] type The type to check against. + * + * @return The properly casted pointer given by ptr, NULL on error. + */ +void *talloc_get_name(const void *ptr, #type); +#else #define talloc_set_type(ptr, type) talloc_set_name_const(ptr, #type) #define talloc_get_type(ptr, type) (type *)talloc_check_name(ptr, #type) -#define talloc_get_type_abort(ptr, type) (type *)_talloc_get_type_abort(ptr, #type, __location__) +#endif -#define talloc_find_parent_bytype(ptr, type) (type *)talloc_find_parent_byname(ptr, #type) -#define talloc_free(ctx) _talloc_free(ctx, __location__) +#ifdef DOXYGEN +/** + * @brief Safely turn a void pointer into a typed pointer. + * + * This macro is used together with talloc(mem_ctx, struct foo). If you had to + * assing the talloc chunk pointer to some void pointer variable, + * talloc_get_type_abort() is the recommended way to get the convert the void + * pointer back to a typed pointer. + * + * @param[in] ptr The void pointer to convert. + * + * @param[in] type The type that this chunk contains + * + * @return The ame value as ptr, type-checked and properly cast. + */ +void *talloc_get_type_abort(const void *ptr, #type); +#else +#define talloc_get_type_abort(ptr, type) (type *)_talloc_get_type_abort(ptr, #type, __location__) +void *_talloc_get_type_abort(const void *ptr, const char *name, const char *location); +#endif +/** + * @brief Find a parent context by name. + * + * Find a parent memory context of the current context that has the given + * name. This can be very useful in complex programs where it may be + * difficult to pass all information down to the level you need, but you + * know the structure you want is a parent of another context. + * + * @param[in] ctx The talloc chunk to start from. + * + * @param[in] name The name of the parent we look for. + * + * @return The memory context we are looking for, NULL if not + * found. + */ +void *talloc_find_parent_byname(const void *ctx, const char *name); -#if TALLOC_DEPRECATED -#define talloc_zero_p(ctx, type) talloc_zero(ctx, type) -#define talloc_p(ctx, type) talloc(ctx, type) -#define talloc_array_p(ctx, type, count) talloc_array(ctx, type, count) -#define talloc_realloc_p(ctx, p, type, count) talloc_realloc(ctx, p, type, count) -#define talloc_destroy(ctx) talloc_free(ctx) -#define talloc_append_string(c, s, a) (s?talloc_strdup_append(s,a):talloc_strdup(c, a)) +#ifdef DOXYGEN +/** + * @brief Find a parent context by type. + * + * Find a parent memory context of the current context that has the given + * name. This can be very useful in complex programs where it may be + * difficult to pass all information down to the level you need, but you + * know the structure you want is a parent of another context. + * + * Like talloc_find_parent_byname() but takes a type, making it typesafe. + * + * @param[in] ptr The talloc chunk to start from. + * + * @param[in] type The type of the parent to look for. + * + * @return The memory context we are looking for, NULL if not + * found. + */ +void *talloc_find_parent_bytype(const void *ptr, #type); +#else +#define talloc_find_parent_bytype(ptr, type) (type *)talloc_find_parent_byname(ptr, #type) #endif +/** + * @brief Allocate a talloc pool. + * + * A talloc pool is a pure optimization for specific situations. In the + * release process for Samba 3.2 we found out that we had become considerably + * slower than Samba 3.0 was. Profiling showed that malloc(3) was a large CPU + * consumer in benchmarks. For Samba 3.2 we have internally converted many + * static buffers to dynamically allocated ones, so malloc(3) being beaten + * more was no surprise. But it made us slower. + * + * talloc_pool() is an optimization to call malloc(3) a lot less for the use + * pattern Samba has: The SMB protocol is mainly a request/response protocol + * where we have to allocate a certain amount of memory per request and free + * that after the SMB reply is sent to the client. + * + * talloc_pool() creates a talloc chunk that you can use as a talloc parent + * exactly as you would use any other ::TALLOC_CTX. The difference is that + * when you talloc a child of this pool, no malloc(3) is done. Instead, talloc + * just increments a pointer inside the talloc_pool. This also works + * recursively. If you use the child of the talloc pool as a parent for + * grand-children, their memory is also taken from the talloc pool. + * + * If you talloc_free() children of a talloc pool, the memory is not given + * back to the system. Instead, free(3) is only called if the talloc_pool() + * itself is released with talloc_free(). + * + * The downside of a talloc pool is that if you talloc_move() a child of a + * talloc pool to a talloc parent outside the pool, the whole pool memory is + * not free(3)'ed until that moved chunk is also talloc_free()ed. + * + * @param[in] context The talloc context to hang the result off. + * + * @param[in] size Size of the talloc pool. + * + * @return The allocated talloc pool, NULL on error. + */ +void *talloc_pool(const void *context, size_t size); + +/** + * @brief Free a talloc chunk and NULL out the pointer. + * + * TALLOC_FREE() frees a pointer and sets it to NULL. Use this if you want + * immediate feedback (i.e. crash) if you use a pointer after having free'ed + * it. + * + * @param[in] ctx The chunk to be freed. + */ #define TALLOC_FREE(ctx) do { talloc_free(ctx); ctx=NULL; } while(0) -/* The following definitions come from talloc.c */ -void *_talloc(const void *context, size_t size); -void *talloc_pool(const void *context, size_t size); -void _talloc_set_destructor(const void *ptr, int (*_destructor)(void *)); +/* @} ******************************************************************/ + +/** + * \defgroup talloc_ref The talloc reference function. + * @ingroup talloc + * + * This module contains the definitions around talloc references + * + * @{ + */ + +/** + * @brief Increase the reference count of a talloc chunk. + * + * The talloc_increase_ref_count(ptr) function is exactly equivalent to: + * + * @code + * talloc_reference(NULL, ptr); + * @endcode + * + * You can use either syntax, depending on which you think is clearer in + * your code. + * + * @param[in] ptr The pointer to increase the reference count. + * + * @return 0 on success, -1 on error. + */ int talloc_increase_ref_count(const void *ptr); + +/** + * @brief Get the number of references to a talloc chunk. + * + * @param[in] ptr The pointer to retrieve the reference count from. + * + * @return The number of references. + */ size_t talloc_reference_count(const void *ptr); + +#ifdef DOXYGEN +/** + * @brief Create an additional talloc parent to a pointer. + * + * The talloc_reference() function makes "context" an additional parent of + * ptr. Each additional reference consumes around 48 bytes of memory on intel + * x86 platforms. + * + * If ptr is NULL, then the function is a no-op, and simply returns NULL. + * + * After creating a reference you can free it in one of the following ways: + * + * - 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. + * + * - you can talloc_free() the pointer itself. That will destroy the + * most recently established parent to the pointer and leave the + * pointer as a child of its current parent. + * + * For more control on which parent to remove, see talloc_unlink() + * @param[in] ctx The additional parent. + * + * @param[in] ptr The pointer you want to create an additional parent for. + * + * @return The original pointer 'ptr', NULL if talloc ran out of + * memory in creating the reference. + * + * Example: + * @code + * unsigned int *a, *b, *c; + * a = talloc(NULL, unsigned int); + * b = talloc(NULL, unsigned int); + * c = talloc(a, unsigned int); + * // b also serves as a parent of c. + * talloc_reference(b, c); + * @endcode + * + * @see talloc_unlink() + */ +void *talloc_reference(const void *ctx, const void *ptr); +#else +#define talloc_reference(ctx, ptr) (_TALLOC_TYPEOF(ptr))_talloc_reference_loc((ctx),(ptr), __location__) void *_talloc_reference_loc(const void *context, const void *ptr, const char *location); +#endif + +/** + * @brief Remove a specific parent from a talloc chunk. + * + * The function removes a specific parent from ptr. The context passed must + * either be a context used in talloc_reference() with this pointer, or must be + * a direct parent of ptr. + * + * 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. + * + * @param[in] context The talloc parent to remove. + * + * @param[in] ptr The talloc ptr you want to remove the parent from. + * + * @return 0 on success, -1 on error. + * + * @note If the parent has already been removed using talloc_free() then + * this function will fail and will return -1. Likewise, if ptr is NULL, + * then the function will make no modifications and return -1. + * + * Example: + * @code + * unsigned int *a, *b, *c; + * a = talloc(NULL, unsigned int); + * b = talloc(NULL, unsigned int); + * c = talloc(a, unsigned int); + * // b also serves as a parent of c. + * talloc_reference(b, c); + * talloc_unlink(b, c); + * @endcode + */ int talloc_unlink(const void *context, void *ptr); -const char *talloc_set_name(const void *ptr, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3); -void talloc_set_name_const(const void *ptr, const char *name); -void *talloc_named(const void *context, size_t size, - const char *fmt, ...) PRINTF_ATTRIBUTE(3,4); -void *talloc_named_const(const void *context, size_t size, const char *name); -const char *talloc_get_name(const void *ptr); -void *talloc_check_name(const void *ptr, const char *name); -void *_talloc_get_type_abort(const void *ptr, const char *name, const char *location); -void *talloc_parent(const void *ptr); -const char *talloc_parent_name(const void *ptr); -void *talloc_init(const char *fmt, ...) PRINTF_ATTRIBUTE(1,2); -int _talloc_free(void *ptr, const char *location); -void talloc_free_children(void *ptr); -void *_talloc_realloc(const void *context, void *ptr, size_t size, const char *name); -void *_talloc_steal_loc(const void *new_ctx, const void *ptr, const char *location); -void *talloc_reparent(const void *old_parent, const void *new_parent, const void *ptr); -void *_talloc_move(const void *new_ctx, const void *pptr); -size_t talloc_total_size(const void *ptr); -size_t talloc_total_blocks(const void *ptr); -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 *private_data), - void *private_data); -void talloc_report_depth_file(const void *ptr, int depth, int max_depth, FILE *f); -void talloc_report_full(const void *ptr, FILE *f); -void talloc_report(const void *ptr, FILE *f); -void talloc_enable_null_tracking(void); -void talloc_enable_null_tracking_no_autofree(void); -void talloc_disable_null_tracking(void); -void talloc_enable_leak_report(void); -void talloc_enable_leak_report_full(void); -void *_talloc_zero(const void *ctx, size_t size, const char *name); -void *_talloc_memdup(const void *t, const void *p, size_t size, const char *name); -void *_talloc_array(const void *ctx, size_t el_size, unsigned count, const char *name); -void *_talloc_zero_array(const void *ctx, size_t el_size, unsigned count, const char *name); -void *_talloc_realloc_array(const void *ctx, void *ptr, size_t el_size, unsigned count, const char *name); -void *talloc_realloc_fn(const void *context, void *ptr, size_t size); + +/** + * @brief Provide a talloc context that is freed at program exit. + * + * 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. + * + * @return A talloc context, NULL on error. + */ void *talloc_autofree_context(void); + +/** + * @brief Get the size of a talloc chunk. + * + * This function lets you know the amount of memory alloced so far by + * this context. It does NOT account for subcontext memory. + * This can be used to calculate the size of an array. + * + * @param[in] ctx The talloc chunk. + * + * @return The size of the talloc chunk. + */ size_t talloc_get_size(const void *ctx); -void *talloc_find_parent_byname(const void *ctx, const char *name); + +/** + * @brief Show the parentage of a context. + * + * @param[in] context The talloc context to look at. + * + * @param[in] file The output to use, a file, stdout or stderr. + */ void talloc_show_parents(const void *context, FILE *file); + +/** + * @brief Check if a context is parent of a talloc chunk. + * + * This checks if context is referenced in the talloc hierarchy above ptr. + * + * @param[in] context The assumed talloc context. + * + * @param[in] ptr The talloc chunk to check. + * + * @return Return 1 if this is the case, 0 if not. + */ int talloc_is_parent(const void *context, const void *ptr); +/** + * @brief Change the parent context of a talloc pointer. + * + * The 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. + * + * 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. + * + * @param[in] old_parent + * @param[in] new_parent + * @param[in] ptr + * + * @return Return the pointer you passed. It does not have any + * failure modes. + */ +void *talloc_reparent(const void *old_parent, const void *new_parent, const void *ptr); + +/* @} ******************************************************************/ + +/** + * @defgroup talloc_array The talloc array functions + * @ingroup talloc + * + * Talloc contains some handy helpers for handling Arrays conveniently + * + * @{ + */ + +#ifdef DOXYGEN +/** + * @brief Allocate an array. + * + * The macro is equivalent to: + * + * @code + * (type *)talloc_size(ctx, sizeof(type) * count); + * @endcode + * + * except that it provides integer overflow protection for the multiply, + * returning NULL if the multiply overflows. + * + * @param[in] ctx The talloc context to hang the result off. + * + * @param[in] type The type that we want to allocate. + * + * @param[in] count The number of 'type' elements you want to allocate. + * + * @return The allocated result, properly cast to 'type *', NULL on + * error. + * + * Example: + * @code + * unsigned int *a, *b; + * a = talloc_zero(NULL, unsigned int); + * b = talloc_array(a, unsigned int, 100); + * @endcode + * + * @see talloc() + * @see talloc_array_zero() + */ +void *talloc_array(const void *ctx, #type, unsigned count); +#else +#define talloc_array(ctx, type, count) (type *)_talloc_array(ctx, sizeof(type), count, #type) +void *_talloc_array(const void *ctx, size_t el_size, unsigned count, const char *name); +#endif + +#ifdef DOXYGEN +/** + * @brief Allocate an array. + * + * @param[in] ctx The talloc context to hang the result off. + * + * @param[in] size The size of an array element. + * + * @param[in] count The number of elements you want to allocate. + * + * @return The allocated result, NULL on error. + */ +void *talloc_array_size(const void *ctx, size_t size, unsigned count); +#else +#define talloc_array_size(ctx, size, count) _talloc_array(ctx, size, count, __location__) +#endif + +#ifdef DOXYGEN +/** + * @brief Allocate an array into a typed pointer. + * + * The 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. + * + * @param[in] ctx The talloc context to hang the result off. + * + * @param[in] ptr The pointer you want to assign the result to. + * + * @param[in] count The number of elements you want to allocate. + * + * @return The allocated memory chunk, properly casted. NULL on + * error. + */ +void *talloc_array_ptrtype(const void *ctx, const void *ptr, unsigned count); +#else +#define talloc_array_ptrtype(ctx, ptr, count) (_TALLOC_TYPEOF(ptr))talloc_array_size(ctx, sizeof(*(ptr)), count) +#endif + +#ifdef DOXYGEN +/** + * @brief Get the number of elements in a talloc'ed array. + * + * A talloc chunk carries its own size, so for talloc'ed arrays it is not + * necessary to store the number of elements explicitly. + * + * @param[in] ctx The allocated array. + * + * @return The number of elements in ctx. + */ +size_t talloc_array_length(const void *ctx); +#else +#define talloc_array_length(ctx) (talloc_get_size(ctx)/sizeof(*ctx)) +#endif + +#ifdef DOXYGEN +/** + * @brief Allocate a zero-initialized array + * + * @param[in] ctx The talloc context to hang the result off. + * + * @param[in] type The type that we want to allocate. + * + * @param[in] count The number of "type" elements you want to allocate. + * + * @return The allocated result casted to "type *", NULL on error. + * + * The talloc_zero_array() macro is equivalent to: + * + * @code + * ptr = talloc_array(ctx, type, count); + * if (ptr) memset(ptr, sizeof(type) * count); + * @endcode + */ +void *talloc_zero_array(const void *ctx, #type, unsigned count); +#else +#define talloc_zero_array(ctx, type, count) (type *)_talloc_zero_array(ctx, sizeof(type), count, #type) +void *_talloc_zero_array(const void *ctx, + size_t el_size, + unsigned count, + const char *name); +#endif + +#ifdef DOXYGEN +/** + * @brief Change the size of a talloc array. + * + * The macro changes the size of a talloc pointer. The 'count' argument is the + * number of elements of type 'type' that you want the resulting pointer to + * hold. + * + * talloc_realloc() has the following equivalences: + * + * @code + * talloc_realloc(ctx, NULL, type, 1) ==> talloc(ctx, type); + * talloc_realloc(ctx, NULL, type, N) ==> talloc_array(ctx, type, N); + * talloc_realloc(ctx, ptr, type, 0) ==> talloc_free(ptr); + * @endcode + * + * The "context" argument is only used if "ptr" is NULL, otherwise it is + * ignored. + * + * @param[in] ctx The parent context used if ptr is NULL. + * + * @param[in] ptr The chunk to be resized. + * + * @param[in] type The type of the array element inside ptr. + * + * @param[in] count The intended number of array elements. + * + * @return The new array, NULL on error. The call will fail either + * due to a lack of memory, or because the pointer has more + * than one parent (see talloc_reference()). + */ +void *talloc_realloc(const void *ctx, void *ptr, #type, size_t count); +#else +#define talloc_realloc(ctx, p, type, count) (type *)_talloc_realloc_array(ctx, p, sizeof(type), count, #type) +void *_talloc_realloc_array(const void *ctx, void *ptr, size_t el_size, unsigned count, const char *name); +#endif + +#if DOXYGEN +/** + * @brief Untyped realloc to change the size of a talloc array. + * + * The macro is useful when the type is not known so the typesafe + * talloc_realloc() cannot be used. + * + * @param[in] ctx The parent context used if 'ptr' is NULL. + * + * @param[in] ptr The chunk to be resized. + * + * @param[in] size The new chunk size. + * + * @return The new array, NULL on error. + */ +void *talloc_realloc_size(const void *ctx, void *ptr, size_t size); +#else +#define talloc_realloc_size(ctx, ptr, size) _talloc_realloc(ctx, ptr, size, __location__) +void *_talloc_realloc(const void *context, void *ptr, size_t size, const char *name); +#endif + +/** + * @brief Provide a function version of talloc_realloc_size. + * + * This is a non-macro version of talloc_realloc(), which is useful as + * libraries sometimes want a ralloc function pointer. A realloc() + * implementation encapsulates the functionality of malloc(), free() and + * realloc() in one call, which is why it is useful to be able to pass around + * a single function pointer. + * + * @param[in] context The parent context used if ptr is NULL. + * + * @param[in] ptr The chunk to be resized. + * + * @param[in] size The new chunk size. + * + * @return The new chunk, NULL on error. + */ +void *talloc_realloc_fn(const void *context, void *ptr, size_t size); + +/* @} ******************************************************************/ + +/** + * @defgroup talloc_string The talloc string functions. + * @ingroup talloc + * + * talloc string allocation and manipulation functions. + * @{ + */ + +/** + * @brief Duplicate a string into a talloc chunk. + * + * This function is equivalent to: + * + * @code + * ptr = talloc_size(ctx, strlen(p)+1); + * if (ptr) memcpy(ptr, p, strlen(p)+1); + * @endcode + * + * This functions sets the name of the new pointer to the passed + * string. This is equivalent to: + * + * @code + * talloc_set_name_const(ptr, ptr) + * @endcode + * + * @param[in] t The talloc context to hang the result off. + * + * @param[in] p The string you want to duplicate. + * + * @return The duplicated string, NULL on error. + */ char *talloc_strdup(const void *t, const char *p); char *talloc_strdup_append(char *s, const char *a); char *talloc_strdup_append_buffer(char *s, const char *a); +/** + * @brief Duplicate a length-limited string into a talloc chunk. + * + * This function is the talloc equivalent of the C library function strndup(3). + * + * This functions sets the name of the new pointer to the passed string. This is + * equivalent to: + * + * @code + * talloc_set_name_const(ptr, ptr) + * @endcode + * + * @param[in] t The talloc context to hang the result off. + * + * @param[in] p The string you want to duplicate. + * + * @param[in] n The maximum string length to duplicate. + * + * @return The duplicated string, NULL on error. + */ char *talloc_strndup(const void *t, const char *p, size_t n); char *talloc_strndup_append(char *s, const char *a, size_t n); char *talloc_strndup_append_buffer(char *s, const char *a, size_t n); +/** + * @brief Format a string given a va_list. + * + * This function is the talloc equivalent of the C library function + * vasprintf(3). + * + * This functions sets the name of the new pointer to the new string. This is + * equivalent to: + * + * @code + * talloc_set_name_const(ptr, ptr) + * @endcode + * + * @param[in] t The talloc context to hang the result off. + * + * @param[in] fmt The format string. + * + * @param[in] ap The parameters used to fill fmt. + * + * @return The formatted string, NULL on error. + */ char *talloc_vasprintf(const void *t, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0); char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0); char *talloc_vasprintf_append_buffer(char *s, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0); +/** + * @brief Format a string. + * + * This function is the talloc equivalent of the C library function asprintf(3). + * + * This functions sets the name of the new pointer to the new string. This is + * equivalent to: + * + * @code + * talloc_set_name_const(ptr, ptr) + * @endcode + * + * @param[in] t The talloc context to hang the result off. + * + * @param[in] fmt The format string. + * + * @param[in] ... The parameters used to fill fmt. + * + * @return The formatted string, NULL on error. + */ char *talloc_asprintf(const void *t, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3); + +/** + * @brief Append a formatted string to another string. + * + * This function appends the given formatted string to the given string. Use + * this varient when the string in the current talloc buffer may have been + * truncated in length. + * + * This functions sets the name of the new pointer to the new + * string. This is equivalent to: + * + * @code + * talloc_set_name_const(ptr, ptr) + * @endcode + * + * @param[in] s The string to append to. + * + * @param[in] fmt The format string. + * + * @param[in] ... The parameters used to fill fmt. + * + * @return The formatted string, NULL on error. + */ char *talloc_asprintf_append(char *s, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3); + +/** + * @brief Append a formatted string to another string. + * + * @param[in] s The string to append to + * + * @param[in] fmt The format string. + * + * @param[in] ... The parameters used to fill fmt. + * + * @return The formatted string, NULL on error. + */ char *talloc_asprintf_append_buffer(char *s, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3); +/* @} ******************************************************************/ + +/** + * @defgroup talloc_debug The talloc debugging support functions + * @ingroup talloc + * + * To aid memory debugging, talloc contains routines to inspect the currently + * allocated memory hierarchy. + * + * @{ + */ + +/** + * @brief Walk a complete talloc hierarchy. + * + * 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 + * is_ref = 1 and the pointer that is referenced. + * + * 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. + * + * The recursion is stopped when depth >= max_depth. + * max_depth = -1 means only stop at leaf nodes. + * + * @param[in] ptr The talloc chunk. + * + * @param[in] depth Internal parameter to control recursion. Call with 0. + * + * @param[in] max_depth Maximum recursion level. + * + * @param[in] callback Function to be called on every chunk. + * + * @param[in] private_data Private pointer passed to callback. + */ +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 *private_data), + void *private_data); + +/** + * @brief Print a talloc hierarchy. + * + * This provides a more flexible reports than talloc_report(). It + * will let you specify the depth and max_depth. + * + * @param[in] ptr The talloc chunk. + * + * @param[in] depth Internal parameter to control recursion. Call with 0. + * + * @param[in] max_depth Maximum recursion level. + * + * @param[in] f The file handle to print to. + */ +void talloc_report_depth_file(const void *ptr, int depth, int max_depth, FILE *f); + +/** + * @brief Print a summary report of all memory used by ptr. + * + * This provides a more detailed report than talloc_report(). It will + * recursively print the ensire tree of memory referenced by the + * pointer. References in the tree are shown by giving the name of the + * pointer that is referenced. + * + * 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. + * + * @param[in] ptr The talloc chunk. + * + * @param[in] f The file handle to print to. + * + * Example: + * @code + * unsigned int *a, *b; + * a = talloc(NULL, unsigned int); + * b = talloc(a, unsigned int); + * fprintf(stderr, "Dumping memory tree for a:\n"); + * talloc_report_full(a, stderr); + * @endcode + * + * @see talloc_report() + */ +void talloc_report_full(const void *ptr, FILE *f); + +/** + * @brief Print a summary report of all memory used by ptr. + * + * This function prints a summary report of all memory used by ptr. One line of + * report is printed for each immediate child of ptr, showing the total memory + * and number of blocks used by that child. + * + * 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. + * + * @param[in] ptr The talloc chunk. + * + * @param[in] f The file handle to print to. + * + * Example: + * @code + * unsigned int *a, *b; + * a = talloc(NULL, unsigned int); + * b = talloc(a, unsigned int); + * fprintf(stderr, "Summary of memory tree for a:\n"); + * talloc_report(a, stderr); + * @endcode + * + * @see talloc_report_full() + */ +void talloc_report(const void *ptr, FILE *f); + +/** + * @brief Enable tracking the use of NULL memory contexts. + * + * This enables tracking of the NULL memory context without enabling leak + * reporting on exit. Useful for when you want to do your own leak + * reporting call via talloc_report_null_full(); + */ +void talloc_enable_null_tracking(void); + +/** + * @brief Enable tracking the use of NULL memory contexts. + * + * This enables tracking of the NULL memory context without enabling leak + * reporting on exit. Useful for when you want to do your own leak + * reporting call via talloc_report_null_full(); + */ +void talloc_enable_null_tracking_no_autofree(void); + +/** + * @brief Disable tracking of the NULL memory context. + * + * This disables tracking of the NULL memory context. + */ +void talloc_disable_null_tracking(void); + +/** + * @brief Enable leak report when a program exits. + * + * 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. + * + * 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't call this function first then passing + * NULL to talloc_report() or talloc_report_full() won't give you the + * full tree printout. + * + * Here is a typical talloc report: + * + * @code + * talloc report on 'null_context' (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 + * @endcode + */ +void talloc_enable_leak_report(void); + +/** + * @brief Enable full leak report when a program exits. + * + * 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. + * + * 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't call this function first then passing + * NULL to talloc_report() or talloc_report_full() won't give you the + * full tree printout. + * + * Here is a typical full report: + * + * @code + * full talloc report on 'root' (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) + * @endcode + */ +void talloc_enable_leak_report_full(void); + +/* @} ******************************************************************/ + void talloc_set_abort_fn(void (*abort_fn)(const char *reason)); void talloc_set_log_fn(void (*log_fn)(const char *message)); void talloc_set_log_stderr(void); +#if TALLOC_DEPRECATED +#define talloc_zero_p(ctx, type) talloc_zero(ctx, type) +#define talloc_p(ctx, type) talloc(ctx, type) +#define talloc_array_p(ctx, type, count) talloc_array(ctx, type, count) +#define talloc_realloc_p(ctx, p, type, count) talloc_realloc(ctx, p, type, count) +#define talloc_destroy(ctx) talloc_free(ctx) +#define talloc_append_string(c, s, a) (s?talloc_strdup_append(s,a):talloc_strdup(c, a)) +#endif + #endif |