#ifndef _TALLOC_H_
#define _TALLOC_H_
/*
Unix SMB/CIFS implementation.
Samba temporary memory allocation functions
Copyright (C) Andrew Tridgell 2004-2005
Copyright (C) Stefan Metzmacher 2006
** NOTE! The following LGPL license applies to the talloc
** library. This does NOT imply that all of Samba is released
** under the LGPL
This library 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.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see .
*/
#include
#include
#include
/**
* @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.
*
* @{
*/
#define TALLOC_VERSION_MAJOR 2
#define TALLOC_VERSION_MINOR 0
int talloc_version_major(void);
int talloc_version_minor(void);
/**
* @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;
/*
this uses a little trick to allow __LINE__ to be stringified
*/
#ifndef __location__
#define __TALLOC_STRING_LINE1__(s) #s
#define __TALLOC_STRING_LINE2__(s) __TALLOC_STRING_LINE1__(s)
#define __TALLOC_STRING_LINE3__ __TALLOC_STRING_LINE2__(__LINE__)
#define __location__ __FILE__ ":" __TALLOC_STRING_LINE3__
#endif
#ifndef TALLOC_DEPRECATED
#define TALLOC_DEPRECATED 0
#endif
#ifndef PRINTF_ATTRIBUTE
#if (__GNUC__ >= 3)
/** Use gcc attribute to check printf fns. a1 is the 1-based index of
* the parameter containing the format, and a2 the index of the first
* argument. Note that some gcc 2.x versions don't handle this
* properly **/
#define PRINTF_ATTRIBUTE(a1, a2) __attribute__ ((format (__printf__, a1, a2)))
#else
#define PRINTF_ATTRIBUTE(a1, a2)
#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);
#ifdef 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)
#define _TALLOC_TYPEOF(ptr) __typeof__(ptr)
#define talloc_set_destructor(ptr, function) \
do { \
int (*_talloc_destructor_fn)(_TALLOC_TYPEOF(ptr)) = (function); \
_talloc_set_destructor((ptr), (int (*)(void *))_talloc_destructor_fn); \
} while(0)
/* 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 /* __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 /* __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 */
/**
* @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
/**
* @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
/**
* @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);
/**
* @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)
#endif
#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 same 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);
#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)
/* @} ******************************************************************/
/**
* \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);
/**
* @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);
/**
* @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
#ifdef 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