/*
  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg 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 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg 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 FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 /**

  * @file

  * @ingroup lavu_mem
  * Memory handling functions

  */
 

 #ifndef AVUTIL_MEM_H
 #define AVUTIL_MEM_H

 #include <limits.h>

 #include <stdint.h>

 #include "attributes.h"

 #include "error.h"

 #include "avutil.h"

 /**
  * @addtogroup lavu_mem

  * Utilities for manipulating memory.
  *
  * FFmpeg has several applications of memory that are not required of a typical
  * program. For example, the computing-heavy components like video decoding and
  * encoding can be sped up significantly through the use of aligned memory.
  *
  * However, for each of FFmpeg's applications of memory, there might not be a
  * recognized or standardized API for that specific use. Memory alignment, for
  * instance, varies wildly depending on operating systems, architectures, and
  * compilers. Hence, this component of @ref libavutil is created to make
  * dealing with memory consistently possible on all platforms.
  *
  * @{
  *
  * @defgroup lavu_mem_macros Alignment Macros
  * Helper macros for declaring aligned variables.

  * @{
  */
 

 /**
  * @def DECLARE_ALIGNED(n,t,v)
  * Declare a variable that is aligned in memory.
  *
  * @code{.c}
  * DECLARE_ALIGNED(16, uint16_t, aligned_int) = 42;
  * DECLARE_ALIGNED(32, uint8_t, aligned_array)[128];
  *
  * // The default-alignment equivalent would be
  * uint16_t aligned_int = 42;
  * uint8_t aligned_array[128];
  * @endcode
  *
  * @param n Minimum alignment in bytes
  * @param t Type of the variable (or array element)
  * @param v Name of the variable
  */
 
 /**

  * @def DECLARE_ASM_ALIGNED(n,t,v)
  * Declare an aligned variable appropriate for use in inline assembly code.
  *
  * @code{.c}
  * DECLARE_ASM_ALIGNED(16, uint64_t, pw_08) = UINT64_C(0x0008000800080008);
  * @endcode
  *
  * @param n Minimum alignment in bytes
  * @param t Type of the variable (or array element)
  * @param v Name of the variable
  */
 
 /**

  * @def DECLARE_ASM_CONST(n,t,v)
  * Declare a static constant aligned variable appropriate for use in inline
  * assembly code.
  *
  * @code{.c}
  * DECLARE_ASM_CONST(16, uint64_t, pw_08) = UINT64_C(0x0008000800080008);
  * @endcode
  *
  * @param n Minimum alignment in bytes
  * @param t Type of the variable (or array element)
  * @param v Name of the variable
  */

 #if defined(__INTEL_COMPILER) && __INTEL_COMPILER < 1110 || defined(__SUNPRO_C)

     #define DECLARE_ALIGNED(n,t,v)      t __attribute__ ((aligned (n))) v

     #define DECLARE_ASM_ALIGNED(n,t,v)  t __attribute__ ((aligned (n))) v

     #define DECLARE_ASM_CONST(n,t,v)    const t __attribute__ ((aligned (n))) v

 #elif defined(__DJGPP__)
     #define DECLARE_ALIGNED(n,t,v)      t __attribute__ ((aligned (FFMIN(n, 16)))) v
     #define DECLARE_ASM_CONST(n,t,v)    static const t av_used __attribute__ ((aligned (FFMIN(n, 16)))) v

 #elif defined(__GNUC__) || defined(__clang__)

     #define DECLARE_ALIGNED(n,t,v)      t __attribute__ ((aligned (n))) v

     #define DECLARE_ASM_ALIGNED(n,t,v)  t av_used __attribute__ ((aligned (n))) v

     #define DECLARE_ASM_CONST(n,t,v)    static const t av_used __attribute__ ((aligned (n))) v

 #elif defined(_MSC_VER)
     #define DECLARE_ALIGNED(n,t,v)      __declspec(align(n)) t v

     #define DECLARE_ASM_ALIGNED(n,t,v)  __declspec(align(n)) t v

     #define DECLARE_ASM_CONST(n,t,v)    __declspec(align(n)) static const t v
 #else
     #define DECLARE_ALIGNED(n,t,v)      t v

     #define DECLARE_ASM_ALIGNED(n,t,v)  t v

     #define DECLARE_ASM_CONST(n,t,v)    static const t v
 #endif
 

 /**
  * @}
  */
 
 /**
  * @defgroup lavu_mem_attrs Function Attributes
  * Function attributes applicable to memory handling functions.
  *
  * These function attributes can help compilers emit more useful warnings, or
  * generate better code.
  * @{
  */
 
 /**
  * @def av_malloc_attrib
  * Function attribute denoting a malloc-like function.
  *
  * @see <a href="https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-g_t_0040code_007bmalloc_007d-function-attribute-3251">Function attribute `malloc` in GCC's documentation</a>
  */
 

 #if AV_GCC_VERSION_AT_LEAST(3,1)

     #define av_malloc_attrib __attribute__((__malloc__))
 #else
     #define av_malloc_attrib
 #endif
 

 /**
  * @def av_alloc_size(...)
  * Function attribute used on a function that allocates memory, whose size is
  * given by the specified parameter(s).
  *
  * @code{.c}
  * void *av_malloc(size_t size) av_alloc_size(1);
  * void *av_calloc(size_t nmemb, size_t size) av_alloc_size(1, 2);
  * @endcode
  *
  * @param ... One or two parameter indexes, separated by a comma
  *
  * @see <a href="https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-g_t_0040code_007balloc_005fsize_007d-function-attribute-3220">Function attribute `alloc_size` in GCC's documentation</a>
  */
 

 #if AV_GCC_VERSION_AT_LEAST(4,3)

     #define av_alloc_size(...) __attribute__((alloc_size(__VA_ARGS__)))

 #else

     #define av_alloc_size(...)

 #endif
 

 /**

  * @}
  */
 
 /**
  * @defgroup lavu_mem_funcs Heap Management
  * Functions responsible for allocating, freeing, and copying memory.
  *
  * All memory allocation functions have a built-in upper limit of `INT_MAX`
  * bytes. This may be changed with av_max_alloc(), although exercise extreme
  * caution when doing so.
  *
  * @{
  */
 
 /**
  * Allocate a memory block with alignment suitable for all memory accesses
  * (including vectors if available on the CPU).
  *
  * @param size Size in bytes for the memory block to be allocated
  * @return Pointer to the allocated block, or `NULL` if the block cannot
  *         be allocated

  * @see av_mallocz()

  */

 void *av_malloc(size_t size) av_malloc_attrib av_alloc_size(1);

 
 /**

  * Allocate a memory block with alignment suitable for all memory accesses
  * (including vectors if available on the CPU) and zero all the bytes of the
  * block.
  *
  * @param size Size in bytes for the memory block to be allocated
  * @return Pointer to the allocated block, or `NULL` if it cannot be allocated

  * @see av_malloc()
  */
 void *av_mallocz(size_t size) av_malloc_attrib av_alloc_size(1);
 
 /**

  * Allocate a memory block for an array with av_malloc().
  *
  * The allocated memory will have size `size * nmemb` bytes.
  *
  * @param nmemb Number of element
  * @param size  Size of a single element
  * @return Pointer to the allocated block, or `NULL` if the block cannot
  *         be allocated

  * @see av_malloc()
  */

 av_alloc_size(1, 2) void *av_malloc_array(size_t nmemb, size_t size);

 
 /**

  * Allocate a memory block for an array with av_mallocz().
  *
  * The allocated memory will have size `size * nmemb` bytes.
  *

  * @param nmemb Number of elements

  * @param size  Size of the single element
  * @return Pointer to the allocated block, or `NULL` if the block cannot
  *         be allocated
  *

  * @see av_mallocz()
  * @see av_malloc_array()
  */

 av_alloc_size(1, 2) void *av_mallocz_array(size_t nmemb, size_t size);

 
 /**

  * Non-inlined equivalent of av_mallocz_array().
  *
  * Created for symmetry with the calloc() C function.

  */
 void *av_calloc(size_t nmemb, size_t size) av_malloc_attrib;
 
 /**

  * Allocate, reallocate, or free a block of memory.
  *
  * If `ptr` is `NULL` and `size` > 0, allocate a new block. If `size` is
  * zero, free the memory block pointed to by `ptr`. Otherwise, expand or
  * shrink that block of memory according to `size`.
  *
  * @param ptr  Pointer to a memory block already allocated with
  *             av_realloc() or `NULL`

  * @param size Size in bytes of the memory block to be allocated or

  *             reallocated
  *
  * @return Pointer to a newly-reallocated block or `NULL` if the block
  *         cannot be reallocated or the function is used to free the memory block
  *
  * @warning Unlike av_malloc(), the returned pointer is not guaranteed to be
  *          correctly aligned.

  * @see av_fast_realloc()

  * @see av_reallocp()

  */

 void *av_realloc(void *ptr, size_t size) av_alloc_size(2);

 
 /**

  * Allocate, reallocate, or free a block of memory through a pointer to a
  * pointer.
  *
  * If `*ptr` is `NULL` and `size` > 0, allocate a new block. If `size` is
  * zero, free the memory block pointed to by `*ptr`. Otherwise, expand or
  * shrink that block of memory according to `size`.
  *
  * @param[in,out] ptr  Pointer to a pointer to a memory block already allocated
  *                     with av_realloc(), or a pointer to `NULL`. The pointer
  *                     is updated on success, or freed on failure.
  * @param[in]     size Size in bytes for the memory block to be allocated or
  *                     reallocated
  *
  * @return Zero on success, an AVERROR error code on failure
  *
  * @warning Unlike av_malloc(), the allocated memory is not guaranteed to be
  *          correctly aligned.

  */

 av_warn_unused_result

 int av_reallocp(void *ptr, size_t size);
 
 /**

  * Allocate, reallocate, or free a block of memory.
  *
  * This function does the same thing as av_realloc(), except:
  * - It takes two size arguments and allocates `nelem * elsize` bytes,
  *   after checking the result of the multiplication for integer overflow.

  * - It frees the input block in case of failure, thus avoiding the memory

  *   leak with the classic
  *   @code{.c}
  *   buf = realloc(buf);
  *   if (!buf)
  *       return -1;
  *   @endcode
  *   pattern.

  */
 void *av_realloc_f(void *ptr, size_t nelem, size_t elsize);
 
 /**

  * Allocate, reallocate, or free an array.
  *
  * If `ptr` is `NULL` and `nmemb` > 0, allocate a new block. If
  * `nmemb` is zero, free the memory block pointed to by `ptr`.
  *
  * @param ptr   Pointer to a memory block already allocated with
  *              av_realloc() or `NULL`
  * @param nmemb Number of elements in the array
  * @param size  Size of the single element of the array
  *

  * @return Pointer to a newly-reallocated block or NULL if the block

  *         cannot be reallocated or the function is used to free the memory block
  *
  * @warning Unlike av_malloc(), the allocated memory is not guaranteed to be
  *          correctly aligned.
  * @see av_reallocp_array()

  */
 av_alloc_size(2, 3) void *av_realloc_array(void *ptr, size_t nmemb, size_t size);
 
 /**

  * Allocate, reallocate, or free an array through a pointer to a pointer.
  *
  * If `*ptr` is `NULL` and `nmemb` > 0, allocate a new block. If `nmemb` is
  * zero, free the memory block pointed to by `*ptr`.
  *
  * @param[in,out] ptr   Pointer to a pointer to a memory block already
  *                      allocated with av_realloc(), or a pointer to `NULL`.
  *                      The pointer is updated on success, or freed on failure.
  * @param[in]     nmemb Number of elements
  * @param[in]     size  Size of the single element
  *
  * @return Zero on success, an AVERROR error code on failure
  *
  * @warning Unlike av_malloc(), the allocated memory is not guaranteed to be
  *          correctly aligned.

  */
 av_alloc_size(2, 3) int av_reallocp_array(void *ptr, size_t nmemb, size_t size);
 
 /**

  * Reallocate the given buffer if it is not large enough, otherwise do nothing.
  *
  * If the given buffer is `NULL`, then a new uninitialized buffer is allocated.
  *
  * If the given buffer is not large enough, and reallocation fails, `NULL` is
  * returned and `*size` is set to 0, but the original buffer is not changed or
  * freed.
  *
  * A typical use pattern follows:
  *
  * @code{.c}
  * uint8_t *buf = ...;
  * uint8_t *new_buf = av_fast_realloc(buf, &current_size, size_needed);
  * if (!new_buf) {
  *     // Allocation failed; clean up original buffer
  *     av_freep(&buf);
  *     return AVERROR(ENOMEM);
  * }
  * @endcode

  *

  * @param[in,out] ptr      Already allocated buffer, or `NULL`
  * @param[in,out] size     Pointer to current size of buffer `ptr`. `*size` is
  *                         changed to `min_size` in case of success or 0 in
  *                         case of failure
  * @param[in]     min_size New size of buffer `ptr`
  * @return `ptr` if the buffer is large enough, a pointer to newly reallocated
  *         buffer if the buffer was not large enough, or `NULL` in case of
  *         error
  * @see av_realloc()
  * @see av_fast_malloc()

  */
 void *av_fast_realloc(void *ptr, unsigned int *size, size_t min_size);
 
 /**
  * Allocate a buffer, reusing the given one if large enough.
  *

  * Contrary to av_fast_realloc(), the current buffer contents might not be
  * preserved and on error the old buffer is freed, thus no special handling to
  * avoid memleaks is necessary.

  *

  * `*ptr` is allowed to be `NULL`, in which case allocation always happens if
  * `size_needed` is greater than 0.
  *
  * @code{.c}
  * uint8_t *buf = ...;
  * av_fast_malloc(&buf, &current_size, size_needed);
  * if (!buf) {
  *     // Allocation failed; buf already freed
  *     return AVERROR(ENOMEM);
  * }
  * @endcode
  *
  * @param[in,out] ptr      Pointer to pointer to an already allocated buffer.
  *                         `*ptr` will be overwritten with pointer to new
  *                         buffer on success or `NULL` on failure
  * @param[in,out] size     Pointer to current size of buffer `*ptr`. `*size` is
  *                         changed to `min_size` in case of success or 0 in
  *                         case of failure
  * @param[in]     min_size New size of buffer `*ptr`
  * @see av_realloc()
  * @see av_fast_mallocz()

  */
 void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size);
 
 /**

  * Allocate and clear a buffer, reusing the given one if large enough.
  *
  * Like av_fast_malloc(), but all newly allocated space is initially cleared.
  * Reused buffer is not cleared.

  *

  * `*ptr` is allowed to be `NULL`, in which case allocation always happens if
  * `size_needed` is greater than 0.

  *

  * @param[in,out] ptr      Pointer to pointer to an already allocated buffer.
  *                         `*ptr` will be overwritten with pointer to new
  *                         buffer on success or `NULL` on failure
  * @param[in,out] size     Pointer to current size of buffer `*ptr`. `*size` is
  *                         changed to `min_size` in case of success or 0 in
  *                         case of failure
  * @param[in]     min_size New size of buffer `*ptr`
  * @see av_fast_malloc()

  */
 void av_fast_mallocz(void *ptr, unsigned int *size, size_t min_size);
 
 /**

  * Free a memory block which has been allocated with a function of av_malloc()
  * or av_realloc() family.
  *

  * @param ptr Pointer to the memory block which should be freed.

  *
  * @note `ptr = NULL` is explicitly allowed.
  * @note It is recommended that you use av_freep() instead, to prevent leaving
  *       behind dangling pointers.

  * @see av_freep()

  */
 void av_free(void *ptr);
 

 /**

  * Free a memory block which has been allocated with a function of av_malloc()
  * or av_realloc() family, and set the pointer pointing to it to `NULL`.
  *
  * @code{.c}
  * uint8_t *buf = av_malloc(16);
  * av_free(buf);
  * // buf now contains a dangling pointer to freed memory, and accidental
  * // dereference of buf will result in a use-after-free, which may be a
  * // security risk.
  *
  * uint8_t *buf = av_malloc(16);
  * av_freep(&buf);
  * // buf is now NULL, and accidental dereference will only result in a
  * // NULL-pointer dereference.
  * @endcode
  *
  * @param ptr Pointer to the pointer to the memory block which should be freed
  * @note `*ptr = NULL` is safe and leads to no action.

  * @see av_free()

  */

 void av_freep(void *ptr);

 
 /**

  * Duplicate a string.
  *
  * @param s String to be duplicated

  * @return Pointer to a newly-allocated string containing a

  *         copy of `s` or `NULL` if the string cannot be allocated
  * @see av_strndup()

  */

 char *av_strdup(const char *s) av_malloc_attrib;

 
 /**

  * Duplicate a substring of a string.
  *
  * @param s   String to be duplicated
  * @param len Maximum length of the resulting string (not counting the
  *            terminating byte)

  * @return Pointer to a newly-allocated string containing a

  *         substring of `s` or `NULL` if the string cannot be allocated

  */
 char *av_strndup(const char *s, size_t len) av_malloc_attrib;
 
 /**

  * Duplicate a buffer with av_malloc().
  *
  * @param p    Buffer to be duplicated
  * @param size Size in bytes of the buffer copied

  * @return Pointer to a newly allocated buffer containing a

  *         copy of `p` or `NULL` if the buffer cannot be allocated

  */
 void *av_memdup(const void *p, size_t size);
 
 /**

  * Overlapping memcpy() implementation.
  *
  * @param dst  Destination buffer
  * @param back Number of bytes back to start copying (i.e. the initial size of
  *             the overlapping window); must be > 0
  * @param cnt  Number of bytes to copy; must be >= 0

  *

  * @note `cnt > back` is valid, this will copy the bytes we just copied,
  *       thus creating a repeating pattern with a period length of `back`.

  */

 void av_memcpy_backptr(uint8_t *dst, int back, int cnt);

 /**

  * @}
  */
 
 /**
  * @defgroup lavu_mem_dynarray Dynamic Array
  *
  * Utilities to make an array grow when needed.
  *
  * Sometimes, the programmer would want to have an array that can grow when
  * needed. The libavutil dynamic array utilities fill that need.
  *
  * libavutil supports two systems of appending elements onto a dynamically
  * allocated array, the first one storing the pointer to the value in the
  * array, and the second storing the value directly. In both systems, the
  * caller is responsible for maintaining a variable containing the length of
  * the array, as well as freeing of the array after use.
  *
  * The first system stores pointers to values in a block of dynamically
  * allocated memory. Since only pointers are stored, the function does not need
  * to know the size of the type. Both av_dynarray_add() and
  * av_dynarray_add_nofree() implement this system.
  *
  * @code
  * type **array = NULL; //< an array of pointers to values
  * int    nb    = 0;    //< a variable to keep track of the length of the array
  *
  * type to_be_added  = ...;
  * type to_be_added2 = ...;
  *
  * av_dynarray_add(&array, &nb, &to_be_added);
  * if (nb == 0)
  *     return AVERROR(ENOMEM);
  *
  * av_dynarray_add(&array, &nb, &to_be_added2);
  * if (nb == 0)
  *     return AVERROR(ENOMEM);
  *
  * // Now:
  * //  nb           == 2
  * // &to_be_added  == array[0]
  * // &to_be_added2 == array[1]
  *
  * av_freep(&array);
  * @endcode
  *
  * The second system stores the value directly in a block of memory. As a
  * result, the function has to know the size of the type. av_dynarray2_add()
  * implements this mechanism.
  *
  * @code
  * type *array = NULL; //< an array of values
  * int   nb    = 0;    //< a variable to keep track of the length of the array
  *
  * type to_be_added  = ...;
  * type to_be_added2 = ...;
  *
  * type *addr = av_dynarray2_add((void **)&array, &nb, sizeof(*array), NULL);
  * if (!addr)
  *     return AVERROR(ENOMEM);
  * memcpy(addr, &to_be_added, sizeof(to_be_added));
  *
  * // Shortcut of the above.
  * type *addr = av_dynarray2_add((void **)&array, &nb, sizeof(*array),
  *                               (const void *)&to_be_added2);
  * if (!addr)
  *     return AVERROR(ENOMEM);
  *
  * // Now:
  * //  nb           == 2
  * //  to_be_added  == array[0]
  * //  to_be_added2 == array[1]
  *
  * av_freep(&array);
  * @endcode
  *
  * @{
  */
 
 /**
  * Add the pointer to an element to a dynamic array.

  *

  * The array to grow is supposed to be an array of pointers to
  * structures, and the element to add must be a pointer to an already
  * allocated structure.
  *

  * The array is reallocated when its size reaches powers of 2.

  * Therefore, the amortized cost of adding an element is constant.
  *
  * In case of success, the pointer to the array is updated in order to

  * point to the new grown array, and the number pointed to by `nb_ptr`

  * is incremented.

  * In case of failure, the array is freed, `*tab_ptr` is set to `NULL` and
  * `*nb_ptr` is set to 0.

  *

  * @param[in,out] tab_ptr Pointer to the array to grow
  * @param[in,out] nb_ptr  Pointer to the number of elements in the array
  * @param[in]     elem    Element to add

  * @see av_dynarray_add_nofree(), av_dynarray2_add()

  */
 void av_dynarray_add(void *tab_ptr, int *nb_ptr, void *elem);
 

 /**

  * Add an element to a dynamic array.
  *
  * Function has the same functionality as av_dynarray_add(),
  * but it doesn't free memory on fails. It returns error code
  * instead and leave current buffer untouched.
  *

  * @return >=0 on success, negative otherwise

  * @see av_dynarray_add(), av_dynarray2_add()
  */

 av_warn_unused_result

 int av_dynarray_add_nofree(void *tab_ptr, int *nb_ptr, void *elem);
 
 /**

  * Add an element of size `elem_size` to a dynamic array.

  *
  * The array is reallocated when its number of elements reaches powers of 2.
  * Therefore, the amortized cost of adding an element is constant.
  *
  * In case of success, the pointer to the array is updated in order to

  * point to the new grown array, and the number pointed to by `nb_ptr`

  * is incremented.

  * In case of failure, the array is freed, `*tab_ptr` is set to `NULL` and
  * `*nb_ptr` is set to 0.
  *
  * @param[in,out] tab_ptr   Pointer to the array to grow
  * @param[in,out] nb_ptr    Pointer to the number of elements in the array
  * @param[in]     elem_size Size in bytes of an element in the array
  * @param[in]     elem_data Pointer to the data of the element to add. If
  *                          `NULL`, the space of the newly added element is
  *                          allocated but left uninitialized.
  *
  * @return Pointer to the data of the element to copy in the newly allocated
  *         space

  * @see av_dynarray_add(), av_dynarray_add_nofree()

  */
 void *av_dynarray2_add(void **tab_ptr, int *nb_ptr, size_t elem_size,
                        const uint8_t *elem_data);
 
 /**

  * @}
  */
 
 /**
  * @defgroup lavu_mem_misc Miscellaneous Functions
  *
  * Other functions related to memory allocation.
  *
  * @{
  */
 
 /**
  * Multiply two `size_t` values checking for overflow.
  *
  * @param[in]  a,b Operands of multiplication
  * @param[out] r   Pointer to the result of the operation
  * @return 0 on success, AVERROR(EINVAL) on overflow

  */
 static inline int av_size_mult(size_t a, size_t b, size_t *r)
 {
     size_t t = a * b;

     /* Hack inspired from glibc: don't try the division if nelem and elsize
      * are both less than sqrt(SIZE_MAX). */

     if ((a | b) >= ((size_t)1 << (sizeof(size_t) * 4)) && a && t / a != b)
         return AVERROR(EINVAL);
     *r = t;
     return 0;
 }
 

 /**

  * Set the maximum size that may be allocated in one block.
  *
  * The value specified with this function is effective for all libavutil's @ref
  * lavu_mem_funcs "heap management functions."
  *
  * By default, the max value is defined as `INT_MAX`.
  *
  * @param max Value to be set as the new maximum size
  *
  * @warning Exercise extreme caution when using this function. Don't touch
  *          this if you do not understand the full consequence of doing so.

  */
 void av_max_alloc(size_t max);
 
 /**

  * @}

  * @}

  */
 

 #endif /* AVUTIL_MEM_H */