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Diffstat (limited to 'media/ffvpx/libavutil/mem.h')
| -rw-r--r-- | media/ffvpx/libavutil/mem.h | 406 |
1 files changed, 406 insertions, 0 deletions
diff --git a/media/ffvpx/libavutil/mem.h b/media/ffvpx/libavutil/mem.h new file mode 100644 index 000000000..d25b3229b --- /dev/null +++ b/media/ffvpx/libavutil/mem.h @@ -0,0 +1,406 @@ +/* + * 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 + * 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 + * @{ + */ + + +#if defined(__INTEL_COMPILER) && __INTEL_COMPILER < 1110 || defined(__SUNPRO_C) + #define DECLARE_ALIGNED(n,t,v) t __attribute__ ((aligned (n))) v + #define DECLARE_ASM_CONST(n,t,v) const t __attribute__ ((aligned (n))) v +#elif defined(__TI_COMPILER_VERSION__) + #define DECLARE_ALIGNED(n,t,v) \ + AV_PRAGMA(DATA_ALIGN(v,n)) \ + t __attribute__((aligned(n))) v + #define DECLARE_ASM_CONST(n,t,v) \ + AV_PRAGMA(DATA_ALIGN(v,n)) \ + static const t __attribute__((aligned(n))) v +#elif defined(__GNUC__) + #define DECLARE_ALIGNED(n,t,v) t __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_CONST(n,t,v) __declspec(align(n)) static const t v +#else + #define DECLARE_ALIGNED(n,t,v) t v + #define DECLARE_ASM_CONST(n,t,v) static const t v +#endif + +#if AV_GCC_VERSION_AT_LEAST(3,1) + #define av_malloc_attrib __attribute__((__malloc__)) +#else + #define av_malloc_attrib +#endif + +#if AV_GCC_VERSION_AT_LEAST(4,3) + #define av_alloc_size(...) __attribute__((alloc_size(__VA_ARGS__))) +#else + #define av_alloc_size(...) +#endif + +/** + * Allocate a block of size bytes 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, 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 block of size * nmemb bytes with av_malloc(). + * @param nmemb Number of elements + * @param size Size of the single element + * @return Pointer to the allocated block, NULL if the block cannot + * be allocated. + * @see av_malloc() + */ +av_alloc_size(1, 2) static inline void *av_malloc_array(size_t nmemb, size_t size) +{ + if (!size || nmemb >= INT_MAX / size) + return NULL; + return av_malloc(nmemb * size); +} + +/** + * Allocate or reallocate 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. + * @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 Pointers originating from the av_malloc() family of functions must + * not be passed to av_realloc(). The former can be implemented using + * memalign() (or other functions), and there is no guarantee that + * pointers from such functions can be passed to realloc() at all. + * The situation is undefined according to POSIX and may crash with + * some libc implementations. + * @see av_fast_realloc() + */ +void *av_realloc(void *ptr, size_t size) av_alloc_size(2); + +/** + * Allocate or reallocate a block of memory. + * This function does the same thing as av_realloc, except: + * - It takes two arguments and checks 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 "buf = realloc(buf); if (!buf) return -1;". + */ +void *av_realloc_f(void *ptr, size_t nelem, size_t elsize); + +/** + * Allocate or reallocate 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. + * @param ptr Pointer to a pointer to a memory block already allocated + * with av_realloc(), or pointer to a pointer to NULL. + * The pointer is updated on success, or freed on failure. + * @param size Size in bytes for the memory block to be allocated or + * reallocated + * @return Zero on success, an AVERROR error code on failure. + * @warning Pointers originating from the av_malloc() family of functions must + * not be passed to av_reallocp(). The former can be implemented using + * memalign() (or other functions), and there is no guarantee that + * pointers from such functions can be passed to realloc() at all. + * The situation is undefined according to POSIX and may crash with + * some libc implementations. + */ +av_warn_unused_result +int av_reallocp(void *ptr, size_t size); + +/** + * Allocate or reallocate 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 + * @param size Size of the single element + * @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 Pointers originating from the av_malloc() family of functions must + * not be passed to av_realloc(). The former can be implemented using + * memalign() (or other functions), and there is no guarantee that + * pointers from such functions can be passed to realloc() at all. + * The situation is undefined according to POSIX and may crash with + * some libc implementations. + */ +av_alloc_size(2, 3) void *av_realloc_array(void *ptr, size_t nmemb, size_t size); + +/** + * Allocate or reallocate 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 ptr Pointer to a pointer to a memory block already allocated + * with av_realloc(), or pointer to a pointer to NULL. + * The pointer is updated on success, or freed on failure. + * @param nmemb Number of elements + * @param size Size of the single element + * @return Zero on success, an AVERROR error code on failure. + * @warning Pointers originating from the av_malloc() family of functions must + * not be passed to av_realloc(). The former can be implemented using + * memalign() (or other functions), and there is no guarantee that + * pointers from such functions can be passed to realloc() at all. + * The situation is undefined according to POSIX and may crash with + * some libc implementations. + */ +av_alloc_size(2, 3) int av_reallocp_array(void *ptr, size_t nmemb, size_t size); + +/** + * Free a memory block which has been allocated with av_malloc(z)() or + * av_realloc(). + * @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. + * @see av_freep() + */ +void av_free(void *ptr); + +/** + * Allocate a block of size bytes 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, NULL if it cannot be allocated. + * @see av_malloc() + */ +void *av_mallocz(size_t size) av_malloc_attrib av_alloc_size(1); + +/** + * Allocate a block of nmemb * size bytes with alignment suitable for all + * memory accesses (including vectors if available on the CPU) and + * zero all the bytes of the block. + * The allocation will fail if nmemb * size is greater than or equal + * to INT_MAX. + * @param nmemb + * @param size + * @return Pointer to the allocated block, NULL if it cannot be allocated. + */ +void *av_calloc(size_t nmemb, size_t size) av_malloc_attrib; + +/** + * Allocate a block of size * nmemb bytes with av_mallocz(). + * @param nmemb Number of elements + * @param size Size of the single element + * @return Pointer to the allocated block, NULL if the block cannot + * be allocated. + * @see av_mallocz() + * @see av_malloc_array() + */ +av_alloc_size(1, 2) static inline void *av_mallocz_array(size_t nmemb, size_t size) +{ + if (!size || nmemb >= INT_MAX / size) + return NULL; + return av_mallocz(nmemb * size); +} + +/** + * Duplicate the string s. + * @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. + */ +char *av_strdup(const char *s) av_malloc_attrib; + +/** + * Duplicate a substring of the string s. + * @param s string to be duplicated + * @param len the maximum length of the resulting string (not counting the + * terminating byte). + * @return Pointer to a newly-allocated string containing a + * copy of s or NULL if the string cannot be allocated. + */ +char *av_strndup(const char *s, size_t len) av_malloc_attrib; + +/** + * Duplicate the buffer p. + * @param p buffer to be duplicated + * @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); + +/** + * Free a memory block which has been allocated with av_malloc(z)() or + * av_realloc() and set the pointer pointing to it to NULL. + * @param ptr Pointer to the pointer to the memory block which should + * be freed. + * @note passing a pointer to a NULL pointer is safe and leads to no action. + * @see av_free() + */ +void av_freep(void *ptr); + +/** + * Add 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 tab_ptr pointer to the array to grow + * @param nb_ptr pointer to the number of elements in the array + * @param 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. + * + * @param tab_ptr pointer to the array to grow + * @param nb_ptr pointer to the number of elements in the array + * @param elem element to add + * @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 tab_ptr pointer to the array to grow + * @param nb_ptr pointer to the number of elements in the array + * @param elem_size size in bytes of the elements in the array + * @param elem_data pointer to the data of the element to add. If NULL, the space of + * the new added element is not filled. + * @return pointer to the data of the element to copy in the new allocated space. + * If NULL, the new allocated space is left uninitialized." + * @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); + +/** + * Multiply two size_t values checking for overflow. + * @return 0 if success, AVERROR(EINVAL) if 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: only try the division if nelem and elsize + * are both greater 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 me allocated in one block. + */ +void av_max_alloc(size_t max); + +/** + * deliberately overlapping memcpy implementation + * @param dst destination buffer + * @param back how many bytes back we start (the initial size of the overlapping window), must be > 0 + * @param cnt number of bytes to copy, must be >= 0 + * + * 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); + +/** + * Reallocate the given block if it is not large enough, otherwise do nothing. + * + * @see av_realloc + */ +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. + * + * @param ptr pointer to pointer to already allocated buffer, overwritten with pointer to new buffer + * @param size size of the buffer *ptr points to + * @param min_size minimum size of *ptr buffer after returning, *ptr will be NULL and + * *size 0 if an error occurred. + */ +void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size); + +/** + * Allocate a buffer, reusing the given one if large enough. + * + * All newly allocated space is initially cleared + * 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. + * + * @param ptr pointer to pointer to already allocated buffer, overwritten with pointer to new buffer + * @param size size of the buffer *ptr points to + * @param min_size minimum size of *ptr buffer after returning, *ptr will be NULL and + * *size 0 if an error occurred. + */ +void av_fast_mallocz(void *ptr, unsigned int *size, size_t min_size); + +/** + * @} + */ + +#endif /* AVUTIL_MEM_H */ |