| /* |
| * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> |
| * |
| * This file is part of Libav. |
| * |
| * Libav 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. |
| * |
| * Libav 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 Libav; 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 "avutil.h" |
| |
| /** |
| * @addtogroup lavu_mem |
| * @{ |
| */ |
| |
| |
| #if defined(__ICC) && __ICC < 1200 || 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. |
| * 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. |
| */ |
| 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 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; |
| |
| /** |
| * 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. |
| * @see av_free() |
| */ |
| void av_freep(void *ptr); |
| |
| /** |
| * deliberately overlapping memcpy implementation |
| * @param dst destination buffer |
| * @param back how many bytes back we start (the initial size of the overlapping window) |
| * @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); |
| |
| /** |
| * @} |
| */ |
| |
| #endif /* AVUTIL_MEM_H */ |
