mem.h 3.42 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
/*
 * 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
 */

/**
22
 * @file libavutil/mem.h
23
 * memory handling functions
24 25
 */

26 27
#ifndef AVUTIL_MEM_H
#define AVUTIL_MEM_H
28

29 30 31
#include "common.h"

#if AV_GCC_VERSION_AT_LEAST(3,1)
32 33 34 35 36
    #define av_malloc_attrib __attribute__((__malloc__))
#else
    #define av_malloc_attrib
#endif

37
#if (!defined(__ICC) || __ICC > 1100) && AV_GCC_VERSION_AT_LEAST(4,3)
38 39 40 41 42
    #define av_alloc_size(n) __attribute__((alloc_size(n)))
#else
    #define av_alloc_size(n)
#endif

43
/**
44
 * Allocates a block of size bytes with alignment suitable for all
45 46
 * memory accesses (including vectors if available on the CPU).
 * @param size Size in bytes for the memory block to be allocated.
47 48
 * @return Pointer to the allocated block, NULL if the block cannot
 * be allocated.
49
 * @see av_mallocz()
50
 */
51
void *av_malloc(unsigned int size) av_malloc_attrib av_alloc_size(1);
52 53

/**
54
 * Allocates or reallocates a block of memory.
55 56
 * If ptr is NULL and size > 0, allocates a new block. If \p
 * size is zero, frees the memory block pointed to by ptr.
57 58 59 60
 * @param size Size in bytes for the memory block to be allocated or
 * reallocated.
 * @param ptr Pointer to a memory block already allocated with
 * av_malloc(z)() or av_realloc() or NULL.
61 62
 * @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.
63
 * @see av_fast_realloc()
64
 */
65
void *av_realloc(void *ptr, unsigned int size) av_alloc_size(2);
66 67

/**
68
 * Frees a memory block which has been allocated with av_malloc(z)() or
69 70
 * av_realloc().
 * @param ptr Pointer to the memory block which should be freed.
71 72
 * @note ptr = NULL is explicitly allowed.
 * @note It is recommended that you use av_freep() instead.
73
 * @see av_freep()
74 75 76
 */
void av_free(void *ptr);

77
/**
78
 * Allocates a block of size bytes with alignment suitable for all
79
 * memory accesses (including vectors if available on the CPU) and
80
 * zeroes all the bytes of the block.
81
 * @param size Size in bytes for the memory block to be allocated.
82
 * @return Pointer to the allocated block, NULL if it cannot be allocated.
83 84
 * @see av_malloc()
 */
85
void *av_mallocz(unsigned int size) av_malloc_attrib av_alloc_size(1);
86 87

/**
88
 * Duplicates the string s.
89
 * @param s string to be duplicated
90
 * @return Pointer to a newly allocated string containing a
91
 * copy of s or NULL if the string cannot be allocated.
92
 */
93
char *av_strdup(const char *s) av_malloc_attrib;
94 95

/**
96 97
 * Frees a memory block which has been allocated with av_malloc(z)() or
 * av_realloc() and set the pointer pointing to it to NULL.
98 99 100
 * @param ptr Pointer to the pointer to the memory block which should
 * be freed.
 * @see av_free()
101 102 103
 */
void av_freep(void *ptr);

104
#endif /* AVUTIL_MEM_H */