2 * default memory allocator for libavutil
3 * Copyright (c) 2002 Fabrice Bellard
5 * This file is part of Libav.
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * default memory allocator for libavutil
39 #include "intreadwrite.h"
44 #define malloc AV_JOIN(MALLOC_PREFIX, malloc)
45 #define memalign AV_JOIN(MALLOC_PREFIX, memalign)
46 #define posix_memalign AV_JOIN(MALLOC_PREFIX, posix_memalign)
47 #define realloc AV_JOIN(MALLOC_PREFIX, realloc)
48 #define free AV_JOIN(MALLOC_PREFIX, free)
50 void *malloc(size_t size);
51 void *memalign(size_t align, size_t size);
52 int posix_memalign(void **ptr, size_t align, size_t size);
53 void *realloc(void *ptr, size_t size);
56 #endif /* MALLOC_PREFIX */
58 /* You can redefine av_malloc and av_free in your project to use your
59 * memory allocator. You do not need to suppress this file because the
60 * linker will do it automatically. */
62 void *av_malloc(size_t size)
66 /* let's disallow possibly ambiguous cases */
67 if (size > (INT_MAX - 32) || !size)
70 #if HAVE_POSIX_MEMALIGN
71 if (posix_memalign(&ptr, 32, size))
73 #elif HAVE_ALIGNED_MALLOC
74 ptr = _aligned_malloc(size, 32);
76 ptr = memalign(32, size);
78 * Indeed, we should align it:
81 * on 32 for 586, PPro - K6-III
82 * on 64 for K7 (maybe for P3 too).
83 * Because L1 and L2 caches are aligned on those values.
84 * But I don't want to code such logic here!
87 * For AVX ASM. SSE / NEON needs only 16.
88 * Why not larger? Because I did not see a difference in benchmarks ...
91 * memalign(64) + 1 3071, 3051, 3032
92 * memalign(64) + 2 3051, 3032, 3041
93 * memalign(64) + 4 2911, 2896, 2915
94 * memalign(64) + 8 2545, 2554, 2550
95 * memalign(64) + 16 2543, 2572, 2563
96 * memalign(64) + 32 2546, 2545, 2571
97 * memalign(64) + 64 2570, 2533, 2558
99 * BTW, malloc seems to do 8-byte alignment by default here.
107 void *av_realloc(void *ptr, size_t size)
109 /* let's disallow possibly ambiguous cases */
110 if (size > (INT_MAX - 16))
113 #if HAVE_ALIGNED_MALLOC
114 return _aligned_realloc(ptr, size, 32);
116 return realloc(ptr, size);
120 int av_reallocp(void *ptr, size_t size)
129 memcpy(&val, ptr, sizeof(val));
130 val = av_realloc(val, size);
134 return AVERROR(ENOMEM);
137 memcpy(ptr, &val, sizeof(val));
141 void *av_realloc_array(void *ptr, size_t nmemb, size_t size)
143 if (!size || nmemb >= INT_MAX / size)
145 return av_realloc(ptr, nmemb * size);
148 int av_reallocp_array(void *ptr, size_t nmemb, size_t size)
152 if (!size || nmemb >= INT_MAX / size)
153 return AVERROR(ENOMEM);
159 memcpy(&val, ptr, sizeof(val));
160 val = av_realloc(val, nmemb * size);
163 return AVERROR(ENOMEM);
166 memcpy(ptr, &val, sizeof(val));
170 void av_free(void *ptr)
172 #if HAVE_ALIGNED_MALLOC
179 void av_freep(void *arg)
183 memcpy(&val, arg, sizeof(val));
184 memcpy(arg, &(void *){ NULL }, sizeof(val));
188 void *av_mallocz(size_t size)
190 void *ptr = av_malloc(size);
192 memset(ptr, 0, size);
196 char *av_strdup(const char *s)
200 int len = strlen(s) + 1;
201 ptr = av_realloc(NULL, len);
208 char *av_strndup(const char *s, size_t len)
210 char *ret = NULL, *end;
215 end = memchr(s, 0, len);
219 ret = av_realloc(NULL, len + 1);
228 static void fill16(uint8_t *dst, int len)
230 uint32_t v = AV_RN16(dst - 2);
246 static void fill24(uint8_t *dst, int len)
249 uint32_t v = AV_RB24(dst - 3);
250 uint32_t a = v << 8 | v >> 16;
251 uint32_t b = v << 16 | v >> 8;
252 uint32_t c = v << 24 | v;
254 uint32_t v = AV_RL24(dst - 3);
255 uint32_t a = v | v << 24;
256 uint32_t b = v >> 8 | v << 16;
257 uint32_t c = v >> 16 | v << 8;
286 static void fill32(uint8_t *dst, int len)
288 uint32_t v = AV_RN32(dst - 4);
302 void av_memcpy_backptr(uint8_t *dst, int back, int cnt)
304 const uint8_t *src = &dst[-back];
309 memset(dst, *src, cnt);
310 } else if (back == 2) {
312 } else if (back == 3) {
314 } else if (back == 4) {
319 while (cnt > blocklen) {
320 memcpy(dst, src, blocklen);
325 memcpy(dst, src, cnt);
329 AV_COPY32U(dst, src);
330 AV_COPY32U(dst + 4, src + 4);
336 AV_COPY32U(dst, src);
342 AV_COPY16U(dst, src);
352 void *av_fast_realloc(void *ptr, unsigned int *size, size_t min_size)
354 if (min_size < *size)
357 min_size = FFMAX(17 * min_size / 16 + 32, min_size);
359 ptr = av_realloc(ptr, min_size);
360 /* we could set this to the unmodified min_size but this is safer
361 * if the user lost the ptr and uses NULL now
371 void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size)
374 if (min_size < *size)
376 min_size = FFMAX(17 * min_size / 16 + 32, min_size);
378 *p = av_malloc(min_size);