2 * This file is part of FFmpeg.
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 #include <stdatomic.h>
23 #include "buffer_internal.h"
28 AVBufferRef *av_buffer_create(uint8_t *data, int size,
29 void (*free)(void *opaque, uint8_t *data),
30 void *opaque, int flags)
32 AVBufferRef *ref = NULL;
35 buf = av_mallocz(sizeof(*buf));
41 buf->free = free ? free : av_buffer_default_free;
44 atomic_init(&buf->refcount, 1);
46 if (flags & AV_BUFFER_FLAG_READONLY)
47 buf->flags |= BUFFER_FLAG_READONLY;
49 ref = av_mallocz(sizeof(*ref));
62 void av_buffer_default_free(void *opaque, uint8_t *data)
67 AVBufferRef *av_buffer_alloc(int size)
69 AVBufferRef *ret = NULL;
72 data = av_malloc(size);
76 ret = av_buffer_create(data, size, av_buffer_default_free, NULL, 0);
83 AVBufferRef *av_buffer_allocz(int size)
85 AVBufferRef *ret = av_buffer_alloc(size);
89 memset(ret->data, 0, size);
93 AVBufferRef *av_buffer_ref(AVBufferRef *buf)
95 AVBufferRef *ret = av_mallocz(sizeof(*ret));
102 atomic_fetch_add_explicit(&buf->buffer->refcount, 1, memory_order_relaxed);
107 static void buffer_replace(AVBufferRef **dst, AVBufferRef **src)
119 if (atomic_fetch_add_explicit(&b->refcount, -1, memory_order_acq_rel) == 1) {
120 b->free(b->opaque, b->data);
125 void av_buffer_unref(AVBufferRef **buf)
130 buffer_replace(buf, NULL);
133 int av_buffer_is_writable(const AVBufferRef *buf)
135 if (buf->buffer->flags & AV_BUFFER_FLAG_READONLY)
138 return atomic_load(&buf->buffer->refcount) == 1;
141 void *av_buffer_get_opaque(const AVBufferRef *buf)
143 return buf->buffer->opaque;
146 int av_buffer_get_ref_count(const AVBufferRef *buf)
148 return atomic_load(&buf->buffer->refcount);
151 int av_buffer_make_writable(AVBufferRef **pbuf)
153 AVBufferRef *newbuf, *buf = *pbuf;
155 if (av_buffer_is_writable(buf))
158 newbuf = av_buffer_alloc(buf->size);
160 return AVERROR(ENOMEM);
162 memcpy(newbuf->data, buf->data, buf->size);
164 buffer_replace(pbuf, &newbuf);
169 int av_buffer_realloc(AVBufferRef **pbuf, int size)
171 AVBufferRef *buf = *pbuf;
175 /* allocate a new buffer with av_realloc(), so it will be reallocatable
177 uint8_t *data = av_realloc(NULL, size);
179 return AVERROR(ENOMEM);
181 buf = av_buffer_create(data, size, av_buffer_default_free, NULL, 0);
184 return AVERROR(ENOMEM);
187 buf->buffer->flags |= BUFFER_FLAG_REALLOCATABLE;
191 } else if (buf->size == size)
194 if (!(buf->buffer->flags & BUFFER_FLAG_REALLOCATABLE) ||
195 !av_buffer_is_writable(buf) || buf->data != buf->buffer->data) {
196 /* cannot realloc, allocate a new reallocable buffer and copy data */
197 AVBufferRef *new = NULL;
199 av_buffer_realloc(&new, size);
201 return AVERROR(ENOMEM);
203 memcpy(new->data, buf->data, FFMIN(size, buf->size));
205 buffer_replace(pbuf, &new);
209 tmp = av_realloc(buf->buffer->data, size);
211 return AVERROR(ENOMEM);
213 buf->buffer->data = buf->data = tmp;
214 buf->buffer->size = buf->size = size;
218 AVBufferPool *av_buffer_pool_init2(int size, void *opaque,
219 AVBufferRef* (*alloc)(void *opaque, int size),
220 void (*pool_free)(void *opaque))
222 AVBufferPool *pool = av_mallocz(sizeof(*pool));
226 ff_mutex_init(&pool->mutex, NULL);
229 pool->opaque = opaque;
230 pool->alloc2 = alloc;
231 pool->pool_free = pool_free;
233 atomic_init(&pool->refcount, 1);
238 AVBufferPool *av_buffer_pool_init(int size, AVBufferRef* (*alloc)(int size))
240 AVBufferPool *pool = av_mallocz(sizeof(*pool));
244 ff_mutex_init(&pool->mutex, NULL);
247 pool->alloc = alloc ? alloc : av_buffer_alloc;
249 atomic_init(&pool->refcount, 1);
255 * This function gets called when the pool has been uninited and
256 * all the buffers returned to it.
258 static void buffer_pool_free(AVBufferPool *pool)
261 BufferPoolEntry *buf = pool->pool;
262 pool->pool = buf->next;
264 buf->free(buf->opaque, buf->data);
267 ff_mutex_destroy(&pool->mutex);
270 pool->pool_free(pool->opaque);
275 void av_buffer_pool_uninit(AVBufferPool **ppool)
279 if (!ppool || !*ppool)
284 if (atomic_fetch_add_explicit(&pool->refcount, -1, memory_order_acq_rel) == 1)
285 buffer_pool_free(pool);
288 static void pool_release_buffer(void *opaque, uint8_t *data)
290 BufferPoolEntry *buf = opaque;
291 AVBufferPool *pool = buf->pool;
293 if(CONFIG_MEMORY_POISONING)
294 memset(buf->data, FF_MEMORY_POISON, pool->size);
296 ff_mutex_lock(&pool->mutex);
297 buf->next = pool->pool;
299 ff_mutex_unlock(&pool->mutex);
301 if (atomic_fetch_add_explicit(&pool->refcount, -1, memory_order_acq_rel) == 1)
302 buffer_pool_free(pool);
305 /* allocate a new buffer and override its free() callback so that
306 * it is returned to the pool on free */
307 static AVBufferRef *pool_alloc_buffer(AVBufferPool *pool)
309 BufferPoolEntry *buf;
312 ret = pool->alloc2 ? pool->alloc2(pool->opaque, pool->size) :
313 pool->alloc(pool->size);
317 buf = av_mallocz(sizeof(*buf));
319 av_buffer_unref(&ret);
323 buf->data = ret->buffer->data;
324 buf->opaque = ret->buffer->opaque;
325 buf->free = ret->buffer->free;
328 ret->buffer->opaque = buf;
329 ret->buffer->free = pool_release_buffer;
334 AVBufferRef *av_buffer_pool_get(AVBufferPool *pool)
337 BufferPoolEntry *buf;
339 ff_mutex_lock(&pool->mutex);
342 ret = av_buffer_create(buf->data, pool->size, pool_release_buffer,
345 pool->pool = buf->next;
349 ret = pool_alloc_buffer(pool);
351 ff_mutex_unlock(&pool->mutex);
354 atomic_fetch_add_explicit(&pool->refcount, 1, memory_order_relaxed);