blob: 8d1aa5fa841eb934b9b1846672d9c43dbe23bca3
1 | /* |
2 | * This file is part of FFmpeg. |
3 | * |
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. |
8 | * |
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. |
13 | * |
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 |
17 | */ |
18 | |
19 | #include <stdatomic.h> |
20 | #include <stdint.h> |
21 | #include <string.h> |
22 | |
23 | #include "buffer_internal.h" |
24 | #include "common.h" |
25 | #include "mem.h" |
26 | #include "thread.h" |
27 | |
28 | AVBufferRef *av_buffer_create(uint8_t *data, int size, |
29 | void (*free)(void *opaque, uint8_t *data), |
30 | void *opaque, int flags) |
31 | { |
32 | AVBufferRef *ref = NULL; |
33 | AVBuffer *buf = NULL; |
34 | |
35 | buf = av_mallocz(sizeof(*buf)); |
36 | if (!buf) |
37 | return NULL; |
38 | |
39 | buf->data = data; |
40 | buf->size = size; |
41 | buf->free = free ? free : av_buffer_default_free; |
42 | buf->opaque = opaque; |
43 | |
44 | atomic_init(&buf->refcount, 1); |
45 | |
46 | if (flags & AV_BUFFER_FLAG_READONLY) |
47 | buf->flags |= BUFFER_FLAG_READONLY; |
48 | |
49 | ref = av_mallocz(sizeof(*ref)); |
50 | if (!ref) { |
51 | av_freep(&buf); |
52 | return NULL; |
53 | } |
54 | |
55 | ref->buffer = buf; |
56 | ref->data = data; |
57 | ref->size = size; |
58 | |
59 | return ref; |
60 | } |
61 | |
62 | void av_buffer_default_free(void *opaque, uint8_t *data) |
63 | { |
64 | av_free(data); |
65 | } |
66 | |
67 | AVBufferRef *av_buffer_alloc(int size) |
68 | { |
69 | AVBufferRef *ret = NULL; |
70 | uint8_t *data = NULL; |
71 | |
72 | data = av_malloc(size); |
73 | if (!data) |
74 | return NULL; |
75 | |
76 | ret = av_buffer_create(data, size, av_buffer_default_free, NULL, 0); |
77 | if (!ret) |
78 | av_freep(&data); |
79 | |
80 | return ret; |
81 | } |
82 | |
83 | AVBufferRef *av_buffer_allocz(int size) |
84 | { |
85 | AVBufferRef *ret = av_buffer_alloc(size); |
86 | if (!ret) |
87 | return NULL; |
88 | |
89 | memset(ret->data, 0, size); |
90 | return ret; |
91 | } |
92 | |
93 | AVBufferRef *av_buffer_ref(AVBufferRef *buf) |
94 | { |
95 | AVBufferRef *ret = av_mallocz(sizeof(*ret)); |
96 | |
97 | if (!ret) |
98 | return NULL; |
99 | |
100 | *ret = *buf; |
101 | |
102 | atomic_fetch_add_explicit(&buf->buffer->refcount, 1, memory_order_relaxed); |
103 | |
104 | return ret; |
105 | } |
106 | |
107 | static void buffer_replace(AVBufferRef **dst, AVBufferRef **src) |
108 | { |
109 | AVBuffer *b; |
110 | |
111 | b = (*dst)->buffer; |
112 | |
113 | if (src) { |
114 | **dst = **src; |
115 | av_freep(src); |
116 | } else |
117 | av_freep(dst); |
118 | |
119 | if (atomic_fetch_add_explicit(&b->refcount, -1, memory_order_acq_rel) == 1) { |
120 | b->free(b->opaque, b->data); |
121 | av_freep(&b); |
122 | } |
123 | } |
124 | |
125 | void av_buffer_unref(AVBufferRef **buf) |
126 | { |
127 | if (!buf || !*buf) |
128 | return; |
129 | |
130 | buffer_replace(buf, NULL); |
131 | } |
132 | |
133 | int av_buffer_is_writable(const AVBufferRef *buf) |
134 | { |
135 | if (buf->buffer->flags & AV_BUFFER_FLAG_READONLY) |
136 | return 0; |
137 | |
138 | return atomic_load(&buf->buffer->refcount) == 1; |
139 | } |
140 | |
141 | void *av_buffer_get_opaque(const AVBufferRef *buf) |
142 | { |
143 | return buf->buffer->opaque; |
144 | } |
145 | |
146 | int av_buffer_get_ref_count(const AVBufferRef *buf) |
147 | { |
148 | return atomic_load(&buf->buffer->refcount); |
149 | } |
150 | |
151 | int av_buffer_make_writable(AVBufferRef **pbuf) |
152 | { |
153 | AVBufferRef *newbuf, *buf = *pbuf; |
154 | |
155 | if (av_buffer_is_writable(buf)) |
156 | return 0; |
157 | |
158 | newbuf = av_buffer_alloc(buf->size); |
159 | if (!newbuf) |
160 | return AVERROR(ENOMEM); |
161 | |
162 | memcpy(newbuf->data, buf->data, buf->size); |
163 | |
164 | buffer_replace(pbuf, &newbuf); |
165 | |
166 | return 0; |
167 | } |
168 | |
169 | int av_buffer_realloc(AVBufferRef **pbuf, int size) |
170 | { |
171 | AVBufferRef *buf = *pbuf; |
172 | uint8_t *tmp; |
173 | |
174 | if (!buf) { |
175 | /* allocate a new buffer with av_realloc(), so it will be reallocatable |
176 | * later */ |
177 | uint8_t *data = av_realloc(NULL, size); |
178 | if (!data) |
179 | return AVERROR(ENOMEM); |
180 | |
181 | buf = av_buffer_create(data, size, av_buffer_default_free, NULL, 0); |
182 | if (!buf) { |
183 | av_freep(&data); |
184 | return AVERROR(ENOMEM); |
185 | } |
186 | |
187 | buf->buffer->flags |= BUFFER_FLAG_REALLOCATABLE; |
188 | *pbuf = buf; |
189 | |
190 | return 0; |
191 | } else if (buf->size == size) |
192 | return 0; |
193 | |
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; |
198 | |
199 | av_buffer_realloc(&new, size); |
200 | if (!new) |
201 | return AVERROR(ENOMEM); |
202 | |
203 | memcpy(new->data, buf->data, FFMIN(size, buf->size)); |
204 | |
205 | buffer_replace(pbuf, &new); |
206 | return 0; |
207 | } |
208 | |
209 | tmp = av_realloc(buf->buffer->data, size); |
210 | if (!tmp) |
211 | return AVERROR(ENOMEM); |
212 | |
213 | buf->buffer->data = buf->data = tmp; |
214 | buf->buffer->size = buf->size = size; |
215 | return 0; |
216 | } |
217 | |
218 | AVBufferPool *av_buffer_pool_init2(int size, void *opaque, |
219 | AVBufferRef* (*alloc)(void *opaque, int size), |
220 | void (*pool_free)(void *opaque)) |
221 | { |
222 | AVBufferPool *pool = av_mallocz(sizeof(*pool)); |
223 | if (!pool) |
224 | return NULL; |
225 | |
226 | ff_mutex_init(&pool->mutex, NULL); |
227 | |
228 | pool->size = size; |
229 | pool->opaque = opaque; |
230 | pool->alloc2 = alloc; |
231 | pool->pool_free = pool_free; |
232 | |
233 | atomic_init(&pool->refcount, 1); |
234 | |
235 | return pool; |
236 | } |
237 | |
238 | AVBufferPool *av_buffer_pool_init(int size, AVBufferRef* (*alloc)(int size)) |
239 | { |
240 | AVBufferPool *pool = av_mallocz(sizeof(*pool)); |
241 | if (!pool) |
242 | return NULL; |
243 | |
244 | ff_mutex_init(&pool->mutex, NULL); |
245 | |
246 | pool->size = size; |
247 | pool->alloc = alloc ? alloc : av_buffer_alloc; |
248 | |
249 | atomic_init(&pool->refcount, 1); |
250 | |
251 | return pool; |
252 | } |
253 | |
254 | /* |
255 | * This function gets called when the pool has been uninited and |
256 | * all the buffers returned to it. |
257 | */ |
258 | static void buffer_pool_free(AVBufferPool *pool) |
259 | { |
260 | while (pool->pool) { |
261 | BufferPoolEntry *buf = pool->pool; |
262 | pool->pool = buf->next; |
263 | |
264 | buf->free(buf->opaque, buf->data); |
265 | av_freep(&buf); |
266 | } |
267 | ff_mutex_destroy(&pool->mutex); |
268 | |
269 | if (pool->pool_free) |
270 | pool->pool_free(pool->opaque); |
271 | |
272 | av_freep(&pool); |
273 | } |
274 | |
275 | void av_buffer_pool_uninit(AVBufferPool **ppool) |
276 | { |
277 | AVBufferPool *pool; |
278 | |
279 | if (!ppool || !*ppool) |
280 | return; |
281 | pool = *ppool; |
282 | *ppool = NULL; |
283 | |
284 | if (atomic_fetch_add_explicit(&pool->refcount, -1, memory_order_acq_rel) == 1) |
285 | buffer_pool_free(pool); |
286 | } |
287 | |
288 | static void pool_release_buffer(void *opaque, uint8_t *data) |
289 | { |
290 | BufferPoolEntry *buf = opaque; |
291 | AVBufferPool *pool = buf->pool; |
292 | |
293 | if(CONFIG_MEMORY_POISONING) |
294 | memset(buf->data, FF_MEMORY_POISON, pool->size); |
295 | |
296 | ff_mutex_lock(&pool->mutex); |
297 | buf->next = pool->pool; |
298 | pool->pool = buf; |
299 | ff_mutex_unlock(&pool->mutex); |
300 | |
301 | if (atomic_fetch_add_explicit(&pool->refcount, -1, memory_order_acq_rel) == 1) |
302 | buffer_pool_free(pool); |
303 | } |
304 | |
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) |
308 | { |
309 | BufferPoolEntry *buf; |
310 | AVBufferRef *ret; |
311 | |
312 | ret = pool->alloc2 ? pool->alloc2(pool->opaque, pool->size) : |
313 | pool->alloc(pool->size); |
314 | if (!ret) |
315 | return NULL; |
316 | |
317 | buf = av_mallocz(sizeof(*buf)); |
318 | if (!buf) { |
319 | av_buffer_unref(&ret); |
320 | return NULL; |
321 | } |
322 | |
323 | buf->data = ret->buffer->data; |
324 | buf->opaque = ret->buffer->opaque; |
325 | buf->free = ret->buffer->free; |
326 | buf->pool = pool; |
327 | |
328 | ret->buffer->opaque = buf; |
329 | ret->buffer->free = pool_release_buffer; |
330 | |
331 | return ret; |
332 | } |
333 | |
334 | AVBufferRef *av_buffer_pool_get(AVBufferPool *pool) |
335 | { |
336 | AVBufferRef *ret; |
337 | BufferPoolEntry *buf; |
338 | |
339 | ff_mutex_lock(&pool->mutex); |
340 | buf = pool->pool; |
341 | if (buf) { |
342 | ret = av_buffer_create(buf->data, pool->size, pool_release_buffer, |
343 | buf, 0); |
344 | if (ret) { |
345 | pool->pool = buf->next; |
346 | buf->next = NULL; |
347 | } |
348 | } else { |
349 | ret = pool_alloc_buffer(pool); |
350 | } |
351 | ff_mutex_unlock(&pool->mutex); |
352 | |
353 | if (ret) |
354 | atomic_fetch_add_explicit(&pool->refcount, 1, memory_order_relaxed); |
355 | |
356 | return ret; |
357 | } |
358 |