FFmpeg: libavcodec/avpacket.c Source File

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libavcodec

avpacket.c

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1 /*

2 * AVPacket functions for libavcodec

4 *

5 * This file is part of FFmpeg.

6 *

7 * FFmpeg 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.

11 *

12 * FFmpeg 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.

16 *

17 * You should have received a copy of the GNU Lesser General Public

18 * License along with FFmpeg; if not, write to the Free Software

19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

20 */

22 #include <string.h>

24 #include "libavutil/avassert.h"

25 #include "libavutil/common.h"

26 #include "libavutil/internal.h"

27 #include "libavutil/mathematics.h"

28 #include "libavutil/mem.h"

29 #include "avcodec.h"

30 #include "bytestream.h"

31 #include "internal.h"

33 #if FF_API_DESTRUCT_PACKET

35 void av_destruct_packet(AVPacket *pkt)

36 {

37 av_freep(&pkt->data);

38 pkt->size = 0;

39 }

41 /* a dummy destruct callback for the callers that assume AVPacket.destruct ==

42 * NULL => static data */

43 static void dummy_destruct_packet(AVPacket *pkt)

44 {

45 av_assert0(0);

46 }

47 #endif

49 void av_init_packet(AVPacket *pkt)

50 {

51 pkt->pts = AV_NOPTS_VALUE;

52 pkt->dts = AV_NOPTS_VALUE;

53 pkt->pos = -1;

54 pkt->duration = 0;

55 pkt->convergence_duration = 0;

56 pkt->flags = 0;

57 pkt->stream_index = 0;

58 #if FF_API_DESTRUCT_PACKET

59 FF_DISABLE_DEPRECATION_WARNINGS

60 pkt->destruct = NULL;

61 FF_ENABLE_DEPRECATION_WARNINGS

62 #endif

63 pkt->buf = NULL;

64 pkt->side_data = NULL;

65 pkt->side_data_elems = 0;

66 }

68 static int packet_alloc(AVBufferRef **buf, int size)

69 {

70 int ret;

71 if ((unsigned)size >= (unsigned)size + FF_INPUT_BUFFER_PADDING_SIZE)

72 return AVERROR(EINVAL);

74 ret = av_buffer_realloc(buf, size + FF_INPUT_BUFFER_PADDING_SIZE);

75 if (ret < 0)

76 return ret;

78 memset((*buf)->data + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);

80 return 0;

81 }

83 int av_new_packet(AVPacket *pkt, int size)

84 {

85 AVBufferRef *buf = NULL;

86 int ret = packet_alloc(&buf, size);

87 if (ret < 0)

88 return ret;

90 av_init_packet(pkt);

91 pkt->buf = buf;

92 pkt->data = buf->data;

93 pkt->size = size;

94 #if FF_API_DESTRUCT_PACKET

95 FF_DISABLE_DEPRECATION_WARNINGS

96 pkt->destruct = dummy_destruct_packet;

97 FF_ENABLE_DEPRECATION_WARNINGS

98 #endif

100 return 0;

101 }

102

103 void av_shrink_packet(AVPacket *pkt, int size)

104 {

105 if (pkt->size <= size)

106 return;

107 pkt->size = size;

108 memset(pkt->data + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);

109 }

110

111 int av_grow_packet(AVPacket *pkt, int grow_by)

112 {

113 int new_size;

114 av_assert0((unsigned)pkt->size <= INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE);

115 if (!pkt->size)

116 return av_new_packet(pkt, grow_by);

117 if ((unsigned)grow_by >

118 INT_MAX - (pkt->size + FF_INPUT_BUFFER_PADDING_SIZE))

119 return -1;

120

121 new_size = pkt->size + grow_by + FF_INPUT_BUFFER_PADDING_SIZE;

122 if (pkt->buf) {

123 int ret = av_buffer_realloc(&pkt->buf, new_size);

124 if (ret < 0)

125 return ret;

126 } else {

127 pkt->buf = av_buffer_alloc(new_size);

128 if (!pkt->buf)

129 return AVERROR(ENOMEM);

130 memcpy(pkt->buf->data, pkt->data, FFMIN(pkt->size, pkt->size + grow_by));

131 #if FF_API_DESTRUCT_PACKET

132 FF_DISABLE_DEPRECATION_WARNINGS

133 pkt->destruct = dummy_destruct_packet;

134 FF_ENABLE_DEPRECATION_WARNINGS

135 #endif

136 }

137 pkt->data = pkt->buf->data;

138 pkt->size += grow_by;

139 memset(pkt->data + pkt->size, 0, FF_INPUT_BUFFER_PADDING_SIZE);

140

141 return 0;

142 }

143

144 int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size)

145 {

146 if (size >= INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE)

147 return AVERROR(EINVAL);

148

149 pkt->buf = av_buffer_create(data, size + FF_INPUT_BUFFER_PADDING_SIZE,

150 av_buffer_default_free, NULL, 0);

151 if (!pkt->buf)

152 return AVERROR(ENOMEM);

153

154 pkt->data = data;

155 pkt->size = size;

156 #if FF_API_DESTRUCT_PACKET

157 FF_DISABLE_DEPRECATION_WARNINGS

158 pkt->destruct = dummy_destruct_packet;

159 FF_ENABLE_DEPRECATION_WARNINGS

160 #endif

161

162 return 0;

163 }

164

165 #define ALLOC_MALLOC(data, size) data = av_malloc(size)

166 #define ALLOC_BUF(data, size) \

167 do { \

168 av_buffer_realloc(&pkt->buf, size); \

169 data = pkt->buf ? pkt->buf->data : NULL; \

170 } while (0)

171

172 #define DUP_DATA(dst, src, size, padding, ALLOC) \

173 do { \

174 void *data; \

175 if (padding) { \

176 if ((unsigned)(size) > \

177 (unsigned)(size) + FF_INPUT_BUFFER_PADDING_SIZE) \

178 goto failed_alloc; \

179 ALLOC(data, size + FF_INPUT_BUFFER_PADDING_SIZE); \

180 } else { \

181 ALLOC(data, size); \

182 } \

183 if (!data) \

184 goto failed_alloc; \

185 memcpy(data, src, size); \

186 if (padding) \

187 memset((uint8_t *)data + size, 0, \

188 FF_INPUT_BUFFER_PADDING_SIZE); \

189 dst = data; \

190 } while (0)

191

192 /* Makes duplicates of data, side_data, but does not copy any other fields */

193 static int copy_packet_data(AVPacket *pkt, const AVPacket *src, int dup)

194 {

195 pkt->data = NULL;

196 pkt->side_data = NULL;

197 if (pkt->buf) {

198 AVBufferRef *ref = av_buffer_ref(src->buf);

199 if (!ref)

200 return AVERROR(ENOMEM);

201 pkt->buf = ref;

202 pkt->data = ref->data;

203 } else {

204 DUP_DATA(pkt->data, src->data, pkt->size, 1, ALLOC_BUF);

205 }

206 #if FF_API_DESTRUCT_PACKET

207 FF_DISABLE_DEPRECATION_WARNINGS

208 pkt->destruct = dummy_destruct_packet;

209 FF_ENABLE_DEPRECATION_WARNINGS

210 #endif

211 if (pkt->side_data_elems && dup)

212 pkt->side_data = src->side_data;

213 if (pkt->side_data_elems && !dup) {

214 return av_copy_packet_side_data(pkt, src);

215 }

216 return 0;

217

218 failed_alloc:

219 av_free_packet(pkt);

220 return AVERROR(ENOMEM);

221 }

222

223 int av_copy_packet_side_data(AVPacket *pkt, const AVPacket *src)

224 {

225 if (src->side_data_elems) {

226 int i;

227 DUP_DATA(pkt->side_data, src->side_data,

228 src->side_data_elems * sizeof(*src->side_data), 0, ALLOC_MALLOC);

229 if (src != pkt) {

230 memset(pkt->side_data, 0,

231 src->side_data_elems * sizeof(*src->side_data));

232 }

233 for (i = 0; i < src->side_data_elems; i++) {

234 DUP_DATA(pkt->side_data[i].data, src->side_data[i].data,

235 src->side_data[i].size, 1, ALLOC_MALLOC);

236 pkt->side_data[i].size = src->side_data[i].size;

237 pkt->side_data[i].type = src->side_data[i].type;

238 }

239 }

240 pkt->side_data_elems = src->side_data_elems;

241 return 0;

242

243 failed_alloc:

244 av_free_packet(pkt);

245 return AVERROR(ENOMEM);

246 }

247

248 int av_dup_packet(AVPacket *pkt)

249 {

250 AVPacket tmp_pkt;

251

252 FF_DISABLE_DEPRECATION_WARNINGS

253 if (!pkt->buf && pkt->data

254 #if FF_API_DESTRUCT_PACKET

255 && !pkt->destruct

256 #endif

257 ) {

258 FF_ENABLE_DEPRECATION_WARNINGS

259 tmp_pkt = *pkt;

260 return copy_packet_data(pkt, &tmp_pkt, 1);

261 }

262 return 0;

263 }

264

265 int av_copy_packet(AVPacket *dst, const AVPacket *src)

266 {

267 *dst = *src;

268 return copy_packet_data(dst, src, 0);

269 }

270

271 void av_packet_free_side_data(AVPacket *pkt)

272 {

273 int i;

274 for (i = 0; i < pkt->side_data_elems; i++)

275 av_freep(&pkt->side_data[i].data);

276 av_freep(&pkt->side_data);

277 pkt->side_data_elems = 0;

278 }

279

280 void av_free_packet(AVPacket *pkt)

281 {

282 if (pkt) {

283 FF_DISABLE_DEPRECATION_WARNINGS

284 if (pkt->buf)

285 av_buffer_unref(&pkt->buf);

286 #if FF_API_DESTRUCT_PACKET

287 else if (pkt->destruct)

288 pkt->destruct(pkt);

289 pkt->destruct = NULL;

290 #endif

291 FF_ENABLE_DEPRECATION_WARNINGS

292 pkt->data = NULL;

293 pkt->size = 0;

294

295 av_packet_free_side_data(pkt);

296 }

297 }

298

299 uint8_t *av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,

300 int size)

301 {

302 int elems = pkt->side_data_elems;

303

304 if ((unsigned)elems + 1 > INT_MAX / sizeof(*pkt->side_data))

305 return NULL;

306 if ((unsigned)size > INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE)

307 return NULL;

308

309 pkt->side_data = av_realloc(pkt->side_data,

310 (elems + 1) * sizeof(*pkt->side_data));

311 if (!pkt->side_data)

312 return NULL;

313

314 pkt->side_data[elems].data = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE);

315 if (!pkt->side_data[elems].data)

316 return NULL;

317 pkt->side_data[elems].size = size;

318 pkt->side_data[elems].type = type;

319 pkt->side_data_elems++;

320

321 return pkt->side_data[elems].data;

322 }

323

324 uint8_t *av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,

325 int *size)

326 {

327 int i;

328

329 for (i = 0; i < pkt->side_data_elems; i++) {

330 if (pkt->side_data[i].type == type) {

331 if (size)

332 *size = pkt->side_data[i].size;

333 return pkt->side_data[i].data;

334 }

335 }

336 return NULL;

337 }

338

339 #define FF_MERGE_MARKER 0x8c4d9d108e25e9feULL

340

341 int av_packet_merge_side_data(AVPacket *pkt){

342 if(pkt->side_data_elems){

343 AVBufferRef *buf;

344 int i;

345 uint8_t *p;

346 uint64_t size= pkt->size + 8LL + FF_INPUT_BUFFER_PADDING_SIZE;

347 AVPacket old= *pkt;

348 for (i=0; i<old.side_data_elems; i++) {

349 size += old.side_data[i].size + 5LL;

350 }

351 if (size > INT_MAX)

352 return AVERROR(EINVAL);

353 buf = av_buffer_alloc(size);

354 if (!buf)

355 return AVERROR(ENOMEM);

356 pkt->buf = buf;

357 pkt->data = p = buf->data;

358 #if FF_API_DESTRUCT_PACKET

359 FF_DISABLE_DEPRECATION_WARNINGS

360 pkt->destruct = dummy_destruct_packet;

361 FF_ENABLE_DEPRECATION_WARNINGS

362 #endif

363 pkt->size = size - FF_INPUT_BUFFER_PADDING_SIZE;

364 bytestream_put_buffer(&p, old.data, old.size);

365 for (i=old.side_data_elems-1; i>=0; i--) {

366 bytestream_put_buffer(&p, old.side_data[i].data, old.side_data[i].size);

367 bytestream_put_be32(&p, old.side_data[i].size);

368 *p++ = old.side_data[i].type | ((i==old.side_data_elems-1)*128);

369 }

370 bytestream_put_be64(&p, FF_MERGE_MARKER);

371 av_assert0(p-pkt->data == pkt->size);

372 memset(p, 0, FF_INPUT_BUFFER_PADDING_SIZE);

373 av_free_packet(&old);

374 pkt->side_data_elems = 0;

375 pkt->side_data = NULL;

376 return 1;

377 }

378 return 0;

379 }

380

381 int av_packet_split_side_data(AVPacket *pkt){

382 if (!pkt->side_data_elems && pkt->size >12 && AV_RB64(pkt->data + pkt->size - 8) == FF_MERGE_MARKER){

383 int i;

384 unsigned int size;

385 uint8_t *p;

386

387 p = pkt->data + pkt->size - 8 - 5;

388 for (i=1; ; i++){

389 size = AV_RB32(p);

390 if (size>INT_MAX || p - pkt->data < size)

391 return 0;

392 if (p[4]&128)

393 break;

394 p-= size+5;

395 }

396

397 pkt->side_data = av_malloc_array(i, sizeof(*pkt->side_data));

398 if (!pkt->side_data)

399 return AVERROR(ENOMEM);

400

401 p= pkt->data + pkt->size - 8 - 5;

402 for (i=0; ; i++){

403 size= AV_RB32(p);

404 av_assert0(size<=INT_MAX && p - pkt-> data >= size);

405 pkt->side_data[i].data = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE);

406 pkt->side_data[i].size = size;

407 pkt->side_data[i].type = p[4]&127;

408 if (!pkt->side_data[i].data)

409 return AVERROR(ENOMEM);

410 memcpy(pkt->side_data[i].data, p-size, size);

411 pkt->size -= size + 5;

412 if(p[4]&128)

413 break;

414 p-= size+5;

415 }

416 pkt->size -= 8;

417 pkt->side_data_elems = i+1;

418 return 1;

419 }

420 return 0;

421 }

422

423 uint8_t *av_packet_pack_dictionary(AVDictionary *dict, int *size)

424 {

425 AVDictionaryEntry *t = NULL;

426 uint8_t *data = NULL;

427 *size = 0;

428

429 if (!dict)

430 return NULL;

431

432 while ((t = av_dict_get(dict, "", t, AV_DICT_IGNORE_SUFFIX))) {

433 const size_t keylen = strlen(t->key);

434 const size_t valuelen = strlen(t->value);

435 const size_t new_size = *size + keylen + 1 + valuelen + 1;

436 uint8_t *const new_data = av_realloc(data, new_size);

437

438 if (!new_data)

439 goto fail;

440 data = new_data;

441 if (new_size > INT_MAX)

442 goto fail;

443

444 memcpy(data + *size, t->key, keylen + 1);

445 memcpy(data + *size + keylen + 1, t->value, valuelen + 1);

446

447 *size = new_size;

448 }

449

450 return data;

451

452 fail:

453 av_freep(&data);

454 *size = 0;

455 return NULL;

456 }

457

458 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict)

459 {

460 const uint8_t *end = data + size;

461 int ret = 0;

462

463 if (!dict || !data || !size)

464 return ret;

465 if (size && end[-1])

466 return AVERROR_INVALIDDATA;

467 while (data < end) {

468 const uint8_t *key = data;

469 const uint8_t *val = data + strlen(key) + 1;

470

471 if (val >= end)

472 return AVERROR_INVALIDDATA;

473

474 ret = av_dict_set(dict, key, val, 0);

475 if (ret < 0)

476 break;

477 data = val + strlen(val) + 1;

478 }

479

480 return ret;

481 }

482

483 int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,

484 int size)

485 {

486 int i;

487

488 for (i = 0; i < pkt->side_data_elems; i++) {

489 if (pkt->side_data[i].type == type) {

490 if (size > pkt->side_data[i].size)

491 return AVERROR(ENOMEM);

492 pkt->side_data[i].size = size;

493 return 0;

494 }

495 }

496 return AVERROR(ENOENT);

497 }

498

499 int av_packet_copy_props(AVPacket *dst, const AVPacket *src)

500 {

501 int i;

502

503 dst->pts = src->pts;

504 dst->dts = src->dts;

505 dst->pos = src->pos;

506 dst->duration = src->duration;

507 dst->convergence_duration = src->convergence_duration;

508 dst->flags = src->flags;

509 dst->stream_index = src->stream_index;

510

511 for (i = 0; i < src->side_data_elems; i++) {

512 enum AVPacketSideDataType type = src->side_data[i].type;

513 int size = src->side_data[i].size;

514 uint8_t *src_data = src->side_data[i].data;

515 uint8_t *dst_data = av_packet_new_side_data(dst, type, size);

516

517 if (!dst_data) {

518 av_packet_free_side_data(dst);

519 return AVERROR(ENOMEM);

520 }

521 memcpy(dst_data, src_data, size);

522 }

523

524 return 0;

525 }

526

527 void av_packet_unref(AVPacket *pkt)

528 {

529 av_packet_free_side_data(pkt);

530 av_buffer_unref(&pkt->buf);

531 av_init_packet(pkt);

532 pkt->data = NULL;

533 pkt->size = 0;

534 }

535

536 int av_packet_ref(AVPacket *dst, const AVPacket *src)

537 {

538 int ret;

539

540 ret = av_packet_copy_props(dst, src);

541 if (ret < 0)

542 return ret;

543

544 if (!src->buf) {

545 ret = packet_alloc(&dst->buf, src->size);

546 if (ret < 0)

547 goto fail;

548 memcpy(dst->buf->data, src->data, src->size);

549 } else {

550 dst->buf = av_buffer_ref(src->buf);

551 if (!dst->buf) {

552 ret = AVERROR(ENOMEM);

553 goto fail;

554 }

555 }

556

557 dst->size = src->size;

558 dst->data = dst->buf->data;

559 return 0;

560 fail:

561 av_packet_free_side_data(dst);

562 return ret;

563 }

564

565 void av_packet_move_ref(AVPacket *dst, AVPacket *src)

566 {

567 *dst = *src;

568 av_init_packet(src);

569 }

570

571 void av_packet_rescale_ts(AVPacket *pkt, AVRational src_tb, AVRational dst_tb)

572 {

573 if (pkt->pts != AV_NOPTS_VALUE)

574 pkt->pts = av_rescale_q(pkt->pts, src_tb, dst_tb);

575 if (pkt->dts != AV_NOPTS_VALUE)

576 pkt->dts = av_rescale_q(pkt->dts, src_tb, dst_tb);

577 if (pkt->duration > 0)

578 pkt->duration = av_rescale_q(pkt->duration, src_tb, dst_tb);

579 if (pkt->convergence_duration > 0)

580 pkt->convergence_duration = av_rescale_q(pkt->convergence_duration, src_tb, dst_tb);

581 }

Generated on Sun Mar 8 2015 02:34:49 for FFmpeg by doxygen 1.8.2