aboutsummaryrefslogtreecommitdiffstats
path: root/libavcodec/avpacket.c
blob: 002fa0f51381b8e28882019e05df8c35b06a309a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
/*
 * AVPacket functions for libavcodec
 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
 *
 * 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
 */

#include <string.h>

#include "libavutil/avassert.h"
#include "libavutil/common.h"
#include "libavutil/internal.h"
#include "libavutil/mathematics.h"
#include "libavutil/mem.h"
#include "avcodec.h"
#include "bytestream.h"
#include "internal.h"

void av_init_packet(AVPacket *pkt)
{
    pkt->pts                  = AV_NOPTS_VALUE;
    pkt->dts                  = AV_NOPTS_VALUE;
    pkt->pos                  = -1;
    pkt->duration             = 0;
#if FF_API_CONVERGENCE_DURATION
FF_DISABLE_DEPRECATION_WARNINGS
    pkt->convergence_duration = 0;
FF_ENABLE_DEPRECATION_WARNINGS
#endif
    pkt->flags                = 0;
    pkt->stream_index         = 0;
    pkt->buf                  = NULL;
    pkt->side_data            = NULL;
    pkt->side_data_elems      = 0;
}

AVPacket *av_packet_alloc(void)
{
    AVPacket *pkt = av_mallocz(sizeof(AVPacket));
    if (!pkt)
        return pkt;

    av_packet_unref(pkt);

    return pkt;
}

void av_packet_free(AVPacket **pkt)
{
    if (!pkt || !*pkt)
        return;

    av_packet_unref(*pkt);
    av_freep(pkt);
}

static int packet_alloc(AVBufferRef **buf, int size)
{
    int ret;
    if (size < 0 || size >= INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE)
        return AVERROR(EINVAL);

    ret = av_buffer_realloc(buf, size + AV_INPUT_BUFFER_PADDING_SIZE);
    if (ret < 0)
        return ret;

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

    return 0;
}

int av_new_packet(AVPacket *pkt, int size)
{
    AVBufferRef *buf = NULL;
    int ret = packet_alloc(&buf, size);
    if (ret < 0)
        return ret;

    av_init_packet(pkt);
    pkt->buf      = buf;
    pkt->data     = buf->data;
    pkt->size     = size;

    return 0;
}

void av_shrink_packet(AVPacket *pkt, int size)
{
    if (pkt->size <= size)
        return;
    pkt->size = size;
    memset(pkt->data + size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
}

int av_grow_packet(AVPacket *pkt, int grow_by)
{
    int new_size;
    av_assert0((unsigned)pkt->size <= INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE);
    if ((unsigned)grow_by >
        INT_MAX - (pkt->size + AV_INPUT_BUFFER_PADDING_SIZE))
        return -1;

    new_size = pkt->size + grow_by + AV_INPUT_BUFFER_PADDING_SIZE;
    if (pkt->buf) {
        size_t data_offset;
        uint8_t *old_data = pkt->data;
        if (pkt->data == NULL) {
            data_offset = 0;
            pkt->data = pkt->buf->data;
        } else {
            data_offset = pkt->data - pkt->buf->data;
            if (data_offset > INT_MAX - new_size)
                return -1;
        }

        if (new_size + data_offset > pkt->buf->size) {
            int ret = av_buffer_realloc(&pkt->buf, new_size + data_offset);
            if (ret < 0) {
                pkt->data = old_data;
                return ret;
            }
            pkt->data = pkt->buf->data + data_offset;
        }
    } else {
        pkt->buf = av_buffer_alloc(new_size);
        if (!pkt->buf)
            return AVERROR(ENOMEM);
        if (pkt->size > 0)
            memcpy(pkt->buf->data, pkt->data, pkt->size);
        pkt->data = pkt->buf->data;
    }
    pkt->size += grow_by;
    memset(pkt->data + pkt->size, 0, AV_INPUT_BUFFER_PADDING_SIZE);

    return 0;
}

int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size)
{
    if (size >= INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE)
        return AVERROR(EINVAL);

    pkt->buf = av_buffer_create(data, size + AV_INPUT_BUFFER_PADDING_SIZE,
                                av_buffer_default_free, NULL, 0);
    if (!pkt->buf)
        return AVERROR(ENOMEM);

    pkt->data = data;
    pkt->size = size;

    return 0;
}

#if FF_API_AVPACKET_OLD_API
FF_DISABLE_DEPRECATION_WARNINGS
#define ALLOC_MALLOC(data, size) data = av_malloc(size)
#define ALLOC_BUF(data, size)                \
do {                                         \
    av_buffer_realloc(&pkt->buf, size);      \
    data = pkt->buf ? pkt->buf->data : NULL; \
} while (0)

#define DUP_DATA(dst, src, size, padding, ALLOC)                        \
    do {                                                                \
        void *data;                                                     \
        if (padding) {                                                  \
            if ((unsigned)(size) >                                      \
                (unsigned)(size) + AV_INPUT_BUFFER_PADDING_SIZE)        \
                goto failed_alloc;                                      \
            ALLOC(data, size + AV_INPUT_BUFFER_PADDING_SIZE);           \
        } else {                                                        \
            ALLOC(data, size);                                          \
        }                                                               \
        if (!data)                                                      \
            goto failed_alloc;                                          \
        memcpy(data, src, size);                                        \
        if (padding)                                                    \
            memset((uint8_t *)data + size, 0,                           \
                   AV_INPUT_BUFFER_PADDING_SIZE);                       \
        dst = data;                                                     \
    } while (0)

/* Makes duplicates of data, side_data, but does not copy any other fields */
static int copy_packet_data(AVPacket *pkt, const AVPacket *src, int dup)
{
    pkt->data      = NULL;
    pkt->side_data = NULL;
    pkt->side_data_elems = 0;
    if (pkt->buf) {
        AVBufferRef *ref = av_buffer_ref(src->buf);
        if (!ref)
            return AVERROR(ENOMEM);
        pkt->buf  = ref;
        pkt->data = ref->data;
    } else {
        DUP_DATA(pkt->data, src->data, pkt->size, 1, ALLOC_BUF);
    }
    if (src->side_data_elems && dup) {
        pkt->side_data = src->side_data;
        pkt->side_data_elems = src->side_data_elems;
    }
    if (src->side_data_elems && !dup) {
        return av_copy_packet_side_data(pkt, src);
    }
    return 0;

failed_alloc:
    av_packet_unref(pkt);
    return AVERROR(ENOMEM);
}

int av_copy_packet_side_data(AVPacket *pkt, const AVPacket *src)
{
    if (src->side_data_elems) {
        int i;
        DUP_DATA(pkt->side_data, src->side_data,
                src->side_data_elems * sizeof(*src->side_data), 0, ALLOC_MALLOC);
        if (src != pkt) {
            memset(pkt->side_data, 0,
                   src->side_data_elems * sizeof(*src->side_data));
        }
        for (i = 0; i < src->side_data_elems; i++) {
            DUP_DATA(pkt->side_data[i].data, src->side_data[i].data,
                    src->side_data[i].size, 1, ALLOC_MALLOC);
            pkt->side_data[i].size = src->side_data[i].size;
            pkt->side_data[i].type = src->side_data[i].type;
        }
    }
    pkt->side_data_elems = src->side_data_elems;
    return 0;

failed_alloc:
    av_packet_unref(pkt);
    return AVERROR(ENOMEM);
}

int av_dup_packet(AVPacket *pkt)
{
    AVPacket tmp_pkt;

    if (!pkt->buf && pkt->data) {
        tmp_pkt = *pkt;
        return copy_packet_data(pkt, &tmp_pkt, 1);
    }
    return 0;
}

int av_copy_packet(AVPacket *dst, const AVPacket *src)
{
    *dst = *src;
    return copy_packet_data(dst, src, 0);
}
FF_ENABLE_DEPRECATION_WARNINGS
#endif

void av_packet_free_side_data(AVPacket *pkt)
{
    int i;
    for (i = 0; i < pkt->side_data_elems; i++)
        av_freep(&pkt->side_data[i].data);
    av_freep(&pkt->side_data);
    pkt->side_data_elems = 0;
}

#if FF_API_AVPACKET_OLD_API
FF_DISABLE_DEPRECATION_WARNINGS
void av_free_packet(AVPacket *pkt)
{
    if (pkt) {
        if (pkt->buf)
            av_buffer_unref(&pkt->buf);
        pkt->data            = NULL;
        pkt->size            = 0;

        av_packet_free_side_data(pkt);
    }
}
FF_ENABLE_DEPRECATION_WARNINGS
#endif

int av_packet_add_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
                            uint8_t *data, size_t size)
{
    AVPacketSideData *tmp;
    int i, elems = pkt->side_data_elems;

    for (i = 0; i < elems; i++) {
        AVPacketSideData *sd = &pkt->side_data[i];

        if (sd->type == type) {
            av_free(sd->data);
            sd->data = data;
            sd->size = size;
            return 0;
        }
    }

    if ((unsigned)elems + 1 > AV_PKT_DATA_NB)
        return AVERROR(ERANGE);

    tmp = av_realloc(pkt->side_data, (elems + 1) * sizeof(*tmp));
    if (!tmp)
        return AVERROR(ENOMEM);

    pkt->side_data = tmp;
    pkt->side_data[elems].data = data;
    pkt->side_data[elems].size = size;
    pkt->side_data[elems].type = type;
    pkt->side_data_elems++;

    return 0;
}


uint8_t *av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
                                 int size)
{
    int ret;
    uint8_t *data;

    if ((unsigned)size > INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE)
        return NULL;
    data = av_mallocz(size + AV_INPUT_BUFFER_PADDING_SIZE);
    if (!data)
        return NULL;

    ret = av_packet_add_side_data(pkt, type, data, size);
    if (ret < 0) {
        av_freep(&data);
        return NULL;
    }

    return data;
}

uint8_t *av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type,
                                 int *size)
{
    int i;

    for (i = 0; i < pkt->side_data_elems; i++) {
        if (pkt->side_data[i].type == type) {
            if (size)
                *size = pkt->side_data[i].size;
            return pkt->side_data[i].data;
        }
    }
    if (size)
        *size = 0;
    return NULL;
}

const char *av_packet_side_data_name(enum AVPacketSideDataType type)
{
    switch(type) {
    case AV_PKT_DATA_PALETTE:                    return "Palette";
    case AV_PKT_DATA_NEW_EXTRADATA:              return "New Extradata";
    case AV_PKT_DATA_PARAM_CHANGE:               return "Param Change";
    case AV_PKT_DATA_H263_MB_INFO:               return "H263 MB Info";
    case AV_PKT_DATA_REPLAYGAIN:                 return "Replay Gain";
    case AV_PKT_DATA_DISPLAYMATRIX:              return "Display Matrix";
    case AV_PKT_DATA_STEREO3D:                   return "Stereo 3D";
    case AV_PKT_DATA_AUDIO_SERVICE_TYPE:         return "Audio Service Type";
    case AV_PKT_DATA_QUALITY_STATS:              return "Quality stats";
    case AV_PKT_DATA_FALLBACK_TRACK:             return "Fallback track";
    case AV_PKT_DATA_CPB_PROPERTIES:             return "CPB properties";
    case AV_PKT_DATA_SKIP_SAMPLES:               return "Skip Samples";
    case AV_PKT_DATA_JP_DUALMONO:                return "JP Dual Mono";
    case AV_PKT_DATA_STRINGS_METADATA:           return "Strings Metadata";
    case AV_PKT_DATA_SUBTITLE_POSITION:          return "Subtitle Position";
    case AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL:   return "Matroska BlockAdditional";
    case AV_PKT_DATA_WEBVTT_IDENTIFIER:          return "WebVTT ID";
    case AV_PKT_DATA_WEBVTT_SETTINGS:            return "WebVTT Settings";
    case AV_PKT_DATA_METADATA_UPDATE:            return "Metadata Update";
    case AV_PKT_DATA_MPEGTS_STREAM_ID:           return "MPEGTS Stream ID";
    case AV_PKT_DATA_MASTERING_DISPLAY_METADATA: return "Mastering display metadata";
    case AV_PKT_DATA_CONTENT_LIGHT_LEVEL:        return "Content light level metadata";
    case AV_PKT_DATA_SPHERICAL:                  return "Spherical Mapping";
    case AV_PKT_DATA_A53_CC:                     return "A53 Closed Captions";
    case AV_PKT_DATA_ENCRYPTION_INIT_INFO:       return "Encryption initialization data";
    case AV_PKT_DATA_ENCRYPTION_INFO:            return "Encryption info";
    case AV_PKT_DATA_AFD:                        return "Active Format Description data";
    }
    return NULL;
}

#if FF_API_MERGE_SD_API

#define FF_MERGE_MARKER 0x8c4d9d108e25e9feULL

int av_packet_merge_side_data(AVPacket *pkt){
    if(pkt->side_data_elems){
        AVBufferRef *buf;
        int i;
        uint8_t *p;
        uint64_t size= pkt->size + 8LL + AV_INPUT_BUFFER_PADDING_SIZE;
        AVPacket old= *pkt;
        for (i=0; i<old.side_data_elems; i++) {
            size += old.side_data[i].size + 5LL;
        }
        if (size > INT_MAX)
            return AVERROR(EINVAL);
        buf = av_buffer_alloc(size);
        if (!buf)
            return AVERROR(ENOMEM);
        pkt->buf = buf;
        pkt->data = p = buf->data;
        pkt->size = size - AV_INPUT_BUFFER_PADDING_SIZE;
        bytestream_put_buffer(&p, old.data, old.size);
        for (i=old.side_data_elems-1; i>=0; i--) {
            bytestream_put_buffer(&p, old.side_data[i].data, old.side_data[i].size);
            bytestream_put_be32(&p, old.side_data[i].size);
            *p++ = old.side_data[i].type | ((i==old.side_data_elems-1)*128);
        }
        bytestream_put_be64(&p, FF_MERGE_MARKER);
        av_assert0(p-pkt->data == pkt->size);
        memset(p, 0, AV_INPUT_BUFFER_PADDING_SIZE);
        av_packet_unref(&old);
        pkt->side_data_elems = 0;
        pkt->side_data = NULL;
        return 1;
    }
    return 0;
}

int av_packet_split_side_data(AVPacket *pkt){
    if (!pkt->side_data_elems && pkt->size >12 && AV_RB64(pkt->data + pkt->size - 8) == FF_MERGE_MARKER){
        int i;
        unsigned int size;
        uint8_t *p;

        p = pkt->data + pkt->size - 8 - 5;
        for (i=1; ; i++){
            size = AV_RB32(p);
            if (size>INT_MAX - 5 || p - pkt->data < size)
                return 0;
            if (p[4]&128)
                break;
            if (p - pkt->data < size + 5)
                return 0;
            p-= size+5;
        }

        if (i > AV_PKT_DATA_NB)
            return AVERROR(ERANGE);

        pkt->side_data = av_malloc_array(i, sizeof(*pkt->side_data));
        if (!pkt->side_data)
            return AVERROR(ENOMEM);

        p= pkt->data + pkt->size - 8 - 5;
        for (i=0; ; i++){
            size= AV_RB32(p);
            av_assert0(size<=INT_MAX - 5 && p - pkt->data >= size);
            pkt->side_data[i].data = av_mallocz(size + AV_INPUT_BUFFER_PADDING_SIZE);
            pkt->side_data[i].size = size;
            pkt->side_data[i].type = p[4]&127;
            if (!pkt->side_data[i].data)
                return AVERROR(ENOMEM);
            memcpy(pkt->side_data[i].data, p-size, size);
            pkt->size -= size + 5;
            if(p[4]&128)
                break;
            p-= size+5;
        }
        pkt->size -= 8;
        pkt->side_data_elems = i+1;
        return 1;
    }
    return 0;
}
#endif

uint8_t *av_packet_pack_dictionary(AVDictionary *dict, int *size)
{
    AVDictionaryEntry *t = NULL;
    uint8_t *data = NULL;
    *size = 0;

    if (!dict)
        return NULL;

    while ((t = av_dict_get(dict, "", t, AV_DICT_IGNORE_SUFFIX))) {
        const size_t keylen   = strlen(t->key);
        const size_t valuelen = strlen(t->value);
        const size_t new_size = *size + keylen + 1 + valuelen + 1;
        uint8_t *const new_data = av_realloc(data, new_size);

        if (!new_data)
            goto fail;
        data = new_data;
        if (new_size > INT_MAX)
            goto fail;

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

        *size = new_size;
    }

    return data;

fail:
    av_freep(&data);
    *size = 0;
    return NULL;
}

int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict)
{
    const uint8_t *end = data + size;
    int ret = 0;

    if (!dict || !data || !size)
        return ret;
    if (size && end[-1])
        return AVERROR_INVALIDDATA;
    while (data < end) {
        const uint8_t *key = data;
        const uint8_t *val = data + strlen(key) + 1;

        if (val >= end || !*key)
            return AVERROR_INVALIDDATA;

        ret = av_dict_set(dict, key, val, 0);
        if (ret < 0)
            break;
        data = val + strlen(val) + 1;
    }

    return ret;
}

int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
                               int size)
{
    int i;

    for (i = 0; i < pkt->side_data_elems; i++) {
        if (pkt->side_data[i].type == type) {
            if (size > pkt->side_data[i].size)
                return AVERROR(ENOMEM);
            pkt->side_data[i].size = size;
            return 0;
        }
    }
    return AVERROR(ENOENT);
}

int av_packet_copy_props(AVPacket *dst, const AVPacket *src)
{
    int i;

    dst->pts                  = src->pts;
    dst->dts                  = src->dts;
    dst->pos                  = src->pos;
    dst->duration             = src->duration;
#if FF_API_CONVERGENCE_DURATION
FF_DISABLE_DEPRECATION_WARNINGS
    dst->convergence_duration = src->convergence_duration;
FF_ENABLE_DEPRECATION_WARNINGS
#endif
    dst->flags                = src->flags;
    dst->stream_index         = src->stream_index;

    dst->side_data            = NULL;
    dst->side_data_elems      = 0;
    for (i = 0; i < src->side_data_elems; i++) {
         enum AVPacketSideDataType type = src->side_data[i].type;
         int size          = src->side_data[i].size;
         uint8_t *src_data = src->side_data[i].data;
         uint8_t *dst_data = av_packet_new_side_data(dst, type, size);

        if (!dst_data) {
            av_packet_free_side_data(dst);
            return AVERROR(ENOMEM);
        }
        memcpy(dst_data, src_data, size);
    }

    return 0;
}

void av_packet_unref(AVPacket *pkt)
{
    av_packet_free_side_data(pkt);
    av_buffer_unref(&pkt->buf);
    av_init_packet(pkt);
    pkt->data = NULL;
    pkt->size = 0;
}

int av_packet_ref(AVPacket *dst, const AVPacket *src)
{
    int ret;

    ret = av_packet_copy_props(dst, src);
    if (ret < 0)
        return ret;

    if (!src->buf) {
        ret = packet_alloc(&dst->buf, src->size);
        if (ret < 0)
            goto fail;
        if (src->size)
            memcpy(dst->buf->data, src->data, src->size);

        dst->data = dst->buf->data;
    } else {
        dst->buf = av_buffer_ref(src->buf);
        if (!dst->buf) {
            ret = AVERROR(ENOMEM);
            goto fail;
        }
        dst->data = src->data;
    }

    dst->size = src->size;

    return 0;
fail:
    av_packet_free_side_data(dst);
    return ret;
}

AVPacket *av_packet_clone(const AVPacket *src)
{
    AVPacket *ret = av_packet_alloc();

    if (!ret)
        return ret;

    if (av_packet_ref(ret, src))
        av_packet_free(&ret);

    return ret;
}

void av_packet_move_ref(AVPacket *dst, AVPacket *src)
{
    *dst = *src;
    av_init_packet(src);
    src->data = NULL;
    src->size = 0;
}

int av_packet_make_refcounted(AVPacket *pkt)
{
    int ret;

    if (pkt->buf)
        return 0;

    ret = packet_alloc(&pkt->buf, pkt->size);
    if (ret < 0)
        return ret;
    if (pkt->size)
        memcpy(pkt->buf->data, pkt->data, pkt->size);

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

    return 0;
}

int av_packet_make_writable(AVPacket *pkt)
{
    AVBufferRef *buf = NULL;
    int ret;

    if (pkt->buf && av_buffer_is_writable(pkt->buf))
        return 0;

    ret = packet_alloc(&buf, pkt->size);
    if (ret < 0)
        return ret;
    if (pkt->size)
        memcpy(buf->data, pkt->data, pkt->size);

    av_buffer_unref(&pkt->buf);
    pkt->buf  = buf;
    pkt->data = buf->data;

    return 0;
}

void av_packet_rescale_ts(AVPacket *pkt, AVRational src_tb, AVRational dst_tb)
{
    if (pkt->pts != AV_NOPTS_VALUE)
        pkt->pts = av_rescale_q(pkt->pts, src_tb, dst_tb);
    if (pkt->dts != AV_NOPTS_VALUE)
        pkt->dts = av_rescale_q(pkt->dts, src_tb, dst_tb);
    if (pkt->duration > 0)
        pkt->duration = av_rescale_q(pkt->duration, src_tb, dst_tb);
#if FF_API_CONVERGENCE_DURATION
FF_DISABLE_DEPRECATION_WARNINGS
    if (pkt->convergence_duration > 0)
        pkt->convergence_duration = av_rescale_q(pkt->convergence_duration, src_tb, dst_tb);
FF_ENABLE_DEPRECATION_WARNINGS
#endif
}

int ff_side_data_set_encoder_stats(AVPacket *pkt, int quality, int64_t *error, int error_count, int pict_type)
{
    uint8_t *side_data;
    int side_data_size;
    int i;

    side_data = av_packet_get_side_data(pkt, AV_PKT_DATA_QUALITY_STATS, &side_data_size);
    if (!side_data) {
        side_data_size = 4+4+8*error_count;
        side_data = av_packet_new_side_data(pkt, AV_PKT_DATA_QUALITY_STATS,
                                            side_data_size);
    }

    if (!side_data || side_data_size < 4+4+8*error_count)
        return AVERROR(ENOMEM);

    AV_WL32(side_data   , quality  );
    side_data[4] = pict_type;
    side_data[5] = error_count;
    for (i = 0; i<error_count; i++)
        AV_WL64(side_data+8 + 8*i , error[i]);

    return 0;
}