FFmpeg  2.1.1
avpacket.c
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1 /*
2  * AVPacket functions for libavcodec
3  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
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  */
21 
22 #include <string.h>
23 
24 #include "libavutil/avassert.h"
25 #include "libavutil/common.h"
26 #include "libavutil/internal.h"
27 #include "libavutil/mem.h"
28 #include "avcodec.h"
29 #include "bytestream.h"
30 #include "internal.h"
31 
32 #if FF_API_DESTRUCT_PACKET
33 
35 {
36  av_free(pkt->data);
37  pkt->data = NULL;
38  pkt->size = 0;
39 }
40 
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
48 
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
60  pkt->destruct = NULL;
62 #endif
63  pkt->buf = NULL;
64  pkt->side_data = NULL;
65  pkt->side_data_elems = 0;
66 }
67 
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);
73 
75  if (ret < 0)
76  return ret;
77 
78  memset((*buf)->data + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
79 
80  return 0;
81 }
82 
84 {
85  AVBufferRef *buf = NULL;
86  int ret = packet_alloc(&buf, size);
87  if (ret < 0)
88  return ret;
89 
90  av_init_packet(pkt);
91  pkt->buf = buf;
92  pkt->data = buf->data;
93  pkt->size = size;
94 #if FF_API_DESTRUCT_PACKET
96  pkt->destruct = dummy_destruct_packet;
98 #endif
99 
100  return 0;
101 }
102 
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
133  pkt->destruct = dummy_destruct_packet;
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 
145 {
146  if (size >= INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE)
147  return AVERROR(EINVAL);
148 
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
158  pkt->destruct = dummy_destruct_packet;
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, 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
208  pkt->destruct = dummy_destruct_packet;
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 
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  return 0;
241 
242 failed_alloc:
243  av_free_packet(pkt);
244  return AVERROR(ENOMEM);
245 }
246 
248 {
249  AVPacket tmp_pkt;
250 
252  if (!pkt->buf && pkt->data
254  && !pkt->destruct
255 #endif
256  ) {
258  tmp_pkt = *pkt;
259  return copy_packet_data(pkt, &tmp_pkt, 1);
260  }
261  return 0;
262 }
263 
265 {
266  *dst = *src;
267  return copy_packet_data(dst, src, 0);
268 }
269 
271 {
272  int i;
273  for (i = 0; i < pkt->side_data_elems; i++)
274  av_free(pkt->side_data[i].data);
275  av_freep(&pkt->side_data);
276  pkt->side_data_elems = 0;
277 }
278 
280 {
281  if (pkt) {
283  if (pkt->buf)
284  av_buffer_unref(&pkt->buf);
285 #if FF_API_DESTRUCT_PACKET
286  else if (pkt->destruct)
287  pkt->destruct(pkt);
288  pkt->destruct = NULL;
289 #endif
291  pkt->data = NULL;
292  pkt->size = 0;
293 
295  }
296 }
297 
299  int size)
300 {
301  int elems = pkt->side_data_elems;
302 
303  if ((unsigned)elems + 1 > INT_MAX / sizeof(*pkt->side_data))
304  return NULL;
305  if ((unsigned)size > INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE)
306  return NULL;
307 
308  pkt->side_data = av_realloc(pkt->side_data,
309  (elems + 1) * sizeof(*pkt->side_data));
310  if (!pkt->side_data)
311  return NULL;
312 
314  if (!pkt->side_data[elems].data)
315  return NULL;
316  pkt->side_data[elems].size = size;
317  pkt->side_data[elems].type = type;
318  pkt->side_data_elems++;
319 
320  return pkt->side_data[elems].data;
321 }
322 
324  int *size)
325 {
326  int i;
327 
328  for (i = 0; i < pkt->side_data_elems; i++) {
329  if (pkt->side_data[i].type == type) {
330  if (size)
331  *size = pkt->side_data[i].size;
332  return pkt->side_data[i].data;
333  }
334  }
335  return NULL;
336 }
337 
338 #define FF_MERGE_MARKER 0x8c4d9d108e25e9feULL
339 
341  if(pkt->side_data_elems){
342  AVBufferRef *buf;
343  int i;
344  uint8_t *p;
345  uint64_t size= pkt->size + 8LL + FF_INPUT_BUFFER_PADDING_SIZE;
346  AVPacket old= *pkt;
347  for (i=0; i<old.side_data_elems; i++) {
348  size += old.side_data[i].size + 5LL;
349  }
350  if (size > INT_MAX)
351  return AVERROR(EINVAL);
352  buf = av_buffer_alloc(size);
353  if (!buf)
354  return AVERROR(ENOMEM);
355  pkt->buf = buf;
356  pkt->data = p = buf->data;
357 #if FF_API_DESTRUCT_PACKET
359  pkt->destruct = dummy_destruct_packet;
361 #endif
362  pkt->size = size - FF_INPUT_BUFFER_PADDING_SIZE;
363  bytestream_put_buffer(&p, old.data, old.size);
364  for (i=old.side_data_elems-1; i>=0; i--) {
365  bytestream_put_buffer(&p, old.side_data[i].data, old.side_data[i].size);
366  bytestream_put_be32(&p, old.side_data[i].size);
367  *p++ = old.side_data[i].type | ((i==old.side_data_elems-1)*128);
368  }
369  bytestream_put_be64(&p, FF_MERGE_MARKER);
370  av_assert0(p-pkt->data == pkt->size);
371  memset(p, 0, FF_INPUT_BUFFER_PADDING_SIZE);
372  av_free_packet(&old);
373  pkt->side_data_elems = 0;
374  pkt->side_data = NULL;
375  return 1;
376  }
377  return 0;
378 }
379 
381  if (!pkt->side_data_elems && pkt->size >12 && AV_RB64(pkt->data + pkt->size - 8) == FF_MERGE_MARKER){
382  int i;
383  unsigned int size, orig_pktsize = pkt->size;
384  uint8_t *p;
385 
386  p = pkt->data + pkt->size - 8 - 5;
387  for (i=1; ; i++){
388  size = AV_RB32(p);
389  if (size>INT_MAX || p - pkt->data < size)
390  return 0;
391  if (p[4]&128)
392  break;
393  p-= size+5;
394  }
395 
396  pkt->side_data = av_malloc(i * sizeof(*pkt->side_data));
397  if (!pkt->side_data)
398  return AVERROR(ENOMEM);
399 
400  p= pkt->data + pkt->size - 8 - 5;
401  for (i=0; ; i++){
402  size= AV_RB32(p);
403  av_assert0(size<=INT_MAX && p - pkt->data >= size);
405  pkt->side_data[i].size = size;
406  pkt->side_data[i].type = p[4]&127;
407  if (!pkt->side_data[i].data)
408  return AVERROR(ENOMEM);
409  memcpy(pkt->side_data[i].data, p-size, size);
410  pkt->size -= size + 5;
411  if(p[4]&128)
412  break;
413  p-= size+5;
414  }
415  pkt->size -= 8;
416  /* FFMIN() prevents overflow in case the packet wasn't allocated with
417  * proper padding.
418  * If the side data is smaller than the buffer padding size, the
419  * remaining bytes should have already been filled with zeros by the
420  * original packet allocation anyway. */
421  memset(pkt->data + pkt->size, 0,
422  FFMIN(orig_pktsize - pkt->size, FF_INPUT_BUFFER_PADDING_SIZE));
423  pkt->side_data_elems = i+1;
424  return 1;
425  }
426  return 0;
427 }
428 
430  int size)
431 {
432  int i;
433 
434  for (i = 0; i < pkt->side_data_elems; i++) {
435  if (pkt->side_data[i].type == type) {
436  if (size > pkt->side_data[i].size)
437  return AVERROR(ENOMEM);
438  pkt->side_data[i].size = size;
439  return 0;
440  }
441  }
442  return AVERROR(ENOENT);
443 }
444 
446 {
447  int i;
448 
449  dst->pts = src->pts;
450  dst->dts = src->dts;
451  dst->pos = src->pos;
452  dst->duration = src->duration;
454  dst->flags = src->flags;
455  dst->stream_index = src->stream_index;
456  dst->side_data_elems = src->side_data_elems;
457 
458  for (i = 0; i < src->side_data_elems; i++) {
459  enum AVPacketSideDataType type = src->side_data[i].type;
460  int size = src->side_data[i].size;
461  uint8_t *src_data = src->side_data[i].data;
462  uint8_t *dst_data = av_packet_new_side_data(dst, type, size);
463 
464  if (!dst_data) {
466  return AVERROR(ENOMEM);
467  }
468  memcpy(dst_data, src_data, size);
469  }
470 
471  return 0;
472 }
473 
475 {
477  av_buffer_unref(&pkt->buf);
478  av_init_packet(pkt);
479  pkt->data = NULL;
480  pkt->size = 0;
481 }
482 
484 {
485  int ret;
486 
487  ret = av_packet_copy_props(dst, src);
488  if (ret < 0)
489  return ret;
490 
491  if (!src->buf) {
492  ret = packet_alloc(&dst->buf, src->size);
493  if (ret < 0)
494  goto fail;
495  memcpy(dst->buf->data, src->data, src->size);
496  } else
497  dst->buf = av_buffer_ref(src->buf);
498 
499  dst->size = src->size;
500  dst->data = dst->buf->data;
501  return 0;
502 fail:
504  return ret;
505 }
506 
508 {
509  *dst = *src;
510  av_init_packet(src);
511 }
#define DUP_DATA(dst, src, size, padding, ALLOC)
Definition: avpacket.c:172
AVPacketSideDataType
Definition: avcodec.h:918
void av_buffer_unref(AVBufferRef **buf)
Free a given reference and automatically free the buffer if there are no more references to it...
Definition: buffer.c:105
int size
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:279
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1092
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:103
#define ALLOC_MALLOC(data, size)
Definition: avpacket.c:165
int size
Definition: avcodec.h:1064
int av_copy_packet(AVPacket *dst, AVPacket *src)
Copy packet, including contents.
Definition: avpacket.c:264
#define ALLOC_BUF(data, size)
Definition: avpacket.c:166
int av_dup_packet(AVPacket *pkt)
Definition: avpacket.c:247
AVBufferRef * buf
A reference to the reference-counted buffer where the packet data is stored.
Definition: avcodec.h:1046
void av_freep(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:234
uint8_t
attribute_deprecated void(* destruct)(struct AVPacket *)
Definition: avcodec.h:1088
int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size)
Initialize a reference-counted packet from av_malloc()ed data.
Definition: avpacket.c:144
AVBufferRef * av_buffer_create(uint8_t *data, int size, void(*free)(void *opaque, uint8_t *data), void *opaque, int flags)
Create an AVBuffer from an existing array.
Definition: buffer.c:27
const char data[16]
Definition: mxf.c:68
void av_packet_move_ref(AVPacket *dst, AVPacket *src)
Move every field in src to dst and reset src.
Definition: avpacket.c:507
struct AVPacket::@25 * side_data
Additional packet data that can be provided by the container.
int duration
Duration of this packet in AVStream-&gt;time_base units, 0 if unknown.
Definition: avcodec.h:1085
void av_buffer_default_free(void *opaque, uint8_t *data)
Default free callback, which calls av_free() on the buffer data.
Definition: buffer.c:60
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:83
int av_copy_packet_side_data(AVPacket *dst, AVPacket *src)
Copy packet side data.
Definition: avpacket.c:223
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:219
void av_packet_free_side_data(AVPacket *pkt)
Convenience function to free all the side data stored.
Definition: avpacket.c:270
int64_t convergence_duration
Time difference in AVStream-&gt;time_base units from the pts of this packet to the point at which the ou...
Definition: avcodec.h:1111
static int copy_packet_data(AVPacket *pkt, AVPacket *src, int dup)
Definition: avpacket.c:193
int side_data_elems
Definition: avcodec.h:1079
int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int size)
Shrink the already allocated side data buffer.
Definition: avpacket.c:429
int av_buffer_realloc(AVBufferRef **buf, int size)
Reallocate a given buffer.
Definition: buffer.c:156
Libavcodec external API header.
uint8_t * av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int size)
Allocate new information of a packet.
Definition: avpacket.c:298
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1069
int av_packet_merge_side_data(AVPacket *pkt)
Definition: avpacket.c:340
goto fail
Definition: avfilter.c:963
common internal API header
#define FF_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:580
int av_packet_copy_props(AVPacket *dst, const AVPacket *src)
Copy only &quot;properties&quot; fields from src to dst.
Definition: avpacket.c:445
uint8_t * data
The data buffer.
Definition: buffer.h:89
void * av_realloc(void *ptr, size_t size) 1(2)
Allocate or reallocate a block of memory.
Definition: mem.c:141
ret
Definition: avfilter.c:961
uint8_t * av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:323
static int packet_alloc(AVBufferRef **buf, int size)
Definition: avpacket.c:68
void * av_malloc(size_t size) av_malloc_attrib 1(1)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:73
#define FFMIN(a, b)
Definition: avcodec.h:925
int av_packet_split_side_data(AVPacket *pkt)
Definition: avpacket.c:380
#define AV_RB64(x)
Definition: intreadwrite.h:292
attribute_deprecated void av_destruct_packet(AVPacket *pkt)
Default packet destructor.
#define FF_API_DESTRUCT_PACKET
Definition: version.h:83
AVBufferRef * av_buffer_alloc(int size)
Allocate an AVBuffer of the given size using av_malloc().
Definition: buffer.c:65
AVS_Value src
Definition: avisynth_c.h:523
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:474
void * buf
Definition: avisynth_c.h:594
uint8_t * data
Definition: avcodec.h:1063
#define type
#define FF_MERGE_MARKER
Definition: avpacket.c:338
A reference to a data buffer.
Definition: buffer.h:81
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:78
common internal api header.
int av_grow_packet(AVPacket *pkt, int grow_by)
Increase packet size, correctly zeroing padding.
Definition: avpacket.c:111
void av_init_packet(AVPacket *pkt)
Initialize optional fields of a packet with default values.
Definition: avpacket.c:49
static av_always_inline void bytestream_put_buffer(uint8_t **b, const uint8_t *src, unsigned int size)
Definition: bytestream.h:340
int av_packet_ref(AVPacket *dst, AVPacket *src)
Setup a new reference to the data described by a given packet.
Definition: avpacket.c:483
#define AV_RB32(x)
Definition: intreadwrite.h:258
AVBufferRef * av_buffer_ref(AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:91
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:79
#define AVERROR(e)
int64_t dts
Decompression timestamp in AVStream-&gt;time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1062
enum AVPacketSideDataType type
Definition: avcodec.h:1077
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
static AVPacket pkt
Definition: demuxing.c:52
int stream_index
Definition: avcodec.h:1065
This structure stores compressed data.
Definition: avcodec.h:1040
int64_t pts
Presentation timestamp in AVStream-&gt;time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1056
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avcodec.h:2278
void * av_mallocz(size_t size) av_malloc_attrib 1(1)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:241