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nutdec.c
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1 /*
2  * "NUT" Container Format demuxer
3  * Copyright (c) 2004-2006 Michael Niedermayer
4  * Copyright (c) 2003 Alex Beregszaszi
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "libavutil/avstring.h"
24 #include "libavutil/avassert.h"
25 #include "libavutil/bswap.h"
26 #include "libavutil/dict.h"
27 #include "libavutil/intreadwrite.h"
28 #include "libavutil/mathematics.h"
29 #include "libavutil/tree.h"
30 #include "libavcodec/bytestream.h"
31 #include "avio_internal.h"
32 #include "nut.h"
33 #include "riff.h"
34 
35 #define NUT_MAX_STREAMS 256 /* arbitrary sanity check value */
36 
37 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
38  int64_t *pos_arg, int64_t pos_limit);
39 
40 static int get_str(AVIOContext *bc, char *string, unsigned int maxlen)
41 {
42  unsigned int len = ffio_read_varlen(bc);
43 
44  if (len && maxlen)
45  avio_read(bc, string, FFMIN(len, maxlen));
46  while (len > maxlen) {
47  avio_r8(bc);
48  len--;
49  }
50 
51  if (maxlen)
52  string[FFMIN(len, maxlen - 1)] = 0;
53 
54  if (maxlen == len)
55  return -1;
56  else
57  return 0;
58 }
59 
60 static int64_t get_s(AVIOContext *bc)
61 {
62  int64_t v = ffio_read_varlen(bc) + 1;
63 
64  if (v & 1)
65  return -(v >> 1);
66  else
67  return (v >> 1);
68 }
69 
70 static uint64_t get_fourcc(AVIOContext *bc)
71 {
72  unsigned int len = ffio_read_varlen(bc);
73 
74  if (len == 2)
75  return avio_rl16(bc);
76  else if (len == 4)
77  return avio_rl32(bc);
78  else {
79  av_log(NULL, AV_LOG_ERROR, "Unsupported fourcc length %d\n", len);
80  return -1;
81  }
82 }
83 
84 #ifdef TRACE
85 static inline uint64_t get_v_trace(AVIOContext *bc, const char *file,
86  const char *func, int line)
87 {
88  uint64_t v = ffio_read_varlen(bc);
89 
90  av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n",
91  v, v, file, func, line);
92  return v;
93 }
94 
95 static inline int64_t get_s_trace(AVIOContext *bc, const char *file,
96  const char *func, int line)
97 {
98  int64_t v = get_s(bc);
99 
100  av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n",
101  v, v, file, func, line);
102  return v;
103 }
104 
105 static inline uint64_t get_4cc_trace(AVIOContext *bc, char *file,
106  char *func, int line)
107 {
108  uint64_t v = get_fourcc(bc);
109 
110  av_log(NULL, AV_LOG_DEBUG, "get_fourcc %5"PRId64" / %"PRIX64" in %s %s:%d\n",
111  v, v, file, func, line);
112  return v;
113 }
114 #define ffio_read_varlen(bc) get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
115 #define get_s(bc) get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
116 #define get_fourcc(bc) get_4cc_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
117 #endif
118 
120  int calculate_checksum, uint64_t startcode)
121 {
122  int64_t size;
123 // start = avio_tell(bc) - 8;
124 
125  startcode = av_be2ne64(startcode);
126  startcode = ff_crc04C11DB7_update(0, (uint8_t*) &startcode, 8);
127 
129  size = ffio_read_varlen(bc);
130  if (size > 4096)
131  avio_rb32(bc);
132  if (ffio_get_checksum(bc) && size > 4096)
133  return -1;
134 
135  ffio_init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
136 
137  return size;
138 }
139 
140 static uint64_t find_any_startcode(AVIOContext *bc, int64_t pos)
141 {
142  uint64_t state = 0;
143 
144  if (pos >= 0)
145  /* Note, this may fail if the stream is not seekable, but that should
146  * not matter, as in this case we simply start where we currently are */
147  avio_seek(bc, pos, SEEK_SET);
148  while (!url_feof(bc)) {
149  state = (state << 8) | avio_r8(bc);
150  if ((state >> 56) != 'N')
151  continue;
152  switch (state) {
153  case MAIN_STARTCODE:
154  case STREAM_STARTCODE:
155  case SYNCPOINT_STARTCODE:
156  case INFO_STARTCODE:
157  case INDEX_STARTCODE:
158  return state;
159  }
160  }
161 
162  return 0;
163 }
164 
165 /**
166  * Find the given startcode.
167  * @param code the startcode
168  * @param pos the start position of the search, or -1 if the current position
169  * @return the position of the startcode or -1 if not found
170  */
171 static int64_t find_startcode(AVIOContext *bc, uint64_t code, int64_t pos)
172 {
173  for (;;) {
174  uint64_t startcode = find_any_startcode(bc, pos);
175  if (startcode == code)
176  return avio_tell(bc) - 8;
177  else if (startcode == 0)
178  return -1;
179  pos = -1;
180  }
181 }
182 
183 static int nut_probe(AVProbeData *p)
184 {
185  int i;
186  uint64_t code = 0;
187 
188  for (i = 0; i < p->buf_size; i++) {
189  code = (code << 8) | p->buf[i];
190  if (code == MAIN_STARTCODE)
191  return AVPROBE_SCORE_MAX;
192  }
193  return 0;
194 }
195 
196 #define GET_V(dst, check) \
197  do { \
198  tmp = ffio_read_varlen(bc); \
199  if (!(check)) { \
200  av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp); \
201  return AVERROR_INVALIDDATA; \
202  } \
203  dst = tmp; \
204  } while (0)
205 
206 static int skip_reserved(AVIOContext *bc, int64_t pos)
207 {
208  pos -= avio_tell(bc);
209  if (pos < 0) {
210  avio_seek(bc, pos, SEEK_CUR);
211  return AVERROR_INVALIDDATA;
212  } else {
213  while (pos--)
214  avio_r8(bc);
215  return 0;
216  }
217 }
218 
220 {
221  AVFormatContext *s = nut->avf;
222  AVIOContext *bc = s->pb;
223  uint64_t tmp, end;
224  unsigned int stream_count;
225  int i, j, count;
226  int tmp_stream, tmp_mul, tmp_pts, tmp_size, tmp_res, tmp_head_idx;
227 
228  end = get_packetheader(nut, bc, 1, MAIN_STARTCODE);
229  end += avio_tell(bc);
230 
231  tmp = ffio_read_varlen(bc);
232  if (tmp < 2 && tmp > 4) {
233  av_log(s, AV_LOG_ERROR, "Version %"PRId64" not supported.\n",
234  tmp);
235  return AVERROR(ENOSYS);
236  }
237  nut->version = tmp;
238  if (nut->version > 3)
239  nut->minor_version = ffio_read_varlen(bc);
240 
241  GET_V(stream_count, tmp > 0 && tmp <= NUT_MAX_STREAMS);
242 
243  nut->max_distance = ffio_read_varlen(bc);
244  if (nut->max_distance > 65536) {
245  av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
246  nut->max_distance = 65536;
247  }
248 
249  GET_V(nut->time_base_count, tmp > 0 && tmp < INT_MAX / sizeof(AVRational));
250  nut->time_base = av_malloc(nut->time_base_count * sizeof(AVRational));
251  if (!nut->time_base)
252  return AVERROR(ENOMEM);
253 
254  for (i = 0; i < nut->time_base_count; i++) {
255  GET_V(nut->time_base[i].num, tmp > 0 && tmp < (1ULL << 31));
256  GET_V(nut->time_base[i].den, tmp > 0 && tmp < (1ULL << 31));
257  if (av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1) {
258  av_log(s, AV_LOG_ERROR, "time base invalid\n");
259  return AVERROR_INVALIDDATA;
260  }
261  }
262  tmp_pts = 0;
263  tmp_mul = 1;
264  tmp_stream = 0;
265  tmp_head_idx = 0;
266  for (i = 0; i < 256;) {
267  int tmp_flags = ffio_read_varlen(bc);
268  int tmp_fields = ffio_read_varlen(bc);
269 
270  if (tmp_fields > 0)
271  tmp_pts = get_s(bc);
272  if (tmp_fields > 1)
273  tmp_mul = ffio_read_varlen(bc);
274  if (tmp_fields > 2)
275  tmp_stream = ffio_read_varlen(bc);
276  if (tmp_fields > 3)
277  tmp_size = ffio_read_varlen(bc);
278  else
279  tmp_size = 0;
280  if (tmp_fields > 4)
281  tmp_res = ffio_read_varlen(bc);
282  else
283  tmp_res = 0;
284  if (tmp_fields > 5)
285  count = ffio_read_varlen(bc);
286  else
287  count = tmp_mul - tmp_size;
288  if (tmp_fields > 6)
289  get_s(bc);
290  if (tmp_fields > 7)
291  tmp_head_idx = ffio_read_varlen(bc);
292 
293  while (tmp_fields-- > 8)
294  ffio_read_varlen(bc);
295 
296  if (count == 0 || i + count > 256) {
297  av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
298  return AVERROR_INVALIDDATA;
299  }
300  if (tmp_stream >= stream_count) {
301  av_log(s, AV_LOG_ERROR, "illegal stream number\n");
302  return AVERROR_INVALIDDATA;
303  }
304 
305  for (j = 0; j < count; j++, i++) {
306  if (i == 'N') {
307  nut->frame_code[i].flags = FLAG_INVALID;
308  j--;
309  continue;
310  }
311  nut->frame_code[i].flags = tmp_flags;
312  nut->frame_code[i].pts_delta = tmp_pts;
313  nut->frame_code[i].stream_id = tmp_stream;
314  nut->frame_code[i].size_mul = tmp_mul;
315  nut->frame_code[i].size_lsb = tmp_size + j;
316  nut->frame_code[i].reserved_count = tmp_res;
317  nut->frame_code[i].header_idx = tmp_head_idx;
318  }
319  }
320  av_assert0(nut->frame_code['N'].flags == FLAG_INVALID);
321 
322  if (end > avio_tell(bc) + 4) {
323  int rem = 1024;
324  GET_V(nut->header_count, tmp < 128U);
325  nut->header_count++;
326  for (i = 1; i < nut->header_count; i++) {
327  uint8_t *hdr;
328  GET_V(nut->header_len[i], tmp > 0 && tmp < 256);
329  rem -= nut->header_len[i];
330  if (rem < 0) {
331  av_log(s, AV_LOG_ERROR, "invalid elision header\n");
332  return AVERROR_INVALIDDATA;
333  }
334  hdr = av_malloc(nut->header_len[i]);
335  if (!hdr)
336  return AVERROR(ENOMEM);
337  avio_read(bc, hdr, nut->header_len[i]);
338  nut->header[i] = hdr;
339  }
340  av_assert0(nut->header_len[0] == 0);
341  }
342 
343  if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
344  av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
345  return AVERROR_INVALIDDATA;
346  }
347 
348  nut->stream = av_calloc(stream_count, sizeof(StreamContext));
349  if (!nut->stream)
350  return AVERROR(ENOMEM);
351  for (i = 0; i < stream_count; i++)
352  avformat_new_stream(s, NULL);
353 
354  return 0;
355 }
356 
358 {
359  AVFormatContext *s = nut->avf;
360  AVIOContext *bc = s->pb;
361  StreamContext *stc;
362  int class, stream_id;
363  uint64_t tmp, end;
364  AVStream *st;
365 
366  end = get_packetheader(nut, bc, 1, STREAM_STARTCODE);
367  end += avio_tell(bc);
368 
369  GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
370  stc = &nut->stream[stream_id];
371  st = s->streams[stream_id];
372  if (!st)
373  return AVERROR(ENOMEM);
374 
375  class = ffio_read_varlen(bc);
376  tmp = get_fourcc(bc);
377  st->codec->codec_tag = tmp;
378  switch (class) {
379  case 0:
381  st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
384  0
385  },
386  tmp);
387  break;
388  case 1:
390  st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
393  0
394  },
395  tmp);
396  break;
397  case 2:
400  break;
401  case 3:
404  break;
405  default:
406  av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
407  return AVERROR(ENOSYS);
408  }
409  if (class < 3 && st->codec->codec_id == AV_CODEC_ID_NONE)
410  av_log(s, AV_LOG_ERROR,
411  "Unknown codec tag '0x%04x' for stream number %d\n",
412  (unsigned int) tmp, stream_id);
413 
414  GET_V(stc->time_base_id, tmp < nut->time_base_count);
415  GET_V(stc->msb_pts_shift, tmp < 16);
417  GET_V(stc->decode_delay, tmp < 1000); // sanity limit, raise this if Moore's law is true
418  st->codec->has_b_frames = stc->decode_delay;
419  ffio_read_varlen(bc); // stream flags
420 
421  GET_V(st->codec->extradata_size, tmp < (1 << 30));
422  if (st->codec->extradata_size) {
423  if (ff_get_extradata(st->codec, bc, st->codec->extradata_size) < 0)
424  return AVERROR(ENOMEM);
425  }
426 
427  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
428  GET_V(st->codec->width, tmp > 0);
429  GET_V(st->codec->height, tmp > 0);
432  if ((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)) {
433  av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n",
435  return AVERROR_INVALIDDATA;
436  }
437  ffio_read_varlen(bc); /* csp type */
438  } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
439  GET_V(st->codec->sample_rate, tmp > 0);
440  ffio_read_varlen(bc); // samplerate_den
441  GET_V(st->codec->channels, tmp > 0);
442  }
443  if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
444  av_log(s, AV_LOG_ERROR,
445  "stream header %d checksum mismatch\n", stream_id);
446  return AVERROR_INVALIDDATA;
447  }
448  stc->time_base = &nut->time_base[stc->time_base_id];
449  avpriv_set_pts_info(s->streams[stream_id], 63, stc->time_base->num,
450  stc->time_base->den);
451  return 0;
452 }
453 
455  int stream_id)
456 {
457  int flag = 0, i;
458 
459  for (i = 0; ff_nut_dispositions[i].flag; ++i)
460  if (!strcmp(ff_nut_dispositions[i].str, value))
461  flag = ff_nut_dispositions[i].flag;
462  if (!flag)
463  av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
464  for (i = 0; i < avf->nb_streams; ++i)
465  if (stream_id == i || stream_id == -1)
466  avf->streams[i]->disposition |= flag;
467 }
468 
470 {
471  AVFormatContext *s = nut->avf;
472  AVIOContext *bc = s->pb;
473  uint64_t tmp, chapter_start, chapter_len;
474  unsigned int stream_id_plus1, count;
475  int chapter_id, i;
476  int64_t value, end;
477  char name[256], str_value[1024], type_str[256];
478  const char *type;
479  AVChapter *chapter = NULL;
480  AVStream *st = NULL;
481  AVDictionary **metadata = NULL;
482 
483  end = get_packetheader(nut, bc, 1, INFO_STARTCODE);
484  end += avio_tell(bc);
485 
486  GET_V(stream_id_plus1, tmp <= s->nb_streams);
487  chapter_id = get_s(bc);
488  chapter_start = ffio_read_varlen(bc);
489  chapter_len = ffio_read_varlen(bc);
490  count = ffio_read_varlen(bc);
491 
492  if (chapter_id && !stream_id_plus1) {
493  int64_t start = chapter_start / nut->time_base_count;
494  chapter = avpriv_new_chapter(s, chapter_id,
495  nut->time_base[chapter_start %
496  nut->time_base_count],
497  start, start + chapter_len, NULL);
498  metadata = &chapter->metadata;
499  } else if (stream_id_plus1) {
500  st = s->streams[stream_id_plus1 - 1];
501  metadata = &st->metadata;
502  } else
503  metadata = &s->metadata;
504 
505  for (i = 0; i < count; i++) {
506  get_str(bc, name, sizeof(name));
507  value = get_s(bc);
508  if (value == -1) {
509  type = "UTF-8";
510  get_str(bc, str_value, sizeof(str_value));
511  } else if (value == -2) {
512  get_str(bc, type_str, sizeof(type_str));
513  type = type_str;
514  get_str(bc, str_value, sizeof(str_value));
515  } else if (value == -3) {
516  type = "s";
517  value = get_s(bc);
518  } else if (value == -4) {
519  type = "t";
520  value = ffio_read_varlen(bc);
521  } else if (value < -4) {
522  type = "r";
523  get_s(bc);
524  } else {
525  type = "v";
526  }
527 
528  if (stream_id_plus1 > s->nb_streams) {
529  av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
530  continue;
531  }
532 
533  if (!strcmp(type, "UTF-8")) {
534  if (chapter_id == 0 && !strcmp(name, "Disposition")) {
535  set_disposition_bits(s, str_value, stream_id_plus1 - 1);
536  continue;
537  }
538 
539  if (stream_id_plus1 && !strcmp(name, "r_frame_rate")) {
540  sscanf(str_value, "%d/%d", &st->r_frame_rate.num, &st->r_frame_rate.den);
541  if (st->r_frame_rate.num >= 1000LL*st->r_frame_rate.den)
542  st->r_frame_rate.num = st->r_frame_rate.den = 0;
543  continue;
544  }
545 
546  if (metadata && av_strcasecmp(name, "Uses") &&
547  av_strcasecmp(name, "Depends") && av_strcasecmp(name, "Replaces"))
548  av_dict_set(metadata, name, str_value, 0);
549  }
550  }
551 
552  if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
553  av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
554  return AVERROR_INVALIDDATA;
555  }
556  return 0;
557 }
558 
559 static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr)
560 {
561  AVFormatContext *s = nut->avf;
562  AVIOContext *bc = s->pb;
563  int64_t end;
564  uint64_t tmp;
565  int ret;
566 
567  nut->last_syncpoint_pos = avio_tell(bc) - 8;
568 
569  end = get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
570  end += avio_tell(bc);
571 
572  tmp = ffio_read_varlen(bc);
573  *back_ptr = nut->last_syncpoint_pos - 16 * ffio_read_varlen(bc);
574  if (*back_ptr < 0)
575  return AVERROR_INVALIDDATA;
576 
577  ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count],
578  tmp / nut->time_base_count);
579 
580  if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
581  av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
582  return AVERROR_INVALIDDATA;
583  }
584 
585  *ts = tmp / nut->time_base_count *
586  av_q2d(nut->time_base[tmp % nut->time_base_count]) * AV_TIME_BASE;
587 
588  if ((ret = ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts)) < 0)
589  return ret;
590 
591  return 0;
592 }
593 
594 //FIXME calculate exactly, this is just a good approximation.
595 static int64_t find_duration(NUTContext *nut, int64_t filesize)
596 {
597  AVFormatContext *s = nut->avf;
598  int64_t duration = 0;
599 
600  ff_find_last_ts(s, -1, &duration, NULL, nut_read_timestamp);
601 
602  if(duration > 0)
604  return duration;
605 }
606 
608 {
609  AVFormatContext *s = nut->avf;
610  AVIOContext *bc = s->pb;
611  uint64_t tmp, end;
612  int i, j, syncpoint_count;
613  int64_t filesize = avio_size(bc);
614  int64_t *syncpoints;
615  uint64_t max_pts;
616  int8_t *has_keyframe;
617  int ret = AVERROR_INVALIDDATA;
618 
619  if(filesize <= 0)
620  return -1;
621 
622  avio_seek(bc, filesize - 12, SEEK_SET);
623  avio_seek(bc, filesize - avio_rb64(bc), SEEK_SET);
624  if (avio_rb64(bc) != INDEX_STARTCODE) {
625  av_log(s, AV_LOG_ERROR, "no index at the end\n");
626 
627  if(s->duration<=0)
628  s->duration = find_duration(nut, filesize);
629  return ret;
630  }
631 
632  end = get_packetheader(nut, bc, 1, INDEX_STARTCODE);
633  end += avio_tell(bc);
634 
635  max_pts = ffio_read_varlen(bc);
636  s->duration = av_rescale_q(max_pts / nut->time_base_count,
637  nut->time_base[max_pts % nut->time_base_count],
640 
641  GET_V(syncpoint_count, tmp < INT_MAX / 8 && tmp > 0);
642  syncpoints = av_malloc_array(syncpoint_count, sizeof(int64_t));
643  has_keyframe = av_malloc_array(syncpoint_count + 1, sizeof(int8_t));
644  if (!syncpoints || !has_keyframe) {
645  ret = AVERROR(ENOMEM);
646  goto fail;
647  }
648  for (i = 0; i < syncpoint_count; i++) {
649  syncpoints[i] = ffio_read_varlen(bc);
650  if (syncpoints[i] <= 0)
651  goto fail;
652  if (i)
653  syncpoints[i] += syncpoints[i - 1];
654  }
655 
656  for (i = 0; i < s->nb_streams; i++) {
657  int64_t last_pts = -1;
658  for (j = 0; j < syncpoint_count;) {
659  uint64_t x = ffio_read_varlen(bc);
660  int type = x & 1;
661  int n = j;
662  x >>= 1;
663  if (type) {
664  int flag = x & 1;
665  x >>= 1;
666  if (n + x >= syncpoint_count + 1) {
667  av_log(s, AV_LOG_ERROR, "index overflow A %d + %"PRIu64" >= %d\n", n, x, syncpoint_count + 1);
668  goto fail;
669  }
670  while (x--)
671  has_keyframe[n++] = flag;
672  has_keyframe[n++] = !flag;
673  } else {
674  while (x != 1) {
675  if (n >= syncpoint_count + 1) {
676  av_log(s, AV_LOG_ERROR, "index overflow B\n");
677  goto fail;
678  }
679  has_keyframe[n++] = x & 1;
680  x >>= 1;
681  }
682  }
683  if (has_keyframe[0]) {
684  av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
685  goto fail;
686  }
687  av_assert0(n <= syncpoint_count + 1);
688  for (; j < n && j < syncpoint_count; j++) {
689  if (has_keyframe[j]) {
690  uint64_t B, A = ffio_read_varlen(bc);
691  if (!A) {
692  A = ffio_read_varlen(bc);
693  B = ffio_read_varlen(bc);
694  // eor_pts[j][i] = last_pts + A + B
695  } else
696  B = 0;
697  av_add_index_entry(s->streams[i], 16 * syncpoints[j - 1],
698  last_pts + A, 0, 0, AVINDEX_KEYFRAME);
699  last_pts += A + B;
700  }
701  }
702  }
703  }
704 
705  if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
706  av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
707  goto fail;
708  }
709  ret = 0;
710 
711 fail:
712  av_free(syncpoints);
713  av_free(has_keyframe);
714  return ret;
715 }
716 
718 {
719  NUTContext *nut = s->priv_data;
720  AVIOContext *bc = s->pb;
721  int64_t pos;
722  int initialized_stream_count;
723 
724  nut->avf = s;
725 
726  /* main header */
727  pos = 0;
728  do {
729  pos = find_startcode(bc, MAIN_STARTCODE, pos) + 1;
730  if (pos < 0 + 1) {
731  av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
732  return AVERROR_INVALIDDATA;
733  }
734  } while (decode_main_header(nut) < 0);
735 
736  /* stream headers */
737  pos = 0;
738  for (initialized_stream_count = 0; initialized_stream_count < s->nb_streams;) {
739  pos = find_startcode(bc, STREAM_STARTCODE, pos) + 1;
740  if (pos < 0 + 1) {
741  av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
742  return AVERROR_INVALIDDATA;
743  }
744  if (decode_stream_header(nut) >= 0)
745  initialized_stream_count++;
746  }
747 
748  /* info headers */
749  pos = 0;
750  for (;;) {
751  uint64_t startcode = find_any_startcode(bc, pos);
752  pos = avio_tell(bc);
753 
754  if (startcode == 0) {
755  av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
756  return AVERROR_INVALIDDATA;
757  } else if (startcode == SYNCPOINT_STARTCODE) {
758  nut->next_startcode = startcode;
759  break;
760  } else if (startcode != INFO_STARTCODE) {
761  continue;
762  }
763 
764  decode_info_header(nut);
765  }
766 
767  s->data_offset = pos - 8;
768 
769  if (bc->seekable) {
770  int64_t orig_pos = avio_tell(bc);
772  avio_seek(bc, orig_pos, SEEK_SET);
773  }
775 
777 
778  return 0;
779 }
780 
781 static int read_sm_data(AVFormatContext *s, AVIOContext *bc, AVPacket *pkt, int is_meta, int64_t maxpos)
782 {
783  int count = ffio_read_varlen(bc);
784  int skip_start = 0;
785  int skip_end = 0;
786  int channels = 0;
787  int64_t channel_layout = 0;
788  int sample_rate = 0;
789  int width = 0;
790  int height = 0;
791  int i;
792 
793  for (i=0; i<count; i++) {
794  uint8_t name[256], str_value[256], type_str[256];
795  int value;
796  if (avio_tell(bc) >= maxpos)
797  return AVERROR_INVALIDDATA;
798  get_str(bc, name, sizeof(name));
799  value = get_s(bc);
800 
801  if (value == -1) {
802  get_str(bc, str_value, sizeof(str_value));
803  av_log(s, AV_LOG_WARNING, "Unknown string %s / %s\n", name, str_value);
804  } else if (value == -2) {
805  uint8_t *dst = NULL;
806  int64_t v64, value_len;
807 
808  get_str(bc, type_str, sizeof(type_str));
809  value_len = ffio_read_varlen(bc);
810  if (avio_tell(bc) + value_len >= maxpos)
811  return AVERROR_INVALIDDATA;
812  if (!strcmp(name, "Palette")) {
813  dst = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, value_len);
814  } else if (!strcmp(name, "Extradata")) {
815  dst = av_packet_new_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA, value_len);
816  } else if (sscanf(name, "CodecSpecificSide%"SCNd64"", &v64) == 1) {
818  if(!dst)
819  return AVERROR(ENOMEM);
820  AV_WB64(dst, v64);
821  dst += 8;
822  } else if (!strcmp(name, "ChannelLayout") && value_len == 8) {
823  channel_layout = avio_rl64(bc);
824  continue;
825  } else {
826  av_log(s, AV_LOG_WARNING, "Unknown data %s / %s\n", name, type_str);
827  avio_skip(bc, value_len);
828  continue;
829  }
830  if(!dst)
831  return AVERROR(ENOMEM);
832  avio_read(bc, dst, value_len);
833  } else if (value == -3) {
834  value = get_s(bc);
835  } else if (value == -4) {
836  value = ffio_read_varlen(bc);
837  } else if (value < -4) {
838  get_s(bc);
839  } else {
840  if (!strcmp(name, "SkipStart")) {
841  skip_start = value;
842  } else if (!strcmp(name, "SkipEnd")) {
843  skip_end = value;
844  } else if (!strcmp(name, "Channels")) {
845  channels = value;
846  } else if (!strcmp(name, "SampleRate")) {
847  sample_rate = value;
848  } else if (!strcmp(name, "Width")) {
849  width = value;
850  } else if (!strcmp(name, "Height")) {
851  height = value;
852  } else {
853  av_log(s, AV_LOG_WARNING, "Unknown integer %s\n", name);
854  }
855  }
856  }
857 
858  if (channels || channel_layout || sample_rate || width || height) {
860  if (!dst)
861  return AVERROR(ENOMEM);
862  bytestream_put_le32(&dst,
864  AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT*(!!channel_layout) +
865  AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE*(!!sample_rate) +
866  AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS*(!!(width|height))
867  );
868  if (channels)
869  bytestream_put_le32(&dst, channels);
870  if (channel_layout)
871  bytestream_put_le64(&dst, channel_layout);
872  if (sample_rate)
873  bytestream_put_le32(&dst, sample_rate);
874  if (width || height){
875  bytestream_put_le32(&dst, width);
876  bytestream_put_le32(&dst, height);
877  }
878  }
879 
880  if (skip_start || skip_end) {
882  if (!dst)
883  return AVERROR(ENOMEM);
884  AV_WL32(dst, skip_start);
885  AV_WL32(dst+4, skip_end);
886  }
887 
888  return 0;
889 }
890 
891 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id,
892  uint8_t *header_idx, int frame_code)
893 {
894  AVFormatContext *s = nut->avf;
895  AVIOContext *bc = s->pb;
896  StreamContext *stc;
897  int size, flags, size_mul, pts_delta, i, reserved_count;
898  uint64_t tmp;
899 
900  if (avio_tell(bc) > nut->last_syncpoint_pos + nut->max_distance) {
901  av_log(s, AV_LOG_ERROR,
902  "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n",
903  avio_tell(bc), nut->last_syncpoint_pos, nut->max_distance);
904  return AVERROR_INVALIDDATA;
905  }
906 
907  flags = nut->frame_code[frame_code].flags;
908  size_mul = nut->frame_code[frame_code].size_mul;
909  size = nut->frame_code[frame_code].size_lsb;
910  *stream_id = nut->frame_code[frame_code].stream_id;
911  pts_delta = nut->frame_code[frame_code].pts_delta;
912  reserved_count = nut->frame_code[frame_code].reserved_count;
913  *header_idx = nut->frame_code[frame_code].header_idx;
914 
915  if (flags & FLAG_INVALID)
916  return AVERROR_INVALIDDATA;
917  if (flags & FLAG_CODED)
918  flags ^= ffio_read_varlen(bc);
919  if (flags & FLAG_STREAM_ID) {
920  GET_V(*stream_id, tmp < s->nb_streams);
921  }
922  stc = &nut->stream[*stream_id];
923  if (flags & FLAG_CODED_PTS) {
924  int coded_pts = ffio_read_varlen(bc);
925  // FIXME check last_pts validity?
926  if (coded_pts < (1 << stc->msb_pts_shift)) {
927  *pts = ff_lsb2full(stc, coded_pts);
928  } else
929  *pts = coded_pts - (1LL << stc->msb_pts_shift);
930  } else
931  *pts = stc->last_pts + pts_delta;
932  if (flags & FLAG_SIZE_MSB)
933  size += size_mul * ffio_read_varlen(bc);
934  if (flags & FLAG_MATCH_TIME)
935  get_s(bc);
936  if (flags & FLAG_HEADER_IDX)
937  *header_idx = ffio_read_varlen(bc);
938  if (flags & FLAG_RESERVED)
939  reserved_count = ffio_read_varlen(bc);
940  for (i = 0; i < reserved_count; i++)
941  ffio_read_varlen(bc);
942 
943  if (*header_idx >= (unsigned)nut->header_count) {
944  av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
945  return AVERROR_INVALIDDATA;
946  }
947  if (size > 4096)
948  *header_idx = 0;
949  size -= nut->header_len[*header_idx];
950 
951  if (flags & FLAG_CHECKSUM) {
952  avio_rb32(bc); // FIXME check this
953  } else if (size > 2 * nut->max_distance || FFABS(stc->last_pts - *pts) >
954  stc->max_pts_distance) {
955  av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
956  return AVERROR_INVALIDDATA;
957  }
958 
959  stc->last_pts = *pts;
960  stc->last_flags = flags;
961 
962  return size;
963 }
964 
965 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code)
966 {
967  AVFormatContext *s = nut->avf;
968  AVIOContext *bc = s->pb;
969  int size, stream_id, discard;
970  int64_t pts, last_IP_pts;
971  StreamContext *stc;
972  uint8_t header_idx;
973  int ret;
974 
975  size = decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
976  if (size < 0)
977  return size;
978 
979  stc = &nut->stream[stream_id];
980 
981  if (stc->last_flags & FLAG_KEY)
982  stc->skip_until_key_frame = 0;
983 
984  discard = s->streams[stream_id]->discard;
985  last_IP_pts = s->streams[stream_id]->last_IP_pts;
986  if ((discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) ||
987  (discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE &&
988  last_IP_pts > pts) ||
989  discard >= AVDISCARD_ALL ||
990  stc->skip_until_key_frame) {
991  avio_skip(bc, size);
992  return 1;
993  }
994 
995  if (av_new_packet(pkt, size + nut->header_len[header_idx]) < 0)
996  return AVERROR(ENOMEM);
997  memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
998  pkt->pos = avio_tell(bc); // FIXME
999  if (stc->last_flags & FLAG_SM_DATA) {
1000  int sm_size;
1001  if (read_sm_data(s, bc, pkt, 0, pkt->pos + size) < 0)
1002  return AVERROR_INVALIDDATA;
1003  if (read_sm_data(s, bc, pkt, 1, pkt->pos + size) < 0)
1004  return AVERROR_INVALIDDATA;
1005  sm_size = avio_tell(bc) - pkt->pos;
1006  size -= sm_size;
1007  pkt->size -= sm_size;
1008  }
1009 
1010  ret = avio_read(bc, pkt->data + nut->header_len[header_idx], size);
1011  if (ret != size) {
1012  if (ret < 0)
1013  return ret;
1014  }
1015  av_shrink_packet(pkt, nut->header_len[header_idx] + ret);
1016 
1017  pkt->stream_index = stream_id;
1018  if (stc->last_flags & FLAG_KEY)
1019  pkt->flags |= AV_PKT_FLAG_KEY;
1020  pkt->pts = pts;
1021 
1022  return 0;
1023 }
1024 
1026 {
1027  NUTContext *nut = s->priv_data;
1028  AVIOContext *bc = s->pb;
1029  int i, frame_code = 0, ret, skip;
1030  int64_t ts, back_ptr;
1031 
1032  for (;;) {
1033  int64_t pos = avio_tell(bc);
1034  uint64_t tmp = nut->next_startcode;
1035  nut->next_startcode = 0;
1036 
1037  if (tmp) {
1038  pos -= 8;
1039  } else {
1040  frame_code = avio_r8(bc);
1041  if (url_feof(bc))
1042  return AVERROR_EOF;
1043  if (frame_code == 'N') {
1044  tmp = frame_code;
1045  for (i = 1; i < 8; i++)
1046  tmp = (tmp << 8) + avio_r8(bc);
1047  }
1048  }
1049  switch (tmp) {
1050  case MAIN_STARTCODE:
1051  case STREAM_STARTCODE:
1052  case INDEX_STARTCODE:
1053  skip = get_packetheader(nut, bc, 0, tmp);
1054  avio_skip(bc, skip);
1055  break;
1056  case INFO_STARTCODE:
1057  if (decode_info_header(nut) < 0)
1058  goto resync;
1059  break;
1060  case SYNCPOINT_STARTCODE:
1061  if (decode_syncpoint(nut, &ts, &back_ptr) < 0)
1062  goto resync;
1063  frame_code = avio_r8(bc);
1064  case 0:
1065  ret = decode_frame(nut, pkt, frame_code);
1066  if (ret == 0)
1067  return 0;
1068  else if (ret == 1) // OK but discard packet
1069  break;
1070  default:
1071 resync:
1072  av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
1073  tmp = find_any_startcode(bc, nut->last_syncpoint_pos + 1);
1074  if (tmp == 0)
1075  return AVERROR_INVALIDDATA;
1076  av_log(s, AV_LOG_DEBUG, "sync\n");
1077  nut->next_startcode = tmp;
1078  }
1079  }
1080 }
1081 
1082 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
1083  int64_t *pos_arg, int64_t pos_limit)
1084 {
1085  NUTContext *nut = s->priv_data;
1086  AVIOContext *bc = s->pb;
1087  int64_t pos, pts, back_ptr;
1088  av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n",
1089  stream_index, *pos_arg, pos_limit);
1090 
1091  pos = *pos_arg;
1092  do {
1093  pos = find_startcode(bc, SYNCPOINT_STARTCODE, pos) + 1;
1094  if (pos < 1) {
1095  av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
1096  return AV_NOPTS_VALUE;
1097  }
1098  } while (decode_syncpoint(nut, &pts, &back_ptr) < 0);
1099  *pos_arg = pos - 1;
1100  av_assert0(nut->last_syncpoint_pos == *pos_arg);
1101 
1102  av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts, back_ptr);
1103  if (stream_index == -2)
1104  return back_ptr;
1105  av_assert0(stream_index == -1);
1106  return pts;
1107 }
1108 
1109 static int read_seek(AVFormatContext *s, int stream_index,
1110  int64_t pts, int flags)
1111 {
1112  NUTContext *nut = s->priv_data;
1113  AVStream *st = s->streams[stream_index];
1114  Syncpoint dummy = { .ts = pts * av_q2d(st->time_base) * AV_TIME_BASE };
1115  Syncpoint nopts_sp = { .ts = AV_NOPTS_VALUE, .back_ptr = AV_NOPTS_VALUE };
1116  Syncpoint *sp, *next_node[2] = { &nopts_sp, &nopts_sp };
1117  int64_t pos, pos2, ts;
1118  int i;
1119 
1120  if (st->index_entries) {
1121  int index = av_index_search_timestamp(st, pts, flags);
1122  if (index < 0)
1123  index = av_index_search_timestamp(st, pts, flags ^ AVSEEK_FLAG_BACKWARD);
1124  if (index < 0)
1125  return -1;
1126 
1127  pos2 = st->index_entries[index].pos;
1128  ts = st->index_entries[index].timestamp;
1129  } else {
1130  av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
1131  (void **) next_node);
1132  av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n",
1133  next_node[0]->pos, next_node[1]->pos, next_node[0]->ts,
1134  next_node[1]->ts);
1135  pos = ff_gen_search(s, -1, dummy.ts, next_node[0]->pos,
1136  next_node[1]->pos, next_node[1]->pos,
1137  next_node[0]->ts, next_node[1]->ts,
1139 
1140  if (!(flags & AVSEEK_FLAG_BACKWARD)) {
1141  dummy.pos = pos + 16;
1142  next_node[1] = &nopts_sp;
1143  av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
1144  (void **) next_node);
1145  pos2 = ff_gen_search(s, -2, dummy.pos, next_node[0]->pos,
1146  next_node[1]->pos, next_node[1]->pos,
1147  next_node[0]->back_ptr, next_node[1]->back_ptr,
1148  flags, &ts, nut_read_timestamp);
1149  if (pos2 >= 0)
1150  pos = pos2;
1151  // FIXME dir but I think it does not matter
1152  }
1153  dummy.pos = pos;
1154  sp = av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
1155  NULL);
1156 
1157  av_assert0(sp);
1158  pos2 = sp->back_ptr - 15;
1159  }
1160  av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
1161  pos = find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
1162  avio_seek(s->pb, pos, SEEK_SET);
1163  av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
1164  if (pos2 > pos || pos2 + 15 < pos)
1165  av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
1166  for (i = 0; i < s->nb_streams; i++)
1167  nut->stream[i].skip_until_key_frame = 1;
1168 
1169  return 0;
1170 }
1171 
1173 {
1174  NUTContext *nut = s->priv_data;
1175  int i;
1176 
1177  av_freep(&nut->time_base);
1178  av_freep(&nut->stream);
1179  ff_nut_free_sp(nut);
1180  for (i = 1; i < nut->header_count; i++)
1181  av_freep(&nut->header[i]);
1182 
1183  return 0;
1184 }
1185 
1187  .name = "nut",
1188  .long_name = NULL_IF_CONFIG_SMALL("NUT"),
1189  .flags = AVFMT_SEEK_TO_PTS,
1190  .priv_data_size = sizeof(NUTContext),
1191  .read_probe = nut_probe,
1195  .read_seek = read_seek,
1196  .extensions = "nut",
1197  .codec_tag = ff_nut_codec_tags,
1198 };