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hls.c
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1 /*
2  * Apple HTTP Live Streaming demuxer
3  * Copyright (c) 2010 Martin Storsjo
4  * Copyright (c) 2013 Anssi Hannula
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 /**
24  * @file
25  * Apple HTTP Live Streaming demuxer
26  * http://tools.ietf.org/html/draft-pantos-http-live-streaming
27  */
28 
29 #include "libavutil/avstring.h"
30 #include "libavutil/avassert.h"
31 #include "libavutil/intreadwrite.h"
32 #include "libavutil/mathematics.h"
33 #include "libavutil/opt.h"
34 #include "libavutil/dict.h"
35 #include "libavutil/time.h"
36 #include "avformat.h"
37 #include "internal.h"
38 #include "avio_internal.h"
39 #include "url.h"
40 #include "id3v2.h"
41 
42 #define INITIAL_BUFFER_SIZE 32768
43 
44 #define MAX_FIELD_LEN 64
45 #define MAX_CHARACTERISTICS_LEN 512
46 
47 #define MPEG_TIME_BASE 90000
48 #define MPEG_TIME_BASE_Q (AVRational){1, MPEG_TIME_BASE}
49 
50 /*
51  * An apple http stream consists of a playlist with media segment files,
52  * played sequentially. There may be several playlists with the same
53  * video content, in different bandwidth variants, that are played in
54  * parallel (preferably only one bandwidth variant at a time). In this case,
55  * the user supplied the url to a main playlist that only lists the variant
56  * playlists.
57  *
58  * If the main playlist doesn't point at any variants, we still create
59  * one anonymous toplevel variant for this, to maintain the structure.
60  */
61 
62 enum KeyType {
66 };
67 
68 struct segment {
69  int64_t duration;
70  int64_t url_offset;
71  int64_t size;
72  char *url;
73  char *key;
75  uint8_t iv[16];
76 };
77 
78 struct rendition;
79 
84 };
85 
86 /*
87  * Each playlist has its own demuxer. If it currently is active,
88  * it has an open AVIOContext too, and potentially an AVPacket
89  * containing the next packet from this stream.
90  */
91 struct playlist {
97  int index;
101 
102  int finished;
107  struct segment **segments;
110  int64_t cur_seg_offset;
111  int64_t last_load_time;
112 
115 
116  /* ID3 timestamp handling (elementary audio streams have ID3 timestamps
117  * (and possibly other ID3 tags) in the beginning of each segment) */
118  int is_id3_timestamped; /* -1: not yet known */
119  int64_t id3_mpegts_timestamp; /* in mpegts tb */
120  int64_t id3_offset; /* in stream original tb */
121  uint8_t* id3_buf; /* temp buffer for id3 parsing */
122  unsigned int id3_buf_size;
123  AVDictionary *id3_initial; /* data from first id3 tag */
124  int id3_found; /* ID3 tag found at some point */
125  int id3_changed; /* ID3 tag data has changed at some point */
126  ID3v2ExtraMeta *id3_deferred_extra; /* stored here until subdemuxer is opened */
127 
128  int64_t seek_timestamp;
130  int seek_stream_index; /* into subdemuxer stream array */
131 
132  /* Renditions associated with this playlist, if any.
133  * Alternative rendition playlists have a single rendition associated
134  * with them, and variant main Media Playlists may have
135  * multiple (playlist-less) renditions associated with them. */
138 };
139 
140 /*
141  * Renditions are e.g. alternative subtitle or audio streams.
142  * The rendition may either be an external playlist or it may be
143  * contained in the main Media Playlist of the variant (in which case
144  * playlist is NULL).
145  */
146 struct rendition {
153 };
154 
155 struct variant {
157 
158  /* every variant contains at least the main Media Playlist in index 0 */
160  struct playlist **playlists;
161 
165 };
166 
167 typedef struct HLSContext {
168  AVClass *class;
170  struct variant **variants;
172  struct playlist **playlists;
175 
180  int64_t cur_timestamp;
182  char *user_agent; ///< holds HTTP user agent set as an AVOption to the HTTP protocol context
183  char *cookies; ///< holds HTTP cookie values set in either the initial response or as an AVOption to the HTTP protocol context
184  char *headers; ///< holds HTTP headers set as an AVOption to the HTTP protocol context
185 } HLSContext;
186 
187 static int read_chomp_line(AVIOContext *s, char *buf, int maxlen)
188 {
189  int len = ff_get_line(s, buf, maxlen);
190  while (len > 0 && av_isspace(buf[len - 1]))
191  buf[--len] = '\0';
192  return len;
193 }
194 
195 static void free_segment_list(struct playlist *pls)
196 {
197  int i;
198  for (i = 0; i < pls->n_segments; i++) {
199  av_freep(&pls->segments[i]->key);
200  av_freep(&pls->segments[i]->url);
201  av_freep(&pls->segments[i]);
202  }
203  av_freep(&pls->segments);
204  pls->n_segments = 0;
205 }
206 
208 {
209  int i;
210  for (i = 0; i < c->n_playlists; i++) {
211  struct playlist *pls = c->playlists[i];
212  free_segment_list(pls);
213  av_freep(&pls->renditions);
214  av_freep(&pls->id3_buf);
215  av_dict_free(&pls->id3_initial);
217  av_free_packet(&pls->pkt);
218  av_freep(&pls->pb.buffer);
219  if (pls->input)
220  ffurl_close(pls->input);
221  if (pls->ctx) {
222  pls->ctx->pb = NULL;
223  avformat_close_input(&pls->ctx);
224  }
225  av_free(pls);
226  }
227  av_freep(&c->playlists);
228  av_freep(&c->cookies);
229  av_freep(&c->user_agent);
230  c->n_playlists = 0;
231 }
232 
234 {
235  int i;
236  for (i = 0; i < c->n_variants; i++) {
237  struct variant *var = c->variants[i];
238  av_freep(&var->playlists);
239  av_free(var);
240  }
241  av_freep(&c->variants);
242  c->n_variants = 0;
243 }
244 
246 {
247  int i;
248  for (i = 0; i < c->n_renditions; i++)
249  av_freep(&c->renditions[i]);
250  av_freep(&c->renditions);
251  c->n_renditions = 0;
252 }
253 
254 /*
255  * Used to reset a statically allocated AVPacket to a clean slate,
256  * containing no data.
257  */
258 static void reset_packet(AVPacket *pkt)
259 {
260  av_init_packet(pkt);
261  pkt->data = NULL;
262 }
263 
264 static struct playlist *new_playlist(HLSContext *c, const char *url,
265  const char *base)
266 {
267  struct playlist *pls = av_mallocz(sizeof(struct playlist));
268  if (!pls)
269  return NULL;
270  reset_packet(&pls->pkt);
271  ff_make_absolute_url(pls->url, sizeof(pls->url), base, url);
273 
274  pls->is_id3_timestamped = -1;
276 
277  dynarray_add(&c->playlists, &c->n_playlists, pls);
278  return pls;
279 }
280 
281 struct variant_info {
282  char bandwidth[20];
283  /* variant group ids: */
287 };
288 
289 static struct variant *new_variant(HLSContext *c, struct variant_info *info,
290  const char *url, const char *base)
291 {
292  struct variant *var;
293  struct playlist *pls;
294 
295  pls = new_playlist(c, url, base);
296  if (!pls)
297  return NULL;
298 
299  var = av_mallocz(sizeof(struct variant));
300  if (!var)
301  return NULL;
302 
303  if (info) {
304  var->bandwidth = atoi(info->bandwidth);
305  strcpy(var->audio_group, info->audio);
306  strcpy(var->video_group, info->video);
307  strcpy(var->subtitles_group, info->subtitles);
308  }
309 
310  dynarray_add(&c->variants, &c->n_variants, var);
311  dynarray_add(&var->playlists, &var->n_playlists, pls);
312  return var;
313 }
314 
315 static void handle_variant_args(struct variant_info *info, const char *key,
316  int key_len, char **dest, int *dest_len)
317 {
318  if (!strncmp(key, "BANDWIDTH=", key_len)) {
319  *dest = info->bandwidth;
320  *dest_len = sizeof(info->bandwidth);
321  } else if (!strncmp(key, "AUDIO=", key_len)) {
322  *dest = info->audio;
323  *dest_len = sizeof(info->audio);
324  } else if (!strncmp(key, "VIDEO=", key_len)) {
325  *dest = info->video;
326  *dest_len = sizeof(info->video);
327  } else if (!strncmp(key, "SUBTITLES=", key_len)) {
328  *dest = info->subtitles;
329  *dest_len = sizeof(info->subtitles);
330  }
331 }
332 
333 struct key_info {
335  char method[11];
336  char iv[35];
337 };
338 
339 static void handle_key_args(struct key_info *info, const char *key,
340  int key_len, char **dest, int *dest_len)
341 {
342  if (!strncmp(key, "METHOD=", key_len)) {
343  *dest = info->method;
344  *dest_len = sizeof(info->method);
345  } else if (!strncmp(key, "URI=", key_len)) {
346  *dest = info->uri;
347  *dest_len = sizeof(info->uri);
348  } else if (!strncmp(key, "IV=", key_len)) {
349  *dest = info->iv;
350  *dest_len = sizeof(info->iv);
351  }
352 }
353 
355  char type[16];
361  char defaultr[4];
362  char forced[4];
364 };
365 
366 static struct rendition *new_rendition(HLSContext *c, struct rendition_info *info,
367  const char *url_base)
368 {
369  struct rendition *rend;
371  char *characteristic;
372  char *chr_ptr;
373  char *saveptr;
374 
375  if (!strcmp(info->type, "AUDIO"))
376  type = AVMEDIA_TYPE_AUDIO;
377  else if (!strcmp(info->type, "VIDEO"))
378  type = AVMEDIA_TYPE_VIDEO;
379  else if (!strcmp(info->type, "SUBTITLES"))
380  type = AVMEDIA_TYPE_SUBTITLE;
381  else if (!strcmp(info->type, "CLOSED-CAPTIONS"))
382  /* CLOSED-CAPTIONS is ignored since we do not support CEA-608 CC in
383  * AVC SEI RBSP anyway */
384  return NULL;
385 
386  if (type == AVMEDIA_TYPE_UNKNOWN)
387  return NULL;
388 
389  /* URI is mandatory for subtitles as per spec */
390  if (type == AVMEDIA_TYPE_SUBTITLE && !info->uri[0])
391  return NULL;
392 
393  /* TODO: handle subtitles (each segment has to parsed separately) */
394  if (type == AVMEDIA_TYPE_SUBTITLE)
395  return NULL;
396 
397  rend = av_mallocz(sizeof(struct rendition));
398  if (!rend)
399  return NULL;
400 
401  dynarray_add(&c->renditions, &c->n_renditions, rend);
402 
403  rend->type = type;
404  strcpy(rend->group_id, info->group_id);
405  strcpy(rend->language, info->language);
406  strcpy(rend->name, info->name);
407 
408  /* add the playlist if this is an external rendition */
409  if (info->uri[0]) {
410  rend->playlist = new_playlist(c, info->uri, url_base);
411  if (rend->playlist)
413  &rend->playlist->n_renditions, rend);
414  }
415 
416  if (info->assoc_language[0]) {
417  int langlen = strlen(rend->language);
418  if (langlen < sizeof(rend->language) - 3) {
419  rend->language[langlen] = ',';
420  strncpy(rend->language + langlen + 1, info->assoc_language,
421  sizeof(rend->language) - langlen - 2);
422  }
423  }
424 
425  if (!strcmp(info->defaultr, "YES"))
427  if (!strcmp(info->forced, "YES"))
429 
430  chr_ptr = info->characteristics;
431  while ((characteristic = av_strtok(chr_ptr, ",", &saveptr))) {
432  if (!strcmp(characteristic, "public.accessibility.describes-music-and-sound"))
434  else if (!strcmp(characteristic, "public.accessibility.describes-video"))
436 
437  chr_ptr = NULL;
438  }
439 
440  return rend;
441 }
442 
443 static void handle_rendition_args(struct rendition_info *info, const char *key,
444  int key_len, char **dest, int *dest_len)
445 {
446  if (!strncmp(key, "TYPE=", key_len)) {
447  *dest = info->type;
448  *dest_len = sizeof(info->type);
449  } else if (!strncmp(key, "URI=", key_len)) {
450  *dest = info->uri;
451  *dest_len = sizeof(info->uri);
452  } else if (!strncmp(key, "GROUP-ID=", key_len)) {
453  *dest = info->group_id;
454  *dest_len = sizeof(info->group_id);
455  } else if (!strncmp(key, "LANGUAGE=", key_len)) {
456  *dest = info->language;
457  *dest_len = sizeof(info->language);
458  } else if (!strncmp(key, "ASSOC-LANGUAGE=", key_len)) {
459  *dest = info->assoc_language;
460  *dest_len = sizeof(info->assoc_language);
461  } else if (!strncmp(key, "NAME=", key_len)) {
462  *dest = info->name;
463  *dest_len = sizeof(info->name);
464  } else if (!strncmp(key, "DEFAULT=", key_len)) {
465  *dest = info->defaultr;
466  *dest_len = sizeof(info->defaultr);
467  } else if (!strncmp(key, "FORCED=", key_len)) {
468  *dest = info->forced;
469  *dest_len = sizeof(info->forced);
470  } else if (!strncmp(key, "CHARACTERISTICS=", key_len)) {
471  *dest = info->characteristics;
472  *dest_len = sizeof(info->characteristics);
473  }
474  /*
475  * ignored:
476  * - AUTOSELECT: client may autoselect based on e.g. system language
477  * - INSTREAM-ID: EIA-608 closed caption number ("CC1".."CC4")
478  */
479 }
480 
481 /* used by parse_playlist to allocate a new variant+playlist when the
482  * playlist is detected to be a Media Playlist (not Master Playlist)
483  * and we have no parent Master Playlist (parsing of which would have
484  * allocated the variant and playlist already) */
485 static int ensure_playlist(HLSContext *c, struct playlist **pls, const char *url)
486 {
487  if (*pls)
488  return 0;
489  if (!new_variant(c, NULL, url, NULL))
490  return AVERROR(ENOMEM);
491  *pls = c->playlists[c->n_playlists - 1];
492  return 0;
493 }
494 
495 /* pls = NULL => Master Playlist or parentless Media Playlist
496  * pls = !NULL => parented Media Playlist, playlist+variant allocated */
497 static int parse_playlist(HLSContext *c, const char *url,
498  struct playlist *pls, AVIOContext *in)
499 {
500  int ret = 0, is_segment = 0, is_variant = 0;
501  int64_t duration = 0;
502  enum KeyType key_type = KEY_NONE;
503  uint8_t iv[16] = "";
504  int has_iv = 0;
505  char key[MAX_URL_SIZE] = "";
506  char line[MAX_URL_SIZE];
507  const char *ptr;
508  int close_in = 0;
509  int64_t seg_offset = 0;
510  int64_t seg_size = -1;
511  uint8_t *new_url = NULL;
512  struct variant_info variant_info;
513  char tmp_str[MAX_URL_SIZE];
514 
515  if (!in) {
516  AVDictionary *opts = NULL;
517  close_in = 1;
518  /* Some HLS servers don't like being sent the range header */
519  av_dict_set(&opts, "seekable", "0", 0);
520 
521  // broker prior HTTP options that should be consistent across requests
522  av_dict_set(&opts, "user-agent", c->user_agent, 0);
523  av_dict_set(&opts, "cookies", c->cookies, 0);
524  av_dict_set(&opts, "headers", c->headers, 0);
525 
526  ret = avio_open2(&in, url, AVIO_FLAG_READ,
527  c->interrupt_callback, &opts);
528  av_dict_free(&opts);
529  if (ret < 0)
530  return ret;
531  }
532 
533  if (av_opt_get(in, "location", AV_OPT_SEARCH_CHILDREN, &new_url) >= 0)
534  url = new_url;
535 
536  read_chomp_line(in, line, sizeof(line));
537  if (strcmp(line, "#EXTM3U")) {
538  ret = AVERROR_INVALIDDATA;
539  goto fail;
540  }
541 
542  if (pls) {
543  free_segment_list(pls);
544  pls->finished = 0;
545  pls->type = PLS_TYPE_UNSPECIFIED;
546  }
547  while (!avio_feof(in)) {
548  read_chomp_line(in, line, sizeof(line));
549  if (av_strstart(line, "#EXT-X-STREAM-INF:", &ptr)) {
550  is_variant = 1;
551  memset(&variant_info, 0, sizeof(variant_info));
553  &variant_info);
554  } else if (av_strstart(line, "#EXT-X-KEY:", &ptr)) {
555  struct key_info info = {{0}};
557  &info);
558  key_type = KEY_NONE;
559  has_iv = 0;
560  if (!strcmp(info.method, "AES-128"))
561  key_type = KEY_AES_128;
562  if (!strcmp(info.method, "SAMPLE-AES"))
563  key_type = KEY_SAMPLE_AES;
564  if (!strncmp(info.iv, "0x", 2) || !strncmp(info.iv, "0X", 2)) {
565  ff_hex_to_data(iv, info.iv + 2);
566  has_iv = 1;
567  }
568  av_strlcpy(key, info.uri, sizeof(key));
569  } else if (av_strstart(line, "#EXT-X-MEDIA:", &ptr)) {
570  struct rendition_info info = {{0}};
572  &info);
573  new_rendition(c, &info, url);
574  } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) {
575  ret = ensure_playlist(c, &pls, url);
576  if (ret < 0)
577  goto fail;
578  pls->target_duration = atoi(ptr) * AV_TIME_BASE;
579  } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) {
580  ret = ensure_playlist(c, &pls, url);
581  if (ret < 0)
582  goto fail;
583  pls->start_seq_no = atoi(ptr);
584  } else if (av_strstart(line, "#EXT-X-PLAYLIST-TYPE:", &ptr)) {
585  ret = ensure_playlist(c, &pls, url);
586  if (ret < 0)
587  goto fail;
588  if (!strcmp(ptr, "EVENT"))
589  pls->type = PLS_TYPE_EVENT;
590  else if (!strcmp(ptr, "VOD"))
591  pls->type = PLS_TYPE_VOD;
592  } else if (av_strstart(line, "#EXT-X-ENDLIST", &ptr)) {
593  if (pls)
594  pls->finished = 1;
595  } else if (av_strstart(line, "#EXTINF:", &ptr)) {
596  is_segment = 1;
597  duration = atof(ptr) * AV_TIME_BASE;
598  } else if (av_strstart(line, "#EXT-X-BYTERANGE:", &ptr)) {
599  seg_size = atoi(ptr);
600  ptr = strchr(ptr, '@');
601  if (ptr)
602  seg_offset = atoi(ptr+1);
603  } else if (av_strstart(line, "#", NULL)) {
604  continue;
605  } else if (line[0]) {
606  if (is_variant) {
607  if (!new_variant(c, &variant_info, line, url)) {
608  ret = AVERROR(ENOMEM);
609  goto fail;
610  }
611  is_variant = 0;
612  }
613  if (is_segment) {
614  struct segment *seg;
615  if (!pls) {
616  if (!new_variant(c, 0, url, NULL)) {
617  ret = AVERROR(ENOMEM);
618  goto fail;
619  }
620  pls = c->playlists[c->n_playlists - 1];
621  }
622  seg = av_malloc(sizeof(struct segment));
623  if (!seg) {
624  ret = AVERROR(ENOMEM);
625  goto fail;
626  }
627  seg->duration = duration;
628  seg->key_type = key_type;
629  if (has_iv) {
630  memcpy(seg->iv, iv, sizeof(iv));
631  } else {
632  int seq = pls->start_seq_no + pls->n_segments;
633  memset(seg->iv, 0, sizeof(seg->iv));
634  AV_WB32(seg->iv + 12, seq);
635  }
636 
637  if (key_type != KEY_NONE) {
638  ff_make_absolute_url(tmp_str, sizeof(tmp_str), url, key);
639  seg->key = av_strdup(tmp_str);
640  if (!seg->key) {
641  av_free(seg);
642  ret = AVERROR(ENOMEM);
643  goto fail;
644  }
645  } else {
646  seg->key = NULL;
647  }
648 
649  ff_make_absolute_url(tmp_str, sizeof(tmp_str), url, line);
650  seg->url = av_strdup(tmp_str);
651  if (!seg->url) {
652  av_free(seg->key);
653  av_free(seg);
654  ret = AVERROR(ENOMEM);
655  goto fail;
656  }
657 
658  dynarray_add(&pls->segments, &pls->n_segments, seg);
659  is_segment = 0;
660 
661  seg->size = seg_size;
662  if (seg_size >= 0) {
663  seg->url_offset = seg_offset;
664  seg_offset += seg_size;
665  seg_size = -1;
666  } else {
667  seg->url_offset = 0;
668  seg_offset = 0;
669  }
670  }
671  }
672  }
673  if (pls)
675 
676 fail:
677  av_free(new_url);
678  if (close_in)
679  avio_close(in);
680  return ret;
681 }
682 
686 };
687 
688 /* read from URLContext, limiting read to current segment */
689 static int read_from_url(struct playlist *pls, uint8_t *buf, int buf_size,
690  enum ReadFromURLMode mode)
691 {
692  int ret;
693  struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no];
694 
695  /* limit read if the segment was only a part of a file */
696  if (seg->size >= 0)
697  buf_size = FFMIN(buf_size, seg->size - pls->cur_seg_offset);
698 
699  if (mode == READ_COMPLETE)
700  ret = ffurl_read_complete(pls->input, buf, buf_size);
701  else
702  ret = ffurl_read(pls->input, buf, buf_size);
703 
704  if (ret > 0)
705  pls->cur_seg_offset += ret;
706 
707  return ret;
708 }
709 
710 /* Parse the raw ID3 data and pass contents to caller */
712  AVDictionary **metadata, int64_t *dts,
713  ID3v2ExtraMetaAPIC **apic, ID3v2ExtraMeta **extra_meta)
714 {
715  static const char id3_priv_owner_ts[] = "com.apple.streaming.transportStreamTimestamp";
716  ID3v2ExtraMeta *meta;
717 
718  ff_id3v2_read_dict(pb, metadata, ID3v2_DEFAULT_MAGIC, extra_meta);
719  for (meta = *extra_meta; meta; meta = meta->next) {
720  if (!strcmp(meta->tag, "PRIV")) {
721  ID3v2ExtraMetaPRIV *priv = meta->data;
722  if (priv->datasize == 8 && !strcmp(priv->owner, id3_priv_owner_ts)) {
723  /* 33-bit MPEG timestamp */
724  int64_t ts = AV_RB64(priv->data);
725  av_log(s, AV_LOG_DEBUG, "HLS ID3 audio timestamp %"PRId64"\n", ts);
726  if ((ts & ~((1ULL << 33) - 1)) == 0)
727  *dts = ts;
728  else
729  av_log(s, AV_LOG_ERROR, "Invalid HLS ID3 audio timestamp %"PRId64"\n", ts);
730  }
731  } else if (!strcmp(meta->tag, "APIC") && apic)
732  *apic = meta->data;
733  }
734 }
735 
736 /* Check if the ID3 metadata contents have changed */
737 static int id3_has_changed_values(struct playlist *pls, AVDictionary *metadata,
738  ID3v2ExtraMetaAPIC *apic)
739 {
740  AVDictionaryEntry *entry = NULL;
741  AVDictionaryEntry *oldentry;
742  /* check that no keys have changed values */
743  while ((entry = av_dict_get(metadata, "", entry, AV_DICT_IGNORE_SUFFIX))) {
744  oldentry = av_dict_get(pls->id3_initial, entry->key, NULL, AV_DICT_MATCH_CASE);
745  if (!oldentry || strcmp(oldentry->value, entry->value) != 0)
746  return 1;
747  }
748 
749  /* check if apic appeared */
750  if (apic && (pls->ctx->nb_streams != 2 || !pls->ctx->streams[1]->attached_pic.data))
751  return 1;
752 
753  if (apic) {
754  int size = pls->ctx->streams[1]->attached_pic.size;
755  if (size != apic->buf->size - FF_INPUT_BUFFER_PADDING_SIZE)
756  return 1;
757 
758  if (memcmp(apic->buf->data, pls->ctx->streams[1]->attached_pic.data, size) != 0)
759  return 1;
760  }
761 
762  return 0;
763 }
764 
765 /* Parse ID3 data and handle the found data */
766 static void handle_id3(AVIOContext *pb, struct playlist *pls)
767 {
768  AVDictionary *metadata = NULL;
769  ID3v2ExtraMetaAPIC *apic = NULL;
770  ID3v2ExtraMeta *extra_meta = NULL;
771  int64_t timestamp = AV_NOPTS_VALUE;
772 
773  parse_id3(pls->ctx, pb, &metadata, &timestamp, &apic, &extra_meta);
774 
775  if (timestamp != AV_NOPTS_VALUE) {
776  pls->id3_mpegts_timestamp = timestamp;
777  pls->id3_offset = 0;
778  }
779 
780  if (!pls->id3_found) {
781  /* initial ID3 tags */
783  pls->id3_found = 1;
784 
785  /* get picture attachment and set text metadata */
786  if (pls->ctx->nb_streams)
787  ff_id3v2_parse_apic(pls->ctx, &extra_meta);
788  else
789  /* demuxer not yet opened, defer picture attachment */
790  pls->id3_deferred_extra = extra_meta;
791 
792  av_dict_copy(&pls->ctx->metadata, metadata, 0);
793  pls->id3_initial = metadata;
794 
795  } else {
796  if (!pls->id3_changed && id3_has_changed_values(pls, metadata, apic)) {
797  avpriv_report_missing_feature(pls->ctx, "Changing ID3 metadata in HLS audio elementary stream");
798  pls->id3_changed = 1;
799  }
800  av_dict_free(&metadata);
801  }
802 
803  if (!pls->id3_deferred_extra)
804  ff_id3v2_free_extra_meta(&extra_meta);
805 }
806 
807 /* Intercept and handle ID3 tags between URLContext and AVIOContext */
808 static void intercept_id3(struct playlist *pls, uint8_t *buf,
809  int buf_size, int *len)
810 {
811  /* intercept id3 tags, we do not want to pass them to the raw
812  * demuxer on all segment switches */
813  int bytes;
814  int id3_buf_pos = 0;
815  int fill_buf = 0;
816 
817  /* gather all the id3 tags */
818  while (1) {
819  /* see if we can retrieve enough data for ID3 header */
820  if (*len < ID3v2_HEADER_SIZE && buf_size >= ID3v2_HEADER_SIZE) {
821  bytes = read_from_url(pls, buf + *len, ID3v2_HEADER_SIZE - *len, READ_COMPLETE);
822  if (bytes > 0) {
823 
824  if (bytes == ID3v2_HEADER_SIZE - *len)
825  /* no EOF yet, so fill the caller buffer again after
826  * we have stripped the ID3 tags */
827  fill_buf = 1;
828 
829  *len += bytes;
830 
831  } else if (*len <= 0) {
832  /* error/EOF */
833  *len = bytes;
834  fill_buf = 0;
835  }
836  }
837 
838  if (*len < ID3v2_HEADER_SIZE)
839  break;
840 
842  struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no];
843  int64_t maxsize = seg->size >= 0 ? seg->size : 1024*1024;
844  int taglen = ff_id3v2_tag_len(buf);
845  int tag_got_bytes = FFMIN(taglen, *len);
846  int remaining = taglen - tag_got_bytes;
847 
848  if (taglen > maxsize) {
849  av_log(pls->ctx, AV_LOG_ERROR, "Too large HLS ID3 tag (%d > %"PRId64" bytes)\n",
850  taglen, maxsize);
851  break;
852  }
853 
854  /*
855  * Copy the id3 tag to our temporary id3 buffer.
856  * We could read a small id3 tag directly without memcpy, but
857  * we would still need to copy the large tags, and handling
858  * both of those cases together with the possibility for multiple
859  * tags would make the handling a bit complex.
860  */
861  pls->id3_buf = av_fast_realloc(pls->id3_buf, &pls->id3_buf_size, id3_buf_pos + taglen);
862  if (!pls->id3_buf)
863  break;
864  memcpy(pls->id3_buf + id3_buf_pos, buf, tag_got_bytes);
865  id3_buf_pos += tag_got_bytes;
866 
867  /* strip the intercepted bytes */
868  *len -= tag_got_bytes;
869  memmove(buf, buf + tag_got_bytes, *len);
870  av_log(pls->ctx, AV_LOG_DEBUG, "Stripped %d HLS ID3 bytes\n", tag_got_bytes);
871 
872  if (remaining > 0) {
873  /* read the rest of the tag in */
874  if (read_from_url(pls, pls->id3_buf + id3_buf_pos, remaining, READ_COMPLETE) != remaining)
875  break;
876  id3_buf_pos += remaining;
877  av_log(pls->ctx, AV_LOG_DEBUG, "Stripped additional %d HLS ID3 bytes\n", remaining);
878  }
879 
880  } else {
881  /* no more ID3 tags */
882  break;
883  }
884  }
885 
886  /* re-fill buffer for the caller unless EOF */
887  if (*len >= 0 && (fill_buf || *len == 0)) {
888  bytes = read_from_url(pls, buf + *len, buf_size - *len, READ_NORMAL);
889 
890  /* ignore error if we already had some data */
891  if (bytes >= 0)
892  *len += bytes;
893  else if (*len == 0)
894  *len = bytes;
895  }
896 
897  if (pls->id3_buf) {
898  /* Now parse all the ID3 tags */
899  AVIOContext id3ioctx;
900  ffio_init_context(&id3ioctx, pls->id3_buf, id3_buf_pos, 0, NULL, NULL, NULL, NULL);
901  handle_id3(&id3ioctx, pls);
902  }
903 
904  if (pls->is_id3_timestamped == -1)
906 }
907 
908 static void update_options(char **dest, const char *name, void *src)
909 {
910  av_freep(dest);
911  av_opt_get(src, name, 0, (uint8_t**)dest);
912  if (*dest && !strlen(*dest))
913  av_freep(dest);
914 }
915 
916 static int open_input(HLSContext *c, struct playlist *pls)
917 {
918  AVDictionary *opts = NULL;
919  AVDictionary *opts2 = NULL;
920  int ret;
921  struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no];
922 
923  // broker prior HTTP options that should be consistent across requests
924  av_dict_set(&opts, "user-agent", c->user_agent, 0);
925  av_dict_set(&opts, "cookies", c->cookies, 0);
926  av_dict_set(&opts, "headers", c->headers, 0);
927  av_dict_set(&opts, "seekable", "0", 0);
928 
929  // Same opts for key request (ffurl_open mutilates the opts so it cannot be used twice)
930  av_dict_copy(&opts2, opts, 0);
931 
932  if (seg->size >= 0) {
933  /* try to restrict the HTTP request to the part we want
934  * (if this is in fact a HTTP request) */
935  av_dict_set_int(&opts, "offset", seg->url_offset, 0);
936  av_dict_set_int(&opts, "end_offset", seg->url_offset + seg->size, 0);
937  }
938 
939  av_log(pls->parent, AV_LOG_VERBOSE, "HLS request for url '%s', offset %"PRId64", playlist %d\n",
940  seg->url, seg->url_offset, pls->index);
941 
942  if (seg->key_type == KEY_NONE) {
943  ret = ffurl_open(&pls->input, seg->url, AVIO_FLAG_READ,
944  &pls->parent->interrupt_callback, &opts);
945 
946  } else if (seg->key_type == KEY_AES_128) {
947  char iv[33], key[33], url[MAX_URL_SIZE];
948  if (strcmp(seg->key, pls->key_url)) {
949  URLContext *uc;
950  if (ffurl_open(&uc, seg->key, AVIO_FLAG_READ,
951  &pls->parent->interrupt_callback, &opts2) == 0) {
952  if (ffurl_read_complete(uc, pls->key, sizeof(pls->key))
953  != sizeof(pls->key)) {
954  av_log(NULL, AV_LOG_ERROR, "Unable to read key file %s\n",
955  seg->key);
956  }
957  update_options(&c->cookies, "cookies", uc->priv_data);
958  av_dict_set(&opts, "cookies", c->cookies, 0);
959  ffurl_close(uc);
960  } else {
961  av_log(NULL, AV_LOG_ERROR, "Unable to open key file %s\n",
962  seg->key);
963  }
964  av_strlcpy(pls->key_url, seg->key, sizeof(pls->key_url));
965  }
966  ff_data_to_hex(iv, seg->iv, sizeof(seg->iv), 0);
967  ff_data_to_hex(key, pls->key, sizeof(pls->key), 0);
968  iv[32] = key[32] = '\0';
969  if (strstr(seg->url, "://"))
970  snprintf(url, sizeof(url), "crypto+%s", seg->url);
971  else
972  snprintf(url, sizeof(url), "crypto:%s", seg->url);
973  if ((ret = ffurl_alloc(&pls->input, url, AVIO_FLAG_READ,
974  &pls->parent->interrupt_callback)) < 0)
975  goto cleanup;
976  av_opt_set(pls->input->priv_data, "key", key, 0);
977  av_opt_set(pls->input->priv_data, "iv", iv, 0);
978 
979  if ((ret = ffurl_connect(pls->input, &opts)) < 0) {
980  ffurl_close(pls->input);
981  pls->input = NULL;
982  goto cleanup;
983  }
984  ret = 0;
985  } else if (seg->key_type == KEY_SAMPLE_AES) {
986  av_log(pls->parent, AV_LOG_ERROR,
987  "SAMPLE-AES encryption is not supported yet\n");
988  ret = AVERROR_PATCHWELCOME;
989  }
990  else
991  ret = AVERROR(ENOSYS);
992 
993  /* Seek to the requested position. If this was a HTTP request, the offset
994  * should already be where want it to, but this allows e.g. local testing
995  * without a HTTP server. */
996  if (ret == 0 && seg->key_type == KEY_NONE) {
997  int seekret = ffurl_seek(pls->input, seg->url_offset, SEEK_SET);
998  if (seekret < 0) {
999  av_log(pls->parent, AV_LOG_ERROR, "Unable to seek to offset %"PRId64" of HLS segment '%s'\n", seg->url_offset, seg->url);
1000  ret = seekret;
1001  ffurl_close(pls->input);
1002  pls->input = NULL;
1003  }
1004  }
1005 
1006 cleanup:
1007  av_dict_free(&opts);
1008  av_dict_free(&opts2);
1009  pls->cur_seg_offset = 0;
1010  return ret;
1011 }
1012 
1013 static int64_t default_reload_interval(struct playlist *pls)
1014 {
1015  return pls->n_segments > 0 ?
1016  pls->segments[pls->n_segments - 1]->duration :
1017  pls->target_duration;
1018 }
1019 
1020 static int read_data(void *opaque, uint8_t *buf, int buf_size)
1021 {
1022  struct playlist *v = opaque;
1023  HLSContext *c = v->parent->priv_data;
1024  int ret, i;
1025  int just_opened = 0;
1026 
1027 restart:
1028  if (!v->needed)
1029  return AVERROR_EOF;
1030 
1031  if (!v->input) {
1032  int64_t reload_interval;
1033 
1034  /* Check that the playlist is still needed before opening a new
1035  * segment. */
1036  if (v->ctx && v->ctx->nb_streams &&
1037  v->parent->nb_streams >= v->stream_offset + v->ctx->nb_streams) {
1038  v->needed = 0;
1039  for (i = v->stream_offset; i < v->stream_offset + v->ctx->nb_streams;
1040  i++) {
1041  if (v->parent->streams[i]->discard < AVDISCARD_ALL)
1042  v->needed = 1;
1043  }
1044  }
1045  if (!v->needed) {
1046  av_log(v->parent, AV_LOG_INFO, "No longer receiving playlist %d\n",
1047  v->index);
1048  return AVERROR_EOF;
1049  }
1050 
1051  /* If this is a live stream and the reload interval has elapsed since
1052  * the last playlist reload, reload the playlists now. */
1053  reload_interval = default_reload_interval(v);
1054 
1055 reload:
1056  if (!v->finished &&
1057  av_gettime_relative() - v->last_load_time >= reload_interval) {
1058  if ((ret = parse_playlist(c, v->url, v, NULL)) < 0) {
1059  av_log(v->parent, AV_LOG_WARNING, "Failed to reload playlist %d\n",
1060  v->index);
1061  return ret;
1062  }
1063  /* If we need to reload the playlist again below (if
1064  * there's still no more segments), switch to a reload
1065  * interval of half the target duration. */
1066  reload_interval = v->target_duration / 2;
1067  }
1068  if (v->cur_seq_no < v->start_seq_no) {
1070  "skipping %d segments ahead, expired from playlists\n",
1071  v->start_seq_no - v->cur_seq_no);
1072  v->cur_seq_no = v->start_seq_no;
1073  }
1074  if (v->cur_seq_no >= v->start_seq_no + v->n_segments) {
1075  if (v->finished)
1076  return AVERROR_EOF;
1077  while (av_gettime_relative() - v->last_load_time < reload_interval) {
1079  return AVERROR_EXIT;
1080  av_usleep(100*1000);
1081  }
1082  /* Enough time has elapsed since the last reload */
1083  goto reload;
1084  }
1085 
1086  ret = open_input(c, v);
1087  if (ret < 0) {
1088  av_log(v->parent, AV_LOG_WARNING, "Failed to open segment of playlist %d\n",
1089  v->index);
1090  v->cur_seq_no += 1;
1091  goto reload;
1092  }
1093  just_opened = 1;
1094  }
1095 
1096  ret = read_from_url(v, buf, buf_size, READ_NORMAL);
1097  if (ret > 0) {
1098  if (just_opened && v->is_id3_timestamped != 0) {
1099  /* Intercept ID3 tags here, elementary audio streams are required
1100  * to convey timestamps using them in the beginning of each segment. */
1101  intercept_id3(v, buf, buf_size, &ret);
1102  }
1103 
1104  return ret;
1105  }
1106  ffurl_close(v->input);
1107  v->input = NULL;
1108  v->cur_seq_no++;
1109 
1110  c->cur_seq_no = v->cur_seq_no;
1111 
1112  goto restart;
1113 }
1114 
1116 {
1117  int variant_count = 0;
1118  int i, j;
1119 
1120  for (i = 0; i < c->n_variants && variant_count < 2; i++) {
1121  struct variant *v = c->variants[i];
1122 
1123  for (j = 0; j < v->n_playlists; j++) {
1124  if (v->playlists[j] == pls) {
1125  variant_count++;
1126  break;
1127  }
1128  }
1129  }
1130 
1131  return variant_count >= 2;
1132 }
1133 
1134 static void add_renditions_to_variant(HLSContext *c, struct variant *var,
1135  enum AVMediaType type, const char *group_id)
1136 {
1137  int i;
1138 
1139  for (i = 0; i < c->n_renditions; i++) {
1140  struct rendition *rend = c->renditions[i];
1141 
1142  if (rend->type == type && !strcmp(rend->group_id, group_id)) {
1143 
1144  if (rend->playlist)
1145  /* rendition is an external playlist
1146  * => add the playlist to the variant */
1147  dynarray_add(&var->playlists, &var->n_playlists, rend->playlist);
1148  else
1149  /* rendition is part of the variant main Media Playlist
1150  * => add the rendition to the main Media Playlist */
1151  dynarray_add(&var->playlists[0]->renditions,
1152  &var->playlists[0]->n_renditions,
1153  rend);
1154  }
1155  }
1156 }
1157 
1159  enum AVMediaType type)
1160 {
1161  int rend_idx = 0;
1162  int i;
1163 
1164  for (i = 0; i < pls->ctx->nb_streams; i++) {
1165  AVStream *st = s->streams[pls->stream_offset + i];
1166 
1167  if (st->codec->codec_type != type)
1168  continue;
1169 
1170  for (; rend_idx < pls->n_renditions; rend_idx++) {
1171  struct rendition *rend = pls->renditions[rend_idx];
1172 
1173  if (rend->type != type)
1174  continue;
1175 
1176  if (rend->language[0])
1177  av_dict_set(&st->metadata, "language", rend->language, 0);
1178  if (rend->name[0])
1179  av_dict_set(&st->metadata, "comment", rend->name, 0);
1180 
1181  st->disposition |= rend->disposition;
1182  }
1183  if (rend_idx >=pls->n_renditions)
1184  break;
1185  }
1186 }
1187 
1188 /* if timestamp was in valid range: returns 1 and sets seq_no
1189  * if not: returns 0 and sets seq_no to closest segment */
1191  int64_t timestamp, int *seq_no)
1192 {
1193  int i;
1194  int64_t pos = c->first_timestamp == AV_NOPTS_VALUE ?
1195  0 : c->first_timestamp;
1196 
1197  if (timestamp < pos) {
1198  *seq_no = pls->start_seq_no;
1199  return 0;
1200  }
1201 
1202  for (i = 0; i < pls->n_segments; i++) {
1203  int64_t diff = pos + pls->segments[i]->duration - timestamp;
1204  if (diff > 0) {
1205  *seq_no = pls->start_seq_no + i;
1206  return 1;
1207  }
1208  pos += pls->segments[i]->duration;
1209  }
1210 
1211  *seq_no = pls->start_seq_no + pls->n_segments - 1;
1212 
1213  return 0;
1214 }
1215 
1216 static int select_cur_seq_no(HLSContext *c, struct playlist *pls)
1217 {
1218  int seq_no;
1219 
1220  if (!pls->finished && !c->first_packet &&
1222  /* reload the playlist since it was suspended */
1223  parse_playlist(c, pls->url, pls, NULL);
1224 
1225  /* If playback is already in progress (we are just selecting a new
1226  * playlist) and this is a complete file, find the matching segment
1227  * by counting durations. */
1228  if (pls->finished && c->cur_timestamp != AV_NOPTS_VALUE) {
1229  find_timestamp_in_playlist(c, pls, c->cur_timestamp, &seq_no);
1230  return seq_no;
1231  }
1232 
1233  if (!pls->finished) {
1234  if (!c->first_packet && /* we are doing a segment selection during playback */
1235  c->cur_seq_no >= pls->start_seq_no &&
1236  c->cur_seq_no < pls->start_seq_no + pls->n_segments)
1237  /* While spec 3.4.3 says that we cannot assume anything about the
1238  * content at the same sequence number on different playlists,
1239  * in practice this seems to work and doing it otherwise would
1240  * require us to download a segment to inspect its timestamps. */
1241  return c->cur_seq_no;
1242 
1243  /* If this is a live stream, start live_start_index segments from the
1244  * start or end */
1245  if (c->live_start_index < 0)
1246  return pls->start_seq_no + FFMAX(pls->n_segments + c->live_start_index, 0);
1247  else
1248  return pls->start_seq_no + FFMIN(c->live_start_index, pls->n_segments - 1);
1249  }
1250 
1251  /* Otherwise just start on the first segment. */
1252  return pls->start_seq_no;
1253 }
1254 
1256 {
1257  URLContext *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb->opaque;
1258  HLSContext *c = s->priv_data;
1259  int ret = 0, i, j, stream_offset = 0;
1260 
1261  c->interrupt_callback = &s->interrupt_callback;
1262 
1263  c->first_packet = 1;
1264  c->first_timestamp = AV_NOPTS_VALUE;
1265  c->cur_timestamp = AV_NOPTS_VALUE;
1266 
1267  // if the URL context is good, read important options we must broker later
1268  if (u && u->prot->priv_data_class) {
1269  // get the previous user agent & set back to null if string size is zero
1270  update_options(&c->user_agent, "user-agent", u->priv_data);
1271 
1272  // get the previous cookies & set back to null if string size is zero
1273  update_options(&c->cookies, "cookies", u->priv_data);
1274 
1275  // get the previous headers & set back to null if string size is zero
1276  update_options(&c->headers, "headers", u->priv_data);
1277  }
1278 
1279  if ((ret = parse_playlist(c, s->filename, NULL, s->pb)) < 0)
1280  goto fail;
1281 
1282  if (c->n_variants == 0) {
1283  av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
1284  ret = AVERROR_EOF;
1285  goto fail;
1286  }
1287  /* If the playlist only contained playlists (Master Playlist),
1288  * parse each individual playlist. */
1289  if (c->n_playlists > 1 || c->playlists[0]->n_segments == 0) {
1290  for (i = 0; i < c->n_playlists; i++) {
1291  struct playlist *pls = c->playlists[i];
1292  if ((ret = parse_playlist(c, pls->url, pls, NULL)) < 0)
1293  goto fail;
1294  }
1295  }
1296 
1297  if (c->variants[0]->playlists[0]->n_segments == 0) {
1298  av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
1299  ret = AVERROR_EOF;
1300  goto fail;
1301  }
1302 
1303  /* If this isn't a live stream, calculate the total duration of the
1304  * stream. */
1305  if (c->variants[0]->playlists[0]->finished) {
1306  int64_t duration = 0;
1307  for (i = 0; i < c->variants[0]->playlists[0]->n_segments; i++)
1308  duration += c->variants[0]->playlists[0]->segments[i]->duration;
1309  s->duration = duration;
1310  }
1311 
1312  /* Associate renditions with variants */
1313  for (i = 0; i < c->n_variants; i++) {
1314  struct variant *var = c->variants[i];
1315 
1316  if (var->audio_group[0])
1318  if (var->video_group[0])
1320  if (var->subtitles_group[0])
1322  }
1323 
1324  /* Open the demuxer for each playlist */
1325  for (i = 0; i < c->n_playlists; i++) {
1326  struct playlist *pls = c->playlists[i];
1327  AVInputFormat *in_fmt = NULL;
1328 
1329  if (!(pls->ctx = avformat_alloc_context())) {
1330  ret = AVERROR(ENOMEM);
1331  goto fail;
1332  }
1333 
1334  if (pls->n_segments == 0)
1335  continue;
1336 
1337  pls->index = i;
1338  pls->needed = 1;
1339  pls->parent = s;
1340  pls->cur_seq_no = select_cur_seq_no(c, pls);
1341 
1343  if (!pls->read_buffer){
1344  ret = AVERROR(ENOMEM);
1345  avformat_free_context(pls->ctx);
1346  pls->ctx = NULL;
1347  goto fail;
1348  }
1349  ffio_init_context(&pls->pb, pls->read_buffer, INITIAL_BUFFER_SIZE, 0, pls,
1350  read_data, NULL, NULL);
1351  pls->pb.seekable = 0;
1352  ret = av_probe_input_buffer(&pls->pb, &in_fmt, pls->segments[0]->url,
1353  NULL, 0, 0);
1354  if (ret < 0) {
1355  /* Free the ctx - it isn't initialized properly at this point,
1356  * so avformat_close_input shouldn't be called. If
1357  * avformat_open_input fails below, it frees and zeros the
1358  * context, so it doesn't need any special treatment like this. */
1359  av_log(s, AV_LOG_ERROR, "Error when loading first segment '%s'\n", pls->segments[0]->url);
1360  avformat_free_context(pls->ctx);
1361  pls->ctx = NULL;
1362  goto fail;
1363  }
1364  pls->ctx->pb = &pls->pb;
1366 
1367  if ((ret = ff_copy_whitelists(pls->ctx, s)) < 0)
1368  goto fail;
1369 
1370  ret = avformat_open_input(&pls->ctx, pls->segments[0]->url, in_fmt, NULL);
1371  if (ret < 0)
1372  goto fail;
1373 
1374  if (pls->id3_deferred_extra && pls->ctx->nb_streams == 1) {
1378  pls->id3_deferred_extra = NULL;
1379  }
1380 
1381  pls->ctx->ctx_flags &= ~AVFMTCTX_NOHEADER;
1383  if (ret < 0)
1384  goto fail;
1385 
1386  if (pls->is_id3_timestamped == -1)
1387  av_log(s, AV_LOG_WARNING, "No expected HTTP requests have been made\n");
1388 
1389  /* Create new AVStreams for each stream in this playlist */
1390  for (j = 0; j < pls->ctx->nb_streams; j++) {
1391  AVStream *st = avformat_new_stream(s, NULL);
1392  AVStream *ist = pls->ctx->streams[j];
1393  if (!st) {
1394  ret = AVERROR(ENOMEM);
1395  goto fail;
1396  }
1397  st->id = i;
1398 
1399  avcodec_copy_context(st->codec, pls->ctx->streams[j]->codec);
1400 
1401  if (pls->is_id3_timestamped) /* custom timestamps via id3 */
1402  avpriv_set_pts_info(st, 33, 1, MPEG_TIME_BASE);
1403  else
1405  }
1406 
1410 
1411  stream_offset += pls->ctx->nb_streams;
1412  }
1413 
1414  /* Create a program for each variant */
1415  for (i = 0; i < c->n_variants; i++) {
1416  struct variant *v = c->variants[i];
1417  AVProgram *program;
1418 
1419  program = av_new_program(s, i);
1420  if (!program)
1421  goto fail;
1422  av_dict_set_int(&program->metadata, "variant_bitrate", v->bandwidth, 0);
1423 
1424  for (j = 0; j < v->n_playlists; j++) {
1425  struct playlist *pls = v->playlists[j];
1426  int is_shared = playlist_in_multiple_variants(c, pls);
1427  int k;
1428 
1429  for (k = 0; k < pls->ctx->nb_streams; k++) {
1430  struct AVStream *st = s->streams[pls->stream_offset + k];
1431 
1433 
1434  /* Set variant_bitrate for streams unique to this variant */
1435  if (!is_shared && v->bandwidth)
1436  av_dict_set_int(&st->metadata, "variant_bitrate", v->bandwidth, 0);
1437  }
1438  }
1439  }
1440 
1441  return 0;
1442 fail:
1446  return ret;
1447 }
1448 
1449 static int recheck_discard_flags(AVFormatContext *s, int first)
1450 {
1451  HLSContext *c = s->priv_data;
1452  int i, changed = 0;
1453 
1454  /* Check if any new streams are needed */
1455  for (i = 0; i < c->n_playlists; i++)
1456  c->playlists[i]->cur_needed = 0;
1457 
1458  for (i = 0; i < s->nb_streams; i++) {
1459  AVStream *st = s->streams[i];
1460  struct playlist *pls = c->playlists[s->streams[i]->id];
1461  if (st->discard < AVDISCARD_ALL)
1462  pls->cur_needed = 1;
1463  }
1464  for (i = 0; i < c->n_playlists; i++) {
1465  struct playlist *pls = c->playlists[i];
1466  if (pls->cur_needed && !pls->needed) {
1467  pls->needed = 1;
1468  changed = 1;
1469  pls->cur_seq_no = select_cur_seq_no(c, pls);
1470  pls->pb.eof_reached = 0;
1471  if (c->cur_timestamp != AV_NOPTS_VALUE) {
1472  /* catch up */
1473  pls->seek_timestamp = c->cur_timestamp;
1474  pls->seek_flags = AVSEEK_FLAG_ANY;
1475  pls->seek_stream_index = -1;
1476  }
1477  av_log(s, AV_LOG_INFO, "Now receiving playlist %d, segment %d\n", i, pls->cur_seq_no);
1478  } else if (first && !pls->cur_needed && pls->needed) {
1479  if (pls->input)
1480  ffurl_close(pls->input);
1481  pls->input = NULL;
1482  pls->needed = 0;
1483  changed = 1;
1484  av_log(s, AV_LOG_INFO, "No longer receiving playlist %d\n", i);
1485  }
1486  }
1487  return changed;
1488 }
1489 
1491 {
1492  if (pls->id3_offset >= 0) {
1493  pls->pkt.dts = pls->id3_mpegts_timestamp +
1494  av_rescale_q(pls->id3_offset,
1495  pls->ctx->streams[pls->pkt.stream_index]->time_base,
1497  if (pls->pkt.duration)
1498  pls->id3_offset += pls->pkt.duration;
1499  else
1500  pls->id3_offset = -1;
1501  } else {
1502  /* there have been packets with unknown duration
1503  * since the last id3 tag, should not normally happen */
1504  pls->pkt.dts = AV_NOPTS_VALUE;
1505  }
1506 
1507  if (pls->pkt.duration)
1508  pls->pkt.duration = av_rescale_q(pls->pkt.duration,
1509  pls->ctx->streams[pls->pkt.stream_index]->time_base,
1511 
1512  pls->pkt.pts = AV_NOPTS_VALUE;
1513 }
1514 
1515 static AVRational get_timebase(struct playlist *pls)
1516 {
1517  if (pls->is_id3_timestamped)
1518  return MPEG_TIME_BASE_Q;
1519 
1520  return pls->ctx->streams[pls->pkt.stream_index]->time_base;
1521 }
1522 
1523 static int compare_ts_with_wrapdetect(int64_t ts_a, struct playlist *pls_a,
1524  int64_t ts_b, struct playlist *pls_b)
1525 {
1526  int64_t scaled_ts_a = av_rescale_q(ts_a, get_timebase(pls_a), MPEG_TIME_BASE_Q);
1527  int64_t scaled_ts_b = av_rescale_q(ts_b, get_timebase(pls_b), MPEG_TIME_BASE_Q);
1528 
1529  return av_compare_mod(scaled_ts_a, scaled_ts_b, 1LL << 33);
1530 }
1531 
1533 {
1534  HLSContext *c = s->priv_data;
1535  int ret, i, minplaylist = -1;
1536 
1538 
1539  for (i = 0; i < c->n_playlists; i++) {
1540  struct playlist *pls = c->playlists[i];
1541  /* Make sure we've got one buffered packet from each open playlist
1542  * stream */
1543  if (pls->needed && !pls->pkt.data) {
1544  while (1) {
1545  int64_t ts_diff;
1546  AVRational tb;
1547  ret = av_read_frame(pls->ctx, &pls->pkt);
1548  if (ret < 0) {
1549  if (!avio_feof(&pls->pb) && ret != AVERROR_EOF)
1550  return ret;
1551  reset_packet(&pls->pkt);
1552  break;
1553  } else {
1554  /* stream_index check prevents matching picture attachments etc. */
1555  if (pls->is_id3_timestamped && pls->pkt.stream_index == 0) {
1556  /* audio elementary streams are id3 timestamped */
1558  }
1559 
1560  if (c->first_timestamp == AV_NOPTS_VALUE &&
1561  pls->pkt.dts != AV_NOPTS_VALUE)
1562  c->first_timestamp = av_rescale_q(pls->pkt.dts,
1564  }
1565 
1566  if (pls->seek_timestamp == AV_NOPTS_VALUE)
1567  break;
1568 
1569  if (pls->seek_stream_index < 0 ||
1570  pls->seek_stream_index == pls->pkt.stream_index) {
1571 
1572  if (pls->pkt.dts == AV_NOPTS_VALUE) {
1574  break;
1575  }
1576 
1577  tb = get_timebase(pls);
1578  ts_diff = av_rescale_rnd(pls->pkt.dts, AV_TIME_BASE,
1579  tb.den, AV_ROUND_DOWN) -
1580  pls->seek_timestamp;
1581  if (ts_diff >= 0 && (pls->seek_flags & AVSEEK_FLAG_ANY ||
1582  pls->pkt.flags & AV_PKT_FLAG_KEY)) {
1584  break;
1585  }
1586  }
1587  av_free_packet(&pls->pkt);
1588  reset_packet(&pls->pkt);
1589  }
1590  }
1591  /* Check if this stream has the packet with the lowest dts */
1592  if (pls->pkt.data) {
1593  struct playlist *minpls = minplaylist < 0 ?
1594  NULL : c->playlists[minplaylist];
1595  if (minplaylist < 0) {
1596  minplaylist = i;
1597  } else {
1598  int64_t dts = pls->pkt.dts;
1599  int64_t mindts = minpls->pkt.dts;
1600 
1601  if (dts == AV_NOPTS_VALUE ||
1602  (mindts != AV_NOPTS_VALUE && compare_ts_with_wrapdetect(dts, pls, mindts, minpls) < 0))
1603  minplaylist = i;
1604  }
1605  }
1606  }
1607 
1608  /* If we got a packet, return it */
1609  if (minplaylist >= 0) {
1610  struct playlist *pls = c->playlists[minplaylist];
1611  *pkt = pls->pkt;
1612  pkt->stream_index += pls->stream_offset;
1613  reset_packet(&c->playlists[minplaylist]->pkt);
1614 
1615  if (pkt->dts != AV_NOPTS_VALUE)
1616  c->cur_timestamp = av_rescale_q(pkt->dts,
1617  pls->ctx->streams[pls->pkt.stream_index]->time_base,
1618  AV_TIME_BASE_Q);
1619 
1620  return 0;
1621  }
1622  return AVERROR_EOF;
1623 }
1624 
1626 {
1627  HLSContext *c = s->priv_data;
1628 
1629  free_playlist_list(c);
1630  free_variant_list(c);
1632  return 0;
1633 }
1634 
1635 static int hls_read_seek(AVFormatContext *s, int stream_index,
1636  int64_t timestamp, int flags)
1637 {
1638  HLSContext *c = s->priv_data;
1639  struct playlist *seek_pls = NULL;
1640  int i, seq_no;
1641  int64_t first_timestamp, seek_timestamp, duration;
1642 
1643  if ((flags & AVSEEK_FLAG_BYTE) ||
1644  !(c->variants[0]->playlists[0]->finished || c->variants[0]->playlists[0]->type == PLS_TYPE_EVENT))
1645  return AVERROR(ENOSYS);
1646 
1647  first_timestamp = c->first_timestamp == AV_NOPTS_VALUE ?
1648  0 : c->first_timestamp;
1649 
1650  seek_timestamp = av_rescale_rnd(timestamp, AV_TIME_BASE,
1651  s->streams[stream_index]->time_base.den,
1652  flags & AVSEEK_FLAG_BACKWARD ?
1654 
1655  duration = s->duration == AV_NOPTS_VALUE ?
1656  0 : s->duration;
1657 
1658  if (0 < duration && duration < seek_timestamp - first_timestamp)
1659  return AVERROR(EIO);
1660 
1661  /* find the playlist with the specified stream */
1662  for (i = 0; i < c->n_playlists; i++) {
1663  struct playlist *pls = c->playlists[i];
1664  if (stream_index >= pls->stream_offset &&
1665  stream_index - pls->stream_offset < pls->ctx->nb_streams) {
1666  seek_pls = pls;
1667  break;
1668  }
1669  }
1670  /* check if the timestamp is valid for the playlist with the
1671  * specified stream index */
1672  if (!seek_pls || !find_timestamp_in_playlist(c, seek_pls, seek_timestamp, &seq_no))
1673  return AVERROR(EIO);
1674 
1675  /* set segment now so we do not need to search again below */
1676  seek_pls->cur_seq_no = seq_no;
1677  seek_pls->seek_stream_index = stream_index - seek_pls->stream_offset;
1678 
1679  for (i = 0; i < c->n_playlists; i++) {
1680  /* Reset reading */
1681  struct playlist *pls = c->playlists[i];
1682  if (pls->input) {
1683  ffurl_close(pls->input);
1684  pls->input = NULL;
1685  }
1686  av_free_packet(&pls->pkt);
1687  reset_packet(&pls->pkt);
1688  pls->pb.eof_reached = 0;
1689  /* Clear any buffered data */
1690  pls->pb.buf_end = pls->pb.buf_ptr = pls->pb.buffer;
1691  /* Reset the pos, to let the mpegts demuxer know we've seeked. */
1692  pls->pb.pos = 0;
1693  /* Flush the packet queue of the subdemuxer. */
1694  ff_read_frame_flush(pls->ctx);
1695 
1697  pls->seek_flags = flags;
1698 
1699  if (pls != seek_pls) {
1700  /* set closest segment seq_no for playlists not handled above */
1701  find_timestamp_in_playlist(c, pls, seek_timestamp, &pls->cur_seq_no);
1702  /* seek the playlist to the given position without taking
1703  * keyframes into account since this playlist does not have the
1704  * specified stream where we should look for the keyframes */
1705  pls->seek_stream_index = -1;
1706  pls->seek_flags |= AVSEEK_FLAG_ANY;
1707  }
1708  }
1709 
1711 
1712  return 0;
1713 }
1714 
1715 static int hls_probe(AVProbeData *p)
1716 {
1717  /* Require #EXTM3U at the start, and either one of the ones below
1718  * somewhere for a proper match. */
1719  if (strncmp(p->buf, "#EXTM3U", 7))
1720  return 0;
1721  if (strstr(p->buf, "#EXT-X-STREAM-INF:") ||
1722  strstr(p->buf, "#EXT-X-TARGETDURATION:") ||
1723  strstr(p->buf, "#EXT-X-MEDIA-SEQUENCE:"))
1724  return AVPROBE_SCORE_MAX;
1725  return 0;
1726 }
1727 
1728 #define OFFSET(x) offsetof(HLSContext, x)
1729 #define FLAGS AV_OPT_FLAG_DECODING_PARAM
1730 static const AVOption hls_options[] = {
1731  {"live_start_index", "segment index to start live streams at (negative values are from the end)",
1732  OFFSET(live_start_index), FF_OPT_TYPE_INT, {.i64 = -3}, INT_MIN, INT_MAX, FLAGS},
1733  {NULL}
1734 };
1735 
1736 static const AVClass hls_class = {
1737  .class_name = "hls,applehttp",
1738  .item_name = av_default_item_name,
1739  .option = hls_options,
1740  .version = LIBAVUTIL_VERSION_INT,
1741 };
1742 
1744  .name = "hls,applehttp",
1745  .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),
1746  .priv_class = &hls_class,
1747  .priv_data_size = sizeof(HLSContext),
1748  .read_probe = hls_probe,
1751  .read_close = hls_close,
1753 };