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hls.c
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1 /*
2  * Apple HTTP Live Streaming demuxer
3  * Copyright (c) 2010 Martin Storsjo
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 /**
23  * @file
24  * Apple HTTP Live Streaming demuxer
25  * http://tools.ietf.org/html/draft-pantos-http-live-streaming
26  */
27 
28 #include "libavutil/avstring.h"
29 #include "libavutil/intreadwrite.h"
30 #include "libavutil/mathematics.h"
31 #include "libavutil/opt.h"
32 #include "libavutil/dict.h"
33 #include "libavutil/time.h"
34 #include "avformat.h"
35 #include "internal.h"
36 #include "avio_internal.h"
37 #include "url.h"
38 
39 #define INITIAL_BUFFER_SIZE 32768
40 
41 /*
42  * An apple http stream consists of a playlist with media segment files,
43  * played sequentially. There may be several playlists with the same
44  * video content, in different bandwidth variants, that are played in
45  * parallel (preferably only one bandwidth variant at a time). In this case,
46  * the user supplied the url to a main playlist that only lists the variant
47  * playlists.
48  *
49  * If the main playlist doesn't point at any variants, we still create
50  * one anonymous toplevel variant for this, to maintain the structure.
51  */
52 
53 enum KeyType {
56 };
57 
58 struct segment {
59  int64_t duration;
63  uint8_t iv[16];
64 };
65 
66 /*
67  * Each variant has its own demuxer. If it currently is active,
68  * it has an open AVIOContext too, and potentially an AVPacket
69  * containing the next packet from this stream.
70  */
71 struct variant {
72  int bandwidth;
78  int index;
82 
83  int finished;
84  int64_t target_duration;
87  struct segment **segments;
90  int64_t last_load_time;
91 
93  uint8_t key[16];
94 };
95 
96 typedef struct HLSContext {
98  struct variant **variants;
103  int64_t seek_timestamp;
106  char *user_agent; ///< holds HTTP user agent set as an AVOption to the HTTP protocol context
107  char *cookies; ///< holds HTTP cookie values set in either the initial response or as an AVOption to the HTTP protocol context
108 } HLSContext;
109 
110 static int read_chomp_line(AVIOContext *s, char *buf, int maxlen)
111 {
112  int len = ff_get_line(s, buf, maxlen);
113  while (len > 0 && av_isspace(buf[len - 1]))
114  buf[--len] = '\0';
115  return len;
116 }
117 
118 static void free_segment_list(struct variant *var)
119 {
120  int i;
121  for (i = 0; i < var->n_segments; i++)
122  av_free(var->segments[i]);
123  av_freep(&var->segments);
124  var->n_segments = 0;
125 }
126 
128 {
129  int i;
130  for (i = 0; i < c->n_variants; i++) {
131  struct variant *var = c->variants[i];
132  free_segment_list(var);
133  av_free_packet(&var->pkt);
134  av_free(var->pb.buffer);
135  if (var->input)
136  ffurl_close(var->input);
137  if (var->ctx) {
138  var->ctx->pb = NULL;
139  avformat_close_input(&var->ctx);
140  }
141  av_free(var);
142  }
143  av_freep(&c->variants);
144  av_freep(&c->cookies);
145  av_freep(&c->user_agent);
146  c->n_variants = 0;
147 }
148 
149 /*
150  * Used to reset a statically allocated AVPacket to a clean slate,
151  * containing no data.
152  */
153 static void reset_packet(AVPacket *pkt)
154 {
155  av_init_packet(pkt);
156  pkt->data = NULL;
157 }
158 
159 static struct variant *new_variant(HLSContext *c, int bandwidth,
160  const char *url, const char *base)
161 {
162  struct variant *var = av_mallocz(sizeof(struct variant));
163  if (!var)
164  return NULL;
165  reset_packet(&var->pkt);
166  var->bandwidth = bandwidth;
167  ff_make_absolute_url(var->url, sizeof(var->url), base, url);
168  dynarray_add(&c->variants, &c->n_variants, var);
169  return var;
170 }
171 
172 struct variant_info {
173  char bandwidth[20];
174 };
175 
176 static void handle_variant_args(struct variant_info *info, const char *key,
177  int key_len, char **dest, int *dest_len)
178 {
179  if (!strncmp(key, "BANDWIDTH=", key_len)) {
180  *dest = info->bandwidth;
181  *dest_len = sizeof(info->bandwidth);
182  }
183 }
184 
185 struct key_info {
187  char method[10];
188  char iv[35];
189 };
190 
191 static void handle_key_args(struct key_info *info, const char *key,
192  int key_len, char **dest, int *dest_len)
193 {
194  if (!strncmp(key, "METHOD=", key_len)) {
195  *dest = info->method;
196  *dest_len = sizeof(info->method);
197  } else if (!strncmp(key, "URI=", key_len)) {
198  *dest = info->uri;
199  *dest_len = sizeof(info->uri);
200  } else if (!strncmp(key, "IV=", key_len)) {
201  *dest = info->iv;
202  *dest_len = sizeof(info->iv);
203  }
204 }
205 
206 static int parse_playlist(HLSContext *c, const char *url,
207  struct variant *var, AVIOContext *in)
208 {
209  int ret = 0, is_segment = 0, is_variant = 0, bandwidth = 0;
210  int64_t duration = 0;
211  enum KeyType key_type = KEY_NONE;
212  uint8_t iv[16] = "";
213  int has_iv = 0;
214  char key[MAX_URL_SIZE] = "";
215  char line[MAX_URL_SIZE];
216  const char *ptr;
217  int close_in = 0;
218 
219  if (!in) {
220  AVDictionary *opts = NULL;
221  close_in = 1;
222  /* Some HLS servers don't like being sent the range header */
223  av_dict_set(&opts, "seekable", "0", 0);
224 
225  // broker prior HTTP options that should be consistent across requests
226  av_dict_set(&opts, "user-agent", c->user_agent, 0);
227  av_dict_set(&opts, "cookies", c->cookies, 0);
228 
229  ret = avio_open2(&in, url, AVIO_FLAG_READ,
230  c->interrupt_callback, &opts);
231  av_dict_free(&opts);
232  if (ret < 0)
233  return ret;
234  }
235 
236  read_chomp_line(in, line, sizeof(line));
237  if (strcmp(line, "#EXTM3U")) {
238  ret = AVERROR_INVALIDDATA;
239  goto fail;
240  }
241 
242  if (var) {
243  free_segment_list(var);
244  var->finished = 0;
245  }
246  while (!url_feof(in)) {
247  read_chomp_line(in, line, sizeof(line));
248  if (av_strstart(line, "#EXT-X-STREAM-INF:", &ptr)) {
249  struct variant_info info = {{0}};
250  is_variant = 1;
252  &info);
253  bandwidth = atoi(info.bandwidth);
254  } else if (av_strstart(line, "#EXT-X-KEY:", &ptr)) {
255  struct key_info info = {{0}};
257  &info);
258  key_type = KEY_NONE;
259  has_iv = 0;
260  if (!strcmp(info.method, "AES-128"))
261  key_type = KEY_AES_128;
262  if (!strncmp(info.iv, "0x", 2) || !strncmp(info.iv, "0X", 2)) {
263  ff_hex_to_data(iv, info.iv + 2);
264  has_iv = 1;
265  }
266  av_strlcpy(key, info.uri, sizeof(key));
267  } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) {
268  if (!var) {
269  var = new_variant(c, 0, url, NULL);
270  if (!var) {
271  ret = AVERROR(ENOMEM);
272  goto fail;
273  }
274  }
275  var->target_duration = atoi(ptr) * AV_TIME_BASE;
276  } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) {
277  if (!var) {
278  var = new_variant(c, 0, url, NULL);
279  if (!var) {
280  ret = AVERROR(ENOMEM);
281  goto fail;
282  }
283  }
284  var->start_seq_no = atoi(ptr);
285  } else if (av_strstart(line, "#EXT-X-ENDLIST", &ptr)) {
286  if (var)
287  var->finished = 1;
288  } else if (av_strstart(line, "#EXTINF:", &ptr)) {
289  is_segment = 1;
290  duration = atof(ptr) * AV_TIME_BASE;
291  } else if (av_strstart(line, "#", NULL)) {
292  continue;
293  } else if (line[0]) {
294  if (is_variant) {
295  if (!new_variant(c, bandwidth, line, url)) {
296  ret = AVERROR(ENOMEM);
297  goto fail;
298  }
299  is_variant = 0;
300  bandwidth = 0;
301  }
302  if (is_segment) {
303  struct segment *seg;
304  if (!var) {
305  var = new_variant(c, 0, url, NULL);
306  if (!var) {
307  ret = AVERROR(ENOMEM);
308  goto fail;
309  }
310  }
311  seg = av_malloc(sizeof(struct segment));
312  if (!seg) {
313  ret = AVERROR(ENOMEM);
314  goto fail;
315  }
316  seg->duration = duration;
317  seg->key_type = key_type;
318  if (has_iv) {
319  memcpy(seg->iv, iv, sizeof(iv));
320  } else {
321  int seq = var->start_seq_no + var->n_segments;
322  memset(seg->iv, 0, sizeof(seg->iv));
323  AV_WB32(seg->iv + 12, seq);
324  }
325  ff_make_absolute_url(seg->key, sizeof(seg->key), url, key);
326  ff_make_absolute_url(seg->url, sizeof(seg->url), url, line);
327  dynarray_add(&var->segments, &var->n_segments, seg);
328  is_segment = 0;
329  }
330  }
331  }
332  if (var)
333  var->last_load_time = av_gettime();
334 
335 fail:
336  if (close_in)
337  avio_close(in);
338  return ret;
339 }
340 
341 static int open_input(HLSContext *c, struct variant *var)
342 {
343  AVDictionary *opts = NULL;
344  int ret;
345  struct segment *seg = var->segments[var->cur_seq_no - var->start_seq_no];
346 
347  // broker prior HTTP options that should be consistent across requests
348  av_dict_set(&opts, "user-agent", c->user_agent, 0);
349  av_dict_set(&opts, "cookies", c->cookies, 0);
350  av_dict_set(&opts, "seekable", "0", 0);
351 
352  if (seg->key_type == KEY_NONE) {
353  ret = ffurl_open(&var->input, seg->url, AVIO_FLAG_READ,
354  &var->parent->interrupt_callback, &opts);
355  goto cleanup;
356  } else if (seg->key_type == KEY_AES_128) {
357  char iv[33], key[33], url[MAX_URL_SIZE];
358  if (strcmp(seg->key, var->key_url)) {
359  URLContext *uc;
360  if (ffurl_open(&uc, seg->key, AVIO_FLAG_READ,
361  &var->parent->interrupt_callback, &opts) == 0) {
362  if (ffurl_read_complete(uc, var->key, sizeof(var->key))
363  != sizeof(var->key)) {
364  av_log(NULL, AV_LOG_ERROR, "Unable to read key file %s\n",
365  seg->key);
366  }
367  ffurl_close(uc);
368  } else {
369  av_log(NULL, AV_LOG_ERROR, "Unable to open key file %s\n",
370  seg->key);
371  }
372  av_strlcpy(var->key_url, seg->key, sizeof(var->key_url));
373  }
374  ff_data_to_hex(iv, seg->iv, sizeof(seg->iv), 0);
375  ff_data_to_hex(key, var->key, sizeof(var->key), 0);
376  iv[32] = key[32] = '\0';
377  if (strstr(seg->url, "://"))
378  snprintf(url, sizeof(url), "crypto+%s", seg->url);
379  else
380  snprintf(url, sizeof(url), "crypto:%s", seg->url);
381  if ((ret = ffurl_alloc(&var->input, url, AVIO_FLAG_READ,
382  &var->parent->interrupt_callback)) < 0)
383  goto cleanup;
384  av_opt_set(var->input->priv_data, "key", key, 0);
385  av_opt_set(var->input->priv_data, "iv", iv, 0);
386  /* Need to repopulate options */
387  av_dict_free(&opts);
388  av_dict_set(&opts, "seekable", "0", 0);
389  if ((ret = ffurl_connect(var->input, &opts)) < 0) {
390  ffurl_close(var->input);
391  var->input = NULL;
392  goto cleanup;
393  }
394  ret = 0;
395  }
396  else
397  ret = AVERROR(ENOSYS);
398 
399 cleanup:
400  av_dict_free(&opts);
401  return ret;
402 }
403 
404 static int read_data(void *opaque, uint8_t *buf, int buf_size)
405 {
406  struct variant *v = opaque;
407  HLSContext *c = v->parent->priv_data;
408  int ret, i;
409 
410 restart:
411  if (!v->input) {
412  /* If this is a live stream and the reload interval has elapsed since
413  * the last playlist reload, reload the variant playlists now. */
414  int64_t reload_interval = v->n_segments > 0 ?
415  v->segments[v->n_segments - 1]->duration :
416  v->target_duration;
417 
418 reload:
419  if (!v->finished &&
420  av_gettime() - v->last_load_time >= reload_interval) {
421  if ((ret = parse_playlist(c, v->url, v, NULL)) < 0)
422  return ret;
423  /* If we need to reload the playlist again below (if
424  * there's still no more segments), switch to a reload
425  * interval of half the target duration. */
426  reload_interval = v->target_duration / 2;
427  }
428  if (v->cur_seq_no < v->start_seq_no) {
429  av_log(NULL, AV_LOG_WARNING,
430  "skipping %d segments ahead, expired from playlists\n",
431  v->start_seq_no - v->cur_seq_no);
432  v->cur_seq_no = v->start_seq_no;
433  }
434  if (v->cur_seq_no >= v->start_seq_no + v->n_segments) {
435  if (v->finished)
436  return AVERROR_EOF;
437  while (av_gettime() - v->last_load_time < reload_interval) {
439  return AVERROR_EXIT;
440  av_usleep(100*1000);
441  }
442  /* Enough time has elapsed since the last reload */
443  goto reload;
444  }
445 
446  ret = open_input(c, v);
447  if (ret < 0)
448  return ret;
449  }
450  ret = ffurl_read(v->input, buf, buf_size);
451  if (ret > 0)
452  return ret;
453  ffurl_close(v->input);
454  v->input = NULL;
455  v->cur_seq_no++;
456 
457  c->end_of_segment = 1;
458  c->cur_seq_no = v->cur_seq_no;
459 
460  if (v->ctx && v->ctx->nb_streams &&
461  v->parent->nb_streams >= v->stream_offset + v->ctx->nb_streams) {
462  v->needed = 0;
463  for (i = v->stream_offset; i < v->stream_offset + v->ctx->nb_streams;
464  i++) {
465  if (v->parent->streams[i]->discard < AVDISCARD_ALL)
466  v->needed = 1;
467  }
468  }
469  if (!v->needed) {
470  av_log(v->parent, AV_LOG_INFO, "No longer receiving variant %d\n",
471  v->index);
472  return AVERROR_EOF;
473  }
474  goto restart;
475 }
476 
478 {
479  URLContext *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb->opaque;
480  HLSContext *c = s->priv_data;
481  int ret = 0, i, j, stream_offset = 0;
482 
483  c->interrupt_callback = &s->interrupt_callback;
484 
485  // if the URL context is good, read important options we must broker later
486  if (u && u->prot->priv_data_class) {
487  // get the previous user agent & set back to null if string size is zero
488  av_freep(&c->user_agent);
489  av_opt_get(u->priv_data, "user-agent", 0, (uint8_t**)&(c->user_agent));
490  if (c->user_agent && !strlen(c->user_agent))
491  av_freep(&c->user_agent);
492 
493  // get the previous cookies & set back to null if string size is zero
494  av_freep(&c->cookies);
495  av_opt_get(u->priv_data, "cookies", 0, (uint8_t**)&(c->cookies));
496  if (c->cookies && !strlen(c->cookies))
497  av_freep(&c->cookies);
498  }
499 
500  if ((ret = parse_playlist(c, s->filename, NULL, s->pb)) < 0)
501  goto fail;
502 
503  if (c->n_variants == 0) {
504  av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
505  ret = AVERROR_EOF;
506  goto fail;
507  }
508  /* If the playlist only contained variants, parse each individual
509  * variant playlist. */
510  if (c->n_variants > 1 || c->variants[0]->n_segments == 0) {
511  for (i = 0; i < c->n_variants; i++) {
512  struct variant *v = c->variants[i];
513  if ((ret = parse_playlist(c, v->url, v, NULL)) < 0)
514  goto fail;
515  }
516  }
517 
518  if (c->variants[0]->n_segments == 0) {
519  av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
520  ret = AVERROR_EOF;
521  goto fail;
522  }
523 
524  /* If this isn't a live stream, calculate the total duration of the
525  * stream. */
526  if (c->variants[0]->finished) {
527  int64_t duration = 0;
528  for (i = 0; i < c->variants[0]->n_segments; i++)
529  duration += c->variants[0]->segments[i]->duration;
530  s->duration = duration;
531  }
532 
533  /* Open the demuxer for each variant */
534  for (i = 0; i < c->n_variants; i++) {
535  struct variant *v = c->variants[i];
536  AVInputFormat *in_fmt = NULL;
537  char bitrate_str[20];
538  AVProgram *program;
539 
540  if (v->n_segments == 0)
541  continue;
542 
543  if (!(v->ctx = avformat_alloc_context())) {
544  ret = AVERROR(ENOMEM);
545  goto fail;
546  }
547 
548  v->index = i;
549  v->needed = 1;
550  v->parent = s;
551 
552  /* If this is a live stream with more than 3 segments, start at the
553  * third last segment. */
554  v->cur_seq_no = v->start_seq_no;
555  if (!v->finished && v->n_segments > 3)
556  v->cur_seq_no = v->start_seq_no + v->n_segments - 3;
557 
560  read_data, NULL, NULL);
561  v->pb.seekable = 0;
562  ret = av_probe_input_buffer(&v->pb, &in_fmt, v->segments[0]->url,
563  NULL, 0, 0);
564  if (ret < 0) {
565  /* Free the ctx - it isn't initialized properly at this point,
566  * so avformat_close_input shouldn't be called. If
567  * avformat_open_input fails below, it frees and zeros the
568  * context, so it doesn't need any special treatment like this. */
569  av_log(s, AV_LOG_ERROR, "Error when loading first segment '%s'\n", v->segments[0]->url);
571  v->ctx = NULL;
572  goto fail;
573  }
574  v->ctx->pb = &v->pb;
576  ret = avformat_open_input(&v->ctx, v->segments[0]->url, in_fmt, NULL);
577  if (ret < 0)
578  goto fail;
579 
581  ret = avformat_find_stream_info(v->ctx, NULL);
582  if (ret < 0)
583  goto fail;
584  snprintf(bitrate_str, sizeof(bitrate_str), "%d", v->bandwidth);
585 
586  program = av_new_program(s, i);
587  if (!program)
588  goto fail;
589  av_dict_set(&program->metadata, "variant_bitrate", bitrate_str, 0);
590 
591  /* Create new AVStreams for each stream in this variant */
592  for (j = 0; j < v->ctx->nb_streams; j++) {
593  AVStream *st = avformat_new_stream(s, NULL);
594  AVStream *ist = v->ctx->streams[j];
595  if (!st) {
596  ret = AVERROR(ENOMEM);
597  goto fail;
598  }
600  st->id = i;
603  if (v->bandwidth)
604  av_dict_set(&st->metadata, "variant_bitrate", bitrate_str,
605  0);
606  }
608  }
609 
610  c->first_packet = 1;
611  c->first_timestamp = AV_NOPTS_VALUE;
612  c->seek_timestamp = AV_NOPTS_VALUE;
613 
614  return 0;
615 fail:
617  return ret;
618 }
619 
620 static int recheck_discard_flags(AVFormatContext *s, int first)
621 {
622  HLSContext *c = s->priv_data;
623  int i, changed = 0;
624 
625  /* Check if any new streams are needed */
626  for (i = 0; i < c->n_variants; i++)
627  c->variants[i]->cur_needed = 0;
628 
629  for (i = 0; i < s->nb_streams; i++) {
630  AVStream *st = s->streams[i];
631  struct variant *var = c->variants[s->streams[i]->id];
632  if (st->discard < AVDISCARD_ALL)
633  var->cur_needed = 1;
634  }
635  for (i = 0; i < c->n_variants; i++) {
636  struct variant *v = c->variants[i];
637  if (v->cur_needed && !v->needed) {
638  v->needed = 1;
639  changed = 1;
640  v->cur_seq_no = c->cur_seq_no;
641  v->pb.eof_reached = 0;
642  av_log(s, AV_LOG_INFO, "Now receiving variant %d\n", i);
643  } else if (first && !v->cur_needed && v->needed) {
644  if (v->input)
645  ffurl_close(v->input);
646  v->input = NULL;
647  v->needed = 0;
648  changed = 1;
649  av_log(s, AV_LOG_INFO, "No longer receiving variant %d\n", i);
650  }
651  }
652  return changed;
653 }
654 
656 {
657  HLSContext *c = s->priv_data;
658  int ret, i, minvariant = -1;
659 
660  if (c->first_packet) {
661  recheck_discard_flags(s, 1);
662  c->first_packet = 0;
663  }
664 
665 start:
666  c->end_of_segment = 0;
667  for (i = 0; i < c->n_variants; i++) {
668  struct variant *var = c->variants[i];
669  /* Make sure we've got one buffered packet from each open variant
670  * stream */
671  if (var->needed && !var->pkt.data) {
672  while (1) {
673  int64_t ts_diff;
674  AVStream *st;
675  ret = av_read_frame(var->ctx, &var->pkt);
676  if (ret < 0) {
677  if (!url_feof(&var->pb) && ret != AVERROR_EOF)
678  return ret;
679  reset_packet(&var->pkt);
680  break;
681  } else {
682  if (c->first_timestamp == AV_NOPTS_VALUE &&
683  var->pkt.dts != AV_NOPTS_VALUE)
685  var->ctx->streams[var->pkt.stream_index]->time_base,
687  }
688 
689  if (c->seek_timestamp == AV_NOPTS_VALUE)
690  break;
691 
692  if (var->pkt.dts == AV_NOPTS_VALUE) {
694  break;
695  }
696 
697  st = var->ctx->streams[var->pkt.stream_index];
698  ts_diff = av_rescale_rnd(var->pkt.dts, AV_TIME_BASE,
699  st->time_base.den, AV_ROUND_DOWN) -
700  c->seek_timestamp;
701  if (ts_diff >= 0 && (c->seek_flags & AVSEEK_FLAG_ANY ||
702  var->pkt.flags & AV_PKT_FLAG_KEY)) {
704  break;
705  }
706  av_free_packet(&var->pkt);
707  reset_packet(&var->pkt);
708  }
709  }
710  /* Check if this stream still is on an earlier segment number, or
711  * has the packet with the lowest dts */
712  if (var->pkt.data) {
713  struct variant *minvar = c->variants[minvariant];
714  if (minvariant < 0 || var->cur_seq_no < minvar->cur_seq_no) {
715  minvariant = i;
716  } else if (var->cur_seq_no == minvar->cur_seq_no) {
717  int64_t dts = var->pkt.dts;
718  int64_t mindts = minvar->pkt.dts;
719  AVStream *st = var->ctx->streams[var->pkt.stream_index];
720  AVStream *minst = minvar->ctx->streams[minvar->pkt.stream_index];
721 
722  if (dts == AV_NOPTS_VALUE) {
723  minvariant = i;
724  } else if (mindts != AV_NOPTS_VALUE) {
725  if (st->start_time != AV_NOPTS_VALUE)
726  dts -= st->start_time;
727  if (minst->start_time != AV_NOPTS_VALUE)
728  mindts -= minst->start_time;
729 
730  if (av_compare_ts(dts, st->time_base,
731  mindts, minst->time_base) < 0)
732  minvariant = i;
733  }
734  }
735  }
736  }
737  if (c->end_of_segment) {
738  if (recheck_discard_flags(s, 0))
739  goto start;
740  }
741  /* If we got a packet, return it */
742  if (minvariant >= 0) {
743  *pkt = c->variants[minvariant]->pkt;
744  pkt->stream_index += c->variants[minvariant]->stream_offset;
745  reset_packet(&c->variants[minvariant]->pkt);
746  return 0;
747  }
748  return AVERROR_EOF;
749 }
750 
752 {
753  HLSContext *c = s->priv_data;
754 
756  return 0;
757 }
758 
759 static int hls_read_seek(AVFormatContext *s, int stream_index,
760  int64_t timestamp, int flags)
761 {
762  HLSContext *c = s->priv_data;
763  int i, j, ret;
764 
765  if ((flags & AVSEEK_FLAG_BYTE) || !c->variants[0]->finished)
766  return AVERROR(ENOSYS);
767 
768  c->seek_flags = flags;
769  c->seek_timestamp = stream_index < 0 ? timestamp :
770  av_rescale_rnd(timestamp, AV_TIME_BASE,
771  s->streams[stream_index]->time_base.den,
772  flags & AVSEEK_FLAG_BACKWARD ?
774  timestamp = av_rescale_rnd(timestamp, AV_TIME_BASE, stream_index >= 0 ?
775  s->streams[stream_index]->time_base.den :
777  AV_ROUND_DOWN : AV_ROUND_UP);
778  if (s->duration < c->seek_timestamp) {
780  return AVERROR(EIO);
781  }
782 
783  ret = AVERROR(EIO);
784  for (i = 0; i < c->n_variants; i++) {
785  /* Reset reading */
786  struct variant *var = c->variants[i];
787  int64_t pos = c->first_timestamp == AV_NOPTS_VALUE ?
788  0 : c->first_timestamp;
789  if (var->input) {
790  ffurl_close(var->input);
791  var->input = NULL;
792  }
793  av_free_packet(&var->pkt);
794  reset_packet(&var->pkt);
795  var->pb.eof_reached = 0;
796  /* Clear any buffered data */
797  var->pb.buf_end = var->pb.buf_ptr = var->pb.buffer;
798  /* Reset the pos, to let the mpegts demuxer know we've seeked. */
799  var->pb.pos = 0;
800 
801  /* Locate the segment that contains the target timestamp */
802  for (j = 0; j < var->n_segments; j++) {
803  if (timestamp >= pos &&
804  timestamp < pos + var->segments[j]->duration) {
805  var->cur_seq_no = var->start_seq_no + j;
806  ret = 0;
807  break;
808  }
809  pos += var->segments[j]->duration;
810  }
811  if (ret)
813  }
814  return ret;
815 }
816 
817 static int hls_probe(AVProbeData *p)
818 {
819  /* Require #EXTM3U at the start, and either one of the ones below
820  * somewhere for a proper match. */
821  if (strncmp(p->buf, "#EXTM3U", 7))
822  return 0;
823  if (strstr(p->buf, "#EXT-X-STREAM-INF:") ||
824  strstr(p->buf, "#EXT-X-TARGETDURATION:") ||
825  strstr(p->buf, "#EXT-X-MEDIA-SEQUENCE:"))
826  return AVPROBE_SCORE_MAX;
827  return 0;
828 }
829 
831  .name = "hls,applehttp",
832  .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),
833  .priv_data_size = sizeof(HLSContext),
839 };