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 {
63 KEY_NONE,
64 KEY_AES_128,
65 };
66
67 struct segment {
68 int64_t duration;
69 int64_t url_offset;
70 int64_t size;
71 char *url;
72 char *key;
73 enum KeyType key_type;
74 uint8_t iv[16];
75 };
76
77 struct rendition;
78
79 enum PlaylistType {
80 PLS_TYPE_UNSPECIFIED,
81 PLS_TYPE_EVENT,
82 PLS_TYPE_VOD
83 };
84
85 /*
86 * Each playlist has its own demuxer. If it currently is active,
87 * it has an open AVIOContext too, and potentially an AVPacket
88 * containing the next packet from this stream.
89 */
90 struct playlist {
91 char url[MAX_URL_SIZE];
92 AVIOContext pb;
93 uint8_t* read_buffer;
94 URLContext *input;
95 AVFormatContext *parent;
96 int index;
97 AVFormatContext *ctx;
98 AVPacket pkt;
99 int stream_offset;
100
101 int finished;
102 enum PlaylistType type;
103 int64_t target_duration;
104 int start_seq_no;
105 int n_segments;
106 struct segment **segments;
107 int needed, cur_needed;
108 int cur_seq_no;
109 int64_t cur_seg_offset;
110 int64_t last_load_time;
111
112 char key_url[MAX_URL_SIZE];
113 uint8_t key[16];
114
115 /* ID3 timestamp handling (elementary audio streams have ID3 timestamps
116 * (and possibly other ID3 tags) in the beginning of each segment) */
117 int is_id3_timestamped; /* -1: not yet known */
118 int64_t id3_mpegts_timestamp; /* in mpegts tb */
119 int64_t id3_offset; /* in stream original tb */
120 uint8_t* id3_buf; /* temp buffer for id3 parsing */
121 unsigned int id3_buf_size;
122 AVDictionary *id3_initial; /* data from first id3 tag */
123 int id3_found; /* ID3 tag found at some point */
124 int id3_changed; /* ID3 tag data has changed at some point */
125 ID3v2ExtraMeta *id3_deferred_extra; /* stored here until subdemuxer is opened */
126
127 int64_t seek_timestamp;
128 int seek_flags;
129 int seek_stream_index; /* into subdemuxer stream array */
130
131 /* Renditions associated with this playlist, if any.
132 * Alternative rendition playlists have a single rendition associated
133 * with them, and variant main Media Playlists may have
134 * multiple (playlist-less) renditions associated with them. */
135 int n_renditions;
136 struct rendition **renditions;
137 };
138
139 /*
140 * Renditions are e.g. alternative subtitle or audio streams.
141 * The rendition may either be an external playlist or it may be
142 * contained in the main Media Playlist of the variant (in which case
143 * playlist is NULL).
144 */
145 struct rendition {
146 enum AVMediaType type;
147 struct playlist *playlist;
148 char group_id[MAX_FIELD_LEN];
149 char language[MAX_FIELD_LEN];
150 char name[MAX_FIELD_LEN];
151 int disposition;
152 };
153
154 struct variant {
155 int bandwidth;
156
157 /* every variant contains at least the main Media Playlist in index 0 */
158 int n_playlists;
159 struct playlist **playlists;
160
161 char audio_group[MAX_FIELD_LEN];
162 char video_group[MAX_FIELD_LEN];
163 char subtitles_group[MAX_FIELD_LEN];
164 };
165
166 typedef struct HLSContext {
167 int n_variants;
168 struct variant **variants;
169 int n_playlists;
170 struct playlist **playlists;
171 int n_renditions;
172 struct rendition **renditions;
173
174 int cur_seq_no;
175 int first_packet;
176 int64_t first_timestamp;
177 int64_t cur_timestamp;
178 AVIOInterruptCB *interrupt_callback;
179
180 /* type pun fix */
181 union {
182 char *t_char; ///< holds HTTP user agent set as an AVOption to the HTTP protocol context
183 uint8_t *t_uint8_t;
184 } user_agent;
185
186 /* type pun fix */
187 union {
188 char *t_char; ///< holds HTTP cookie values set in either the initial response or as an AVOption to the HTTP protocol context
189 uint8_t *t_uint8_t;
190 } cookies;
191
192 /* type pun fix */
193 union {
194 char *t_char; ///< holds HTTP headers set as an AVOption to the HTTP protocol context
195 uint8_t *t_uint8_t;
196 } headers;
197 } HLSContext;
198
read_chomp_line(AVIOContext * s,char * buf,int maxlen)199 static int read_chomp_line(AVIOContext *s, char *buf, int maxlen)
200 {
201 int len = ff_get_line(s, buf, maxlen);
202 while (len > 0 && av_isspace(buf[len - 1]))
203 buf[--len] = '\0';
204 return len;
205 }
206
free_segment_list(struct playlist * pls)207 static void free_segment_list(struct playlist *pls)
208 {
209 int i;
210 for (i = 0; i < pls->n_segments; i++) {
211 av_free(pls->segments[i]->key);
212 av_free(pls->segments[i]->url);
213 av_free(pls->segments[i]);
214 }
215 av_freep(&pls->segments);
216 pls->n_segments = 0;
217 }
218
free_playlist_list(HLSContext * c)219 static void free_playlist_list(HLSContext *c)
220 {
221 int i;
222 for (i = 0; i < c->n_playlists; i++) {
223 struct playlist *pls = c->playlists[i];
224 free_segment_list(pls);
225 av_freep(&pls->renditions);
226 av_freep(&pls->id3_buf);
227 av_dict_free(&pls->id3_initial);
228 ff_id3v2_free_extra_meta(&pls->id3_deferred_extra);
229 av_free_packet(&pls->pkt);
230 av_free(pls->pb.buffer);
231 if (pls->input)
232 ffurl_close(pls->input);
233 if (pls->ctx) {
234 pls->ctx->pb = NULL;
235 avformat_close_input(&pls->ctx);
236 }
237 av_free(pls);
238 }
239 av_freep(&c->playlists);
240 av_freep(&c->cookies);
241 av_freep(&c->user_agent);
242 c->n_playlists = 0;
243 }
244
free_variant_list(HLSContext * c)245 static void free_variant_list(HLSContext *c)
246 {
247 int i;
248 for (i = 0; i < c->n_variants; i++) {
249 struct variant *var = c->variants[i];
250 av_freep(&var->playlists);
251 av_free(var);
252 }
253 av_freep(&c->variants);
254 c->n_variants = 0;
255 }
256
free_rendition_list(HLSContext * c)257 static void free_rendition_list(HLSContext *c)
258 {
259 int i;
260 for (i = 0; i < c->n_renditions; i++)
261 av_free(c->renditions[i]);
262 av_freep(&c->renditions);
263 c->n_renditions = 0;
264 }
265
266 /*
267 * Used to reset a statically allocated AVPacket to a clean slate,
268 * containing no data.
269 */
reset_packet(AVPacket * pkt)270 static void reset_packet(AVPacket *pkt)
271 {
272 av_init_packet(pkt);
273 pkt->data = NULL;
274 }
275
new_playlist(HLSContext * c,const char * url,const char * base)276 static struct playlist *new_playlist(HLSContext *c, const char *url,
277 const char *base)
278 {
279 struct playlist *pls = av_mallocz(sizeof(struct playlist));
280 if (!pls)
281 return NULL;
282 reset_packet(&pls->pkt);
283 ff_make_absolute_url(pls->url, sizeof(pls->url), base, url);
284 pls->seek_timestamp = AV_NOPTS_VALUE;
285
286 pls->is_id3_timestamped = -1;
287 pls->id3_mpegts_timestamp = AV_NOPTS_VALUE;
288
289 dynarray_add(&c->playlists, &c->n_playlists, pls);
290 return pls;
291 }
292
293 struct variant_info {
294 char bandwidth[20];
295 /* variant group ids: */
296 char audio[MAX_FIELD_LEN];
297 char video[MAX_FIELD_LEN];
298 char subtitles[MAX_FIELD_LEN];
299 };
300
new_variant(HLSContext * c,struct variant_info * info,const char * url,const char * base)301 static struct variant *new_variant(HLSContext *c, struct variant_info *info,
302 const char *url, const char *base)
303 {
304 struct variant *var;
305 struct playlist *pls;
306
307 pls = new_playlist(c, url, base);
308 if (!pls)
309 return NULL;
310
311 var = av_mallocz(sizeof(struct variant));
312 if (!var)
313 return NULL;
314
315 if (info) {
316 var->bandwidth = atoi(info->bandwidth);
317 strcpy(var->audio_group, info->audio);
318 strcpy(var->video_group, info->video);
319 strcpy(var->subtitles_group, info->subtitles);
320 }
321
322 dynarray_add(&c->variants, &c->n_variants, var);
323 dynarray_add(&var->playlists, &var->n_playlists, pls);
324 return var;
325 }
326
handle_variant_args(struct variant_info * info,const char * key,int key_len,char ** dest,int * dest_len)327 static void handle_variant_args(struct variant_info *info, const char *key,
328 int key_len, char **dest, int *dest_len)
329 {
330 if (!strncmp(key, "BANDWIDTH=", key_len)) {
331 *dest = info->bandwidth;
332 *dest_len = sizeof(info->bandwidth);
333 } else if (!strncmp(key, "AUDIO=", key_len)) {
334 *dest = info->audio;
335 *dest_len = sizeof(info->audio);
336 } else if (!strncmp(key, "VIDEO=", key_len)) {
337 *dest = info->video;
338 *dest_len = sizeof(info->video);
339 } else if (!strncmp(key, "SUBTITLES=", key_len)) {
340 *dest = info->subtitles;
341 *dest_len = sizeof(info->subtitles);
342 }
343 }
344
345 struct key_info {
346 char uri[MAX_URL_SIZE];
347 char method[10];
348 char iv[35];
349 };
350
handle_key_args(struct key_info * info,const char * key,int key_len,char ** dest,int * dest_len)351 static void handle_key_args(struct key_info *info, const char *key,
352 int key_len, char **dest, int *dest_len)
353 {
354 if (!strncmp(key, "METHOD=", key_len)) {
355 *dest = info->method;
356 *dest_len = sizeof(info->method);
357 } else if (!strncmp(key, "URI=", key_len)) {
358 *dest = info->uri;
359 *dest_len = sizeof(info->uri);
360 } else if (!strncmp(key, "IV=", key_len)) {
361 *dest = info->iv;
362 *dest_len = sizeof(info->iv);
363 }
364 }
365
366 struct rendition_info {
367 char type[16];
368 char uri[MAX_URL_SIZE];
369 char group_id[MAX_FIELD_LEN];
370 char language[MAX_FIELD_LEN];
371 char assoc_language[MAX_FIELD_LEN];
372 char name[MAX_FIELD_LEN];
373 char defaultr[4];
374 char forced[4];
375 char characteristics[MAX_CHARACTERISTICS_LEN];
376 };
377
new_rendition(HLSContext * c,struct rendition_info * info,const char * url_base)378 static struct rendition *new_rendition(HLSContext *c, struct rendition_info *info,
379 const char *url_base)
380 {
381 struct rendition *rend;
382 enum AVMediaType type = AVMEDIA_TYPE_UNKNOWN;
383 char *characteristic;
384 char *chr_ptr;
385 char *saveptr;
386
387 if (!strcmp(info->type, "AUDIO"))
388 type = AVMEDIA_TYPE_AUDIO;
389 else if (!strcmp(info->type, "VIDEO"))
390 type = AVMEDIA_TYPE_VIDEO;
391 else if (!strcmp(info->type, "SUBTITLES"))
392 type = AVMEDIA_TYPE_SUBTITLE;
393 else if (!strcmp(info->type, "CLOSED-CAPTIONS"))
394 /* CLOSED-CAPTIONS is ignored since we do not support CEA-608 CC in
395 * AVC SEI RBSP anyway */
396 return NULL;
397
398 if (type == AVMEDIA_TYPE_UNKNOWN)
399 return NULL;
400
401 /* URI is mandatory for subtitles as per spec */
402 if (type == AVMEDIA_TYPE_SUBTITLE && !info->uri[0])
403 return NULL;
404
405 /* TODO: handle subtitles (each segment has to parsed separately) */
406 if (type == AVMEDIA_TYPE_SUBTITLE)
407 return NULL;
408
409 rend = av_mallocz(sizeof(struct rendition));
410 if (!rend)
411 return NULL;
412
413 dynarray_add(&c->renditions, &c->n_renditions, rend);
414
415 rend->type = type;
416 strcpy(rend->group_id, info->group_id);
417 strcpy(rend->language, info->language);
418 strcpy(rend->name, info->name);
419
420 /* add the playlist if this is an external rendition */
421 if (info->uri[0]) {
422 rend->playlist = new_playlist(c, info->uri, url_base);
423 if (rend->playlist)
424 dynarray_add(&rend->playlist->renditions,
425 &rend->playlist->n_renditions, rend);
426 }
427
428 if (info->assoc_language[0]) {
429 int langlen = strlen(rend->language);
430 if (langlen < sizeof(rend->language) - 3) {
431 rend->language[langlen] = ',';
432 strncpy(rend->language + langlen + 1, info->assoc_language,
433 sizeof(rend->language) - langlen - 2);
434 }
435 }
436
437 if (!strcmp(info->defaultr, "YES"))
438 rend->disposition |= AV_DISPOSITION_DEFAULT;
439 if (!strcmp(info->forced, "YES"))
440 rend->disposition |= AV_DISPOSITION_FORCED;
441
442 chr_ptr = info->characteristics;
443 while ((characteristic = av_strtok(chr_ptr, ",", &saveptr))) {
444 if (!strcmp(characteristic, "public.accessibility.describes-music-and-sound"))
445 rend->disposition |= AV_DISPOSITION_HEARING_IMPAIRED;
446 else if (!strcmp(characteristic, "public.accessibility.describes-video"))
447 rend->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
448
449 chr_ptr = NULL;
450 }
451
452 return rend;
453 }
454
handle_rendition_args(struct rendition_info * info,const char * key,int key_len,char ** dest,int * dest_len)455 static void handle_rendition_args(struct rendition_info *info, const char *key,
456 int key_len, char **dest, int *dest_len)
457 {
458 if (!strncmp(key, "TYPE=", key_len)) {
459 *dest = info->type;
460 *dest_len = sizeof(info->type);
461 } else if (!strncmp(key, "URI=", key_len)) {
462 *dest = info->uri;
463 *dest_len = sizeof(info->uri);
464 } else if (!strncmp(key, "GROUP-ID=", key_len)) {
465 *dest = info->group_id;
466 *dest_len = sizeof(info->group_id);
467 } else if (!strncmp(key, "LANGUAGE=", key_len)) {
468 *dest = info->language;
469 *dest_len = sizeof(info->language);
470 } else if (!strncmp(key, "ASSOC-LANGUAGE=", key_len)) {
471 *dest = info->assoc_language;
472 *dest_len = sizeof(info->assoc_language);
473 } else if (!strncmp(key, "NAME=", key_len)) {
474 *dest = info->name;
475 *dest_len = sizeof(info->name);
476 } else if (!strncmp(key, "DEFAULT=", key_len)) {
477 *dest = info->defaultr;
478 *dest_len = sizeof(info->defaultr);
479 } else if (!strncmp(key, "FORCED=", key_len)) {
480 *dest = info->forced;
481 *dest_len = sizeof(info->forced);
482 } else if (!strncmp(key, "CHARACTERISTICS=", key_len)) {
483 *dest = info->characteristics;
484 *dest_len = sizeof(info->characteristics);
485 }
486 /*
487 * ignored:
488 * - AUTOSELECT: client may autoselect based on e.g. system language
489 * - INSTREAM-ID: EIA-608 closed caption number ("CC1".."CC4")
490 */
491 }
492
493 /* used by parse_playlist to allocate a new variant+playlist when the
494 * playlist is detected to be a Media Playlist (not Master Playlist)
495 * and we have no parent Master Playlist (parsing of which would have
496 * allocated the variant and playlist already) */
ensure_playlist(HLSContext * c,struct playlist ** pls,const char * url)497 static int ensure_playlist(HLSContext *c, struct playlist **pls, const char *url)
498 {
499 if (*pls)
500 return 0;
501 if (!new_variant(c, NULL, url, NULL))
502 return AVERROR(ENOMEM);
503 *pls = c->playlists[c->n_playlists - 1];
504 return 0;
505 }
506
507 /* pls = NULL => Master Playlist or parentless Media Playlist
508 * pls = !NULL => parented Media Playlist, playlist+variant allocated */
parse_playlist(HLSContext * c,const char * url,struct playlist * pls,AVIOContext * in)509 static int parse_playlist(HLSContext *c, const char *url,
510 struct playlist *pls, AVIOContext *in)
511 {
512 int ret = 0, is_segment = 0, is_variant = 0;
513 int64_t duration = 0;
514 enum KeyType key_type = KEY_NONE;
515 uint8_t iv[16] = "";
516 int has_iv = 0;
517 char key[MAX_URL_SIZE] = "";
518 char line[MAX_URL_SIZE];
519 const char *ptr;
520 int close_in = 0;
521 int64_t seg_offset = 0;
522 int64_t seg_size = -1;
523 uint8_t *new_url = NULL;
524 struct variant_info variant_info;
525 char tmp_str[MAX_URL_SIZE];
526
527 if (!in) {
528 AVDictionary *opts = NULL;
529 close_in = 1;
530 /* Some HLS servers don't like being sent the range header */
531 av_dict_set(&opts, "seekable", "0", 0);
532
533 // broker prior HTTP options that should be consistent across requests
534 av_dict_set(&opts, "user-agent", c->user_agent.t_char, 0);
535 av_dict_set(&opts, "cookies", c->cookies.t_char, 0);
536 av_dict_set(&opts, "headers", c->headers.t_char, 0);
537
538 ret = avio_open2(&in, url, AVIO_FLAG_READ,
539 c->interrupt_callback, &opts);
540 av_dict_free(&opts);
541 if (ret < 0)
542 return ret;
543 }
544
545 if (av_opt_get(in, "location", AV_OPT_SEARCH_CHILDREN, &new_url) >= 0)
546 url = new_url;
547
548 read_chomp_line(in, line, sizeof(line));
549 if (strcmp(line, "#EXTM3U")) {
550 ret = AVERROR_INVALIDDATA;
551 goto fail;
552 }
553
554 if (pls) {
555 free_segment_list(pls);
556 pls->finished = 0;
557 pls->type = PLS_TYPE_UNSPECIFIED;
558 }
559 while (!avio_feof(in)) {
560 read_chomp_line(in, line, sizeof(line));
561 if (av_strstart(line, "#EXT-X-STREAM-INF:", &ptr)) {
562 is_variant = 1;
563 memset(&variant_info, 0, sizeof(variant_info));
564 ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_variant_args,
565 &variant_info);
566 } else if (av_strstart(line, "#EXT-X-KEY:", &ptr)) {
567 struct key_info info = {{0}};
568 ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_key_args,
569 &info);
570 key_type = KEY_NONE;
571 has_iv = 0;
572 if (!strcmp(info.method, "AES-128"))
573 key_type = KEY_AES_128;
574 if (!strncmp(info.iv, "0x", 2) || !strncmp(info.iv, "0X", 2)) {
575 ff_hex_to_data(iv, info.iv + 2);
576 has_iv = 1;
577 }
578 av_strlcpy(key, info.uri, sizeof(key));
579 } else if (av_strstart(line, "#EXT-X-MEDIA:", &ptr)) {
580 struct rendition_info info = {{0}};
581 ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_rendition_args,
582 &info);
583 new_rendition(c, &info, url);
584 } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) {
585 ret = ensure_playlist(c, &pls, url);
586 if (ret < 0)
587 goto fail;
588 pls->target_duration = atoi(ptr) * AV_TIME_BASE;
589 } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) {
590 ret = ensure_playlist(c, &pls, url);
591 if (ret < 0)
592 goto fail;
593 pls->start_seq_no = atoi(ptr);
594 } else if (av_strstart(line, "#EXT-X-PLAYLIST-TYPE:", &ptr)) {
595 ret = ensure_playlist(c, &pls, url);
596 if (ret < 0)
597 goto fail;
598 if (!strcmp(ptr, "EVENT"))
599 pls->type = PLS_TYPE_EVENT;
600 else if (!strcmp(ptr, "VOD"))
601 pls->type = PLS_TYPE_VOD;
602 } else if (av_strstart(line, "#EXT-X-ENDLIST", &ptr)) {
603 if (pls)
604 pls->finished = 1;
605 } else if (av_strstart(line, "#EXTINF:", &ptr)) {
606 is_segment = 1;
607 duration = atof(ptr) * AV_TIME_BASE;
608 } else if (av_strstart(line, "#EXT-X-BYTERANGE:", &ptr)) {
609 seg_size = atoi(ptr);
610 ptr = strchr(ptr, '@');
611 if (ptr)
612 seg_offset = atoi(ptr+1);
613 } else if (av_strstart(line, "#", NULL)) {
614 continue;
615 } else if (line[0]) {
616 if (is_variant) {
617 if (!new_variant(c, &variant_info, line, url)) {
618 ret = AVERROR(ENOMEM);
619 goto fail;
620 }
621 is_variant = 0;
622 }
623 if (is_segment) {
624 struct segment *seg;
625 if (!pls) {
626 if (!new_variant(c, 0, url, NULL)) {
627 ret = AVERROR(ENOMEM);
628 goto fail;
629 }
630 pls = c->playlists[c->n_playlists - 1];
631 }
632 seg = av_malloc(sizeof(struct segment));
633 if (!seg) {
634 ret = AVERROR(ENOMEM);
635 goto fail;
636 }
637 seg->duration = duration;
638 seg->key_type = key_type;
639 if (has_iv) {
640 memcpy(seg->iv, iv, sizeof(iv));
641 } else {
642 int seq = pls->start_seq_no + pls->n_segments;
643 memset(seg->iv, 0, sizeof(seg->iv));
644 AV_WB32(seg->iv + 12, seq);
645 }
646
647 if (key_type != KEY_NONE) {
648 ff_make_absolute_url(tmp_str, sizeof(tmp_str), url, key);
649 seg->key = av_strdup(tmp_str);
650 if (!seg->key) {
651 av_free(seg);
652 ret = AVERROR(ENOMEM);
653 goto fail;
654 }
655 } else {
656 seg->key = NULL;
657 }
658
659 ff_make_absolute_url(tmp_str, sizeof(tmp_str), url, line);
660 seg->url = av_strdup(tmp_str);
661 if (!seg->url) {
662 av_free(seg->key);
663 av_free(seg);
664 ret = AVERROR(ENOMEM);
665 goto fail;
666 }
667
668 dynarray_add(&pls->segments, &pls->n_segments, seg);
669 is_segment = 0;
670
671 seg->size = seg_size;
672 if (seg_size >= 0) {
673 seg->url_offset = seg_offset;
674 seg_offset += seg_size;
675 seg_size = -1;
676 } else {
677 seg->url_offset = 0;
678 seg_offset = 0;
679 }
680 }
681 }
682 }
683 if (pls)
684 pls->last_load_time = av_gettime();
685
686 fail:
687 av_free(new_url);
688 if (close_in)
689 avio_close(in);
690 return ret;
691 }
692
693 enum ReadFromURLMode {
694 READ_NORMAL,
695 READ_COMPLETE,
696 };
697
698 /* read from URLContext, limiting read to current segment */
read_from_url(struct playlist * pls,uint8_t * buf,int buf_size,enum ReadFromURLMode mode)699 static int read_from_url(struct playlist *pls, uint8_t *buf, int buf_size,
700 enum ReadFromURLMode mode)
701 {
702 int ret;
703 struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no];
704
705 /* limit read if the segment was only a part of a file */
706 if (seg->size >= 0)
707 buf_size = FFMIN(buf_size, seg->size - pls->cur_seg_offset);
708
709 if (mode == READ_COMPLETE)
710 ret = ffurl_read_complete(pls->input, buf, buf_size);
711 else
712 ret = ffurl_read(pls->input, buf, buf_size);
713
714 if (ret > 0)
715 pls->cur_seg_offset += ret;
716
717 return ret;
718 }
719
720 /* Parse the raw ID3 data and pass contents to caller */
parse_id3(AVFormatContext * s,AVIOContext * pb,AVDictionary ** metadata,int64_t * dts,ID3v2ExtraMetaAPIC ** apic,ID3v2ExtraMeta ** extra_meta)721 static void parse_id3(AVFormatContext *s, AVIOContext *pb,
722 AVDictionary **metadata, int64_t *dts,
723 ID3v2ExtraMetaAPIC **apic, ID3v2ExtraMeta **extra_meta)
724 {
725 static const char id3_priv_owner_ts[] = "com.apple.streaming.transportStreamTimestamp";
726 ID3v2ExtraMeta *meta;
727
728 ff_id3v2_read_dict(pb, metadata, ID3v2_DEFAULT_MAGIC, extra_meta);
729 for (meta = *extra_meta; meta; meta = meta->next) {
730 if (!strcmp(meta->tag, "PRIV")) {
731 ID3v2ExtraMetaPRIV *priv = meta->data;
732 if (priv->datasize == 8 && !strcmp(priv->owner, id3_priv_owner_ts)) {
733 /* 33-bit MPEG timestamp */
734 int64_t ts = AV_RB64(priv->data);
735 av_log(s, AV_LOG_DEBUG, "HLS ID3 audio timestamp %"PRId64"\n", ts);
736 if ((ts & ~((ULLN(1) << 33) - 1)) == 0)
737 *dts = ts;
738 else
739 av_log(s, AV_LOG_ERROR, "Invalid HLS ID3 audio timestamp %"PRId64"\n", ts);
740 }
741 } else if (!strcmp(meta->tag, "APIC") && apic)
742 *apic = meta->data;
743 }
744 }
745
746 /* Check if the ID3 metadata contents have changed */
id3_has_changed_values(struct playlist * pls,AVDictionary * metadata,ID3v2ExtraMetaAPIC * apic)747 static int id3_has_changed_values(struct playlist *pls, AVDictionary *metadata,
748 ID3v2ExtraMetaAPIC *apic)
749 {
750 AVDictionaryEntry *entry = NULL;
751 AVDictionaryEntry *oldentry;
752 /* check that no keys have changed values */
753 while ((entry = av_dict_get(metadata, "", entry, AV_DICT_IGNORE_SUFFIX))) {
754 oldentry = av_dict_get(pls->id3_initial, entry->key, NULL, AV_DICT_MATCH_CASE);
755 if (!oldentry || strcmp(oldentry->value, entry->value) != 0)
756 return 1;
757 }
758
759 /* check if apic appeared */
760 if (apic && (pls->ctx->nb_streams != 2 || !pls->ctx->streams[1]->attached_pic.data))
761 return 1;
762
763 if (apic) {
764 int size = pls->ctx->streams[1]->attached_pic.size;
765 if (size != apic->buf->size - FF_INPUT_BUFFER_PADDING_SIZE)
766 return 1;
767
768 if (memcmp(apic->buf->data, pls->ctx->streams[1]->attached_pic.data, size) != 0)
769 return 1;
770 }
771
772 return 0;
773 }
774
775 /* Parse ID3 data and handle the found data */
handle_id3(AVIOContext * pb,struct playlist * pls)776 static void handle_id3(AVIOContext *pb, struct playlist *pls)
777 {
778 AVDictionary *metadata = NULL;
779 ID3v2ExtraMetaAPIC *apic = NULL;
780 ID3v2ExtraMeta *extra_meta = NULL;
781 int64_t timestamp = AV_NOPTS_VALUE;
782
783 parse_id3(pls->ctx, pb, &metadata, ×tamp, &apic, &extra_meta);
784
785 if (timestamp != AV_NOPTS_VALUE) {
786 pls->id3_mpegts_timestamp = timestamp;
787 pls->id3_offset = 0;
788 }
789
790 if (!pls->id3_found) {
791 /* initial ID3 tags */
792 av_assert0(!pls->id3_deferred_extra);
793 pls->id3_found = 1;
794
795 /* get picture attachment and set text metadata */
796 if (pls->ctx->nb_streams)
797 ff_id3v2_parse_apic(pls->ctx, &extra_meta);
798 else
799 /* demuxer not yet opened, defer picture attachment */
800 pls->id3_deferred_extra = extra_meta;
801
802 av_dict_copy(&pls->ctx->metadata, metadata, 0);
803 pls->id3_initial = metadata;
804
805 } else {
806 if (!pls->id3_changed && id3_has_changed_values(pls, metadata, apic)) {
807 avpriv_report_missing_feature(pls->ctx, "Changing ID3 metadata in HLS audio elementary stream");
808 pls->id3_changed = 1;
809 }
810 av_dict_free(&metadata);
811 }
812
813 if (!pls->id3_deferred_extra)
814 ff_id3v2_free_extra_meta(&extra_meta);
815 }
816
817 /* Intercept and handle ID3 tags between URLContext and AVIOContext */
intercept_id3(struct playlist * pls,uint8_t * buf,int buf_size,int * len)818 static void intercept_id3(struct playlist *pls, uint8_t *buf,
819 int buf_size, int *len)
820 {
821 /* intercept id3 tags, we do not want to pass them to the raw
822 * demuxer on all segment switches */
823 int bytes;
824 int id3_buf_pos = 0;
825 int fill_buf = 0;
826
827 /* gather all the id3 tags */
828 while (1) {
829 /* see if we can retrieve enough data for ID3 header */
830 if (*len < ID3v2_HEADER_SIZE && buf_size >= ID3v2_HEADER_SIZE) {
831 bytes = read_from_url(pls, buf + *len, ID3v2_HEADER_SIZE - *len, READ_COMPLETE);
832 if (bytes > 0) {
833
834 if (bytes == ID3v2_HEADER_SIZE - *len)
835 /* no EOF yet, so fill the caller buffer again after
836 * we have stripped the ID3 tags */
837 fill_buf = 1;
838
839 *len += bytes;
840
841 } else if (*len <= 0) {
842 /* error/EOF */
843 *len = bytes;
844 fill_buf = 0;
845 }
846 }
847
848 if (*len < ID3v2_HEADER_SIZE)
849 break;
850
851 if (ff_id3v2_match(buf, ID3v2_DEFAULT_MAGIC)) {
852 struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no];
853 int64_t maxsize = seg->size >= 0 ? seg->size : 1024*1024;
854 int taglen = ff_id3v2_tag_len(buf);
855 int tag_got_bytes = FFMIN(taglen, *len);
856 int remaining = taglen - tag_got_bytes;
857
858 if (taglen > maxsize) {
859 av_log(pls->ctx, AV_LOG_ERROR, "Too large HLS ID3 tag (%d > %"PRId64" bytes)\n",
860 taglen, maxsize);
861 break;
862 }
863
864 /*
865 * Copy the id3 tag to our temporary id3 buffer.
866 * We could read a small id3 tag directly without memcpy, but
867 * we would still need to copy the large tags, and handling
868 * both of those cases together with the possibility for multiple
869 * tags would make the handling a bit complex.
870 */
871 pls->id3_buf = av_fast_realloc(pls->id3_buf, &pls->id3_buf_size, id3_buf_pos + taglen);
872 if (!pls->id3_buf)
873 break;
874 memcpy(pls->id3_buf + id3_buf_pos, buf, tag_got_bytes);
875 id3_buf_pos += tag_got_bytes;
876
877 /* strip the intercepted bytes */
878 *len -= tag_got_bytes;
879 memmove(buf, buf + tag_got_bytes, *len);
880 av_log(pls->ctx, AV_LOG_DEBUG, "Stripped %d HLS ID3 bytes\n", tag_got_bytes);
881
882 if (remaining > 0) {
883 /* read the rest of the tag in */
884 if (read_from_url(pls, pls->id3_buf + id3_buf_pos, remaining, READ_COMPLETE) != remaining)
885 break;
886 id3_buf_pos += remaining;
887 av_log(pls->ctx, AV_LOG_DEBUG, "Stripped additional %d HLS ID3 bytes\n", remaining);
888 }
889
890 } else {
891 /* no more ID3 tags */
892 break;
893 }
894 }
895
896 /* re-fill buffer for the caller unless EOF */
897 if (*len >= 0 && (fill_buf || *len == 0)) {
898 bytes = read_from_url(pls, buf + *len, buf_size - *len, READ_NORMAL);
899
900 /* ignore error if we already had some data */
901 if (bytes >= 0)
902 *len += bytes;
903 else if (*len == 0)
904 *len = bytes;
905 }
906
907 if (pls->id3_buf) {
908 /* Now parse all the ID3 tags */
909 AVIOContext id3ioctx;
910 ffio_init_context(&id3ioctx, pls->id3_buf, id3_buf_pos, 0, NULL, NULL, NULL, NULL);
911 handle_id3(&id3ioctx, pls);
912 }
913
914 if (pls->is_id3_timestamped == -1)
915 pls->is_id3_timestamped = (pls->id3_mpegts_timestamp != AV_NOPTS_VALUE);
916 }
917
open_input(HLSContext * c,struct playlist * pls)918 static int open_input(HLSContext *c, struct playlist *pls)
919 {
920 AVDictionary *opts = NULL;
921 AVDictionary *opts2 = NULL;
922 int ret;
923 struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no];
924
925 // broker prior HTTP options that should be consistent across requests
926 av_dict_set(&opts, "user-agent", c->user_agent.t_char, 0);
927 av_dict_set(&opts, "cookies", c->cookies.t_char, 0);
928 av_dict_set(&opts, "headers", c->headers.t_char, 0);
929 av_dict_set(&opts, "seekable", "0", 0);
930
931 // Same opts for key request (ffurl_open mutilates the opts so it cannot be used twice)
932 av_dict_copy(&opts2, opts, 0);
933
934 if (seg->size >= 0) {
935 /* try to restrict the HTTP request to the part we want
936 * (if this is in fact a HTTP request) */
937 av_dict_set_int(&opts, "offset", seg->url_offset, 0);
938 av_dict_set_int(&opts, "end_offset", seg->url_offset + seg->size, 0);
939 }
940
941 av_log(pls->parent, AV_LOG_VERBOSE, "HLS request for url '%s', offset %"PRId64", playlist %d\n",
942 seg->url, seg->url_offset, pls->index);
943
944 if (seg->key_type == KEY_NONE) {
945 ret = ffurl_open(&pls->input, seg->url, AVIO_FLAG_READ,
946 &pls->parent->interrupt_callback, &opts);
947
948 } else if (seg->key_type == KEY_AES_128) {
949 char iv[33], key[33], url[MAX_URL_SIZE];
950 if (strcmp(seg->key, pls->key_url)) {
951 URLContext *uc;
952 if (ffurl_open(&uc, seg->key, AVIO_FLAG_READ,
953 &pls->parent->interrupt_callback, &opts2) == 0) {
954 if (ffurl_read_complete(uc, pls->key, sizeof(pls->key))
955 != sizeof(pls->key)) {
956 av_log(NULL, AV_LOG_ERROR, "Unable to read key file %s\n",
957 seg->key);
958 }
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 }
986 else
987 ret = AVERROR(ENOSYS);
988
989 /* Seek to the requested position. If this was a HTTP request, the offset
990 * should already be where want it to, but this allows e.g. local testing
991 * without a HTTP server. */
992 if (ret == 0 && seg->key_type == KEY_NONE) {
993 int seekret = ffurl_seek(pls->input, seg->url_offset, SEEK_SET);
994 if (seekret < 0) {
995 av_log(pls->parent, AV_LOG_ERROR, "Unable to seek to offset %"PRId64" of HLS segment '%s'\n", seg->url_offset, seg->url);
996 ret = seekret;
997 ffurl_close(pls->input);
998 pls->input = NULL;
999 }
1000 }
1001
1002 cleanup:
1003 av_dict_free(&opts);
1004 av_dict_free(&opts2);
1005 pls->cur_seg_offset = 0;
1006 return ret;
1007 }
1008
default_reload_interval(struct playlist * pls)1009 static int64_t default_reload_interval(struct playlist *pls)
1010 {
1011 return pls->n_segments > 0 ?
1012 pls->segments[pls->n_segments - 1]->duration :
1013 pls->target_duration;
1014 }
1015
read_data(void * opaque,uint8_t * buf,int buf_size)1016 static int read_data(void *opaque, uint8_t *buf, int buf_size)
1017 {
1018 struct playlist *v = opaque;
1019 HLSContext *c = v->parent->priv_data;
1020 int ret, i;
1021 int just_opened = 0;
1022
1023 restart:
1024 if (!v->needed)
1025 return AVERROR_EOF;
1026
1027 if (!v->input) {
1028 int64_t reload_interval;
1029
1030 /* Check that the playlist is still needed before opening a new
1031 * segment. */
1032 if (v->ctx && v->ctx->nb_streams &&
1033 v->parent->nb_streams >= v->stream_offset + v->ctx->nb_streams) {
1034 v->needed = 0;
1035 for (i = v->stream_offset; i < v->stream_offset + v->ctx->nb_streams;
1036 i++) {
1037 if (v->parent->streams[i]->discard < AVDISCARD_ALL)
1038 v->needed = 1;
1039 }
1040 }
1041 if (!v->needed) {
1042 av_log(v->parent, AV_LOG_INFO, "No longer receiving playlist %d\n",
1043 v->index);
1044 return AVERROR_EOF;
1045 }
1046
1047 /* If this is a live stream and the reload interval has elapsed since
1048 * the last playlist reload, reload the playlists now. */
1049 reload_interval = default_reload_interval(v);
1050
1051 reload:
1052 if (!v->finished &&
1053 av_gettime() - v->last_load_time >= reload_interval) {
1054 if ((ret = parse_playlist(c, v->url, v, NULL)) < 0) {
1055 av_log(v->parent, AV_LOG_WARNING, "Failed to reload playlist %d\n",
1056 v->index);
1057 return ret;
1058 }
1059 /* If we need to reload the playlist again below (if
1060 * there's still no more segments), switch to a reload
1061 * interval of half the target duration. */
1062 reload_interval = v->target_duration / 2;
1063 }
1064 if (v->cur_seq_no < v->start_seq_no) {
1065 av_log(NULL, AV_LOG_WARNING,
1066 "skipping %d segments ahead, expired from playlists\n",
1067 v->start_seq_no - v->cur_seq_no);
1068 v->cur_seq_no = v->start_seq_no;
1069 }
1070 if (v->cur_seq_no >= v->start_seq_no + v->n_segments) {
1071 if (v->finished)
1072 return AVERROR_EOF;
1073 while (av_gettime() - v->last_load_time < reload_interval) {
1074 if (ff_check_interrupt(c->interrupt_callback))
1075 return AVERROR_EXIT;
1076 av_usleep(100*1000);
1077 }
1078 /* Enough time has elapsed since the last reload */
1079 goto reload;
1080 }
1081
1082 ret = open_input(c, v);
1083 if (ret < 0) {
1084 av_log(v->parent, AV_LOG_WARNING, "Failed to open segment of playlist %d\n",
1085 v->index);
1086 return ret;
1087 }
1088 just_opened = 1;
1089 }
1090
1091 ret = read_from_url(v, buf, buf_size, READ_NORMAL);
1092 if (ret > 0) {
1093 if (just_opened && v->is_id3_timestamped != 0) {
1094 /* Intercept ID3 tags here, elementary audio streams are required
1095 * to convey timestamps using them in the beginning of each segment. */
1096 intercept_id3(v, buf, buf_size, &ret);
1097 }
1098
1099 return ret;
1100 }
1101 ffurl_close(v->input);
1102 v->input = NULL;
1103 v->cur_seq_no++;
1104
1105 c->cur_seq_no = v->cur_seq_no;
1106
1107 goto restart;
1108 }
1109
playlist_in_multiple_variants(HLSContext * c,struct playlist * pls)1110 static int playlist_in_multiple_variants(HLSContext *c, struct playlist *pls)
1111 {
1112 int variant_count = 0;
1113 int i, j;
1114
1115 for (i = 0; i < c->n_variants && variant_count < 2; i++) {
1116 struct variant *v = c->variants[i];
1117
1118 for (j = 0; j < v->n_playlists; j++) {
1119 if (v->playlists[j] == pls) {
1120 variant_count++;
1121 break;
1122 }
1123 }
1124 }
1125
1126 return variant_count >= 2;
1127 }
1128
add_renditions_to_variant(HLSContext * c,struct variant * var,enum AVMediaType type,const char * group_id)1129 static void add_renditions_to_variant(HLSContext *c, struct variant *var,
1130 enum AVMediaType type, const char *group_id)
1131 {
1132 int i;
1133
1134 for (i = 0; i < c->n_renditions; i++) {
1135 struct rendition *rend = c->renditions[i];
1136
1137 if (rend->type == type && !strcmp(rend->group_id, group_id)) {
1138
1139 if (rend->playlist)
1140 /* rendition is an external playlist
1141 * => add the playlist to the variant */
1142 dynarray_add(&var->playlists, &var->n_playlists, rend->playlist);
1143 else
1144 /* rendition is part of the variant main Media Playlist
1145 * => add the rendition to the main Media Playlist */
1146 dynarray_add(&var->playlists[0]->renditions,
1147 &var->playlists[0]->n_renditions,
1148 rend);
1149 }
1150 }
1151 }
1152
add_metadata_from_renditions(AVFormatContext * s,struct playlist * pls,enum AVMediaType type)1153 static void add_metadata_from_renditions(AVFormatContext *s, struct playlist *pls,
1154 enum AVMediaType type)
1155 {
1156 int rend_idx = 0;
1157 int i;
1158
1159 for (i = 0; i < pls->ctx->nb_streams; i++) {
1160 AVStream *st = s->streams[pls->stream_offset + i];
1161
1162 if (st->codec->codec_type != type)
1163 continue;
1164
1165 for (; rend_idx < pls->n_renditions; rend_idx++) {
1166 struct rendition *rend = pls->renditions[rend_idx];
1167
1168 if (rend->type != type)
1169 continue;
1170
1171 if (rend->language[0])
1172 av_dict_set(&st->metadata, "language", rend->language, 0);
1173 if (rend->name[0])
1174 av_dict_set(&st->metadata, "comment", rend->name, 0);
1175
1176 st->disposition |= rend->disposition;
1177 }
1178 if (rend_idx >=pls->n_renditions)
1179 break;
1180 }
1181 }
1182
1183 /* if timestamp was in valid range: returns 1 and sets seq_no
1184 * if not: returns 0 and sets seq_no to closest segment */
find_timestamp_in_playlist(HLSContext * c,struct playlist * pls,int64_t timestamp,int * seq_no)1185 static int find_timestamp_in_playlist(HLSContext *c, struct playlist *pls,
1186 int64_t timestamp, int *seq_no)
1187 {
1188 int i;
1189 int64_t pos = c->first_timestamp == AV_NOPTS_VALUE ?
1190 0 : c->first_timestamp;
1191
1192 if (timestamp < pos) {
1193 *seq_no = pls->start_seq_no;
1194 return 0;
1195 }
1196
1197 for (i = 0; i < pls->n_segments; i++) {
1198 int64_t diff = pos + pls->segments[i]->duration - timestamp;
1199 if (diff > 0) {
1200 *seq_no = pls->start_seq_no + i;
1201 return 1;
1202 }
1203 pos += pls->segments[i]->duration;
1204 }
1205
1206 *seq_no = pls->start_seq_no + pls->n_segments - 1;
1207
1208 return 0;
1209 }
1210
select_cur_seq_no(HLSContext * c,struct playlist * pls)1211 static int select_cur_seq_no(HLSContext *c, struct playlist *pls)
1212 {
1213 int seq_no;
1214
1215 if (!pls->finished && !c->first_packet &&
1216 av_gettime() - pls->last_load_time >= default_reload_interval(pls))
1217 /* reload the playlist since it was suspended */
1218 parse_playlist(c, pls->url, pls, NULL);
1219
1220 /* If playback is already in progress (we are just selecting a new
1221 * playlist) and this is a complete file, find the matching segment
1222 * by counting durations. */
1223 if (pls->finished && c->cur_timestamp != AV_NOPTS_VALUE) {
1224 find_timestamp_in_playlist(c, pls, c->cur_timestamp, &seq_no);
1225 return seq_no;
1226 }
1227
1228 if (!pls->finished) {
1229 if (!c->first_packet && /* we are doing a segment selection during playback */
1230 c->cur_seq_no >= pls->start_seq_no &&
1231 c->cur_seq_no < pls->start_seq_no + pls->n_segments)
1232 /* While spec 3.4.3 says that we cannot assume anything about the
1233 * content at the same sequence number on different playlists,
1234 * in practice this seems to work and doing it otherwise would
1235 * require us to download a segment to inspect its timestamps. */
1236 return c->cur_seq_no;
1237
1238 /* If this is a live stream with more than 3 segments, start at the
1239 * third last segment. */
1240 if (pls->n_segments > 3)
1241 return pls->start_seq_no + pls->n_segments - 3;
1242 }
1243
1244 /* Otherwise just start on the first segment. */
1245 return pls->start_seq_no;
1246 }
1247
hls_read_header(AVFormatContext * s)1248 static int hls_read_header(AVFormatContext *s)
1249 {
1250 URLContext *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb->opaque;
1251 HLSContext *c = s->priv_data;
1252 int ret = 0, i, j, stream_offset = 0;
1253
1254 c->interrupt_callback = &s->interrupt_callback;
1255
1256 c->first_packet = 1;
1257 c->first_timestamp = AV_NOPTS_VALUE;
1258 c->cur_timestamp = AV_NOPTS_VALUE;
1259
1260 // if the URL context is good, read important options we must broker later
1261 if (u && u->prot->priv_data_class) {
1262 // get the previous user agent & set back to null if string size is zero
1263 av_freep(&c->user_agent);
1264 av_opt_get(u->priv_data, "user-agent", 0, (uint8_t**)&(c->user_agent));
1265 if (c->user_agent.t_char && !strlen(c->user_agent.t_char))
1266 av_freep(&c->user_agent);
1267
1268 // get the previous cookies & set back to null if string size is zero
1269 av_freep(&c->cookies);
1270 av_opt_get(u->priv_data, "cookies", 0, (uint8_t**)&(c->cookies));
1271 if (c->cookies.t_char && !strlen(c->cookies.t_char))
1272 av_freep(&c->cookies);
1273
1274 // get the previous headers & set back to null if string size is zero
1275 av_freep(&c->headers);
1276 av_opt_get(u->priv_data, "headers", 0, (uint8_t**)&(c->headers));
1277 if (c->headers.t_char && !strlen(c->headers.t_char))
1278 av_freep(&c->headers);
1279 }
1280
1281 if ((ret = parse_playlist(c, s->filename, NULL, s->pb)) < 0)
1282 goto fail;
1283
1284 if (c->n_variants == 0) {
1285 av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
1286 ret = AVERROR_EOF;
1287 goto fail;
1288 }
1289 /* If the playlist only contained playlists (Master Playlist),
1290 * parse each individual playlist. */
1291 if (c->n_playlists > 1 || c->playlists[0]->n_segments == 0) {
1292 for (i = 0; i < c->n_playlists; i++) {
1293 struct playlist *pls = c->playlists[i];
1294 if ((ret = parse_playlist(c, pls->url, pls, NULL)) < 0)
1295 goto fail;
1296 }
1297 }
1298
1299 if (c->variants[0]->playlists[0]->n_segments == 0) {
1300 av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
1301 ret = AVERROR_EOF;
1302 goto fail;
1303 }
1304
1305 /* If this isn't a live stream, calculate the total duration of the
1306 * stream. */
1307 if (c->variants[0]->playlists[0]->finished) {
1308 int64_t duration = 0;
1309 for (i = 0; i < c->variants[0]->playlists[0]->n_segments; i++)
1310 duration += c->variants[0]->playlists[0]->segments[i]->duration;
1311 s->duration = duration;
1312 }
1313
1314 /* Associate renditions with variants */
1315 for (i = 0; i < c->n_variants; i++) {
1316 struct variant *var = c->variants[i];
1317
1318 if (var->audio_group[0])
1319 add_renditions_to_variant(c, var, AVMEDIA_TYPE_AUDIO, var->audio_group);
1320 if (var->video_group[0])
1321 add_renditions_to_variant(c, var, AVMEDIA_TYPE_VIDEO, var->video_group);
1322 if (var->subtitles_group[0])
1323 add_renditions_to_variant(c, var, AVMEDIA_TYPE_SUBTITLE, var->subtitles_group);
1324 }
1325
1326 /* Open the demuxer for each playlist */
1327 for (i = 0; i < c->n_playlists; i++) {
1328 struct playlist *pls = c->playlists[i];
1329 AVInputFormat *in_fmt = NULL;
1330
1331 if (pls->n_segments == 0)
1332 continue;
1333
1334 if (!(pls->ctx = avformat_alloc_context())) {
1335 ret = AVERROR(ENOMEM);
1336 goto fail;
1337 }
1338
1339 pls->index = i;
1340 pls->needed = 1;
1341 pls->parent = s;
1342 pls->cur_seq_no = select_cur_seq_no(c, pls);
1343
1344 pls->read_buffer = av_malloc(INITIAL_BUFFER_SIZE);
1345 ffio_init_context(&pls->pb, pls->read_buffer, INITIAL_BUFFER_SIZE, 0, pls,
1346 read_data, NULL, NULL);
1347 pls->pb.seekable = 0;
1348 ret = av_probe_input_buffer(&pls->pb, &in_fmt, pls->segments[0]->url,
1349 NULL, 0, 0);
1350 if (ret < 0) {
1351 /* Free the ctx - it isn't initialized properly at this point,
1352 * so avformat_close_input shouldn't be called. If
1353 * avformat_open_input fails below, it frees and zeros the
1354 * context, so it doesn't need any special treatment like this. */
1355 av_log(s, AV_LOG_ERROR, "Error when loading first segment '%s'\n", pls->segments[0]->url);
1356 avformat_free_context(pls->ctx);
1357 pls->ctx = NULL;
1358 goto fail;
1359 }
1360 pls->ctx->pb = &pls->pb;
1361 pls->stream_offset = stream_offset;
1362 ret = avformat_open_input(&pls->ctx, pls->segments[0]->url, in_fmt, NULL);
1363 if (ret < 0)
1364 goto fail;
1365
1366 if (pls->id3_deferred_extra && pls->ctx->nb_streams == 1) {
1367 ff_id3v2_parse_apic(pls->ctx, &pls->id3_deferred_extra);
1368 avformat_queue_attached_pictures(pls->ctx);
1369 ff_id3v2_free_extra_meta(&pls->id3_deferred_extra);
1370 pls->id3_deferred_extra = NULL;
1371 }
1372
1373 pls->ctx->ctx_flags &= ~AVFMTCTX_NOHEADER;
1374 ret = avformat_find_stream_info(pls->ctx, NULL);
1375 if (ret < 0)
1376 goto fail;
1377
1378 if (pls->is_id3_timestamped == -1)
1379 av_log(s, AV_LOG_WARNING, "No expected HTTP requests have been made\n");
1380
1381 /* Create new AVStreams for each stream in this playlist */
1382 for (j = 0; j < pls->ctx->nb_streams; j++) {
1383 AVStream *st = avformat_new_stream(s, NULL);
1384 AVStream *ist = pls->ctx->streams[j];
1385 if (!st) {
1386 ret = AVERROR(ENOMEM);
1387 goto fail;
1388 }
1389 st->id = i;
1390
1391 avcodec_copy_context(st->codec, pls->ctx->streams[j]->codec);
1392
1393 if (pls->is_id3_timestamped) /* custom timestamps via id3 */
1394 avpriv_set_pts_info(st, 33, 1, MPEG_TIME_BASE);
1395 else
1396 avpriv_set_pts_info(st, ist->pts_wrap_bits, ist->time_base.num, ist->time_base.den);
1397 }
1398
1399 add_metadata_from_renditions(s, pls, AVMEDIA_TYPE_AUDIO);
1400 add_metadata_from_renditions(s, pls, AVMEDIA_TYPE_VIDEO);
1401 add_metadata_from_renditions(s, pls, AVMEDIA_TYPE_SUBTITLE);
1402
1403 stream_offset += pls->ctx->nb_streams;
1404 }
1405
1406 /* Create a program for each variant */
1407 for (i = 0; i < c->n_variants; i++) {
1408 struct variant *v = c->variants[i];
1409 AVProgram *program;
1410
1411 program = av_new_program(s, i);
1412 if (!program)
1413 goto fail;
1414 av_dict_set_int(&program->metadata, "variant_bitrate", v->bandwidth, 0);
1415
1416 for (j = 0; j < v->n_playlists; j++) {
1417 struct playlist *pls = v->playlists[j];
1418 int is_shared = playlist_in_multiple_variants(c, pls);
1419 int k;
1420
1421 for (k = 0; k < pls->ctx->nb_streams; k++) {
1422 struct AVStream *st = s->streams[pls->stream_offset + k];
1423
1424 ff_program_add_stream_index(s, i, pls->stream_offset + k);
1425
1426 /* Set variant_bitrate for streams unique to this variant */
1427 if (!is_shared && v->bandwidth)
1428 av_dict_set_int(&st->metadata, "variant_bitrate", v->bandwidth, 0);
1429 }
1430 }
1431 }
1432
1433 return 0;
1434 fail:
1435 free_playlist_list(c);
1436 free_variant_list(c);
1437 free_rendition_list(c);
1438 return ret;
1439 }
1440
recheck_discard_flags(AVFormatContext * s,int first)1441 static int recheck_discard_flags(AVFormatContext *s, int first)
1442 {
1443 HLSContext *c = s->priv_data;
1444 int i, changed = 0;
1445
1446 /* Check if any new streams are needed */
1447 for (i = 0; i < c->n_playlists; i++)
1448 c->playlists[i]->cur_needed = 0;
1449
1450 for (i = 0; i < s->nb_streams; i++) {
1451 AVStream *st = s->streams[i];
1452 struct playlist *pls = c->playlists[s->streams[i]->id];
1453 if (st->discard < AVDISCARD_ALL)
1454 pls->cur_needed = 1;
1455 }
1456 for (i = 0; i < c->n_playlists; i++) {
1457 struct playlist *pls = c->playlists[i];
1458 if (pls->cur_needed && !pls->needed) {
1459 pls->needed = 1;
1460 changed = 1;
1461 pls->cur_seq_no = select_cur_seq_no(c, pls);
1462 pls->pb.eof_reached = 0;
1463 if (c->cur_timestamp != AV_NOPTS_VALUE) {
1464 /* catch up */
1465 pls->seek_timestamp = c->cur_timestamp;
1466 pls->seek_flags = AVSEEK_FLAG_ANY;
1467 pls->seek_stream_index = -1;
1468 }
1469 av_log(s, AV_LOG_INFO, "Now receiving playlist %d, segment %d\n", i, pls->cur_seq_no);
1470 } else if (first && !pls->cur_needed && pls->needed) {
1471 if (pls->input)
1472 ffurl_close(pls->input);
1473 pls->input = NULL;
1474 pls->needed = 0;
1475 changed = 1;
1476 av_log(s, AV_LOG_INFO, "No longer receiving playlist %d\n", i);
1477 }
1478 }
1479 return changed;
1480 }
1481
fill_timing_for_id3_timestamped_stream(struct playlist * pls)1482 static void fill_timing_for_id3_timestamped_stream(struct playlist *pls)
1483 {
1484 if (pls->id3_offset >= 0) {
1485 pls->pkt.dts = pls->id3_mpegts_timestamp +
1486 av_rescale_q(pls->id3_offset,
1487 pls->ctx->streams[pls->pkt.stream_index]->time_base,
1488 MPEG_TIME_BASE_Q);
1489 if (pls->pkt.duration)
1490 pls->id3_offset += pls->pkt.duration;
1491 else
1492 pls->id3_offset = -1;
1493 } else {
1494 /* there have been packets with unknown duration
1495 * since the last id3 tag, should not normally happen */
1496 pls->pkt.dts = AV_NOPTS_VALUE;
1497 }
1498
1499 if (pls->pkt.duration) {
1500 pls->pkt.duration = av_rescale_q(pls->pkt.duration,
1501 pls->ctx->streams[pls->pkt.stream_index]->time_base,
1502 MPEG_TIME_BASE_Q);
1503 }
1504 pls->pkt.pts = AV_NOPTS_VALUE;
1505 }
1506
get_timebase(struct playlist * pls)1507 static AVRational get_timebase(struct playlist *pls)
1508 {
1509 if (pls->is_id3_timestamped) {
1510 return MPEG_TIME_BASE_Q;
1511 }
1512
1513 return pls->ctx->streams[pls->pkt.stream_index]->time_base;
1514 }
1515
compare_ts_with_wrapdetect(int64_t ts_a,struct playlist * pls_a,int64_t ts_b,struct playlist * pls_b)1516 static int compare_ts_with_wrapdetect(int64_t ts_a, struct playlist *pls_a,
1517 int64_t ts_b, struct playlist *pls_b)
1518 {
1519 int64_t scaled_ts_a = av_rescale_q(ts_a, get_timebase(pls_a), MPEG_TIME_BASE_Q);
1520 int64_t scaled_ts_b = av_rescale_q(ts_b, get_timebase(pls_b), MPEG_TIME_BASE_Q);
1521
1522 return av_compare_mod(scaled_ts_a, scaled_ts_b, LLN(1) << 33);
1523 }
1524
hls_read_packet(AVFormatContext * s,AVPacket * pkt)1525 static int hls_read_packet(AVFormatContext *s, AVPacket *pkt)
1526 {
1527 HLSContext *c = s->priv_data;
1528 int ret, i, minplaylist = -1;
1529
1530 recheck_discard_flags(s, c->first_packet);
1531
1532 for (i = 0; i < c->n_playlists; i++) {
1533 struct playlist *pls = c->playlists[i];
1534 /* Make sure we've got one buffered packet from each open playlist
1535 * stream */
1536 if (pls->needed && !pls->pkt.data) {
1537 while (1) {
1538 int64_t ts_diff;
1539 AVRational tb;
1540 ret = av_read_frame(pls->ctx, &pls->pkt);
1541 if (ret < 0) {
1542 if (!avio_feof(&pls->pb) && ret != AVERROR_EOF)
1543 return ret;
1544 reset_packet(&pls->pkt);
1545 break;
1546 } else {
1547 /* stream_index check prevents matching picture attachments etc. */
1548 if (pls->is_id3_timestamped && pls->pkt.stream_index == 0) {
1549 /* audio elementary streams are id3 timestamped */
1550 fill_timing_for_id3_timestamped_stream(pls);
1551 }
1552
1553 if (c->first_timestamp == AV_NOPTS_VALUE &&
1554 pls->pkt.dts != AV_NOPTS_VALUE) {
1555 c->first_timestamp = av_rescale_q(pls->pkt.dts,
1556 get_timebase(pls), AV_TIME_BASE_Q);
1557 }
1558 }
1559
1560 if (pls->seek_timestamp == AV_NOPTS_VALUE)
1561 break;
1562
1563 if (pls->seek_stream_index < 0 ||
1564 pls->seek_stream_index == pls->pkt.stream_index) {
1565
1566 if (pls->pkt.dts == AV_NOPTS_VALUE) {
1567 pls->seek_timestamp = AV_NOPTS_VALUE;
1568 break;
1569 }
1570
1571 tb = get_timebase(pls);
1572 ts_diff = av_rescale_rnd(pls->pkt.dts, AV_TIME_BASE,
1573 tb.den, AV_ROUND_DOWN) -
1574 pls->seek_timestamp;
1575 if (ts_diff >= 0 && (pls->seek_flags & AVSEEK_FLAG_ANY ||
1576 pls->pkt.flags & AV_PKT_FLAG_KEY)) {
1577 pls->seek_timestamp = AV_NOPTS_VALUE;
1578 break;
1579 }
1580 }
1581 av_free_packet(&pls->pkt);
1582 reset_packet(&pls->pkt);
1583 }
1584 }
1585 /* Check if this stream has the packet with the lowest dts */
1586 if (pls->pkt.data) {
1587 struct playlist *minpls = minplaylist < 0 ?
1588 NULL : c->playlists[minplaylist];
1589 if (minplaylist < 0) {
1590 minplaylist = i;
1591 } else {
1592 int64_t dts = pls->pkt.dts;
1593 int64_t mindts = minpls->pkt.dts;
1594
1595 if (dts == AV_NOPTS_VALUE ||
1596 (mindts != AV_NOPTS_VALUE && compare_ts_with_wrapdetect(dts, pls, mindts, minpls) < 0))
1597 minplaylist = i;
1598 }
1599 }
1600 }
1601
1602 /* If we got a packet, return it */
1603 if (minplaylist >= 0) {
1604 struct playlist *pls = c->playlists[minplaylist];
1605 *pkt = pls->pkt;
1606 pkt->stream_index += pls->stream_offset;
1607 reset_packet(&c->playlists[minplaylist]->pkt);
1608
1609 if (pkt->dts != AV_NOPTS_VALUE) {
1610 c->cur_timestamp = av_rescale_q(pkt->dts,
1611 pls->ctx->streams[pls->pkt.stream_index]->time_base,
1612 AV_TIME_BASE_Q);
1613 }
1614 return 0;
1615 }
1616 return AVERROR_EOF;
1617 }
1618
hls_close(AVFormatContext * s)1619 static int hls_close(AVFormatContext *s)
1620 {
1621 HLSContext *c = s->priv_data;
1622
1623 free_playlist_list(c);
1624 free_variant_list(c);
1625 free_rendition_list(c);
1626 return 0;
1627 }
1628
hls_read_seek(AVFormatContext * s,int stream_index,int64_t timestamp,int flags)1629 static int hls_read_seek(AVFormatContext *s, int stream_index,
1630 int64_t timestamp, int flags)
1631 {
1632 HLSContext *c = s->priv_data;
1633 struct playlist *seek_pls = NULL;
1634 int i, seq_no;
1635 int64_t first_timestamp, seek_timestamp, duration;
1636
1637 if ((flags & AVSEEK_FLAG_BYTE) ||
1638 !(c->variants[0]->playlists[0]->finished || c->variants[0]->playlists[0]->type == PLS_TYPE_EVENT))
1639 return AVERROR(ENOSYS);
1640
1641 first_timestamp = c->first_timestamp == AV_NOPTS_VALUE ?
1642 0 : c->first_timestamp;
1643
1644 seek_timestamp = av_rescale_rnd(timestamp, AV_TIME_BASE,
1645 s->streams[stream_index]->time_base.den,
1646 flags & AVSEEK_FLAG_BACKWARD ?
1647 AV_ROUND_DOWN : AV_ROUND_UP);
1648
1649 duration = s->duration == AV_NOPTS_VALUE ?
1650 0 : s->duration;
1651
1652 if (0 < duration && duration < seek_timestamp - first_timestamp)
1653 return AVERROR(EIO);
1654
1655 /* find the playlist with the specified stream */
1656 for (i = 0; i < c->n_playlists; i++) {
1657 struct playlist *pls = c->playlists[i];
1658 if (stream_index >= pls->stream_offset &&
1659 stream_index - pls->stream_offset < pls->ctx->nb_streams) {
1660 seek_pls = pls;
1661 break;
1662 }
1663 }
1664 /* check if the timestamp is valid for the playlist with the
1665 * specified stream index */
1666 if (!seek_pls || !find_timestamp_in_playlist(c, seek_pls, seek_timestamp, &seq_no))
1667 return AVERROR(EIO);
1668
1669 /* set segment now so we do not need to search again below */
1670 seek_pls->cur_seq_no = seq_no;
1671 seek_pls->seek_stream_index = stream_index - seek_pls->stream_offset;
1672
1673 for (i = 0; i < c->n_playlists; i++) {
1674 /* Reset reading */
1675 struct playlist *pls = c->playlists[i];
1676 if (pls->input) {
1677 ffurl_close(pls->input);
1678 pls->input = NULL;
1679 }
1680 av_free_packet(&pls->pkt);
1681 reset_packet(&pls->pkt);
1682 pls->pb.eof_reached = 0;
1683 /* Clear any buffered data */
1684 pls->pb.buf_end = pls->pb.buf_ptr = pls->pb.buffer;
1685 /* Reset the pos, to let the mpegts demuxer know we've seeked. */
1686 pls->pb.pos = 0;
1687 /* Flush the packet queue of the subdemuxer. */
1688 ff_read_frame_flush(pls->ctx);
1689
1690 pls->seek_timestamp = seek_timestamp;
1691 pls->seek_flags = flags;
1692
1693 if (pls != seek_pls) {
1694 /* set closest segment seq_no for playlists not handled above */
1695 find_timestamp_in_playlist(c, pls, seek_timestamp, &pls->cur_seq_no);
1696 /* seek the playlist to the given position without taking
1697 * keyframes into account since this playlist does not have the
1698 * specified stream where we should look for the keyframes */
1699 pls->seek_stream_index = -1;
1700 pls->seek_flags |= AVSEEK_FLAG_ANY;
1701 }
1702 }
1703
1704 c->cur_timestamp = seek_timestamp;
1705
1706 return 0;
1707 }
1708
hls_probe(AVProbeData * p)1709 static int hls_probe(AVProbeData *p)
1710 {
1711 /* Require #EXTM3U at the start, and either one of the ones below
1712 * somewhere for a proper match. */
1713 if (strncmp(p->buf, "#EXTM3U", 7))
1714 return 0;
1715 if (strstr(p->buf, "#EXT-X-STREAM-INF:") ||
1716 strstr(p->buf, "#EXT-X-TARGETDURATION:") ||
1717 strstr(p->buf, "#EXT-X-MEDIA-SEQUENCE:"))
1718 return AVPROBE_SCORE_MAX;
1719 return 0;
1720 }
1721
1722 AVInputFormat ff_hls_demuxer = {
1723 .name = "hls,applehttp",
1724 .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),
1725 .priv_data_size = sizeof(HLSContext),
1726 .read_probe = hls_probe,
1727 .read_header = hls_read_header,
1728 .read_packet = hls_read_packet,
1729 .read_close = hls_close,
1730 .read_seek = hls_read_seek,
1731 };
1732