e8767354680acefb85142014534e36f1198c20f8
[libav.git] / libavformat / hls.c
1 /*
2 * Apple HTTP Live Streaming demuxer
3 * Copyright (c) 2010 Martin Storsjo
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; 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 "avformat.h"
34 #include "internal.h"
35 #include <unistd.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 (preferrably 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 {
54 KEY_NONE,
55 KEY_AES_128,
56 };
57
58 struct segment {
59 int duration;
60 char url[MAX_URL_SIZE];
61 char key[MAX_URL_SIZE];
62 enum KeyType key_type;
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;
73 char url[MAX_URL_SIZE];
74 AVIOContext pb;
75 uint8_t* read_buffer;
76 URLContext *input;
77 AVFormatContext *parent;
78 int index;
79 AVFormatContext *ctx;
80 AVPacket pkt;
81 int stream_offset;
82
83 int finished;
84 int target_duration;
85 int start_seq_no;
86 int n_segments;
87 struct segment **segments;
88 int needed, cur_needed;
89 int cur_seq_no;
90 int64_t last_load_time;
91
92 char key_url[MAX_URL_SIZE];
93 uint8_t key[16];
94 };
95
96 typedef struct HLSContext {
97 int n_variants;
98 struct variant **variants;
99 int cur_seq_no;
100 int end_of_segment;
101 int first_packet;
102 int64_t first_timestamp;
103 int64_t seek_timestamp;
104 int seek_flags;
105 AVIOInterruptCB *interrupt_callback;
106 } HLSContext;
107
108 static int read_chomp_line(AVIOContext *s, char *buf, int maxlen)
109 {
110 int len = ff_get_line(s, buf, maxlen);
111 while (len > 0 && isspace(buf[len - 1]))
112 buf[--len] = '\0';
113 return len;
114 }
115
116 static void free_segment_list(struct variant *var)
117 {
118 int i;
119 for (i = 0; i < var->n_segments; i++)
120 av_free(var->segments[i]);
121 av_freep(&var->segments);
122 var->n_segments = 0;
123 }
124
125 static void free_variant_list(HLSContext *c)
126 {
127 int i;
128 for (i = 0; i < c->n_variants; i++) {
129 struct variant *var = c->variants[i];
130 free_segment_list(var);
131 av_free_packet(&var->pkt);
132 av_free(var->pb.buffer);
133 if (var->input)
134 ffurl_close(var->input);
135 if (var->ctx) {
136 var->ctx->pb = NULL;
137 avformat_close_input(&var->ctx);
138 }
139 av_free(var);
140 }
141 av_freep(&c->variants);
142 c->n_variants = 0;
143 }
144
145 /*
146 * Used to reset a statically allocated AVPacket to a clean slate,
147 * containing no data.
148 */
149 static void reset_packet(AVPacket *pkt)
150 {
151 av_init_packet(pkt);
152 pkt->data = NULL;
153 }
154
155 static struct variant *new_variant(HLSContext *c, int bandwidth,
156 const char *url, const char *base)
157 {
158 struct variant *var = av_mallocz(sizeof(struct variant));
159 if (!var)
160 return NULL;
161 reset_packet(&var->pkt);
162 var->bandwidth = bandwidth;
163 ff_make_absolute_url(var->url, sizeof(var->url), base, url);
164 dynarray_add(&c->variants, &c->n_variants, var);
165 return var;
166 }
167
168 struct variant_info {
169 char bandwidth[20];
170 };
171
172 static void handle_variant_args(struct variant_info *info, const char *key,
173 int key_len, char **dest, int *dest_len)
174 {
175 if (!strncmp(key, "BANDWIDTH=", key_len)) {
176 *dest = info->bandwidth;
177 *dest_len = sizeof(info->bandwidth);
178 }
179 }
180
181 struct key_info {
182 char uri[MAX_URL_SIZE];
183 char method[10];
184 char iv[35];
185 };
186
187 static void handle_key_args(struct key_info *info, const char *key,
188 int key_len, char **dest, int *dest_len)
189 {
190 if (!strncmp(key, "METHOD=", key_len)) {
191 *dest = info->method;
192 *dest_len = sizeof(info->method);
193 } else if (!strncmp(key, "URI=", key_len)) {
194 *dest = info->uri;
195 *dest_len = sizeof(info->uri);
196 } else if (!strncmp(key, "IV=", key_len)) {
197 *dest = info->iv;
198 *dest_len = sizeof(info->iv);
199 }
200 }
201
202 static int parse_playlist(HLSContext *c, const char *url,
203 struct variant *var, AVIOContext *in)
204 {
205 int ret = 0, duration = 0, is_segment = 0, is_variant = 0, bandwidth = 0;
206 enum KeyType key_type = KEY_NONE;
207 uint8_t iv[16] = "";
208 int has_iv = 0;
209 char key[MAX_URL_SIZE] = "";
210 char line[1024];
211 const char *ptr;
212 int close_in = 0;
213
214 if (!in) {
215 close_in = 1;
216 if ((ret = avio_open2(&in, url, AVIO_FLAG_READ,
217 c->interrupt_callback, NULL)) < 0)
218 return ret;
219 }
220
221 read_chomp_line(in, line, sizeof(line));
222 if (strcmp(line, "#EXTM3U")) {
223 ret = AVERROR_INVALIDDATA;
224 goto fail;
225 }
226
227 if (var) {
228 free_segment_list(var);
229 var->finished = 0;
230 }
231 while (!in->eof_reached) {
232 read_chomp_line(in, line, sizeof(line));
233 if (av_strstart(line, "#EXT-X-STREAM-INF:", &ptr)) {
234 struct variant_info info = {{0}};
235 is_variant = 1;
236 ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_variant_args,
237 &info);
238 bandwidth = atoi(info.bandwidth);
239 } else if (av_strstart(line, "#EXT-X-KEY:", &ptr)) {
240 struct key_info info = {{0}};
241 ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_key_args,
242 &info);
243 key_type = KEY_NONE;
244 has_iv = 0;
245 if (!strcmp(info.method, "AES-128"))
246 key_type = KEY_AES_128;
247 if (!strncmp(info.iv, "0x", 2) || !strncmp(info.iv, "0X", 2)) {
248 ff_hex_to_data(iv, info.iv + 2);
249 has_iv = 1;
250 }
251 av_strlcpy(key, info.uri, sizeof(key));
252 } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) {
253 if (!var) {
254 var = new_variant(c, 0, url, NULL);
255 if (!var) {
256 ret = AVERROR(ENOMEM);
257 goto fail;
258 }
259 }
260 var->target_duration = atoi(ptr);
261 } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) {
262 if (!var) {
263 var = new_variant(c, 0, url, NULL);
264 if (!var) {
265 ret = AVERROR(ENOMEM);
266 goto fail;
267 }
268 }
269 var->start_seq_no = atoi(ptr);
270 } else if (av_strstart(line, "#EXT-X-ENDLIST", &ptr)) {
271 if (var)
272 var->finished = 1;
273 } else if (av_strstart(line, "#EXTINF:", &ptr)) {
274 is_segment = 1;
275 duration = atoi(ptr);
276 } else if (av_strstart(line, "#", NULL)) {
277 continue;
278 } else if (line[0]) {
279 if (is_variant) {
280 if (!new_variant(c, bandwidth, line, url)) {
281 ret = AVERROR(ENOMEM);
282 goto fail;
283 }
284 is_variant = 0;
285 bandwidth = 0;
286 }
287 if (is_segment) {
288 struct segment *seg;
289 if (!var) {
290 var = new_variant(c, 0, url, NULL);
291 if (!var) {
292 ret = AVERROR(ENOMEM);
293 goto fail;
294 }
295 }
296 seg = av_malloc(sizeof(struct segment));
297 if (!seg) {
298 ret = AVERROR(ENOMEM);
299 goto fail;
300 }
301 seg->duration = duration;
302 seg->key_type = key_type;
303 if (has_iv) {
304 memcpy(seg->iv, iv, sizeof(iv));
305 } else {
306 int seq = var->start_seq_no + var->n_segments;
307 memset(seg->iv, 0, sizeof(seg->iv));
308 AV_WB32(seg->iv + 12, seq);
309 }
310 ff_make_absolute_url(seg->key, sizeof(seg->key), url, key);
311 ff_make_absolute_url(seg->url, sizeof(seg->url), url, line);
312 dynarray_add(&var->segments, &var->n_segments, seg);
313 is_segment = 0;
314 }
315 }
316 }
317 if (var)
318 var->last_load_time = av_gettime();
319
320 fail:
321 if (close_in)
322 avio_close(in);
323 return ret;
324 }
325
326 static int open_input(struct variant *var)
327 {
328 struct segment *seg = var->segments[var->cur_seq_no - var->start_seq_no];
329 if (seg->key_type == KEY_NONE) {
330 return ffurl_open(&var->input, seg->url, AVIO_FLAG_READ,
331 &var->parent->interrupt_callback, NULL);
332 } else if (seg->key_type == KEY_AES_128) {
333 char iv[33], key[33], url[MAX_URL_SIZE];
334 int ret;
335 if (strcmp(seg->key, var->key_url)) {
336 URLContext *uc;
337 if (ffurl_open(&uc, seg->key, AVIO_FLAG_READ,
338 &var->parent->interrupt_callback, NULL) == 0) {
339 if (ffurl_read_complete(uc, var->key, sizeof(var->key))
340 != sizeof(var->key)) {
341 av_log(NULL, AV_LOG_ERROR, "Unable to read key file %s\n",
342 seg->key);
343 }
344 ffurl_close(uc);
345 } else {
346 av_log(NULL, AV_LOG_ERROR, "Unable to open key file %s\n",
347 seg->key);
348 }
349 av_strlcpy(var->key_url, seg->key, sizeof(var->key_url));
350 }
351 ff_data_to_hex(iv, seg->iv, sizeof(seg->iv), 0);
352 ff_data_to_hex(key, var->key, sizeof(var->key), 0);
353 iv[32] = key[32] = '\0';
354 if (strstr(seg->url, "://"))
355 snprintf(url, sizeof(url), "crypto+%s", seg->url);
356 else
357 snprintf(url, sizeof(url), "crypto:%s", seg->url);
358 if ((ret = ffurl_alloc(&var->input, url, AVIO_FLAG_READ,
359 &var->parent->interrupt_callback)) < 0)
360 return ret;
361 av_opt_set(var->input->priv_data, "key", key, 0);
362 av_opt_set(var->input->priv_data, "iv", iv, 0);
363 if ((ret = ffurl_connect(var->input, NULL)) < 0) {
364 ffurl_close(var->input);
365 var->input = NULL;
366 return ret;
367 }
368 return 0;
369 }
370 return AVERROR(ENOSYS);
371 }
372
373 static int read_data(void *opaque, uint8_t *buf, int buf_size)
374 {
375 struct variant *v = opaque;
376 HLSContext *c = v->parent->priv_data;
377 int ret, i;
378
379 restart:
380 if (!v->input) {
381 /* If this is a live stream and the reload interval has elapsed since
382 * the last playlist reload, reload the variant playlists now. */
383 int64_t reload_interval = v->n_segments > 0 ?
384 v->segments[v->n_segments - 1]->duration :
385 v->target_duration;
386 reload_interval *= 1000000;
387
388 reload:
389 if (!v->finished &&
390 av_gettime() - v->last_load_time >= reload_interval) {
391 if ((ret = parse_playlist(c, v->url, v, NULL)) < 0)
392 return ret;
393 /* If we need to reload the playlist again below (if
394 * there's still no more segments), switch to a reload
395 * interval of half the target duration. */
396 reload_interval = v->target_duration * 500000;
397 }
398 if (v->cur_seq_no < v->start_seq_no) {
399 av_log(NULL, AV_LOG_WARNING,
400 "skipping %d segments ahead, expired from playlists\n",
401 v->start_seq_no - v->cur_seq_no);
402 v->cur_seq_no = v->start_seq_no;
403 }
404 if (v->cur_seq_no >= v->start_seq_no + v->n_segments) {
405 if (v->finished)
406 return AVERROR_EOF;
407 while (av_gettime() - v->last_load_time < reload_interval) {
408 if (ff_check_interrupt(c->interrupt_callback))
409 return AVERROR_EXIT;
410 usleep(100*1000);
411 }
412 /* Enough time has elapsed since the last reload */
413 goto reload;
414 }
415
416 ret = open_input(v);
417 if (ret < 0)
418 return ret;
419 }
420 ret = ffurl_read(v->input, buf, buf_size);
421 if (ret > 0)
422 return ret;
423 if (ret < 0 && ret != AVERROR_EOF)
424 return ret;
425 ffurl_close(v->input);
426 v->input = NULL;
427 v->cur_seq_no++;
428
429 c->end_of_segment = 1;
430 c->cur_seq_no = v->cur_seq_no;
431
432 if (v->ctx && v->ctx->nb_streams) {
433 v->needed = 0;
434 for (i = v->stream_offset; i < v->stream_offset + v->ctx->nb_streams;
435 i++) {
436 if (v->parent->streams[i]->discard < AVDISCARD_ALL)
437 v->needed = 1;
438 }
439 }
440 if (!v->needed) {
441 av_log(v->parent, AV_LOG_INFO, "No longer receiving variant %d\n",
442 v->index);
443 return AVERROR_EOF;
444 }
445 goto restart;
446 }
447
448 static int hls_read_header(AVFormatContext *s)
449 {
450 HLSContext *c = s->priv_data;
451 int ret = 0, i, j, stream_offset = 0;
452
453 c->interrupt_callback = &s->interrupt_callback;
454
455 if ((ret = parse_playlist(c, s->filename, NULL, s->pb)) < 0)
456 goto fail;
457
458 if (c->n_variants == 0) {
459 av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
460 ret = AVERROR_EOF;
461 goto fail;
462 }
463 /* If the playlist only contained variants, parse each individual
464 * variant playlist. */
465 if (c->n_variants > 1 || c->variants[0]->n_segments == 0) {
466 for (i = 0; i < c->n_variants; i++) {
467 struct variant *v = c->variants[i];
468 if ((ret = parse_playlist(c, v->url, v, NULL)) < 0)
469 goto fail;
470 }
471 }
472
473 if (c->variants[0]->n_segments == 0) {
474 av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
475 ret = AVERROR_EOF;
476 goto fail;
477 }
478
479 /* If this isn't a live stream, calculate the total duration of the
480 * stream. */
481 if (c->variants[0]->finished) {
482 int64_t duration = 0;
483 for (i = 0; i < c->variants[0]->n_segments; i++)
484 duration += c->variants[0]->segments[i]->duration;
485 s->duration = duration * AV_TIME_BASE;
486 }
487
488 /* Open the demuxer for each variant */
489 for (i = 0; i < c->n_variants; i++) {
490 struct variant *v = c->variants[i];
491 AVInputFormat *in_fmt = NULL;
492 char bitrate_str[20];
493 if (v->n_segments == 0)
494 continue;
495
496 if (!(v->ctx = avformat_alloc_context())) {
497 ret = AVERROR(ENOMEM);
498 goto fail;
499 }
500
501 v->index = i;
502 v->needed = 1;
503 v->parent = s;
504
505 /* If this is a live stream with more than 3 segments, start at the
506 * third last segment. */
507 v->cur_seq_no = v->start_seq_no;
508 if (!v->finished && v->n_segments > 3)
509 v->cur_seq_no = v->start_seq_no + v->n_segments - 3;
510
511 v->read_buffer = av_malloc(INITIAL_BUFFER_SIZE);
512 ffio_init_context(&v->pb, v->read_buffer, INITIAL_BUFFER_SIZE, 0, v,
513 read_data, NULL, NULL);
514 v->pb.seekable = 0;
515 ret = av_probe_input_buffer(&v->pb, &in_fmt, v->segments[0]->url,
516 NULL, 0, 0);
517 if (ret < 0) {
518 /* Free the ctx - it isn't initialized properly at this point,
519 * so avformat_close_input shouldn't be called. If
520 * avformat_open_input fails below, it frees and zeros the
521 * context, so it doesn't need any special treatment like this. */
522 avformat_free_context(v->ctx);
523 v->ctx = NULL;
524 goto fail;
525 }
526 v->ctx->pb = &v->pb;
527 ret = avformat_open_input(&v->ctx, v->segments[0]->url, in_fmt, NULL);
528 if (ret < 0)
529 goto fail;
530 v->stream_offset = stream_offset;
531 snprintf(bitrate_str, sizeof(bitrate_str), "%d", v->bandwidth);
532 /* Create new AVStreams for each stream in this variant */
533 for (j = 0; j < v->ctx->nb_streams; j++) {
534 AVStream *st = avformat_new_stream(s, NULL);
535 if (!st) {
536 ret = AVERROR(ENOMEM);
537 goto fail;
538 }
539 st->id = i;
540 avcodec_copy_context(st->codec, v->ctx->streams[j]->codec);
541 if (v->bandwidth)
542 av_dict_set(&st->metadata, "variant_bitrate", bitrate_str,
543 0);
544 }
545 stream_offset += v->ctx->nb_streams;
546 }
547
548 c->first_packet = 1;
549 c->first_timestamp = AV_NOPTS_VALUE;
550 c->seek_timestamp = AV_NOPTS_VALUE;
551
552 return 0;
553 fail:
554 free_variant_list(c);
555 return ret;
556 }
557
558 static int recheck_discard_flags(AVFormatContext *s, int first)
559 {
560 HLSContext *c = s->priv_data;
561 int i, changed = 0;
562
563 /* Check if any new streams are needed */
564 for (i = 0; i < c->n_variants; i++)
565 c->variants[i]->cur_needed = 0;;
566
567 for (i = 0; i < s->nb_streams; i++) {
568 AVStream *st = s->streams[i];
569 struct variant *var = c->variants[s->streams[i]->id];
570 if (st->discard < AVDISCARD_ALL)
571 var->cur_needed = 1;
572 }
573 for (i = 0; i < c->n_variants; i++) {
574 struct variant *v = c->variants[i];
575 if (v->cur_needed && !v->needed) {
576 v->needed = 1;
577 changed = 1;
578 v->cur_seq_no = c->cur_seq_no;
579 v->pb.eof_reached = 0;
580 av_log(s, AV_LOG_INFO, "Now receiving variant %d\n", i);
581 } else if (first && !v->cur_needed && v->needed) {
582 if (v->input)
583 ffurl_close(v->input);
584 v->input = NULL;
585 v->needed = 0;
586 changed = 1;
587 av_log(s, AV_LOG_INFO, "No longer receiving variant %d\n", i);
588 }
589 }
590 return changed;
591 }
592
593 static int hls_read_packet(AVFormatContext *s, AVPacket *pkt)
594 {
595 HLSContext *c = s->priv_data;
596 int ret, i, minvariant = -1;
597
598 if (c->first_packet) {
599 recheck_discard_flags(s, 1);
600 c->first_packet = 0;
601 }
602
603 start:
604 c->end_of_segment = 0;
605 for (i = 0; i < c->n_variants; i++) {
606 struct variant *var = c->variants[i];
607 /* Make sure we've got one buffered packet from each open variant
608 * stream */
609 if (var->needed && !var->pkt.data) {
610 while (1) {
611 int64_t ts_diff;
612 AVStream *st;
613 ret = av_read_frame(var->ctx, &var->pkt);
614 if (ret < 0) {
615 if (!var->pb.eof_reached)
616 return ret;
617 reset_packet(&var->pkt);
618 break;
619 } else {
620 if (c->first_timestamp == AV_NOPTS_VALUE)
621 c->first_timestamp = var->pkt.dts;
622 }
623
624 if (c->seek_timestamp == AV_NOPTS_VALUE)
625 break;
626
627 if (var->pkt.dts == AV_NOPTS_VALUE) {
628 c->seek_timestamp = AV_NOPTS_VALUE;
629 break;
630 }
631
632 st = var->ctx->streams[var->pkt.stream_index];
633 ts_diff = av_rescale_rnd(var->pkt.dts, AV_TIME_BASE,
634 st->time_base.den, AV_ROUND_DOWN) -
635 c->seek_timestamp;
636 if (ts_diff >= 0 && (c->seek_flags & AVSEEK_FLAG_ANY ||
637 var->pkt.flags & AV_PKT_FLAG_KEY)) {
638 c->seek_timestamp = AV_NOPTS_VALUE;
639 break;
640 }
641 }
642 }
643 /* Check if this stream has the packet with the lowest dts */
644 if (var->pkt.data) {
645 if (minvariant < 0 ||
646 var->pkt.dts < c->variants[minvariant]->pkt.dts)
647 minvariant = i;
648 }
649 }
650 if (c->end_of_segment) {
651 if (recheck_discard_flags(s, 0))
652 goto start;
653 }
654 /* If we got a packet, return it */
655 if (minvariant >= 0) {
656 *pkt = c->variants[minvariant]->pkt;
657 pkt->stream_index += c->variants[minvariant]->stream_offset;
658 reset_packet(&c->variants[minvariant]->pkt);
659 return 0;
660 }
661 return AVERROR_EOF;
662 }
663
664 static int hls_close(AVFormatContext *s)
665 {
666 HLSContext *c = s->priv_data;
667
668 free_variant_list(c);
669 return 0;
670 }
671
672 static int hls_read_seek(AVFormatContext *s, int stream_index,
673 int64_t timestamp, int flags)
674 {
675 HLSContext *c = s->priv_data;
676 int i, j, ret;
677
678 if ((flags & AVSEEK_FLAG_BYTE) || !c->variants[0]->finished)
679 return AVERROR(ENOSYS);
680
681 c->seek_flags = flags;
682 c->seek_timestamp = stream_index < 0 ? timestamp :
683 av_rescale_rnd(timestamp, AV_TIME_BASE,
684 s->streams[stream_index]->time_base.den,
685 flags & AVSEEK_FLAG_BACKWARD ?
686 AV_ROUND_DOWN : AV_ROUND_UP);
687 timestamp = av_rescale_rnd(timestamp, 1, stream_index >= 0 ?
688 s->streams[stream_index]->time_base.den :
689 AV_TIME_BASE, flags & AVSEEK_FLAG_BACKWARD ?
690 AV_ROUND_DOWN : AV_ROUND_UP);
691 if (s->duration < c->seek_timestamp) {
692 c->seek_timestamp = AV_NOPTS_VALUE;
693 return AVERROR(EIO);
694 }
695
696 ret = AVERROR(EIO);
697 for (i = 0; i < c->n_variants; i++) {
698 /* Reset reading */
699 struct variant *var = c->variants[i];
700 int64_t pos = c->first_timestamp == AV_NOPTS_VALUE ? 0 :
701 av_rescale_rnd(c->first_timestamp, 1,
702 stream_index >= 0 ? s->streams[stream_index]->time_base.den : AV_TIME_BASE,
703 flags & AVSEEK_FLAG_BACKWARD ? AV_ROUND_DOWN : AV_ROUND_UP);
704 if (var->input) {
705 ffurl_close(var->input);
706 var->input = NULL;
707 }
708 av_free_packet(&var->pkt);
709 reset_packet(&var->pkt);
710 var->pb.eof_reached = 0;
711 /* Clear any buffered data */
712 var->pb.buf_end = var->pb.buf_ptr = var->pb.buffer;
713 /* Reset the pos, to let the mpegts demuxer know we've seeked. */
714 var->pb.pos = 0;
715
716 /* Locate the segment that contains the target timestamp */
717 for (j = 0; j < var->n_segments; j++) {
718 if (timestamp >= pos &&
719 timestamp < pos + var->segments[j]->duration) {
720 var->cur_seq_no = var->start_seq_no + j;
721 ret = 0;
722 break;
723 }
724 pos += var->segments[j]->duration;
725 }
726 if (ret)
727 c->seek_timestamp = AV_NOPTS_VALUE;
728 }
729 return ret;
730 }
731
732 static int hls_probe(AVProbeData *p)
733 {
734 /* Require #EXTM3U at the start, and either one of the ones below
735 * somewhere for a proper match. */
736 if (strncmp(p->buf, "#EXTM3U", 7))
737 return 0;
738 if (strstr(p->buf, "#EXT-X-STREAM-INF:") ||
739 strstr(p->buf, "#EXT-X-TARGETDURATION:") ||
740 strstr(p->buf, "#EXT-X-MEDIA-SEQUENCE:"))
741 return AVPROBE_SCORE_MAX;
742 return 0;
743 }
744
745 AVInputFormat ff_hls_demuxer = {
746 .name = "hls,applehttp",
747 .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming format"),
748 .priv_data_size = sizeof(HLSContext),
749 .read_probe = hls_probe,
750 .read_header = hls_read_header,
751 .read_packet = hls_read_packet,
752 .read_close = hls_close,
753 .read_seek = hls_read_seek,
754 };