hls: eliminate ffurl_* usage
[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 "libavutil/time.h"
34 #include "avformat.h"
35 #include "internal.h"
36 #include "avio_internal.h"
37
38 #define INITIAL_BUFFER_SIZE 32768
39
40 /*
41 * An apple http stream consists of a playlist with media segment files,
42 * played sequentially. There may be several playlists with the same
43 * video content, in different bandwidth variants, that are played in
44 * parallel (preferably only one bandwidth variant at a time). In this case,
45 * the user supplied the url to a main playlist that only lists the variant
46 * playlists.
47 *
48 * If the main playlist doesn't point at any variants, we still create
49 * one anonymous toplevel variant for this, to maintain the structure.
50 */
51
52 enum KeyType {
53 KEY_NONE,
54 KEY_AES_128,
55 };
56
57 struct segment {
58 int64_t duration;
59 char url[MAX_URL_SIZE];
60 char key[MAX_URL_SIZE];
61 enum KeyType key_type;
62 uint8_t iv[16];
63 };
64
65 /*
66 * Each variant has its own demuxer. If it currently is active,
67 * it has an open AVIOContext too, and potentially an AVPacket
68 * containing the next packet from this stream.
69 */
70 struct variant {
71 int bandwidth;
72 char url[MAX_URL_SIZE];
73 AVIOContext pb;
74 uint8_t* read_buffer;
75 AVIOContext *input;
76 AVFormatContext *parent;
77 int index;
78 AVFormatContext *ctx;
79 AVPacket pkt;
80 int stream_offset;
81
82 int finished;
83 int64_t target_duration;
84 int start_seq_no;
85 int n_segments;
86 struct segment **segments;
87 int needed, cur_needed;
88 int cur_seq_no;
89 int64_t last_load_time;
90
91 char key_url[MAX_URL_SIZE];
92 uint8_t key[16];
93 };
94
95 typedef struct HLSContext {
96 AVFormatContext *ctx;
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 AVDictionary *avio_opts;
107 } HLSContext;
108
109 static int read_chomp_line(AVIOContext *s, char *buf, int maxlen)
110 {
111 int len = ff_get_line(s, buf, maxlen);
112 while (len > 0 && av_isspace(buf[len - 1]))
113 buf[--len] = '\0';
114 return len;
115 }
116
117 static void free_segment_list(struct variant *var)
118 {
119 int i;
120 for (i = 0; i < var->n_segments; i++)
121 av_free(var->segments[i]);
122 av_freep(&var->segments);
123 var->n_segments = 0;
124 }
125
126 static void free_variant_list(HLSContext *c)
127 {
128 int i;
129 for (i = 0; i < c->n_variants; i++) {
130 struct variant *var = c->variants[i];
131 free_segment_list(var);
132 av_packet_unref(&var->pkt);
133 av_free(var->pb.buffer);
134 if (var->input)
135 ff_format_io_close(c->ctx, &var->input);
136 if (var->ctx) {
137 var->ctx->pb = NULL;
138 avformat_close_input(&var->ctx);
139 }
140 av_free(var);
141 }
142 av_freep(&c->variants);
143 c->n_variants = 0;
144 }
145
146 /*
147 * Used to reset a statically allocated AVPacket to a clean slate,
148 * containing no data.
149 */
150 static void reset_packet(AVPacket *pkt)
151 {
152 av_init_packet(pkt);
153 pkt->data = NULL;
154 }
155
156 static struct variant *new_variant(HLSContext *c, int bandwidth,
157 const char *url, const char *base)
158 {
159 struct variant *var = av_mallocz(sizeof(struct variant));
160 if (!var)
161 return NULL;
162 reset_packet(&var->pkt);
163 var->bandwidth = bandwidth;
164 ff_make_absolute_url(var->url, sizeof(var->url), base, url);
165 dynarray_add(&c->variants, &c->n_variants, var);
166 return var;
167 }
168
169 struct variant_info {
170 char bandwidth[20];
171 };
172
173 static void handle_variant_args(struct variant_info *info, const char *key,
174 int key_len, char **dest, int *dest_len)
175 {
176 if (!strncmp(key, "BANDWIDTH=", key_len)) {
177 *dest = info->bandwidth;
178 *dest_len = sizeof(info->bandwidth);
179 }
180 }
181
182 struct key_info {
183 char uri[MAX_URL_SIZE];
184 char method[10];
185 char iv[35];
186 };
187
188 static void handle_key_args(struct key_info *info, const char *key,
189 int key_len, char **dest, int *dest_len)
190 {
191 if (!strncmp(key, "METHOD=", key_len)) {
192 *dest = info->method;
193 *dest_len = sizeof(info->method);
194 } else if (!strncmp(key, "URI=", key_len)) {
195 *dest = info->uri;
196 *dest_len = sizeof(info->uri);
197 } else if (!strncmp(key, "IV=", key_len)) {
198 *dest = info->iv;
199 *dest_len = sizeof(info->iv);
200 }
201 }
202
203 static int open_in(HLSContext *c, AVIOContext **in, const char *url)
204 {
205 AVDictionary *tmp = NULL;
206 int ret;
207
208 av_dict_copy(&tmp, c->avio_opts, 0);
209
210 ret = c->ctx->io_open(c->ctx, in, url, AVIO_FLAG_READ, &tmp);
211
212 av_dict_free(&tmp);
213 return ret;
214 }
215
216 static int open_url(AVFormatContext *s, AVIOContext **pb, const char *url,
217 const AVDictionary *opts)
218 {
219 AVDictionary *tmp = NULL;
220 int ret;
221
222 av_dict_copy(&tmp, opts, 0);
223
224 ret = s->io_open(s, pb, url, AVIO_FLAG_READ, &tmp);
225
226 av_dict_free(&tmp);
227
228 return ret;
229 }
230
231 static int parse_playlist(HLSContext *c, const char *url,
232 struct variant *var, AVIOContext *in)
233 {
234 int ret = 0, is_segment = 0, is_variant = 0, bandwidth = 0;
235 int64_t duration = 0;
236 enum KeyType key_type = KEY_NONE;
237 uint8_t iv[16] = "";
238 int has_iv = 0;
239 char key[MAX_URL_SIZE] = "";
240 char line[1024];
241 const char *ptr;
242 int close_in = 0;
243 uint8_t *new_url = NULL;
244
245 if (!in) {
246 ret = open_in(c, &in, url);
247 if (ret < 0)
248 return ret;
249 close_in = 1;
250 }
251
252 if (av_opt_get(in, "location", AV_OPT_SEARCH_CHILDREN, &new_url) >= 0)
253 url = new_url;
254
255 read_chomp_line(in, line, sizeof(line));
256 if (strcmp(line, "#EXTM3U")) {
257 ret = AVERROR_INVALIDDATA;
258 goto fail;
259 }
260
261 if (var) {
262 free_segment_list(var);
263 var->finished = 0;
264 }
265 while (!in->eof_reached) {
266 read_chomp_line(in, line, sizeof(line));
267 if (av_strstart(line, "#EXT-X-STREAM-INF:", &ptr)) {
268 struct variant_info info = {{0}};
269 is_variant = 1;
270 ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_variant_args,
271 &info);
272 bandwidth = atoi(info.bandwidth);
273 } else if (av_strstart(line, "#EXT-X-KEY:", &ptr)) {
274 struct key_info info = {{0}};
275 ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_key_args,
276 &info);
277 key_type = KEY_NONE;
278 has_iv = 0;
279 if (!strcmp(info.method, "AES-128"))
280 key_type = KEY_AES_128;
281 if (!strncmp(info.iv, "0x", 2) || !strncmp(info.iv, "0X", 2)) {
282 ff_hex_to_data(iv, info.iv + 2);
283 has_iv = 1;
284 }
285 av_strlcpy(key, info.uri, sizeof(key));
286 } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) {
287 if (!var) {
288 var = new_variant(c, 0, url, NULL);
289 if (!var) {
290 ret = AVERROR(ENOMEM);
291 goto fail;
292 }
293 }
294 var->target_duration = atoi(ptr) * AV_TIME_BASE;
295 } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) {
296 if (!var) {
297 var = new_variant(c, 0, url, NULL);
298 if (!var) {
299 ret = AVERROR(ENOMEM);
300 goto fail;
301 }
302 }
303 var->start_seq_no = atoi(ptr);
304 } else if (av_strstart(line, "#EXT-X-ENDLIST", &ptr)) {
305 if (var)
306 var->finished = 1;
307 } else if (av_strstart(line, "#EXTINF:", &ptr)) {
308 is_segment = 1;
309 duration = atof(ptr) * AV_TIME_BASE;
310 } else if (av_strstart(line, "#", NULL)) {
311 continue;
312 } else if (line[0]) {
313 if (is_variant) {
314 if (!new_variant(c, bandwidth, line, url)) {
315 ret = AVERROR(ENOMEM);
316 goto fail;
317 }
318 is_variant = 0;
319 bandwidth = 0;
320 }
321 if (is_segment) {
322 struct segment *seg;
323 if (!var) {
324 var = new_variant(c, 0, url, NULL);
325 if (!var) {
326 ret = AVERROR(ENOMEM);
327 goto fail;
328 }
329 }
330 seg = av_malloc(sizeof(struct segment));
331 if (!seg) {
332 ret = AVERROR(ENOMEM);
333 goto fail;
334 }
335 seg->duration = duration;
336 seg->key_type = key_type;
337 if (has_iv) {
338 memcpy(seg->iv, iv, sizeof(iv));
339 } else {
340 int seq = var->start_seq_no + var->n_segments;
341 memset(seg->iv, 0, sizeof(seg->iv));
342 AV_WB32(seg->iv + 12, seq);
343 }
344 ff_make_absolute_url(seg->key, sizeof(seg->key), url, key);
345 ff_make_absolute_url(seg->url, sizeof(seg->url), url, line);
346 dynarray_add(&var->segments, &var->n_segments, seg);
347 is_segment = 0;
348 }
349 }
350 }
351 if (var)
352 var->last_load_time = av_gettime_relative();
353
354 fail:
355 av_free(new_url);
356 if (close_in)
357 ff_format_io_close(c->ctx, &in);
358 return ret;
359 }
360
361 static int open_input(struct variant *var)
362 {
363 HLSContext *c = var->parent->priv_data;
364 struct segment *seg = var->segments[var->cur_seq_no - var->start_seq_no];
365 if (seg->key_type == KEY_NONE) {
366 return open_url(var->parent, &var->input, seg->url, c->avio_opts);
367 } else if (seg->key_type == KEY_AES_128) {
368 AVDictionary *opts = NULL;
369 char iv[33], key[33], url[MAX_URL_SIZE];
370 int ret;
371 if (strcmp(seg->key, var->key_url)) {
372 AVIOContext *pb;
373 if (open_url(var->parent, &pb, seg->key, c->avio_opts) == 0) {
374 ret = avio_read(pb, var->key, sizeof(var->key));
375 if (ret != sizeof(var->key)) {
376 av_log(NULL, AV_LOG_ERROR, "Unable to read key file %s\n",
377 seg->key);
378 }
379 ff_format_io_close(var->parent, &pb);
380 } else {
381 av_log(NULL, AV_LOG_ERROR, "Unable to open key file %s\n",
382 seg->key);
383 }
384 av_strlcpy(var->key_url, seg->key, sizeof(var->key_url));
385 }
386 ff_data_to_hex(iv, seg->iv, sizeof(seg->iv), 0);
387 ff_data_to_hex(key, var->key, sizeof(var->key), 0);
388 iv[32] = key[32] = '\0';
389 if (strstr(seg->url, "://"))
390 snprintf(url, sizeof(url), "crypto+%s", seg->url);
391 else
392 snprintf(url, sizeof(url), "crypto:%s", seg->url);
393
394 av_dict_copy(&opts, c->avio_opts, 0);
395 av_dict_set(&opts, "key", key, 0);
396 av_dict_set(&opts, "iv", iv, 0);
397
398 ret = open_url(var->parent, &var->input, url, opts);
399 av_dict_free(&opts);
400 return ret;
401 }
402 return AVERROR(ENOSYS);
403 }
404
405 static int read_data(void *opaque, uint8_t *buf, int buf_size)
406 {
407 struct variant *v = opaque;
408 HLSContext *c = v->parent->priv_data;
409 int ret, i;
410
411 restart:
412 if (!v->input) {
413 /* If this is a live stream and the reload interval has elapsed since
414 * the last playlist reload, reload the variant playlists now. */
415 int64_t reload_interval = v->n_segments > 0 ?
416 v->segments[v->n_segments - 1]->duration :
417 v->target_duration;
418
419 reload:
420 if (!v->finished &&
421 av_gettime_relative() - v->last_load_time >= reload_interval) {
422 if ((ret = parse_playlist(c, v->url, v, NULL)) < 0)
423 return ret;
424 /* If we need to reload the playlist again below (if
425 * there's still no more segments), switch to a reload
426 * interval of half the target duration. */
427 reload_interval = v->target_duration / 2;
428 }
429 if (v->cur_seq_no < v->start_seq_no) {
430 av_log(NULL, AV_LOG_WARNING,
431 "skipping %d segments ahead, expired from playlists\n",
432 v->start_seq_no - v->cur_seq_no);
433 v->cur_seq_no = v->start_seq_no;
434 }
435 if (v->cur_seq_no >= v->start_seq_no + v->n_segments) {
436 if (v->finished)
437 return AVERROR_EOF;
438 while (av_gettime_relative() - v->last_load_time < reload_interval) {
439 if (ff_check_interrupt(c->interrupt_callback))
440 return AVERROR_EXIT;
441 av_usleep(100*1000);
442 }
443 /* Enough time has elapsed since the last reload */
444 goto reload;
445 }
446
447 ret = open_input(v);
448 if (ret < 0)
449 return ret;
450 }
451 ret = avio_read(v->input, buf, buf_size);
452 if (ret > 0)
453 return ret;
454 ff_format_io_close(c->ctx, &v->input);
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
477 static int save_avio_options(AVFormatContext *s)
478 {
479 HLSContext *c = s->priv_data;
480 const char *opts[] = { "headers", "user_agent", NULL }, **opt = opts;
481 uint8_t *buf;
482 int ret = 0;
483
484 while (*opt) {
485 if (av_opt_get(s->pb, *opt, AV_OPT_SEARCH_CHILDREN, &buf) >= 0) {
486 ret = av_dict_set(&c->avio_opts, *opt, buf,
487 AV_DICT_DONT_STRDUP_VAL);
488 if (ret < 0)
489 return ret;
490 }
491 opt++;
492 }
493
494 return ret;
495 }
496
497 static int hls_read_header(AVFormatContext *s)
498 {
499 HLSContext *c = s->priv_data;
500 int ret = 0, i, j, stream_offset = 0;
501
502 c->ctx = s;
503 c->interrupt_callback = &s->interrupt_callback;
504
505 if ((ret = parse_playlist(c, s->filename, NULL, s->pb)) < 0)
506 goto fail;
507
508 if ((ret = save_avio_options(s)) < 0)
509 goto fail;
510
511 if (c->n_variants == 0) {
512 av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
513 ret = AVERROR_EOF;
514 goto fail;
515 }
516 /* If the playlist only contained variants, parse each individual
517 * variant playlist. */
518 if (c->n_variants > 1 || c->variants[0]->n_segments == 0) {
519 for (i = 0; i < c->n_variants; i++) {
520 struct variant *v = c->variants[i];
521 if ((ret = parse_playlist(c, v->url, v, NULL)) < 0)
522 goto fail;
523 }
524 }
525
526 if (c->variants[0]->n_segments == 0) {
527 av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
528 ret = AVERROR_EOF;
529 goto fail;
530 }
531
532 /* If this isn't a live stream, calculate the total duration of the
533 * stream. */
534 if (c->variants[0]->finished) {
535 int64_t duration = 0;
536 for (i = 0; i < c->variants[0]->n_segments; i++)
537 duration += c->variants[0]->segments[i]->duration;
538 s->duration = duration;
539 }
540
541 /* Open the demuxer for each variant */
542 for (i = 0; i < c->n_variants; i++) {
543 struct variant *v = c->variants[i];
544 AVInputFormat *in_fmt = NULL;
545 char bitrate_str[20];
546 AVProgram *program;
547
548 if (v->n_segments == 0)
549 continue;
550
551 if (!(v->ctx = avformat_alloc_context())) {
552 ret = AVERROR(ENOMEM);
553 goto fail;
554 }
555
556 v->index = i;
557 v->needed = 1;
558 v->parent = s;
559
560 /* If this is a live stream with more than 3 segments, start at the
561 * third last segment. */
562 v->cur_seq_no = v->start_seq_no;
563 if (!v->finished && v->n_segments > 3)
564 v->cur_seq_no = v->start_seq_no + v->n_segments - 3;
565
566 v->read_buffer = av_malloc(INITIAL_BUFFER_SIZE);
567 ffio_init_context(&v->pb, v->read_buffer, INITIAL_BUFFER_SIZE, 0, v,
568 read_data, NULL, NULL);
569 v->pb.seekable = 0;
570 ret = av_probe_input_buffer(&v->pb, &in_fmt, v->segments[0]->url,
571 NULL, 0, 0);
572 if (ret < 0) {
573 /* Free the ctx - it isn't initialized properly at this point,
574 * so avformat_close_input shouldn't be called. If
575 * avformat_open_input fails below, it frees and zeros the
576 * context, so it doesn't need any special treatment like this. */
577 avformat_free_context(v->ctx);
578 v->ctx = NULL;
579 goto fail;
580 }
581 v->ctx->pb = &v->pb;
582 v->stream_offset = stream_offset;
583 ret = avformat_open_input(&v->ctx, v->segments[0]->url, in_fmt, NULL);
584 if (ret < 0)
585 goto fail;
586
587 v->ctx->ctx_flags &= ~AVFMTCTX_NOHEADER;
588 ret = avformat_find_stream_info(v->ctx, NULL);
589 if (ret < 0)
590 goto fail;
591 snprintf(bitrate_str, sizeof(bitrate_str), "%d", v->bandwidth);
592
593 program = av_new_program(s, i);
594 if (!program)
595 goto fail;
596 av_dict_set(&program->metadata, "variant_bitrate", bitrate_str, 0);
597
598 /* Create new AVStreams for each stream in this variant */
599 for (j = 0; j < v->ctx->nb_streams; j++) {
600 AVStream *st = avformat_new_stream(s, NULL);
601 AVStream *ist = v->ctx->streams[j];
602 if (!st) {
603 ret = AVERROR(ENOMEM);
604 goto fail;
605 }
606 ff_program_add_stream_index(s, i, stream_offset + j);
607 st->id = i;
608 avpriv_set_pts_info(st, ist->pts_wrap_bits, ist->time_base.num, ist->time_base.den);
609 avcodec_copy_context(st->codec, v->ctx->streams[j]->codec);
610 if (v->bandwidth)
611 av_dict_set(&st->metadata, "variant_bitrate", bitrate_str,
612 0);
613 }
614 stream_offset += v->ctx->nb_streams;
615 }
616
617 c->first_packet = 1;
618 c->first_timestamp = AV_NOPTS_VALUE;
619 c->seek_timestamp = AV_NOPTS_VALUE;
620
621 return 0;
622 fail:
623 free_variant_list(c);
624 return ret;
625 }
626
627 static int recheck_discard_flags(AVFormatContext *s, int first)
628 {
629 HLSContext *c = s->priv_data;
630 int i, changed = 0;
631
632 /* Check if any new streams are needed */
633 for (i = 0; i < c->n_variants; i++)
634 c->variants[i]->cur_needed = 0;;
635
636 for (i = 0; i < s->nb_streams; i++) {
637 AVStream *st = s->streams[i];
638 struct variant *var = c->variants[s->streams[i]->id];
639 if (st->discard < AVDISCARD_ALL)
640 var->cur_needed = 1;
641 }
642 for (i = 0; i < c->n_variants; i++) {
643 struct variant *v = c->variants[i];
644 if (v->cur_needed && !v->needed) {
645 v->needed = 1;
646 changed = 1;
647 v->cur_seq_no = c->cur_seq_no;
648 v->pb.eof_reached = 0;
649 av_log(s, AV_LOG_INFO, "Now receiving variant %d\n", i);
650 } else if (first && !v->cur_needed && v->needed) {
651 if (v->input)
652 ff_format_io_close(s, &v->input);
653 v->needed = 0;
654 changed = 1;
655 av_log(s, AV_LOG_INFO, "No longer receiving variant %d\n", i);
656 }
657 }
658 return changed;
659 }
660
661 static int hls_read_packet(AVFormatContext *s, AVPacket *pkt)
662 {
663 HLSContext *c = s->priv_data;
664 int ret, i, minvariant = -1;
665
666 if (c->first_packet) {
667 recheck_discard_flags(s, 1);
668 c->first_packet = 0;
669 }
670
671 start:
672 c->end_of_segment = 0;
673 for (i = 0; i < c->n_variants; i++) {
674 struct variant *var = c->variants[i];
675 /* Make sure we've got one buffered packet from each open variant
676 * stream */
677 if (var->needed && !var->pkt.data) {
678 while (1) {
679 int64_t ts_diff;
680 AVStream *st;
681 ret = av_read_frame(var->ctx, &var->pkt);
682 if (ret < 0) {
683 if (!var->pb.eof_reached)
684 return ret;
685 reset_packet(&var->pkt);
686 break;
687 } else {
688 if (c->first_timestamp == AV_NOPTS_VALUE &&
689 var->pkt.dts != AV_NOPTS_VALUE)
690 c->first_timestamp = av_rescale_q(var->pkt.dts,
691 var->ctx->streams[var->pkt.stream_index]->time_base,
692 AV_TIME_BASE_Q);
693 }
694
695 if (c->seek_timestamp == AV_NOPTS_VALUE)
696 break;
697
698 if (var->pkt.dts == AV_NOPTS_VALUE) {
699 c->seek_timestamp = AV_NOPTS_VALUE;
700 break;
701 }
702
703 st = var->ctx->streams[var->pkt.stream_index];
704 ts_diff = av_rescale_rnd(var->pkt.dts, AV_TIME_BASE,
705 st->time_base.den, AV_ROUND_DOWN) -
706 c->seek_timestamp;
707 if (ts_diff >= 0 && (c->seek_flags & AVSEEK_FLAG_ANY ||
708 var->pkt.flags & AV_PKT_FLAG_KEY)) {
709 c->seek_timestamp = AV_NOPTS_VALUE;
710 break;
711 }
712 av_packet_unref(&var->pkt);
713 reset_packet(&var->pkt);
714 }
715 }
716 /* Check if this stream still is on an earlier segment number, or
717 * has the packet with the lowest dts */
718 if (var->pkt.data) {
719 struct variant *minvar = minvariant < 0 ?
720 NULL : c->variants[minvariant];
721 if (minvariant < 0 || var->cur_seq_no < minvar->cur_seq_no) {
722 minvariant = i;
723 } else if (var->cur_seq_no == minvar->cur_seq_no) {
724 int64_t dts = var->pkt.dts;
725 int64_t mindts = minvar->pkt.dts;
726 AVStream *st = var->ctx->streams[var->pkt.stream_index];
727 AVStream *minst = minvar->ctx->streams[minvar->pkt.stream_index];
728
729 if (dts == AV_NOPTS_VALUE) {
730 minvariant = i;
731 } else if (mindts != AV_NOPTS_VALUE) {
732 if (st->start_time != AV_NOPTS_VALUE)
733 dts -= st->start_time;
734 if (minst->start_time != AV_NOPTS_VALUE)
735 mindts -= minst->start_time;
736
737 if (av_compare_ts(dts, st->time_base,
738 mindts, minst->time_base) < 0)
739 minvariant = i;
740 }
741 }
742 }
743 }
744 if (c->end_of_segment) {
745 if (recheck_discard_flags(s, 0))
746 goto start;
747 }
748 /* If we got a packet, return it */
749 if (minvariant >= 0) {
750 *pkt = c->variants[minvariant]->pkt;
751 pkt->stream_index += c->variants[minvariant]->stream_offset;
752 reset_packet(&c->variants[minvariant]->pkt);
753 return 0;
754 }
755 return AVERROR_EOF;
756 }
757
758 static int hls_close(AVFormatContext *s)
759 {
760 HLSContext *c = s->priv_data;
761
762 free_variant_list(c);
763
764 av_dict_free(&c->avio_opts);
765
766 return 0;
767 }
768
769 static int hls_read_seek(AVFormatContext *s, int stream_index,
770 int64_t timestamp, int flags)
771 {
772 HLSContext *c = s->priv_data;
773 int i, j, ret;
774
775 if ((flags & AVSEEK_FLAG_BYTE) || !c->variants[0]->finished)
776 return AVERROR(ENOSYS);
777
778 c->seek_flags = flags;
779 c->seek_timestamp = stream_index < 0 ? timestamp :
780 av_rescale_rnd(timestamp, AV_TIME_BASE,
781 s->streams[stream_index]->time_base.den,
782 flags & AVSEEK_FLAG_BACKWARD ?
783 AV_ROUND_DOWN : AV_ROUND_UP);
784 timestamp = av_rescale_rnd(timestamp, AV_TIME_BASE, stream_index >= 0 ?
785 s->streams[stream_index]->time_base.den :
786 AV_TIME_BASE, flags & AVSEEK_FLAG_BACKWARD ?
787 AV_ROUND_DOWN : AV_ROUND_UP);
788 if (s->duration < c->seek_timestamp) {
789 c->seek_timestamp = AV_NOPTS_VALUE;
790 return AVERROR(EIO);
791 }
792
793 ret = AVERROR(EIO);
794 for (i = 0; i < c->n_variants; i++) {
795 /* Reset reading */
796 struct variant *var = c->variants[i];
797 int64_t pos = c->first_timestamp == AV_NOPTS_VALUE ?
798 0 : c->first_timestamp;
799 if (var->input)
800 ff_format_io_close(s, &var->input);
801 av_packet_unref(&var->pkt);
802 reset_packet(&var->pkt);
803 var->pb.eof_reached = 0;
804 /* Clear any buffered data */
805 var->pb.buf_end = var->pb.buf_ptr = var->pb.buffer;
806 /* Reset the pos, to let the mpegts demuxer know we've seeked. */
807 var->pb.pos = 0;
808
809 /* Locate the segment that contains the target timestamp */
810 for (j = 0; j < var->n_segments; j++) {
811 if (timestamp >= pos &&
812 timestamp < pos + var->segments[j]->duration) {
813 var->cur_seq_no = var->start_seq_no + j;
814 ret = 0;
815 break;
816 }
817 pos += var->segments[j]->duration;
818 }
819 if (ret)
820 c->seek_timestamp = AV_NOPTS_VALUE;
821 }
822 return ret;
823 }
824
825 static int hls_probe(AVProbeData *p)
826 {
827 /* Require #EXTM3U at the start, and either one of the ones below
828 * somewhere for a proper match. */
829 if (strncmp(p->buf, "#EXTM3U", 7))
830 return 0;
831 if (strstr(p->buf, "#EXT-X-STREAM-INF:") ||
832 strstr(p->buf, "#EXT-X-TARGETDURATION:") ||
833 strstr(p->buf, "#EXT-X-MEDIA-SEQUENCE:"))
834 return AVPROBE_SCORE_MAX;
835 return 0;
836 }
837
838 AVInputFormat ff_hls_demuxer = {
839 .name = "hls,applehttp",
840 .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),
841 .priv_data_size = sizeof(HLSContext),
842 .read_probe = hls_probe,
843 .read_header = hls_read_header,
844 .read_packet = hls_read_packet,
845 .read_close = hls_close,
846 .read_seek = hls_read_seek,
847 };