/* * Apple HTTP Live Streaming demuxer * Copyright (c) 2010 Martin Storsjo * Copyright (c) 2013 Anssi Hannula * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * Apple HTTP Live Streaming demuxer * http://tools.ietf.org/html/draft-pantos-http-live-streaming */ #include "libavutil/avstring.h" #include "libavutil/intreadwrite.h" #include "libavutil/mathematics.h" #include "libavutil/opt.h" #include "libavutil/dict.h" #include "libavutil/time.h" #include "avformat.h" #include "internal.h" #include "avio_internal.h" #include "url.h" #define INITIAL_BUFFER_SIZE 32768 #define MAX_FIELD_LEN 64 #define MAX_CHARACTERISTICS_LEN 512 /* * An apple http stream consists of a playlist with media segment files, * played sequentially. There may be several playlists with the same * video content, in different bandwidth variants, that are played in * parallel (preferably only one bandwidth variant at a time). In this case, * the user supplied the url to a main playlist that only lists the variant * playlists. * * If the main playlist doesn't point at any variants, we still create * one anonymous toplevel variant for this, to maintain the structure. */ enum KeyType { KEY_NONE, KEY_AES_128, }; struct segment { int64_t duration; int64_t url_offset; int64_t size; char url[MAX_URL_SIZE]; char key[MAX_URL_SIZE]; enum KeyType key_type; uint8_t iv[16]; }; struct rendition; /* * Each playlist has its own demuxer. If it currently is active, * it has an open AVIOContext too, and potentially an AVPacket * containing the next packet from this stream. */ struct playlist { char url[MAX_URL_SIZE]; AVIOContext pb; uint8_t* read_buffer; URLContext *input; AVFormatContext *parent; int index; AVFormatContext *ctx; AVPacket pkt; int stream_offset; int finished; int64_t target_duration; int start_seq_no; int n_segments; struct segment **segments; int needed, cur_needed; int cur_seq_no; int64_t cur_seg_offset; int64_t last_load_time; char key_url[MAX_URL_SIZE]; uint8_t key[16]; /* Renditions associated with this playlist, if any. * Alternative rendition playlists have a single rendition associated * with them, and variant main Media Playlists may have * multiple (playlist-less) renditions associated with them. */ int n_renditions; struct rendition **renditions; }; /* * Renditions are e.g. alternative subtitle or audio streams. * The rendition may either be an external playlist or it may be * contained in the main Media Playlist of the variant (in which case * playlist is NULL). */ struct rendition { enum AVMediaType type; struct playlist *playlist; char group_id[MAX_FIELD_LEN]; char language[MAX_FIELD_LEN]; char name[MAX_FIELD_LEN]; int disposition; }; struct variant { int bandwidth; /* every variant contains at least the main Media Playlist in index 0 */ int n_playlists; struct playlist **playlists; char audio_group[MAX_FIELD_LEN]; char video_group[MAX_FIELD_LEN]; char subtitles_group[MAX_FIELD_LEN]; }; typedef struct HLSContext { int n_variants; struct variant **variants; int n_playlists; struct playlist **playlists; int n_renditions; struct rendition **renditions; int cur_seq_no; int end_of_segment; int first_packet; int64_t first_timestamp; int64_t seek_timestamp; int seek_flags; AVIOInterruptCB *interrupt_callback; char *user_agent; ///< holds HTTP user agent set as an AVOption to the HTTP protocol context char *cookies; ///< holds HTTP cookie values set in either the initial response or as an AVOption to the HTTP protocol context char *headers; ///< holds HTTP headers set as an AVOption to the HTTP protocol context } HLSContext; static int read_chomp_line(AVIOContext *s, char *buf, int maxlen) { int len = ff_get_line(s, buf, maxlen); while (len > 0 && av_isspace(buf[len - 1])) buf[--len] = '\0'; return len; } static void free_segment_list(struct playlist *pls) { int i; for (i = 0; i < pls->n_segments; i++) av_free(pls->segments[i]); av_freep(&pls->segments); pls->n_segments = 0; } static void free_playlist_list(HLSContext *c) { int i; for (i = 0; i < c->n_playlists; i++) { struct playlist *pls = c->playlists[i]; free_segment_list(pls); av_freep(&pls->renditions); av_free_packet(&pls->pkt); av_free(pls->pb.buffer); if (pls->input) ffurl_close(pls->input); if (pls->ctx) { pls->ctx->pb = NULL; avformat_close_input(&pls->ctx); } av_free(pls); } av_freep(&c->playlists); av_freep(&c->cookies); av_freep(&c->user_agent); c->n_playlists = 0; } static void free_variant_list(HLSContext *c) { int i; for (i = 0; i < c->n_variants; i++) { struct variant *var = c->variants[i]; av_freep(&var->playlists); av_free(var); } av_freep(&c->variants); c->n_variants = 0; } static void free_rendition_list(HLSContext *c) { int i; for (i = 0; i < c->n_renditions; i++) av_free(c->renditions[i]); av_freep(&c->renditions); c->n_renditions = 0; } /* * Used to reset a statically allocated AVPacket to a clean slate, * containing no data. */ static void reset_packet(AVPacket *pkt) { av_init_packet(pkt); pkt->data = NULL; } static struct playlist *new_playlist(HLSContext *c, const char *url, const char *base) { struct playlist *pls = av_mallocz(sizeof(struct playlist)); if (!pls) return NULL; reset_packet(&pls->pkt); ff_make_absolute_url(pls->url, sizeof(pls->url), base, url); dynarray_add(&c->playlists, &c->n_playlists, pls); return pls; } struct variant_info { char bandwidth[20]; /* variant group ids: */ char audio[MAX_FIELD_LEN]; char video[MAX_FIELD_LEN]; char subtitles[MAX_FIELD_LEN]; }; static struct variant *new_variant(HLSContext *c, struct variant_info *info, const char *url, const char *base) { struct variant *var; struct playlist *pls; pls = new_playlist(c, url, base); if (!pls) return NULL; var = av_mallocz(sizeof(struct variant)); if (!var) return NULL; if (info) { var->bandwidth = atoi(info->bandwidth); strcpy(var->audio_group, info->audio); strcpy(var->video_group, info->video); strcpy(var->subtitles_group, info->subtitles); } dynarray_add(&c->variants, &c->n_variants, var); dynarray_add(&var->playlists, &var->n_playlists, pls); return var; } static void handle_variant_args(struct variant_info *info, const char *key, int key_len, char **dest, int *dest_len) { if (!strncmp(key, "BANDWIDTH=", key_len)) { *dest = info->bandwidth; *dest_len = sizeof(info->bandwidth); } else if (!strncmp(key, "AUDIO=", key_len)) { *dest = info->audio; *dest_len = sizeof(info->audio); } else if (!strncmp(key, "VIDEO=", key_len)) { *dest = info->video; *dest_len = sizeof(info->video); } else if (!strncmp(key, "SUBTITLES=", key_len)) { *dest = info->subtitles; *dest_len = sizeof(info->subtitles); } } struct key_info { char uri[MAX_URL_SIZE]; char method[10]; char iv[35]; }; static void handle_key_args(struct key_info *info, const char *key, int key_len, char **dest, int *dest_len) { if (!strncmp(key, "METHOD=", key_len)) { *dest = info->method; *dest_len = sizeof(info->method); } else if (!strncmp(key, "URI=", key_len)) { *dest = info->uri; *dest_len = sizeof(info->uri); } else if (!strncmp(key, "IV=", key_len)) { *dest = info->iv; *dest_len = sizeof(info->iv); } } struct rendition_info { char type[16]; char uri[MAX_URL_SIZE]; char group_id[MAX_FIELD_LEN]; char language[MAX_FIELD_LEN]; char assoc_language[MAX_FIELD_LEN]; char name[MAX_FIELD_LEN]; char defaultr[4]; char forced[4]; char characteristics[MAX_CHARACTERISTICS_LEN]; }; static struct rendition *new_rendition(HLSContext *c, struct rendition_info *info, const char *url_base) { struct rendition *rend; enum AVMediaType type = AVMEDIA_TYPE_UNKNOWN; char *characteristic; char *chr_ptr; char *saveptr; if (!strcmp(info->type, "AUDIO")) type = AVMEDIA_TYPE_AUDIO; else if (!strcmp(info->type, "VIDEO")) type = AVMEDIA_TYPE_VIDEO; else if (!strcmp(info->type, "SUBTITLES")) type = AVMEDIA_TYPE_SUBTITLE; else if (!strcmp(info->type, "CLOSED-CAPTIONS")) /* CLOSED-CAPTIONS is ignored since we do not support CEA-608 CC in * AVC SEI RBSP anyway */ return NULL; if (type == AVMEDIA_TYPE_UNKNOWN) return NULL; /* URI is mandatory for subtitles as per spec */ if (type == AVMEDIA_TYPE_SUBTITLE && !info->uri[0]) return NULL; /* TODO: handle subtitles (each segment has to parsed separately) */ if (type == AVMEDIA_TYPE_SUBTITLE) return NULL; rend = av_mallocz(sizeof(struct rendition)); if (!rend) return NULL; dynarray_add(&c->renditions, &c->n_renditions, rend); rend->type = type; strcpy(rend->group_id, info->group_id); strcpy(rend->language, info->language); strcpy(rend->name, info->name); /* add the playlist if this is an external rendition */ if (info->uri[0]) { rend->playlist = new_playlist(c, info->uri, url_base); if (rend->playlist) dynarray_add(&rend->playlist->renditions, &rend->playlist->n_renditions, rend); } if (info->assoc_language[0]) { int langlen = strlen(rend->language); if (langlen < sizeof(rend->language) - 3) { rend->language[langlen] = ','; strncpy(rend->language + langlen + 1, info->assoc_language, sizeof(rend->language) - langlen - 2); } } if (!strcmp(info->defaultr, "YES")) rend->disposition |= AV_DISPOSITION_DEFAULT; if (!strcmp(info->forced, "YES")) rend->disposition |= AV_DISPOSITION_FORCED; chr_ptr = info->characteristics; while ((characteristic = av_strtok(chr_ptr, ",", &saveptr))) { if (!strcmp(characteristic, "public.accessibility.describes-music-and-sound")) rend->disposition |= AV_DISPOSITION_HEARING_IMPAIRED; else if (!strcmp(characteristic, "public.accessibility.describes-video")) rend->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED; chr_ptr = NULL; } return rend; } static void handle_rendition_args(struct rendition_info *info, const char *key, int key_len, char **dest, int *dest_len) { if (!strncmp(key, "TYPE=", key_len)) { *dest = info->type; *dest_len = sizeof(info->type); } else if (!strncmp(key, "URI=", key_len)) { *dest = info->uri; *dest_len = sizeof(info->uri); } else if (!strncmp(key, "GROUP-ID=", key_len)) { *dest = info->group_id; *dest_len = sizeof(info->group_id); } else if (!strncmp(key, "LANGUAGE=", key_len)) { *dest = info->language; *dest_len = sizeof(info->language); } else if (!strncmp(key, "ASSOC-LANGUAGE=", key_len)) { *dest = info->assoc_language; *dest_len = sizeof(info->assoc_language); } else if (!strncmp(key, "NAME=", key_len)) { *dest = info->name; *dest_len = sizeof(info->name); } else if (!strncmp(key, "DEFAULT=", key_len)) { *dest = info->defaultr; *dest_len = sizeof(info->defaultr); } else if (!strncmp(key, "FORCED=", key_len)) { *dest = info->forced; *dest_len = sizeof(info->forced); } else if (!strncmp(key, "CHARACTERISTICS=", key_len)) { *dest = info->characteristics; *dest_len = sizeof(info->characteristics); } /* * ignored: * - AUTOSELECT: client may autoselect based on e.g. system language * - INSTREAM-ID: EIA-608 closed caption number ("CC1".."CC4") */ } static int parse_playlist(HLSContext *c, const char *url, struct playlist *pls, AVIOContext *in) { int ret = 0, is_segment = 0, is_variant = 0; int64_t duration = 0; enum KeyType key_type = KEY_NONE; uint8_t iv[16] = ""; int has_iv = 0; char key[MAX_URL_SIZE] = ""; char line[MAX_URL_SIZE]; const char *ptr; int close_in = 0; int64_t seg_offset = 0; int64_t seg_size = -1; uint8_t *new_url = NULL; struct variant_info variant_info; if (!in) { AVDictionary *opts = NULL; close_in = 1; /* Some HLS servers don't like being sent the range header */ av_dict_set(&opts, "seekable", "0", 0); // broker prior HTTP options that should be consistent across requests av_dict_set(&opts, "user-agent", c->user_agent, 0); av_dict_set(&opts, "cookies", c->cookies, 0); av_dict_set(&opts, "headers", c->headers, 0); ret = avio_open2(&in, url, AVIO_FLAG_READ, c->interrupt_callback, &opts); av_dict_free(&opts); if (ret < 0) return ret; } if (av_opt_get(in, "location", AV_OPT_SEARCH_CHILDREN, &new_url) >= 0) url = new_url; read_chomp_line(in, line, sizeof(line)); if (strcmp(line, "#EXTM3U")) { ret = AVERROR_INVALIDDATA; goto fail; } if (pls) { free_segment_list(pls); pls->finished = 0; } while (!url_feof(in)) { read_chomp_line(in, line, sizeof(line)); if (av_strstart(line, "#EXT-X-STREAM-INF:", &ptr)) { is_variant = 1; memset(&variant_info, 0, sizeof(variant_info)); ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_variant_args, &variant_info); } else if (av_strstart(line, "#EXT-X-KEY:", &ptr)) { struct key_info info = {{0}}; ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_key_args, &info); key_type = KEY_NONE; has_iv = 0; if (!strcmp(info.method, "AES-128")) key_type = KEY_AES_128; if (!strncmp(info.iv, "0x", 2) || !strncmp(info.iv, "0X", 2)) { ff_hex_to_data(iv, info.iv + 2); has_iv = 1; } av_strlcpy(key, info.uri, sizeof(key)); } else if (av_strstart(line, "#EXT-X-MEDIA:", &ptr)) { struct rendition_info info = {{0}}; ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_rendition_args, &info); new_rendition(c, &info, url); } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) { if (!pls) { if (!new_variant(c, NULL, url, NULL)) { ret = AVERROR(ENOMEM); goto fail; } pls = c->playlists[c->n_playlists - 1]; } pls->target_duration = atoi(ptr) * AV_TIME_BASE; } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) { if (!pls) { if (!new_variant(c, NULL, url, NULL)) { ret = AVERROR(ENOMEM); goto fail; } pls = c->playlists[c->n_playlists - 1]; } pls->start_seq_no = atoi(ptr); } else if (av_strstart(line, "#EXT-X-ENDLIST", &ptr)) { if (pls) pls->finished = 1; } else if (av_strstart(line, "#EXTINF:", &ptr)) { is_segment = 1; duration = atof(ptr) * AV_TIME_BASE; } else if (av_strstart(line, "#EXT-X-BYTERANGE:", &ptr)) { seg_size = atoi(ptr); ptr = strchr(ptr, '@'); if (ptr) seg_offset = atoi(ptr+1); } else if (av_strstart(line, "#", NULL)) { continue; } else if (line[0]) { if (is_variant) { if (!new_variant(c, &variant_info, line, url)) { ret = AVERROR(ENOMEM); goto fail; } is_variant = 0; } if (is_segment) { struct segment *seg; if (!pls) { if (!new_variant(c, 0, url, NULL)) { ret = AVERROR(ENOMEM); goto fail; } pls = c->playlists[c->n_playlists - 1]; } seg = av_malloc(sizeof(struct segment)); if (!seg) { ret = AVERROR(ENOMEM); goto fail; } seg->duration = duration; seg->key_type = key_type; if (has_iv) { memcpy(seg->iv, iv, sizeof(iv)); } else { int seq = pls->start_seq_no + pls->n_segments; memset(seg->iv, 0, sizeof(seg->iv)); AV_WB32(seg->iv + 12, seq); } ff_make_absolute_url(seg->key, sizeof(seg->key), url, key); ff_make_absolute_url(seg->url, sizeof(seg->url), url, line); dynarray_add(&pls->segments, &pls->n_segments, seg); is_segment = 0; seg->size = seg_size; if (seg_size >= 0) { seg->url_offset = seg_offset; seg_offset += seg_size; seg_size = -1; } else { seg->url_offset = 0; seg_offset = 0; } } } } if (pls) pls->last_load_time = av_gettime(); fail: av_free(new_url); if (close_in) avio_close(in); return ret; } /* read from URLContext, limiting read to current segment */ static int read_from_url(struct playlist *pls, uint8_t *buf, int buf_size) { int ret; struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no]; /* limit read if the segment was only a part of a file */ if (seg->size >= 0) buf_size = FFMIN(buf_size, seg->size - pls->cur_seg_offset); ret = ffurl_read(pls->input, buf, buf_size); if (ret > 0) pls->cur_seg_offset += ret; return ret; } static int open_input(HLSContext *c, struct playlist *pls) { AVDictionary *opts = NULL; AVDictionary *opts2 = NULL; int ret; struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no]; // broker prior HTTP options that should be consistent across requests av_dict_set(&opts, "user-agent", c->user_agent, 0); av_dict_set(&opts, "cookies", c->cookies, 0); av_dict_set(&opts, "headers", c->headers, 0); av_dict_set(&opts, "seekable", "0", 0); // Same opts for key request (ffurl_open mutilates the opts so it cannot be used twice) av_dict_copy(&opts2, opts, 0); if (seg->size >= 0) { /* try to restrict the HTTP request to the part we want * (if this is in fact a HTTP request) */ char offset[24] = { 0 }; char end_offset[24] = { 0 }; snprintf(offset, sizeof(offset) - 1, "%"PRId64, seg->url_offset); snprintf(end_offset, sizeof(end_offset) - 1, "%"PRId64, seg->url_offset + seg->size); av_dict_set(&opts, "offset", offset, 0); av_dict_set(&opts, "end_offset", end_offset, 0); } av_log(pls->parent, AV_LOG_VERBOSE, "HLS request for url '%s', offset %"PRId64", playlist %d\n", seg->url, seg->url_offset, pls->index); if (seg->key_type == KEY_NONE) { ret = ffurl_open(&pls->input, seg->url, AVIO_FLAG_READ, &pls->parent->interrupt_callback, &opts); } else if (seg->key_type == KEY_AES_128) { char iv[33], key[33], url[MAX_URL_SIZE]; if (strcmp(seg->key, pls->key_url)) { URLContext *uc; if (ffurl_open(&uc, seg->key, AVIO_FLAG_READ, &pls->parent->interrupt_callback, &opts2) == 0) { if (ffurl_read_complete(uc, pls->key, sizeof(pls->key)) != sizeof(pls->key)) { av_log(NULL, AV_LOG_ERROR, "Unable to read key file %s\n", seg->key); } ffurl_close(uc); } else { av_log(NULL, AV_LOG_ERROR, "Unable to open key file %s\n", seg->key); } av_strlcpy(pls->key_url, seg->key, sizeof(pls->key_url)); } ff_data_to_hex(iv, seg->iv, sizeof(seg->iv), 0); ff_data_to_hex(key, pls->key, sizeof(pls->key), 0); iv[32] = key[32] = '\0'; if (strstr(seg->url, "://")) snprintf(url, sizeof(url), "crypto+%s", seg->url); else snprintf(url, sizeof(url), "crypto:%s", seg->url); if ((ret = ffurl_alloc(&pls->input, url, AVIO_FLAG_READ, &pls->parent->interrupt_callback)) < 0) goto cleanup; av_opt_set(pls->input->priv_data, "key", key, 0); av_opt_set(pls->input->priv_data, "iv", iv, 0); if ((ret = ffurl_connect(pls->input, &opts)) < 0) { ffurl_close(pls->input); pls->input = NULL; goto cleanup; } ret = 0; } else ret = AVERROR(ENOSYS); /* Seek to the requested position. If this was a HTTP request, the offset * should already be where want it to, but this allows e.g. local testing * without a HTTP server. */ if (ret == 0) { int seekret = ffurl_seek(pls->input, seg->url_offset, SEEK_SET); if (seekret < 0) { av_log(pls->parent, AV_LOG_ERROR, "Unable to seek to offset %"PRId64" of HLS segment '%s'\n", seg->url_offset, seg->url); ret = seekret; ffurl_close(pls->input); pls->input = NULL; } } cleanup: av_dict_free(&opts); av_dict_free(&opts2); pls->cur_seg_offset = 0; return ret; } static int read_data(void *opaque, uint8_t *buf, int buf_size) { struct playlist *v = opaque; HLSContext *c = v->parent->priv_data; int ret, i; if (!v->needed) return AVERROR_EOF; restart: if (!v->input) { /* If this is a live stream and the reload interval has elapsed since * the last playlist reload, reload the playlists now. */ int64_t reload_interval = v->n_segments > 0 ? v->segments[v->n_segments - 1]->duration : v->target_duration; reload: if (!v->finished && av_gettime() - v->last_load_time >= reload_interval) { if ((ret = parse_playlist(c, v->url, v, NULL)) < 0) { av_log(v->parent, AV_LOG_WARNING, "Failed to reload playlist %d\n", v->index); return ret; } /* If we need to reload the playlist again below (if * there's still no more segments), switch to a reload * interval of half the target duration. */ reload_interval = v->target_duration / 2; } if (v->cur_seq_no < v->start_seq_no) { av_log(NULL, AV_LOG_WARNING, "skipping %d segments ahead, expired from playlists\n", v->start_seq_no - v->cur_seq_no); v->cur_seq_no = v->start_seq_no; } if (v->cur_seq_no >= v->start_seq_no + v->n_segments) { if (v->finished) return AVERROR_EOF; while (av_gettime() - v->last_load_time < reload_interval) { if (ff_check_interrupt(c->interrupt_callback)) return AVERROR_EXIT; av_usleep(100*1000); } /* Enough time has elapsed since the last reload */ goto reload; } ret = open_input(c, v); if (ret < 0) { av_log(v->parent, AV_LOG_WARNING, "Failed to open segment of playlist %d\n", v->index); return ret; } } ret = read_from_url(v, buf, buf_size); if (ret > 0) { return ret; } ffurl_close(v->input); v->input = NULL; v->cur_seq_no++; c->end_of_segment = 1; c->cur_seq_no = v->cur_seq_no; if (v->ctx && v->ctx->nb_streams && v->parent->nb_streams >= v->stream_offset + v->ctx->nb_streams) { v->needed = 0; for (i = v->stream_offset; i < v->stream_offset + v->ctx->nb_streams; i++) { if (v->parent->streams[i]->discard < AVDISCARD_ALL) v->needed = 1; } } if (!v->needed) { av_log(v->parent, AV_LOG_INFO, "No longer receiving playlist %d\n", v->index); return AVERROR_EOF; } goto restart; } static int playlist_in_multiple_variants(HLSContext *c, struct playlist *pls) { int variant_count = 0; int i, j; for (i = 0; i < c->n_variants && variant_count < 2; i++) { struct variant *v = c->variants[i]; for (j = 0; j < v->n_playlists; j++) { if (v->playlists[j] == pls) { variant_count++; break; } } } return variant_count >= 2; } static void add_renditions_to_variant(HLSContext *c, struct variant *var, enum AVMediaType type, const char *group_id) { int i; for (i = 0; i < c->n_renditions; i++) { struct rendition *rend = c->renditions[i]; if (rend->type == type && !strcmp(rend->group_id, group_id)) { if (rend->playlist) /* rendition is an external playlist * => add the playlist to the variant */ dynarray_add(&var->playlists, &var->n_playlists, rend->playlist); else /* rendition is part of the variant main Media Playlist * => add the rendition to the main Media Playlist */ dynarray_add(&var->playlists[0]->renditions, &var->playlists[0]->n_renditions, rend); } } } static void add_metadata_from_renditions(AVFormatContext *s, struct playlist *pls, enum AVMediaType type) { int rend_idx = 0; int i; for (i = 0; i < pls->ctx->nb_streams; i++) { AVStream *st = s->streams[pls->stream_offset + i]; if (st->codec->codec_type != type) continue; for (; rend_idx < pls->n_renditions; rend_idx++) { struct rendition *rend = pls->renditions[rend_idx]; if (rend->type != type) continue; if (rend->language[0]) av_dict_set(&st->metadata, "language", rend->language, 0); if (rend->name[0]) av_dict_set(&st->metadata, "comment", rend->name, 0); st->disposition |= rend->disposition; } if (rend_idx >=pls->n_renditions) break; } } static int hls_read_header(AVFormatContext *s) { URLContext *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb->opaque; HLSContext *c = s->priv_data; int ret = 0, i, j, stream_offset = 0; c->interrupt_callback = &s->interrupt_callback; // if the URL context is good, read important options we must broker later if (u && u->prot->priv_data_class) { // get the previous user agent & set back to null if string size is zero av_freep(&c->user_agent); av_opt_get(u->priv_data, "user-agent", 0, (uint8_t**)&(c->user_agent)); if (c->user_agent && !strlen(c->user_agent)) av_freep(&c->user_agent); // get the previous cookies & set back to null if string size is zero av_freep(&c->cookies); av_opt_get(u->priv_data, "cookies", 0, (uint8_t**)&(c->cookies)); if (c->cookies && !strlen(c->cookies)) av_freep(&c->cookies); // get the previous headers & set back to null if string size is zero av_freep(&c->headers); av_opt_get(u->priv_data, "headers", 0, (uint8_t**)&(c->headers)); if (c->headers && !strlen(c->headers)) av_freep(&c->headers); } if ((ret = parse_playlist(c, s->filename, NULL, s->pb)) < 0) goto fail; if (c->n_variants == 0) { av_log(NULL, AV_LOG_WARNING, "Empty playlist\n"); ret = AVERROR_EOF; goto fail; } /* If the playlist only contained playlists (Master Playlist), * parse each individual playlist. */ if (c->n_playlists > 1 || c->playlists[0]->n_segments == 0) { for (i = 0; i < c->n_playlists; i++) { struct playlist *pls = c->playlists[i]; if ((ret = parse_playlist(c, pls->url, pls, NULL)) < 0) goto fail; } } if (c->variants[0]->playlists[0]->n_segments == 0) { av_log(NULL, AV_LOG_WARNING, "Empty playlist\n"); ret = AVERROR_EOF; goto fail; } /* If this isn't a live stream, calculate the total duration of the * stream. */ if (c->variants[0]->playlists[0]->finished) { int64_t duration = 0; for (i = 0; i < c->variants[0]->playlists[0]->n_segments; i++) duration += c->variants[0]->playlists[0]->segments[i]->duration; s->duration = duration; } /* Associate renditions with variants */ for (i = 0; i < c->n_variants; i++) { struct variant *var = c->variants[i]; if (var->audio_group[0]) add_renditions_to_variant(c, var, AVMEDIA_TYPE_AUDIO, var->audio_group); if (var->video_group[0]) add_renditions_to_variant(c, var, AVMEDIA_TYPE_VIDEO, var->video_group); if (var->subtitles_group[0]) add_renditions_to_variant(c, var, AVMEDIA_TYPE_SUBTITLE, var->subtitles_group); } /* Open the demuxer for each playlist */ for (i = 0; i < c->n_playlists; i++) { struct playlist *pls = c->playlists[i]; AVInputFormat *in_fmt = NULL; if (pls->n_segments == 0) continue; if (!(pls->ctx = avformat_alloc_context())) { ret = AVERROR(ENOMEM); goto fail; } pls->index = i; pls->needed = 1; pls->parent = s; /* If this is a live stream with more than 3 segments, start at the * third last segment. */ pls->cur_seq_no = pls->start_seq_no; if (!pls->finished && pls->n_segments > 3) pls->cur_seq_no = pls->start_seq_no + pls->n_segments - 3; pls->read_buffer = av_malloc(INITIAL_BUFFER_SIZE); ffio_init_context(&pls->pb, pls->read_buffer, INITIAL_BUFFER_SIZE, 0, pls, read_data, NULL, NULL); pls->pb.seekable = 0; ret = av_probe_input_buffer(&pls->pb, &in_fmt, pls->segments[0]->url, NULL, 0, 0); if (ret < 0) { /* Free the ctx - it isn't initialized properly at this point, * so avformat_close_input shouldn't be called. If * avformat_open_input fails below, it frees and zeros the * context, so it doesn't need any special treatment like this. */ av_log(s, AV_LOG_ERROR, "Error when loading first segment '%s'\n", pls->segments[0]->url); avformat_free_context(pls->ctx); pls->ctx = NULL; goto fail; } pls->ctx->pb = &pls->pb; pls->stream_offset = stream_offset; ret = avformat_open_input(&pls->ctx, pls->segments[0]->url, in_fmt, NULL); if (ret < 0) goto fail; pls->ctx->ctx_flags &= ~AVFMTCTX_NOHEADER; ret = avformat_find_stream_info(pls->ctx, NULL); if (ret < 0) goto fail; /* Create new AVStreams for each stream in this playlist */ for (j = 0; j < pls->ctx->nb_streams; j++) { AVStream *st = avformat_new_stream(s, NULL); AVStream *ist = pls->ctx->streams[j]; if (!st) { ret = AVERROR(ENOMEM); goto fail; } st->id = i; avpriv_set_pts_info(st, ist->pts_wrap_bits, ist->time_base.num, ist->time_base.den); avcodec_copy_context(st->codec, pls->ctx->streams[j]->codec); } add_metadata_from_renditions(s, pls, AVMEDIA_TYPE_AUDIO); add_metadata_from_renditions(s, pls, AVMEDIA_TYPE_VIDEO); add_metadata_from_renditions(s, pls, AVMEDIA_TYPE_SUBTITLE); stream_offset += pls->ctx->nb_streams; } /* Create a program for each variant */ for (i = 0; i < c->n_variants; i++) { struct variant *v = c->variants[i]; char bitrate_str[20]; AVProgram *program; snprintf(bitrate_str, sizeof(bitrate_str), "%d", v->bandwidth); program = av_new_program(s, i); if (!program) goto fail; av_dict_set(&program->metadata, "variant_bitrate", bitrate_str, 0); for (j = 0; j < v->n_playlists; j++) { struct playlist *pls = v->playlists[j]; int is_shared = playlist_in_multiple_variants(c, pls); int k; for (k = 0; k < pls->ctx->nb_streams; k++) { struct AVStream *st = s->streams[pls->stream_offset + k]; ff_program_add_stream_index(s, i, pls->stream_offset + k); /* Set variant_bitrate for streams unique to this variant */ if (!is_shared && v->bandwidth) av_dict_set(&st->metadata, "variant_bitrate", bitrate_str, 0); } } } c->first_packet = 1; c->first_timestamp = AV_NOPTS_VALUE; c->seek_timestamp = AV_NOPTS_VALUE; return 0; fail: free_playlist_list(c); free_variant_list(c); free_rendition_list(c); return ret; } static int recheck_discard_flags(AVFormatContext *s, int first) { HLSContext *c = s->priv_data; int i, changed = 0; /* Check if any new streams are needed */ for (i = 0; i < c->n_playlists; i++) c->playlists[i]->cur_needed = 0; for (i = 0; i < s->nb_streams; i++) { AVStream *st = s->streams[i]; struct playlist *pls = c->playlists[s->streams[i]->id]; if (st->discard < AVDISCARD_ALL) pls->cur_needed = 1; } for (i = 0; i < c->n_playlists; i++) { struct playlist *pls = c->playlists[i]; if (pls->cur_needed && !pls->needed) { pls->needed = 1; changed = 1; pls->cur_seq_no = c->cur_seq_no; pls->pb.eof_reached = 0; av_log(s, AV_LOG_INFO, "Now receiving playlist %d\n", i); } else if (first && !pls->cur_needed && pls->needed) { if (pls->input) ffurl_close(pls->input); pls->input = NULL; pls->needed = 0; changed = 1; av_log(s, AV_LOG_INFO, "No longer receiving playlist %d\n", i); } } return changed; } static int hls_read_packet(AVFormatContext *s, AVPacket *pkt) { HLSContext *c = s->priv_data; int ret, i, minplaylist = -1; if (c->first_packet) { recheck_discard_flags(s, 1); c->first_packet = 0; } start: c->end_of_segment = 0; for (i = 0; i < c->n_playlists; i++) { struct playlist *pls = c->playlists[i]; /* Make sure we've got one buffered packet from each open playlist * stream */ if (pls->needed && !pls->pkt.data) { while (1) { int64_t ts_diff; AVStream *st; ret = av_read_frame(pls->ctx, &pls->pkt); if (ret < 0) { if (!url_feof(&pls->pb) && ret != AVERROR_EOF) return ret; reset_packet(&pls->pkt); break; } else { if (c->first_timestamp == AV_NOPTS_VALUE && pls->pkt.dts != AV_NOPTS_VALUE) c->first_timestamp = av_rescale_q(pls->pkt.dts, pls->ctx->streams[pls->pkt.stream_index]->time_base, AV_TIME_BASE_Q); } if (c->seek_timestamp == AV_NOPTS_VALUE) break; if (pls->pkt.dts == AV_NOPTS_VALUE) { c->seek_timestamp = AV_NOPTS_VALUE; break; } st = pls->ctx->streams[pls->pkt.stream_index]; ts_diff = av_rescale_rnd(pls->pkt.dts, AV_TIME_BASE, st->time_base.den, AV_ROUND_DOWN) - c->seek_timestamp; if (ts_diff >= 0 && (c->seek_flags & AVSEEK_FLAG_ANY || pls->pkt.flags & AV_PKT_FLAG_KEY)) { c->seek_timestamp = AV_NOPTS_VALUE; break; } av_free_packet(&pls->pkt); reset_packet(&pls->pkt); } } /* Check if this stream still is on an earlier segment number, or * has the packet with the lowest dts */ if (pls->pkt.data) { struct playlist *minpls = minplaylist < 0 ? NULL : c->playlists[minplaylist]; if (minplaylist < 0 || pls->cur_seq_no < minpls->cur_seq_no) { minplaylist = i; } else if (pls->cur_seq_no == minpls->cur_seq_no) { int64_t dts = pls->pkt.dts; int64_t mindts = minpls->pkt.dts; AVStream *st = pls->ctx->streams[pls->pkt.stream_index]; AVStream *minst = minpls->ctx->streams[minpls->pkt.stream_index]; if (dts == AV_NOPTS_VALUE) { minplaylist = i; } else if (mindts != AV_NOPTS_VALUE) { if (st->start_time != AV_NOPTS_VALUE) dts -= st->start_time; if (minst->start_time != AV_NOPTS_VALUE) mindts -= minst->start_time; if (av_compare_ts(dts, st->time_base, mindts, minst->time_base) < 0) minplaylist = i; } } } } if (c->end_of_segment) { if (recheck_discard_flags(s, 0)) goto start; } /* If we got a packet, return it */ if (minplaylist >= 0) { *pkt = c->playlists[minplaylist]->pkt; pkt->stream_index += c->playlists[minplaylist]->stream_offset; reset_packet(&c->playlists[minplaylist]->pkt); return 0; } return AVERROR_EOF; } static int hls_close(AVFormatContext *s) { HLSContext *c = s->priv_data; free_playlist_list(c); free_variant_list(c); free_rendition_list(c); return 0; } static int hls_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) { HLSContext *c = s->priv_data; int i, j, ret; if ((flags & AVSEEK_FLAG_BYTE) || !c->variants[0]->playlists[0]->finished) return AVERROR(ENOSYS); c->seek_flags = flags; c->seek_timestamp = stream_index < 0 ? timestamp : av_rescale_rnd(timestamp, AV_TIME_BASE, s->streams[stream_index]->time_base.den, flags & AVSEEK_FLAG_BACKWARD ? AV_ROUND_DOWN : AV_ROUND_UP); timestamp = av_rescale_rnd(timestamp, AV_TIME_BASE, stream_index >= 0 ? s->streams[stream_index]->time_base.den : AV_TIME_BASE, flags & AVSEEK_FLAG_BACKWARD ? AV_ROUND_DOWN : AV_ROUND_UP); if (s->duration < c->seek_timestamp) { c->seek_timestamp = AV_NOPTS_VALUE; return AVERROR(EIO); } ret = AVERROR(EIO); for (i = 0; i < c->n_playlists; i++) { /* Reset reading */ struct playlist *pls = c->playlists[i]; int64_t pos = c->first_timestamp == AV_NOPTS_VALUE ? 0 : c->first_timestamp; if (pls->input) { ffurl_close(pls->input); pls->input = NULL; } av_free_packet(&pls->pkt); reset_packet(&pls->pkt); pls->pb.eof_reached = 0; /* Clear any buffered data */ pls->pb.buf_end = pls->pb.buf_ptr = pls->pb.buffer; /* Reset the pos, to let the mpegts demuxer know we've seeked. */ pls->pb.pos = 0; /* Locate the segment that contains the target timestamp */ for (j = 0; j < pls->n_segments; j++) { if (timestamp >= pos && timestamp < pos + pls->segments[j]->duration) { pls->cur_seq_no = pls->start_seq_no + j; ret = 0; break; } pos += pls->segments[j]->duration; } if (ret) c->seek_timestamp = AV_NOPTS_VALUE; } return ret; } static int hls_probe(AVProbeData *p) { /* Require #EXTM3U at the start, and either one of the ones below * somewhere for a proper match. */ if (strncmp(p->buf, "#EXTM3U", 7)) return 0; if (strstr(p->buf, "#EXT-X-STREAM-INF:") || strstr(p->buf, "#EXT-X-TARGETDURATION:") || strstr(p->buf, "#EXT-X-MEDIA-SEQUENCE:")) return AVPROBE_SCORE_MAX; return 0; } AVInputFormat ff_hls_demuxer = { .name = "hls,applehttp", .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"), .priv_data_size = sizeof(HLSContext), .read_probe = hls_probe, .read_header = hls_read_header, .read_packet = hls_read_packet, .read_close = hls_close, .read_seek = hls_read_seek, };