From f4f4e12c0d4e86c4900481b7dca94d22e733c14a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Martin=20Storsj=C3=B6?= Date: Thu, 22 Jul 2010 10:30:15 +0300 Subject: [PATCH] Add Apple HTTP Live Streaming protocol handler Signed-off-by: Luca Barbato --- doc/general.texi | 1 + libavformat/Makefile | 1 + libavformat/allformats.c | 1 + libavformat/applehttpproto.c | 358 +++++++++++++++++++++++++++++++++++ 4 files changed, 361 insertions(+) create mode 100644 libavformat/applehttpproto.c diff --git a/doc/general.texi b/doc/general.texi index cd126f9868..b7fd12938c 100644 --- a/doc/general.texi +++ b/doc/general.texi @@ -707,6 +707,7 @@ performance on systems without hardware floating point support). @multitable @columnfractions .4 .1 @item Name @tab Support +@item Apple HTTP Live Streaming @tab X @item file @tab X @item Gopher @tab X @item HTTP @tab X diff --git a/libavformat/Makefile b/libavformat/Makefile index f319031c26..eb9ca49e4d 100644 --- a/libavformat/Makefile +++ b/libavformat/Makefile @@ -308,6 +308,7 @@ OBJS-$(CONFIG_LIBNUT_MUXER) += libnut.o riff.o # protocols I/O OBJS+= avio.o aviobuf.o +OBJS-$(CONFIG_APPLEHTTP_PROTOCOL) += applehttpproto.o OBJS-$(CONFIG_CONCAT_PROTOCOL) += concat.o OBJS-$(CONFIG_FILE_PROTOCOL) += file.o OBJS-$(CONFIG_GOPHER_PROTOCOL) += gopher.o diff --git a/libavformat/allformats.c b/libavformat/allformats.c index 0ff4b5aa8e..562f6248a5 100644 --- a/libavformat/allformats.c +++ b/libavformat/allformats.c @@ -229,6 +229,7 @@ void av_register_all(void) REGISTER_MUXDEMUX (LIBNUT, libnut); /* protocols */ + REGISTER_PROTOCOL (APPLEHTTP, applehttp); REGISTER_PROTOCOL (CONCAT, concat); REGISTER_PROTOCOL (FILE, file); REGISTER_PROTOCOL (GOPHER, gopher); diff --git a/libavformat/applehttpproto.c b/libavformat/applehttpproto.c new file mode 100644 index 0000000000..471f94bd2a --- /dev/null +++ b/libavformat/applehttpproto.c @@ -0,0 +1,358 @@ +/* + * Apple HTTP Live Streaming Protocol Handler + * Copyright (c) 2010 Martin Storsjo + * + * 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 Protocol Handler + * http://tools.ietf.org/html/draft-pantos-http-live-streaming + */ + +#define _XOPEN_SOURCE 600 +#include "libavutil/avstring.h" +#include "avformat.h" +#include "internal.h" +#include + +/* + * 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 (preferrably 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. + */ + +struct segment { + int duration; + char url[MAX_URL_SIZE]; +}; + +struct variant { + int bandwidth; + char url[MAX_URL_SIZE]; +}; + +typedef struct AppleHTTPContext { + char playlisturl[MAX_URL_SIZE]; + int target_duration; + int start_seq_no; + int finished; + int n_segments; + struct segment **segments; + int n_variants; + struct variant **variants; + int cur_seq_no; + URLContext *seg_hd; + int64_t last_load_time; +} AppleHTTPContext; + +static int read_chomp_line(AVIOContext *s, char *buf, int maxlen) +{ + int len = ff_get_line(s, buf, maxlen); + while (len > 0 && isspace(buf[len - 1])) + buf[--len] = '\0'; + return len; +} + +static void make_absolute_url(char *buf, int size, const char *base, + const char *rel) +{ + char *sep; + /* Absolute path, relative to the current server */ + if (base && strstr(base, "://") && rel[0] == '/') { + if (base != buf) + av_strlcpy(buf, base, size); + sep = strstr(buf, "://"); + if (sep) { + sep += 3; + sep = strchr(sep, '/'); + if (sep) + *sep = '\0'; + } + av_strlcat(buf, rel, size); + return; + } + /* If rel actually is an absolute url, just copy it */ + if (!base || strstr(rel, "://") || rel[0] == '/') { + av_strlcpy(buf, rel, size); + return; + } + if (base != buf) + av_strlcpy(buf, base, size); + /* Remove the file name from the base url */ + sep = strrchr(buf, '/'); + if (sep) + sep[1] = '\0'; + else + buf[0] = '\0'; + while (av_strstart(rel, "../", NULL) && sep) { + /* Remove the path delimiter at the end */ + sep[0] = '\0'; + sep = strrchr(buf, '/'); + /* If the next directory name to pop off is "..", break here */ + if (!strcmp(sep ? &sep[1] : buf, "..")) { + /* Readd the slash we just removed */ + av_strlcat(buf, "/", size); + break; + } + /* Cut off the directory name */ + if (sep) + sep[1] = '\0'; + else + buf[0] = '\0'; + rel += 3; + } + av_strlcat(buf, rel, size); +} + +static void free_segment_list(AppleHTTPContext *s) +{ + int i; + for (i = 0; i < s->n_segments; i++) + av_free(s->segments[i]); + av_freep(&s->segments); + s->n_segments = 0; +} + +static void free_variant_list(AppleHTTPContext *s) +{ + int i; + for (i = 0; i < s->n_variants; i++) + av_free(s->variants[i]); + av_freep(&s->variants); + s->n_variants = 0; +} + +struct variant_info { + char bandwidth[20]; +}; + +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); + } +} + +static int parse_playlist(URLContext *h, const char *url) +{ + AppleHTTPContext *s = h->priv_data; + AVIOContext *in; + int ret = 0, duration = 0, is_segment = 0, is_variant = 0, bandwidth = 0; + char line[1024]; + const char *ptr; + + if ((ret = avio_open(&in, url, URL_RDONLY)) < 0) + return ret; + + read_chomp_line(in, line, sizeof(line)); + if (strcmp(line, "#EXTM3U")) + return AVERROR_INVALIDDATA; + + free_segment_list(s); + s->finished = 0; + while (!url_feof(in)) { + read_chomp_line(in, line, sizeof(line)); + if (av_strstart(line, "#EXT-X-STREAM-INF:", &ptr)) { + struct variant_info info = {{0}}; + is_variant = 1; + ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_variant_args, + &info); + bandwidth = atoi(info.bandwidth); + } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) { + s->target_duration = atoi(ptr); + } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) { + s->start_seq_no = atoi(ptr); + } else if (av_strstart(line, "#EXT-X-ENDLIST", &ptr)) { + s->finished = 1; + } else if (av_strstart(line, "#EXTINF:", &ptr)) { + is_segment = 1; + duration = atoi(ptr); + } else if (av_strstart(line, "#", NULL)) { + continue; + } else if (line[0]) { + if (is_segment) { + struct segment *seg = av_malloc(sizeof(struct segment)); + if (!seg) { + ret = AVERROR(ENOMEM); + goto fail; + } + seg->duration = duration; + make_absolute_url(seg->url, sizeof(seg->url), url, line); + dynarray_add(&s->segments, &s->n_segments, seg); + is_segment = 0; + } else if (is_variant) { + struct variant *var = av_malloc(sizeof(struct variant)); + if (!var) { + ret = AVERROR(ENOMEM); + goto fail; + } + var->bandwidth = bandwidth; + make_absolute_url(var->url, sizeof(var->url), url, line); + dynarray_add(&s->variants, &s->n_variants, var); + is_variant = 0; + } + } + } + s->last_load_time = av_gettime(); + +fail: + avio_close(in); + return ret; +} + +static int applehttp_open(URLContext *h, const char *uri, int flags) +{ + AppleHTTPContext *s; + int ret, i; + const char *nested_url; + + if (flags & (URL_WRONLY | URL_RDWR)) + return AVERROR_NOTSUPP; + + s = av_mallocz(sizeof(AppleHTTPContext)); + if (!s) + return AVERROR(ENOMEM); + h->priv_data = s; + h->is_streamed = 1; + + if (av_strstart(uri, "applehttp+", &nested_url)) { + av_strlcpy(s->playlisturl, nested_url, sizeof(s->playlisturl)); + } else if (av_strstart(uri, "applehttp://", &nested_url)) { + av_strlcpy(s->playlisturl, "http://", sizeof(s->playlisturl)); + av_strlcat(s->playlisturl, nested_url, sizeof(s->playlisturl)); + } else { + av_log(NULL, AV_LOG_ERROR, "Unsupported url %s\n", uri); + ret = AVERROR(EINVAL); + goto fail; + } + + if ((ret = parse_playlist(h, s->playlisturl)) < 0) + goto fail; + + if (s->n_segments == 0 && s->n_variants > 0) { + int max_bandwidth = 0, maxvar = -1; + for (i = 0; i < s->n_variants; i++) { + if (s->variants[i]->bandwidth > max_bandwidth || i == 0) { + max_bandwidth = s->variants[i]->bandwidth; + maxvar = i; + } + } + av_strlcpy(s->playlisturl, s->variants[maxvar]->url, + sizeof(s->playlisturl)); + if ((ret = parse_playlist(h, s->playlisturl)) < 0) + goto fail; + } + + if (s->n_segments == 0) { + av_log(NULL, AV_LOG_WARNING, "Empty playlist\n"); + ret = AVERROR(EIO); + goto fail; + } + s->cur_seq_no = s->start_seq_no; + if (!s->finished && s->n_segments >= 3) + s->cur_seq_no = s->start_seq_no + s->n_segments - 3; + + return 0; + +fail: + av_free(s); + return ret; +} + +static int applehttp_read(URLContext *h, uint8_t *buf, int size) +{ + AppleHTTPContext *s = h->priv_data; + const char *url; + int ret; + +start: + if (s->seg_hd) { + ret = url_read(s->seg_hd, buf, size); + if (ret > 0) + return ret; + } + if (s->seg_hd) { + url_close(s->seg_hd); + s->seg_hd = NULL; + s->cur_seq_no++; + } +retry: + if (!s->finished) { + int64_t now = av_gettime(); + if (now - s->last_load_time >= s->target_duration*1000000) + if ((ret = parse_playlist(h, s->playlisturl)) < 0) + return ret; + } + if (s->cur_seq_no < s->start_seq_no) { + av_log(NULL, AV_LOG_WARNING, + "skipping %d segments ahead, expired from playlist\n", + s->start_seq_no - s->cur_seq_no); + s->cur_seq_no = s->start_seq_no; + } + if (s->cur_seq_no - s->start_seq_no >= s->n_segments) { + if (s->finished) + return AVERROR_EOF; + while (av_gettime() - s->last_load_time < s->target_duration*1000000) { + if (url_interrupt_cb()) + return AVERROR(EINTR); + usleep(100*1000); + } + goto retry; + } + url = s->segments[s->cur_seq_no - s->start_seq_no]->url, + av_log(NULL, AV_LOG_DEBUG, "opening %s\n", url); + ret = url_open(&s->seg_hd, url, URL_RDONLY); + if (ret < 0) { + if (url_interrupt_cb()) + return AVERROR(EINTR); + av_log(NULL, AV_LOG_WARNING, "Unable to open %s\n", url); + s->cur_seq_no++; + goto retry; + } + goto start; +} + +static int applehttp_close(URLContext *h) +{ + AppleHTTPContext *s = h->priv_data; + + free_segment_list(s); + free_variant_list(s); + url_close(s->seg_hd); + av_free(s); + return 0; +} + +URLProtocol ff_applehttp_protocol = { + "applehttp", + applehttp_open, + applehttp_read, + NULL, /* write */ + NULL, /* seek */ + applehttp_close, + .flags = URL_PROTOCOL_FLAG_NESTED_SCHEME, +};