--- /dev/null
+/*
+ * 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 <unistd.h>
+
+/*
+ * 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,
+};
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