ffmpeg-2.1.1: move directory

git-svn-id: svn://kolibrios.org@6148 a494cfbc-eb01-0410-851d-a64ba20cac60

contrib/sdk/sources/ffmpeg/ffmpeg-2.1/libavformat/hlsproto.c

@@ -0,0 +1,323 @@
+/*
+ * 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
+ */
+
+#include "libavutil/avstring.h"
+#include "libavutil/time.h"
+#include "avformat.h"
+#include "internal.h"
+#include "url.h"
+#include "version.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 (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.
+ */
+
+struct segment {
+    int64_t duration;
+    char url[MAX_URL_SIZE];
+};
+
+struct variant {
+    int bandwidth;
+    char url[MAX_URL_SIZE];
+};
+
+typedef struct HLSContext {
+    char playlisturl[MAX_URL_SIZE];
+    int64_t 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;
+} 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(HLSContext *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(HLSContext *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)
+{
+    HLSContext *s = h->priv_data;
+    AVIOContext *in;
+    int ret = 0, is_segment = 0, is_variant = 0, bandwidth = 0;
+    int64_t duration = 0;
+    char line[1024];
+    const char *ptr;
+
+    if ((ret = avio_open2(&in, url, AVIO_FLAG_READ,
+                          &h->interrupt_callback, NULL)) < 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) * AV_TIME_BASE;
+        } 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 = atof(ptr) * AV_TIME_BASE;
+        } 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;
+                ff_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;
+                ff_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 hls_close(URLContext *h)
+{
+    HLSContext *s = h->priv_data;
+
+    free_segment_list(s);
+    free_variant_list(s);
+    ffurl_close(s->seg_hd);
+    return 0;
+}
+
+static int hls_open(URLContext *h, const char *uri, int flags)
+{
+    HLSContext *s = h->priv_data;
+    int ret, i;
+    const char *nested_url;
+
+    if (flags & AVIO_FLAG_WRITE)
+        return AVERROR(ENOSYS);
+
+    h->is_streamed = 1;
+
+    if (av_strstart(uri, "hls+", &nested_url)) {
+        av_strlcpy(s->playlisturl, nested_url, sizeof(s->playlisturl));
+    } else if (av_strstart(uri, "hls://", &nested_url)) {
+        av_log(h, AV_LOG_ERROR,
+               "No nested protocol specified. Specify e.g. hls+http://%s\n",
+               nested_url);
+        ret = AVERROR(EINVAL);
+        goto fail;
+    } else {
+        av_log(h, AV_LOG_ERROR, "Unsupported url %s\n", uri);
+        ret = AVERROR(EINVAL);
+        goto fail;
+    }
+    av_log(h, AV_LOG_WARNING,
+           "Using the hls protocol is discouraged, please try using the "
+           "hls demuxer instead. The hls demuxer should be more complete "
+           "and work as well as the protocol implementation. (If not, "
+           "please report it.) To use the demuxer, simply use %s as url.\n",
+           s->playlisturl);
+
+    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(h, 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:
+    hls_close(h);
+    return ret;
+}
+
+static int hls_read(URLContext *h, uint8_t *buf, int size)
+{
+    HLSContext *s = h->priv_data;
+    const char *url;
+    int ret;
+    int64_t reload_interval;
+
+start:
+    if (s->seg_hd) {
+        ret = ffurl_read(s->seg_hd, buf, size);
+        if (ret > 0)
+            return ret;
+    }
+    if (s->seg_hd) {
+        ffurl_close(s->seg_hd);
+        s->seg_hd = NULL;
+        s->cur_seq_no++;
+    }
+    reload_interval = s->n_segments > 0 ?
+                      s->segments[s->n_segments - 1]->duration :
+                      s->target_duration;
+retry:
+    if (!s->finished) {
+        int64_t now = av_gettime();
+        if (now - s->last_load_time >= reload_interval) {
+            if ((ret = parse_playlist(h, s->playlisturl)) < 0)
+                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 = s->target_duration / 2;
+        }
+    }
+    if (s->cur_seq_no < s->start_seq_no) {
+        av_log(h, 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 < reload_interval) {
+            if (ff_check_interrupt(&h->interrupt_callback))
+                return AVERROR_EXIT;
+            av_usleep(100*1000);
+        }
+        goto retry;
+    }
+    url = s->segments[s->cur_seq_no - s->start_seq_no]->url,
+    av_log(h, AV_LOG_DEBUG, "opening %s\n", url);
+    ret = ffurl_open(&s->seg_hd, url, AVIO_FLAG_READ,
+                     &h->interrupt_callback, NULL);
+    if (ret < 0) {
+        if (ff_check_interrupt(&h->interrupt_callback))
+            return AVERROR_EXIT;
+        av_log(h, AV_LOG_WARNING, "Unable to open %s\n", url);
+        s->cur_seq_no++;
+        goto retry;
+    }
+    goto start;
+}
+
+URLProtocol ff_hls_protocol = {
+    .name           = "hls",
+    .url_open       = hls_open,
+    .url_read       = hls_read,
+    .url_close      = hls_close,
+    .flags          = URL_PROTOCOL_FLAG_NESTED_SCHEME,
+    .priv_data_size = sizeof(HLSContext),
+};