Check context before accessing its field.

[ffmpeg] / libavformat / ogg2.c

diff --git a/libavformat/ogg2.c b/libavformat/ogg2.c
index 9e6e1539b648d0fadad2bd835df801aab5eb16ec..ebc7567d58f88fa55d341a942941b104a2a4801d 100644 (file)
--- a/libavformat/ogg2.c
+++ b/libavformat/ogg2.c
@@ -41,6 +41,7 @@ static ogg_codec_t *ogg_codecs[] = {
     &vorbis_codec,
     &theora_codec,
     &flac_codec,
+    &old_flac_codec,
     &ogm_video_codec,
     &ogm_audio_codec,
     &ogm_old_codec,
@@ -67,8 +68,8 @@ ogg_write_trailer (AVFormatContext * avfcontext)
 
 AVOutputFormat ogg_muxer = {
     "ogg",
-    "Ogg Vorbis",
-    "audio/x-vorbis",
+    "Ogg format",
+    "application/ogg",
     "ogg",
     sizeof (OggContext),
     CODEC_ID_VORBIS,
@@ -90,6 +91,7 @@ ogg_save (AVFormatContext * s)
     ost->pos = url_ftell (&s->pb);;
     ost->curidx = ogg->curidx;
     ost->next = ogg->state;
+    ost->nstreams = ogg->nstreams;
     memcpy(ost->streams, ogg->streams, ogg->nstreams * sizeof(*ogg->streams));
 
     for (i = 0; i < ogg->nstreams; i++){
@@ -123,8 +125,9 @@ ogg_restore (AVFormatContext * s, int discard)
 
         url_fseek (bc, ost->pos, SEEK_SET);
         ogg->curidx = ost->curidx;
-        memcpy (ogg->streams, ost->streams,
-        ogg->nstreams * sizeof (*ogg->streams));
+        ogg->nstreams = ost->nstreams;
+        memcpy(ogg->streams, ost->streams,
+               ost->nstreams * sizeof(*ogg->streams));
     }
 
     av_free (ost);
@@ -198,7 +201,7 @@ ogg_new_stream (AVFormatContext * s, uint32_t serial)
 
     st = av_new_stream (s, idx);
     if (!st)
-        return AVERROR_NOMEM;
+        return AVERROR(ENOMEM);
 
     av_set_pts_info(st, 64, 1, 1000000);
 
@@ -482,7 +485,8 @@ ogg_get_length (AVFormatContext * s)
     url_fseek (&s->pb, end, SEEK_SET);
 
     while (!ogg_read_page (s, &i)){
-        if (ogg->streams[i].granule != -1 && ogg->streams[i].granule != 0)
+        if (ogg->streams[i].granule != -1 && ogg->streams[i].granule != 0 &&
+            ogg->streams[i].codec)
             idx = i;
     }
 
@@ -494,7 +498,7 @@ ogg_get_length (AVFormatContext * s)
     ogg->size = size;
     ogg_restore (s, 0);
     ogg_save (s);
-    while (ogg_read_page (s, &i)) {
+    while (!ogg_read_page (s, &i)) {
         if (i == idx && ogg->streams[i].granule != -1 && ogg->streams[i].granule != 0)
             break;
     }
@@ -537,7 +541,7 @@ ogg_read_packet (AVFormatContext * s, AVPacket * pkt)
     //Get an ogg packet
     do{
         if (ogg_packet (s, &idx, &pstart, &psize) < 0)
-            return AVERROR_IO;
+            return AVERROR(EIO);
     }while (idx < 0 || !s->streams[idx]);
 
     ogg = s->priv_data;
@@ -545,7 +549,7 @@ ogg_read_packet (AVFormatContext * s, AVPacket * pkt)
 
     //Alloc a pkt
     if (av_new_packet (pkt, psize) < 0)
-        return AVERROR_IO;
+        return AVERROR(EIO);
     pkt->stream_index = idx;
     memcpy (pkt->data, os->buf + pstart, psize);
     if (os->lastgp != -1LL){
@@ -572,109 +576,31 @@ ogg_read_close (AVFormatContext * s)
 }
 
 
-static int
-ogg_read_seek (AVFormatContext * s, int stream_index, int64_t target_ts,
-               int flags)
+static int64_t
+ogg_read_timestamp (AVFormatContext * s, int stream_index, int64_t * pos_arg,
+                    int64_t pos_limit)
 {
-    AVStream *st = s->streams[stream_index];
     ogg_t *ogg = s->priv_data;
     ByteIOContext *bc = &s->pb;
-    uint64_t min = 0, max = ogg->size;
-    uint64_t tmin = st->start_time, tmax = st->start_time + st->duration;
     int64_t pts = AV_NOPTS_VALUE;
-
-    ogg_save (s);
-
-    if ((uint64_t)target_ts < tmin || target_ts < 0)
-        target_ts = tmin;
-    while (min <= max && tmin < tmax){
-        uint64_t p = min + (max - min) * (target_ts - tmin) / (tmax - tmin);
-        int i = -1;
-
-        url_fseek (bc, p, SEEK_SET);
-
-        while (!ogg_read_page (s, &i)){
-            if (i == stream_index && ogg->streams[i].granule != 0 &&
-                ogg->streams[i].granule != -1)
-                break;
-        }
-
-        if (i == -1)
-            break;
-
-        pts = ogg_gptopts (s, i, ogg->streams[i].granule);
-        p = url_ftell (bc);
-
-        if (ABS (pts - target_ts) * st->time_base.num < st->time_base.den)
+    int i;
+    url_fseek(bc, *pos_arg, SEEK_SET);
+    while (url_ftell(bc) < pos_limit && !ogg_read_page (s, &i)) {
+        if (ogg->streams[i].granule != -1 && ogg->streams[i].granule != 0 &&
+            ogg->streams[i].codec && i == stream_index) {
+            pts = ogg_gptopts(s, i, ogg->streams[i].granule);
+            // FIXME: this is the position of the packet after the one with above
+            // pts.
+            *pos_arg = url_ftell(bc);
             break;
-
-        if (pts > target_ts){
-            if (max == p && tmax == pts) {
-                // probably our tmin is wrong, causing us to always end up too late in the file
-                tmin = (target_ts + tmin + 1) / 2;
-                if (tmin == target_ts) {
-                    url_fseek(bc, min, SEEK_SET);
-                    break;
-                }
-            }
-            max = p;
-            tmax = pts;
-        }else{
-            if (min == p && tmin == pts) {
-                // probably our tmax is wrong, causing us to always end up too early in the file
-                tmax = (target_ts + tmax) / 2;
-                if (tmax == target_ts) {
-                    url_fseek(bc, max, SEEK_SET);
-                    break;
-                }
-            }
-            min = p;
-            tmin = pts;
         }
     }
-
-    if (ABS (pts - target_ts) * st->time_base.num < st->time_base.den){
-        ogg_restore (s, 1);
-        ogg_reset (ogg);
-    }else{
-        ogg_restore (s, 0);
-        pts = AV_NOPTS_VALUE;
-    }
-
-    av_update_cur_dts(s, st, pts);
-    return 0;
-
-#if 0
-    //later...
-    int64_t pos;
-    if (av_seek_frame_binary (s, stream_index, target_ts, flags) < 0)
-        return -1;
-    pos = url_ftell (&s->pb);
-    ogg_read_timestamp (s, stream_index, &pos, pos - 1);
-#endif
-
-}
-
-#if 0
-static int64_t
-ogg_read_timestamp (AVFormatContext * s, int stream_index, int64_t * pos_arg,
-                    int64_t pos_limit)
-{
-    ogg_t *ogg = s->priv_data;
-    ByteIOContext *bc = &s->pb;
-    int64_t pos, pts;
-
-    if (*pos_arg < 0)
-        return AV_NOPTS_VALUE;
-
-    pos = *pos_arg;
+    ogg_reset(ogg);
+    return pts;
 }
-#endif
 
 static int ogg_probe(AVProbeData *p)
 {
-    if (p->buf_size < 6)
-        return 0;
     if (p->buf[0] == 'O' && p->buf[1] == 'g' &&
         p->buf[2] == 'g' && p->buf[3] == 'S' &&
         p->buf[4] == 0x0 && p->buf[5] <= 0x7 )
@@ -691,7 +617,7 @@ AVInputFormat ogg_demuxer = {
     ogg_read_header,
     ogg_read_packet,
     ogg_read_close,
-    ogg_read_seek,
-// ogg_read_timestamp,
+    NULL,
+    ogg_read_timestamp,
     .extensions = "ogg",
 };