avformat/oggdec: Respect AVERROR codes returned by ogg parsers.

Fixes ticket #6804. All of the ogg header and packet parsers may
return standard AVERROR codes; these return values should not be
treated as success.

Additionally changes oggparsevorbis, to not give up too early
with certain types of poorly muxed files.
Signed-off-by: Dale Curtis <dalecurtis@chromium.org>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavformat/oggdec.c

@@ -543,7 +543,11 @@ static int ogg_packet(AVFormatContext *s, int *sid, int *dstart, int *dsize,
     os->incomplete = 0;
 
     if (os->header) {
-        os->header = os->codec->header(s, idx);
+        if ((ret = os->codec->header(s, idx)) < 0) {
+            av_log(s, AV_LOG_ERROR, "Header processing failed: %s\n", av_err2str(ret));
+            return ret;
+        }
+        os->header = ret;
         if (!os->header) {
             os->segp  = segp;
             os->psize = psize;
@@ -574,8 +578,12 @@ static int ogg_packet(AVFormatContext *s, int *sid, int *dstart, int *dsize,
     } else {
         os->pflags    = 0;
         os->pduration = 0;
-        if (os->codec && os->codec->packet)
-            os->codec->packet(s, idx);
+        if (os->codec && os->codec->packet) {
+            if ((ret = os->codec->packet(s, idx)) < 0) {
+                av_log(s, AV_LOG_ERROR, "Packet processing failed: %s\n", av_err2str(ret));
+                return ret;
+            }
+        }
         if (sid)
             *sid = idx;
         if (dstart)

libavformat/oggparsevorbis.c

@@ -317,7 +317,7 @@ static int vorbis_header(AVFormatContext *s, int idx)
     if (priv->packet[pkt_type >> 1])
         return AVERROR_INVALIDDATA;
     if (pkt_type > 1 && !priv->packet[0] || pkt_type > 3 && !priv->packet[1])
-        return AVERROR_INVALIDDATA;
+        return priv->vp ? 0 : AVERROR_INVALIDDATA;
 
     priv->len[pkt_type >> 1]    = os->psize;
     priv->packet[pkt_type >> 1] = av_mallocz(os->psize);