[FFmpeg-cvslog] lavf/utils: add error check in av_read_frame()

[Stefano Sabatini]

ffmpeg | branch: master | Stefano Sabatini <stefasab at gmail.com> | Mon Sep 24 00:33:15 2012 +0200| [64d340c62ad5954c1a834df2d26057135e771774] | committer: Stefano Sabatini

lavf/utils: add error check in av_read_frame()

In particular, fix crash when the input file contains no packets (e.g. an
ffmeta input).

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=64d340c62ad5954c1a834df2d26057135e771774
---

 libavformat/utils.c |   17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/libavformat/utils.c b/libavformat/utils.c
index 6603483..4f3529a 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -1409,11 +1409,18 @@ int av_read_frame(AVFormatContext *s, AVPacket *pkt)
     AVStream *st;
 
     if (!genpts) {
-        ret = s->packet_buffer ? read_from_packet_buffer(&s->packet_buffer,
-                                                          &s->packet_buffer_end,
-                                                          pkt) :
-                                  read_frame_internal(s, pkt);
-        goto return_packet;
+        while (1) {
+            ret = s->packet_buffer ?
+                read_from_packet_buffer(&s->packet_buffer, &s->packet_buffer_end, pkt) :
+                read_frame_internal(s, pkt);
+            if (ret < 0) {
+                if (ret == AVERROR(EAGAIN))
+                    continue;
+                else
+                    return ret;
+            }
+            goto return_packet;
+        }
     }
 
     for (;;) {