[FFmpeg-cvslog] Fix segfault on UDP reading

[Andrey Utkin]

ffmpeg | branch: master | Andrey Utkin <andrey.krieger.utkin at gmail.com> | Thu Nov  3 07:00:15 2011 +0000| [7a032cb97f743a651138d2da6214c79e0ce089dd] | committer: Michael Niedermayer

Fix segfault on UDP reading

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7a032cb97f743a651138d2da6214c79e0ce089dd
---

 libavformat/udp.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/libavformat/udp.c b/libavformat/udp.c
index 151e070..59d1f74 100644
--- a/libavformat/udp.c
+++ b/libavformat/udp.c
@@ -546,15 +546,19 @@ static int udp_read(URLContext *h, uint8_t *buf, int size)
             avail = av_fifo_size(s->fifo);
             if (avail) { // >=size) {
                 uint8_t tmp[4];
+                int skip = 0;
 
                 av_fifo_generic_read(s->fifo, tmp, 4, NULL);
                 avail= AV_RL32(tmp);
                 if(avail > size){
                     av_log(h, AV_LOG_WARNING, "Part of datagram lost due to insufficient buffer size\n");
+                    skip = avail - size;
                     avail= size;
                 }
 
                 av_fifo_generic_read(s->fifo, buf, avail, NULL);
+                if (skip)
+                    av_fifo_drain(s->fifo, skip);
                 return avail;
             }
             else {