[FFmpeg-cvslog] avformat/mpegts: fix resync seek

[Michael Niedermayer]

ffmpeg | branch: release/2.1 | Michael Niedermayer <michaelni at gmx.at> | Mon Nov 18 16:38:12 2013 +0100| [a289b0b91a799a3db6cb5bebb628132863d632e4] | committer: Carl Eugen Hoyos

avformat/mpegts: fix resync seek

The seek ended up seeking before the begin, which caused problems
Fixes initial sync issues with libbluray
Fixes Ticket3117

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
(cherry picked from commit 7d0e927a31edb5fb584c2ab17f7fd676838d6639)

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=a289b0b91a799a3db6cb5bebb628132863d632e4
---

 libavformat/mpegts.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c
index 5f2dfe9..fe4ac35 100644
--- a/libavformat/mpegts.c
+++ b/libavformat/mpegts.c
@@ -1976,7 +1976,9 @@ static int read_packet(AVFormatContext *s, uint8_t *buf, int raw_packet_size, co
         /* check packet sync byte */
         if ((*data)[0] != 0x47) {
             /* find a new packet start */
-            avio_seek(pb, -raw_packet_size, SEEK_CUR);
+            uint64_t pos = avio_tell(pb);
+            avio_seek(pb, -FFMIN(raw_packet_size, pos), SEEK_CUR);
+
             if (mpegts_resync(s) < 0)
                 return AVERROR(EAGAIN);
             else