[FFmpeg-devel] [PATCH] wtvenc: test avio_size() validity

[Peter Ross]

---
On Sun, Dec 22, 2013 at 08:10:54AM +0100, Reimar Döffinger wrote:
> On 21.12.2013, at 09:42, Peter Ross <pross at xvid.org> wrote:
> > Previously the demuxer was testing against avio_tell, and this would generate
> > many false warnings.
> 
> Do we support streaming (or otherwise non-seekable) wtv files?

Not currently. The filesystem-like nature of wtv means that (lots of) seeking is almost always
required. It is theorectically to craft a file that does require seeking.

> I suspect not, but to be correct for that case it would need to check that avio_size is valid first...

I agree.

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

diff --git a/libavformat/wtvdec.c b/libavformat/wtvdec.c
index 5069d48..21236fa 100644
--- a/libavformat/wtvdec.c
+++ b/libavformat/wtvdec.c
@@ -153,6 +153,7 @@ static AVIOContext * wtvfile_open_sector(int first_sector, uint64_t length, int
     AVIOContext *pb;
     WtvFile *wf;
     uint8_t *buffer;
+    int64_t size;
 
     if (seek_by_sector(s->pb, first_sector, 0) < 0)
         return NULL;
@@ -205,7 +206,8 @@ static AVIOContext * wtvfile_open_sector(int first_sector, uint64_t length, int
         return NULL;
     }
 
-    if ((int64_t)wf->sectors[wf->nb_sectors - 1] << WTV_SECTOR_BITS > avio_size(s->pb))
+    size = avio_size(s->pb);
+    if (size >= 0 && (int64_t)wf->sectors[wf->nb_sectors - 1] << WTV_SECTOR_BITS > size)
         av_log(s, AV_LOG_WARNING, "truncated file\n");
 
     /* check length */
-- 
1.8.3.2

-- Peter
(A907 E02F A6E5 0CD2 34CD 20D2 6760 79C5 AC40 DD6B)
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