[MPlayer-users] Crash seeking to chapters in a multi-VTS DVD if title is gt 1

[Nico Sabbi]

Il giorno mer, 31/12/2008 alle 15.06 +0100, Reimar Döffinger ha scritto:
> On Wed, Dec 31, 2008 at 12:33:22PM +0100, Nico Sabbi wrote:
> > are you sure the bug is present in current svn? I can't reproduce the
> > bug: set_property chapter never crashes for me, nether with
> > CHAPTER >= max
> > nor with CHAPTER < 1
> 
> crashes no, but hangs, which IMO are caused by libdvdreads horrible API.
> The problem is when the selected chapter is at or after the end of the
> DVD.
> In stream_dvd.c there is this code:
> >  len = DVDReadBlocks(d->title, d->cur_pack, 1, data);
> >  if(!len) return -1; //error
> 
> AFAICT the dvdread API is supposed to return 0 on error (I have no clue
> what then the point is of allowing negative values, since I can't see
> how they would make any sense, I only see this API behaviour bloating up
> the libdvdread code for no good reason).
> Problem is, dvdcss read function may also return negative values on read
> errors, and the return values of dvdcss are passed through.
> So we will end up with len < 0 here and thus an endless loop.
> Changing !len to len <= 0 fixes it, and while I am in favour of such a
> fix it breaks the dvdread API.
> 

thanks for fixing it :)