[alsa-devel] softvol and snd_pcm_rewind() is broken

[Takashi Iwai]

At Fri, 18 Jul 2008 21:30:17 +0200,
Lennart Poettering wrote:
> 
> On Thu, 17.07.08 11:56, Takashi Iwai (tiwai at suse.de) wrote:
> 
> > > - And snd_pcm_rewind() might return a value that is higher than was
> > >   passed in, which as far as I understood should never happen:
> > > 
> > >   http://mailman.alsa-project.org/pipermail/alsa-devel/2008-April/007308.html
> > > 
> > > These two issues might be caused by the same error.
> > > 
> > > Takashi, Jaroslav, how can I bribe you into fixing this? I'd love to
> > > release my new PulseAudio version soon which heavily relies on
> > > snd_pcm_rewind(), but unfortunately the most important driver (hda
> > > with softvol) makes the most problems with it. :-(
> > 
> > As mentioned earlier, the softvol itself is a simple plain plugin and
> > it has no code to do forward/rewind in itself.  Thus, if a bug is
> > present in softvol, it must be in the generic plugin code -- or there
> > can be a missing piece that the generic code doesn't cover.  I'm not
> > sure yet, as I didn't write that code.
> > 
> > The second problem, the bigger return size, looks like a thinko in the
> > code.  Try the patch below.
> 
> I just posted three patches that fix those issues for me. Please have
> a look. They do basically what your patch does as well, plus fixing
> the return issue.
> 
> The patches are trivial, look correct to me and fix the issues.
> 
> Please merge,

Committed now.  Thanks.


Takashi