[vlc-devel] Mutex Lock problem

[Rémi Denis-Courmont]

   Hello,

On Thursday 03 February 2011, Tommy Tran wrote:
> Since v1.1.0, a few libvlc extern audio-related functions don't work 
> anymore. As of v1.1.17, the issue still exist. To help with debugging, I 
> picked one function that doesn't work (libvlc_audio_get_channel) and  one
> function that does work (libvlc_audio_get_track) and play the same  media
> file and show the callstack and the values of the related  variables.
> 
> I posted the callstacks on the forum:
> http://forum.videolan.org/viewtopic.php?f=32&t=87115
> 
> Anyone got an idea why the owner thread is non-zero for the "GetChannel"
> case?

Because a thread holds the lock, or the mutex is invalid (dangling pointer).

> Is it OK to call EnterCriticalSelection() when there is an owner
> thread?

Yes, although it should be rare.

> Is it possible that some code is calling EnterCriticalSelection()
> and forgot to call LeaveCriticalSelection()?

Maybe.

-- 
Rémi Denis-Courmont
http://www.remlab.info