[mythtv] DVB alpha-0.4

Kenneth Aafloy ke-aa at frisurf.no
Sun Sep 7 08:14:18 EDT 2003


Hi to you too!

Mike Wilcox wrote:

> I seem to have hit a problem that, if I understand correctly, has the 
> same symptoms of a wrong "use_ts" setting - I get zero-length 

The use_ts should be fine as long as the card supports it.

>     DVB#0 Poll timed out waiting for frontend device, retrying.
>     <snip between 4 and 10 more of these...>

I've removed this message now, as it's pretty useless
(and was only for testing).

> I decided to add some debugging into dvbrecorder.cpp to see what was 
> happening with the PIDs and the use_ts parameter (I didn't trust that 
> I'd set these correctly, and the debates on the mailing list left me a 
> little, er, bemused.

He, i'm a horrible coder, sorry!

> ++  //pthread_mutex_unlock(&dvbchannel->lock);

No wonder it wasn't working, it's not even initialized in dvbchannel.
Strange though, that it has worked for me and others :)

> I can't see anything else that's trying to do a mutex on 
> dvbchannel->lock, but then I can't see where dvbchannel-> lock is 
> declared either. Is this mutex shared with other channels in some way? 
> Anything I can do to track down where the lock is actually held?

IIRC, there is something in dvbsections.

>     o some segv's after recording completes (not gdb enabled at the
>     moment though).

DVBCam & DVBSections is pretty ugly coded, and reported fucking with most
things when they are actually not used (no cam in use) :)

>     o failure to display correctly if a channel changes something about
>     the stream while recording is taking place. I don't know exactly
>     what, but I've seen it twice related to the start or end of the ITV
>     news programmes (and still have one recorded).

Hmmm, didn't quite get that!

>     o occasional lockup on changing live-tv channels. particularly from
>     a qam_64 channel to qam_16 channel.

This is also caused by cam & section stuff.

>     o occasional lockup when seeking forward or back in a recorded.

Discussed in earlier threads, i'm trying to track down what is happening,
but no luck yet, feel free to give it a shoot..

> but I'm not so worried about these until I know the effect I'm having by 
> losing the mutex.

I'll try to take my eyes off the telly for a few minutes and fix it :)

> I've also seen one backend log message that referred to "DVB #54", 
> logging something related to CAM , when stopping a recording. Sorry - 
> lost the details though!

Probably also caused by stray pointers in dvbsection.

Delete the dvbcam* dvbsection* files, and remove all reference to
them in dvbrecorder* as suggested a few posts back.

Thanks for reporting this Mike, I'll get off my lazy butt, and fix it:)

Kenneth


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