Frontend playback crash/abort

[otto at kolsi dot fi]

I'm seeing fairly frequent and reproducible frontend crash / program abort with trunk head (r27060).

I've attached two backtraces generated with profile build and from the core files.

Below is frontend -v important,general,playback log from the time of the crash:

...
2010-10-31 11:29:07.957 ScreenSaverX11Private: StopTimer
2010-10-31 11:29:07.967 ScreenSaverX11Private: ResetTimer -- end
2010-10-31 11:29:07.971 PID 26505: exited: status=256, result=1
2010-10-31 11:29:07.989 OSD: Base theme size: 1280x720
2010-10-31 11:29:07.989 OSD: Scaling factors: 0.5625x0.8
2010-10-31 11:29:07.999 AO: Opening audio device 'iec958:CARD=ICH5,DEV=0' ch 2(2) sr 48000 sf signed 16 bit reenc 0
2010-10-31 11:29:07.999 Opening ALSA audio device 'iec958:CARD=ICH5,DEV=0'.
2010-10-31 11:29:08.000 AudioPlayer: Enabling Audio
2010-10-31 11:29:08.001 Dec: Selected track #1 in the Unknown language(0)
2010-10-31 11:29:08.001 Dec: Selected track #1 in the Finnish language(6711662)
2010-10-31 11:29:08.001 Dec: Selected track #1 in the Finnish language(6711662)
pure virtual method called
terminate called without an active exception

Version:

$ mythfrontend --version
Please attach all output as a file in bug reports.
MythTV Version   : 27060M
MythTV Branch    : trunk
Network Protocol : 63
Library API      : 0.25.20101028-1
QT Version       : 4.6.3
Options compiled in:
 linux profile silent using_alsa using_pulse using_pulseoutput using_backend using_bindings_perl using_bindings_python using_dvb using_frontend using_libfftw3 using_lirc using_opengl_video using_opengl_vsync using_qtdbus using_qtwebkit using_x11 using_xrandr using_xv using_bindings_perl using_bindings_python using_mythtranscode using_opengl using_ffmpeg_threads

[otto at kolsi dot fi]

Revrting back to r27010 "fixes" the issue.

[beirdo]

At least one of those crashes is teletext-related. I'll hand this to markk, but feel free to punt it elsewhere.

[markk]

(In [27114]) Lock the OSD when the teletext decoder is updating the teletext screen and fix an OSD locking typo.

r27011 removed the code that paused the player/decoder while the OSD is reinitialised (as it can cause lockups in conjunction with the letterbox detection code - and I thought it was safe to do so!). The teletext decoder however updates the teletext screen directly and hence it can crash hard (N.B. the other caption screens do not operate in the same way).

So lock the OSD while the update takes place (which will also reset the teletext viewer).

Closes #9166