[mythtv-commits] Ticket #2822: Fix a segfault in livetv when switching from a digital to an analog channel

[MythTV]

#2822: Fix a segfault in livetv when switching from a digital to an analog channel
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 Reporter:  jedynamic at bellsouth.net  |       Owner:  ijr    
     Type:  patch                    |      Status:  new    
 Priority:  minor                    |   Milestone:  unknown
Component:  mythtv                   |     Version:  head   
 Severity:  low                      |  
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 The problem is that when switching from a digital to an analog channel in
 livetv a segfault can occur.  I ran this through gdb and noticed that the
 av_pause_frame.buf somehow became NULL when we where displaying the pause
 frame. This caused the segfault.

 I looked through the code and noticed that the av_pause_frame.buf will
 always get cleared out when InputChanged() is called (via a call to
 DeleteBuffers()).  The only way the pause frame will get recreated is if
 CreateBuffers() is called (which ends up calling CreatePauseFrame()).
 CreateBuffers() is only called if we didn't change a codec_id (inside
 InputChanged()).  If the codec_id changes then we call InitSetupBuffers().
 InitSetupBuffers() will not recreate the av_pause_frame.buf.  Thus, we get
 the segfault noted above once we try to display a pause frame.

 My patch will make InitSetupBuffers() recreate the pause frame.  I have
 tested a variant of this patch in .20 (only the VideoOutputSubType()
 parameter passed is different) and I do not see the segfault anymore.

 Jimmy

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Ticket URL: <http://svn.mythtv.org/trac/ticket/2822>
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