[mythtv-commits] Ticket #10668: mythtranscode segfault [patch]

[MythTV]

#10668: mythtranscode segfault [patch]
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 Reporter:  adiemus <mythtv@…>       |           Type:  Bug Report - Crash
   Status:  new                      |       Priority:  minor
Milestone:  unknown                  |      Component:  MythTV -
  Version:  0.25-fixes               |  Mythtranscode
 Keywords:  mythtranscode crash      |       Severity:  medium
  segfault                           |  Ticket locked:  0
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 I recently upgraded my 0.21-fixed myth environment to 0.25-fixes.  I'm
 chasing down several problems, once of which is that my newly transcoded
 content looks terrible (it's very blocky and seems to frequently corrupt a
 bit on scene changes) and that mythtranscode refuses to respect the
 sampling rate I set for audio transcode.

 Anyway, in trying to troubleshoot these issues by running mythtranscode
 manually, I ran into an immediate and easily reproducible segfault.
 (Command, output and backtrace attached)

 The source of the crash is ultimately at dtvrecorder.cpp:35 in the LOC
 preprocessor macro which dereferences tvrec without verifying that it's
 not NULL.  (In the case of a transcode, it's explicitly NULL, leading to
 the crash in DTVRecorder::ResetForNewFile())

 I'm far too unfamiliar with myth's codebase to understand the proper way
 to fix the problem, but a simple workaround is to validate tvrec first,
 which seems to at least allow me to run mythtranscode manually so I can
 get about finding the source of my other issues.

 Very simple patch attached.  (Hopefully in a useful format)

-- 
Ticket URL: <http://code.mythtv.org/trac/ticket/10668>
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