Lock the various stream context to prevent racing conditions.

SeekReset was called in player thread, which would reset the av streams, while sometimes in the middle of usage in the decoder thread. Fixes #11705
MythTV · Jul 25, 2013 · 7e7a78c · 7e7a78c
1 parent cf6f6b4
commit 7e7a78c
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Showing 2 changed files with 9 additions and 2 deletions.
diff --git a/mythtv/libs/libmythtv/avformatdecoder.cpp b/mythtv/libs/libmythtv/avformatdecoder.cpp
@@ -695,6 +695,8 @@ void AvFormatDecoder::SeekReset(long long newKey, uint skipFrames,
 
     DecoderBase::SeekReset(newKey, skipFrames, doflush, discardFrames);
 
+    QMutexLocker locker(avcodeclock);
+
     if (doflush)
     {
         lastapts = 0;
@@ -871,8 +873,8 @@ extern "C" void HandleStreamChange(void *data)
         QString("streams_changed 0x%1 -- stream count %2")
             .arg((uint64_t)data,0,16).arg(cnt));
 
-    QMutexLocker locker(avcodeclock);
     decoder->SeekReset(0, 0, true, true);
+    QMutexLocker locker(avcodeclock);
     decoder->ScanStreams(false);
 }
 
@@ -887,8 +889,8 @@ extern "C" void HandleDVDStreamChange(void *data)
         QString("streams_changed 0x%1 -- stream count %2")
             .arg((uint64_t)data,0,16).arg(cnt));
 
-    QMutexLocker locker(avcodeclock);
     //decoder->SeekReset(0, 0, true, true);
+    QMutexLocker locker(avcodeclock);
     decoder->ScanStreams(true);
 }
 
@@ -4661,6 +4663,7 @@ bool AvFormatDecoder::GetFrame(DecodeType decodetype)
             }
 
             int retval = 0;
+            avcodeclock->lock();
             if (!ic || ((retval = ReadPacket(ic, pkt, storevideoframes)) < 0))
             {
                 if (retval == -EAGAIN)
@@ -4670,8 +4673,10 @@ bool AvFormatDecoder::GetFrame(DecodeType decodetype)
                 delete pkt;
                 errno = -retval;
                 LOG(VB_GENERAL, LOG_ERR, QString("decoding error") + ENO);
+                avcodeclock->unlock();
                 return false;
             }
+            avcodeclock->unlock();
 
             if (waitingForChange && pkt->pos >= readAdjust)
                 FileChanged();

diff --git a/mythtv/libs/libmythtv/nuppeldecoder.cpp b/mythtv/libs/libmythtv/nuppeldecoder.cpp
@@ -1385,6 +1385,8 @@ void NuppelDecoder::SeekReset(long long newKey, uint skipFrames,
             .arg((doFlush) ? "do" : "don't")
             .arg((discardFrames) ? "do" : "don't"));
 
+    QMutexLocker locker(avcodeclock);
+
     DecoderBase::SeekReset(newKey, skipFrames, doFlush, discardFrames);
 
     if (mpa_vidcodec && doFlush)