Ticket #6305: condwait_usage.patch

libs/libmythtv/recorderbase.cpp

@@ -31 +31 @@
       audiodevice("/dev/dsp"), videodevice("/dev/video"), vbidevice("/dev/vbi"),
       vbimode(0), ntsc(true), ntsc_framerate(true), video_frame_rate(29.97),
       m_videoAspect(0), m_videoHeight(0), m_videoWidth(0), curRecording(NULL),
-      request_pause(false), paused(false), nextRingBuffer(NULL), nextRecording(NULL),
-      positionMapType(MARK_GOP_BYFRAME), positionMapLock()
+      request_pause(false), paused(false),
+      nextRingBuffer(NULL), nextRecording(NULL),
+      positionMapType(MARK_GOP_BYFRAME), positionMapLock(),
+      pauseWaitSignal(false), unpauseWaitSignal(false)
 {
     QMutexLocker locker(&avcodeclock);
     avcodec_init(); // init CRC's
@@ -167 +169 @@
     MythTimer t;
     t.start();
 
-    // Qt4 requires a QMutex as a parameter...
-    // not sure if this is the best solution.  Mutex Must be locked before wait.
-    QMutex mutex;
-    mutex.lock();
-
     while (true)
     {
         int wait = timeout - t.elapsed();
@@ -181 +178 @@
         else if (IsPaused())
             return true;
 
-        pauseWait.wait(&mutex, wait);
+        pauseWaitMutex.lock();
+        if (pauseWaitSignal == false)
+            pauseWait.wait(&pauseWaitMutex, wait);
+        pauseWaitSignal = false;
+        pauseWaitMutex.unlock();
     }
 }
 
@@ -198 +199 @@
         if (!paused)
         {
             paused = true;
-            pauseWait.wakeAll();
+            triggerPauseWait();
+
             if (tvrec)
                 tvrec->RecorderPaused();
         }
 
-        // Qt4 requires a QMutex as a parameter...
-        // not sure if this is the best solution.  Mutex Must be locked before wait.
-        QMutex mutex;
-        mutex.lock();
-
-        unpauseWait.wait(&mutex, timeout);
+        unpauseWaitMutex.lock();
+        if (unpauseWaitSignal == false)
+           unpauseWait.wait(&unpauseWaitMutex, timeout);
+        unpauseWaitSignal = false;
+        unpauseWaitMutex.unlock();
     }
     if (!request_pause)
         paused = false;
     return paused;
 }
 
+void RecorderBase::triggerPauseWait(void)
+{
+    pauseWaitMutex.lock();
+    pauseWaitSignal = true;
+    pauseWait.wakeAll();
+    pauseWaitMutex.unlock();
+}
+
+bool RecorderBase::catchPauseWait(unsigned long timeout)
+{
+    bool ret = true;
+
+    pauseWaitMutex.lock();
+    if (pauseWaitSignal == false)
+        ret = pauseWait.wait(&pauseWaitMutex, timeout);
+    pauseWaitSignal = false;
+    pauseWaitMutex.unlock();
+    return ret;
+}
+
+void RecorderBase::triggerUnPauseWait(void)
+{
+    unpauseWaitMutex.lock();
+    unpauseWaitSignal = true;
+    unpauseWait.wakeAll();
+    unpauseWaitMutex.unlock();
+}
+
+bool RecorderBase::catchUnPauseWait(unsigned long timeout)
+{
+    bool ret = true;
+
+    unpauseWaitMutex.lock();
+    if (unpauseWaitSignal == false)
+        ret = unpauseWait.wait(&unpauseWaitMutex, timeout);
+    unpauseWaitSignal = false;
+    unpauseWaitMutex.unlock();
+    return ret;
+}
+
 void RecorderBase::CheckForRingBufferSwitch(void)
 {
     nextRingBufferLock.lock();

libs/libmythtv/recorderbase.h

@@ -252 +252 @@
      */
     void ResolutionChange(uint width, uint height, long long frame);
 
+    void triggerPauseWait(void);
+    bool catchPauseWait(unsigned long timeout = ULONG_MAX);
+
+    void triggerUnPauseWait(void);
+    bool catchUnPauseWait(unsigned long timeout = ULONG_MAX);
+
+
     TVRec         *tvrec;
     RingBuffer    *ringBuffer;
     bool           weMadeBuffer;
@@ -276 +283 @@
     // For handling pausing
     bool           request_pause;
     bool           paused;
-    QWaitCondition pauseWait;
-    QWaitCondition unpauseWait;
 
     // For RingBuffer switching
     QMutex         nextRingBufferLock;
@@ -290 +295 @@
     PosMap         positionMap;
     PosMap         positionMapDelta;
 
+
+  private:
+
+    QWaitCondition pauseWait;
+    QMutex         pauseWaitMutex;
+    bool           pauseWaitSignal;
+
+    QWaitCondition unpauseWait;
+    QMutex         unpauseWaitMutex;
+    bool           unpauseWaitSignal;
 };
 
 #endif