Fixed startup initialization sequence: interim state #1

include/dsp/samplesink.h

@@ -15,7 +15,8 @@ public:
 	virtual void feed(SampleVector::const_iterator begin, SampleVector::const_iterator end, bool positiveOnly) = 0;
 	virtual void start() = 0;
 	virtual void stop() = 0;
-	virtual bool handleMessage(Message* cmd) = 0;
+	virtual bool handleMessage(Message* cmd) = 0; //!< Handle message immediately or submit it to a queue
+	virtual bool executeMessage(Message* cmd);    //!< Handle message immediately FIXME: shall we keep it or fix behaviour of ThreadedSampleSink?
 };
 
 #endif // INCLUDE_SAMPLESINK_H

include/dsp/threadedsamplesink.h

@@ -23,6 +23,7 @@ public:
 	void start();
 	void stop();
 	bool handleMessage(Message* cmd);
+	virtual bool executeMessage(Message* cmd);
 
 protected:
 	QMutex m_mutex;

include/util/messagequeue.h

@@ -19,6 +19,7 @@ public:
 	Message* accept();
 
 	int countPending();
+	void clear();
 
 signals:
 	void messageEnqueued();