avoid stack overflow when no data is available

inc/V4l2DeviceSource.h

@@ -76,7 +76,8 @@ class V4L2DeviceSource: public FramedSource
 		void* thread();
 		static void deliverFrameStub(void* clientData) {((V4L2DeviceSource*) clientData)->deliverFrame();};
 		void deliverFrame();
-		static void incomingPacketHandlerStub(void* clientData, int mask) { ((V4L2DeviceSource*) clientData)->getNextFrame(); };
+		static void incomingPacketHandlerStub(void* clientData, int mask) { ((V4L2DeviceSource*) clientData)->incomingPacketHandler(); };
+		void incomingPacketHandler();
 		int getNextFrame();
 		void processFrame(char * frame, int frameSize, const timeval &ref);
 		void queueFrame(char * frame, int frameSize, const timeval &tv);

src/V4l2DeviceSource.cpp

@@ -175,12 +175,24 @@ void V4L2DeviceSource::deliverFrame()
 		}
 		pthread_mutex_unlock (&m_mutex);
 		
+		if (fFrameSize > 0)
+		{
 			// send Frame to the consumer
 			FramedSource::afterGetting(this);			
 		}
+	}
 }
 	
 // FrameSource callback on read event
+void V4L2DeviceSource::incomingPacketHandler()
+{
+	if (this->getNextFrame() <= 0)
+	{
+		handleClosure(this);
+	}
+}
+
+// read from device
 int V4L2DeviceSource::getNextFrame() 
 {
 	char buffer[m_device->getBufferSize()];	
@@ -191,12 +203,10 @@ int V4L2DeviceSource::getNextFrame()
 	if (frameSize < 0)
 	{
 		LOG(NOTICE) << "V4L2DeviceSource::getNextFrame errno:" << errno << " "  << strerror(errno);		
-		handleClosure(this);
 	}
 	else if (frameSize == 0)
 	{
 		LOG(NOTICE) << "V4L2DeviceSource::getNextFrame no data errno:" << errno << " "  << strerror(errno);		
-		handleClosure(this);
 	}
 	else
 	{