switch rs232 provider to completly async transfer (#255)

libsrc/leddevice/ProviderRs232.cpp

@@ -13,9 +13,15 @@ ProviderRs232::ProviderRs232(const Json::Value &deviceConfig)
 	: _rs232Port(this)
 	, _blockedForDelay(false)
 	, _stateChanged(true)
+	, _bytesToWrite(0)
+	, _bytesWritten(0)
+	, _frameDropCounter(0)
+	, _lastError(QSerialPort::NoError)
 {
 	setConfig(deviceConfig);
 	connect(&_rs232Port, SIGNAL(error(QSerialPort::SerialPortError)), this, SLOT(error(QSerialPort::SerialPortError)));
+	connect(&_rs232Port, SIGNAL(bytesWritten(qint64)), this, SLOT(bytesWritten(qint64)));
+	connect(&_rs232Port, SIGNAL(readyRead()), this, SLOT(readyRead()));
 }
 
 bool ProviderRs232::setConfig(const Json::Value &deviceConfig)
@@ -28,12 +34,33 @@ bool ProviderRs232::setConfig(const Json::Value &deviceConfig)
 	return true;
 }
 
+void ProviderRs232::bytesWritten(qint64 bytes)
+{
+	_bytesWritten += bytes;
+	if (_bytesWritten >= _bytesToWrite)
+	{
+		_bytesToWrite = 0;
+		_blockedForDelay = false;
+	}
+}
+
+
+void ProviderRs232::readyRead()
+{
+	QByteArray data = _rs232Port.readAll();
+	Debug(_log, "received %d bytes data", data.size());
+}
+
+
 void ProviderRs232::error(QSerialPort::SerialPortError error)
 {
 	if ( error != QSerialPort::NoError )
 	{
-		switch (error)
+		if (_lastError != error)
 		{
+			_lastError = error;
+			switch (error)
+			{
 			case QSerialPort::DeviceNotFoundError:
 				Error(_log, "An error occurred while attempting to open an non-existing device."); break;
 			case QSerialPort::PermissionError:
@@ -43,11 +70,11 @@ void ProviderRs232::error(QSerialPort::SerialPortError error)
 			case QSerialPort::NotOpenError:
 				Error(_log, "This error occurs when an operation is executed that can only be successfully performed if the device is open."); break;
 			case QSerialPort::ParityError:
-				Error(_log, "Parity error detected by the hardware while reading data. This value is obsolete. We strongly advise against using it in new code."); break;
+				Error(_log, "Parity error detected by the hardware while reading data."); break;
 			case QSerialPort::FramingError:
-				Error(_log, "Framing error detected by the hardware while reading data. This value is obsolete. We strongly advise against using it in new code."); break;
+				Error(_log, "Framing error detected by the hardware while reading data."); break;
 			case QSerialPort::BreakConditionError:
-				Error(_log, "Break condition detected by the hardware on the input line. This value is obsolete. We strongly advise against using it in new code."); break;
+				Error(_log, "Break condition detected by the hardware on the input line."); break;
 			case QSerialPort::WriteError:
 				Error(_log, "An I/O error occurred while writing the data."); break;
 			case QSerialPort::ReadError:
@@ -59,8 +86,10 @@ void ProviderRs232::error(QSerialPort::SerialPortError error)
 			case QSerialPort::TimeoutError:
 				Error(_log, "A timeout error occurred."); break;
 			default: Error(_log,"An unidentified error occurred. (%d)", error);
+			}
+			_rs232Port.clearError();
+			closeDevice();
 		}
-		_rs232Port.clearError();
 	}
 }
 
@@ -84,15 +113,15 @@ int ProviderRs232::open()
 	Info(_log, "Opening UART: %s", _deviceName.c_str());
 	_rs232Port.setPortName(_deviceName.c_str());
 
-	return tryOpen() ? 0 : -1;
+	return tryOpen(_delayAfterConnect_ms) ? 0 : -1;
 }
 
 
-bool ProviderRs232::tryOpen()
+bool ProviderRs232::tryOpen(const int delayAfterConnect_ms)
 {
 	if ( ! _rs232Port.isOpen() )
 	{
-		if ( ! _rs232Port.open(QIODevice::WriteOnly) )
+		if ( ! _rs232Port.open(QIODevice::ReadWrite) )
 		{
 			if ( _stateChanged )
 			{
@@ -105,46 +134,52 @@ bool ProviderRs232::tryOpen()
 		_stateChanged = true;
 	}
 
-	if (_delayAfterConnect_ms > 0)
+	if (delayAfterConnect_ms > 0)
 	{
 		_blockedForDelay = true;
-		QTimer::singleShot(_delayAfterConnect_ms, this, SLOT(unblockAfterDelay()));
+		QTimer::singleShot(delayAfterConnect_ms, this, SLOT(unblockAfterDelay()));
-		Debug(_log, "Device blocked for %d ms", _delayAfterConnect_ms);
+		Debug(_log, "Device blocked for %d ms", delayAfterConnect_ms);
 	}
 
 	return _rs232Port.isOpen();
 }
 
 
-int ProviderRs232::writeBytes(const unsigned size, const uint8_t * data)
+int ProviderRs232::writeBytes(const qint64 size, const uint8_t * data)
 {
-	if (_blockedForDelay)
+	if (! _blockedForDelay)
 	{
-		return 0;
+		if (!_rs232Port.isOpen())
-	}
+		{
+			return tryOpen(3000) ? 0 : -1;
+		}
 
-	if (!_rs232Port.isOpen())
+		if (_frameDropCounter > 0)
+		{
+			Debug(_log, "%d frames dropped", _frameDropCounter);
+		}
+		_frameDropCounter = 0;
+		_blockedForDelay = true;
+		_bytesToWrite = size;
+		qint64 bytesWritten = _rs232Port.write(reinterpret_cast<const char*>(data), size);
+		if (bytesWritten == -1 || bytesWritten != size)
+		{
+			Warning(_log,"failed writing data");
+			QTimer::singleShot(500, this, SLOT(unblockAfterDelay()));
+			return -1;
+		}
+		QTimer::singleShot(5000, this, SLOT(unblockAfterDelay()));
+	}
+	else
 	{
-		_delayAfterConnect_ms = 3000;
+		_frameDropCounter++;
-		return tryOpen() ? 0 : -1;
 	}
 
-	_rs232Port.flush();
-	qint64 result = _rs232Port.write(reinterpret_cast<const char*>(data), size);
-	if ( result < 0  || result != size)
-	{
-		return -1;
-	}
-	
-	Debug(_log, "write %d ", result);
-	_rs232Port.flush();
-
 	return 0;
 }
 
 
 void ProviderRs232::unblockAfterDelay()
 {
-	Debug(_log, "Device unblocked");
 	_blockedForDelay = false;
 }

libsrc/leddevice/ProviderRs232.h

@@ -49,7 +49,7 @@ protected:
 	 *
 	 * @return Zero on succes else negative
 	 */
-	int writeBytes(const unsigned size, const uint8_t *data);
+	int writeBytes(const qint64 size, const uint8_t *data);
 
 	void closeDevice();
 
@@ -57,10 +57,12 @@ private slots:
 	/// Unblock the device after a connection delay
 	void unblockAfterDelay();
 	void error(QSerialPort::SerialPortError error);
+	void bytesWritten(qint64 bytes);
+	void readyRead();
 
 private:
 	// tries to open device if not opened
-	bool tryOpen();
+	bool tryOpen(const int delayAfterConnect_ms);
 	
 	/// The name of the output device
 	std::string _deviceName;
@@ -77,4 +79,9 @@ private:
 	bool _blockedForDelay;
 	
 	bool _stateChanged;
+
+	qint64 _bytesToWrite;
+	qint64 _bytesWritten;
+	qint64 _frameDropCounter;
+	QSerialPort::SerialPortError _lastError;
 };