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Please review the following information to ** ensure the GNU General Public License version 2.0 requirements will be ** met: http://www.gnu.org/licenses/gpl-2.0.html. ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #ifndef QMODBUSRTUSERIALSLAVE_P_H #define QMODBUSRTUSERIALSLAVE_P_H #include #include #include #include #include #include #include #include #include // // W A R N I N G // ------------- // // This file is not part of the Qt API. It exists purely as an // implementation detail. This header file may change from version to // version without notice, or even be removed. // // We mean it. // QT_BEGIN_NAMESPACE Q_DECLARE_LOGGING_CATEGORY(QT_MODBUS) Q_DECLARE_LOGGING_CATEGORY(QT_MODBUS_LOW) class QModbusRtuSerialSlavePrivate : public QModbusServerPrivate { Q_DECLARE_PUBLIC(QModbusRtuSerialSlave) public: void setupSerialPort() { Q_Q(QModbusRtuSerialSlave); m_serialPort = new QSerialPort(q); QObject::connect(m_serialPort, &QSerialPort::readyRead, q, [this]() { if (m_interFrameTimer.isValid() && m_interFrameTimer.elapsed() > m_interFrameDelayMilliseconds && !m_requestBuffer.isEmpty()) { // This permits response buffer clearing if it contains garbage // but still permits cases where very slow baud rates can cause // chunked and delayed packets qCDebug(QT_MODBUS_LOW) << "(RTU server) Dropping older ADU fragments due to larger than 3.5 char delay (expected:" << m_interFrameDelayMilliseconds << ", max:" << m_interFrameTimer.elapsed() << ")"; m_requestBuffer.clear(); } m_interFrameTimer.start(); const qint64 size = m_serialPort->size(); m_requestBuffer += m_serialPort->read(size); const QModbusSerialAdu adu(QModbusSerialAdu::Rtu, m_requestBuffer); qCDebug(QT_MODBUS_LOW) << "(RTU server) Received ADU:" << adu.rawData().toHex(); // Index -> description // Server address -> 1 byte // FunctionCode -> 1 byte // FunctionCode specific content -> 0-252 bytes // CRC -> 2 bytes Q_Q(QModbusRtuSerialSlave); QModbusCommEvent event = QModbusCommEvent::ReceiveEvent; if (q->value(QModbusServer::ListenOnlyMode).toBool()) event |= QModbusCommEvent::ReceiveFlag::CurrentlyInListenOnlyMode; // We expect at least the server address, function code and CRC. if (adu.rawSize() < 4) { // TODO: LRC should be 3 bytes. qCWarning(QT_MODBUS) << "(RTU server) Incomplete ADU received, ignoring"; // The quantity of CRC errors encountered by the remote device since its last // restart, clear counters operation, or power-up. In case of a message // length < 4 bytes, the receiving device is not able to calculate the CRC. incrementCounter(QModbusServerPrivate::Counter::BusCommunicationError); storeModbusCommEvent(event | QModbusCommEvent::ReceiveFlag::CommunicationError); return; } // Server address is set to 0, this is a broadcast. m_processesBroadcast = (adu.serverAddress() == 0); if (q->processesBroadcast()) event |= QModbusCommEvent::ReceiveFlag::BroadcastReceived; const int pduSizeWithoutFcode = QModbusRequest::calculateDataSize(adu.pdu()); // server address byte + function code byte + PDU size + 2 bytes CRC if ((pduSizeWithoutFcode < 0) || ((2 + pduSizeWithoutFcode + 2) != adu.rawSize())) { qCWarning(QT_MODBUS) << "(RTU server) ADU does not match expected size, ignoring"; // The quantity of messages addressed to the remote device that it could not // handle due to a character overrun condition, since its last restart, clear // counters operation, or power-up. A character overrun is caused by data // characters arriving at the port faster than they can be stored, or by the loss // of a character due to a hardware malfunction. incrementCounter(QModbusServerPrivate::Counter::BusCharacterOverrun); storeModbusCommEvent(event | QModbusCommEvent::ReceiveFlag::CharacterOverrun); return; } // We received the full message, including checksum. We do not expect more bytes to // arrive, so clear the buffer. All new bytes are considered part of the next message. m_requestBuffer.resize(0); if (!adu.matchingChecksum()) { qCWarning(QT_MODBUS) << "(RTU server) Discarding request with wrong CRC, received:" << adu.checksum() << ", calculated CRC:" << QModbusSerialAdu::calculateCRC(adu.data(), adu.size()); // The quantity of CRC errors encountered by the remote device since its last // restart, clear counters operation, or power-up. incrementCounter(QModbusServerPrivate::Counter::BusCommunicationError); storeModbusCommEvent(event | QModbusCommEvent::ReceiveFlag::CommunicationError); return; } // The quantity of messages that the remote device has detected on the communications // system since its last restart, clear counters operation, or power-up. incrementCounter(QModbusServerPrivate::Counter::BusMessage); // If we do not process a Broadcast ... if (!q->processesBroadcast()) { // check if the server address matches ... if (q->serverAddress() != adu.serverAddress()) { // no, not our address! Ignore! qCDebug(QT_MODBUS) << "(RTU server) Wrong server address, expected" << q->serverAddress() << "got" << adu.serverAddress(); return; } } // else { Broadcast -> Server address will never match, deliberately ignore } storeModbusCommEvent(event); // store the final event before processing const QModbusRequest req = adu.pdu(); qCDebug(QT_MODBUS) << "(RTU server) Request PDU:" << req; QModbusResponse response; // If the device ... if (q->value(QModbusServer::DeviceBusy).value() == 0xffff) { // is busy, update the quantity of messages addressed to the remote device for // which it returned a Server Device Busy exception response, since its last // restart, clear counters operation, or power-up. incrementCounter(QModbusServerPrivate::Counter::ServerBusy); response = QModbusExceptionResponse(req.functionCode(), QModbusExceptionResponse::ServerDeviceBusy); } else { // is not busy, update the quantity of messages addressed to the remote device, // or broadcast, that the remote device has processed since its last restart, // clear counters operation, or power-up. incrementCounter(QModbusServerPrivate::Counter::ServerMessage); response = q->processRequest(req); } qCDebug(QT_MODBUS) << "(RTU server) Response PDU:" << response; event = QModbusCommEvent::SentEvent; // reset event after processing if (q->value(QModbusServer::ListenOnlyMode).toBool()) event |= QModbusCommEvent::SendFlag::CurrentlyInListenOnlyMode; if ((!response.isValid()) || q->processesBroadcast() || q->value(QModbusServer::ListenOnlyMode).toBool()) { // The quantity of messages addressed to the remote device for which it has // returned no response (neither a normal response nor an exception response), // since its last restart, clear counters operation, or power-up. incrementCounter(QModbusServerPrivate::Counter::ServerNoResponse); storeModbusCommEvent(event); return; } const QByteArray result = QModbusSerialAdu::create(QModbusSerialAdu::Rtu, q->serverAddress(), response); qCDebug(QT_MODBUS_LOW) << "(RTU server) Response ADU:" << result.toHex(); if (!m_serialPort->isOpen()) { qCDebug(QT_MODBUS) << "(RTU server) Requesting serial port has closed."; q->setError(QModbusRtuSerialSlave::tr("Requesting serial port is closed"), QModbusDevice::WriteError); incrementCounter(QModbusServerPrivate::Counter::ServerNoResponse); storeModbusCommEvent(event); return; } qint64 writtenBytes = m_serialPort->write(result); if ((writtenBytes == -1) || (writtenBytes < result.size())) { qCDebug(QT_MODBUS) << "(RTU server) Cannot write requested response to serial port."; q->setError(QModbusRtuSerialSlave::tr("Could not write response to client"), QModbusDevice::WriteError); incrementCounter(QModbusServerPrivate::Counter::ServerNoResponse); storeModbusCommEvent(event); m_serialPort->clear(QSerialPort::Output); return; } if (response.isException()) { switch (response.exceptionCode()) { case QModbusExceptionResponse::IllegalFunction: case QModbusExceptionResponse::IllegalDataAddress: case QModbusExceptionResponse::IllegalDataValue: event |= QModbusCommEvent::SendFlag::ReadExceptionSent; break; case QModbusExceptionResponse::ServerDeviceFailure: event |= QModbusCommEvent::SendFlag::ServerAbortExceptionSent; break; case QModbusExceptionResponse::ServerDeviceBusy: // The quantity of messages addressed to the remote device for which it // returned a server device busy exception response, since its last restart, // clear counters operation, or power-up. incrementCounter(QModbusServerPrivate::Counter::ServerBusy); event |= QModbusCommEvent::SendFlag::ServerBusyExceptionSent; break; case QModbusExceptionResponse::NegativeAcknowledge: // The quantity of messages addressed to the remote device for which it // returned a negative acknowledge (NAK) exception response, since its last // restart, clear counters operation, or power-up. incrementCounter(QModbusServerPrivate::Counter::ServerNAK); event |= QModbusCommEvent::SendFlag::ServerProgramNAKExceptionSent; break; default: break; } // The quantity of Modbus exception responses returned by the remote device since // its last restart, clear counters operation, or power-up. incrementCounter(QModbusServerPrivate::Counter::BusExceptionError); } else { switch (quint16(req.functionCode())) { case 0x0a: // Poll 484 (not in the official Modbus specification) *1 case 0x0e: // Poll Controller (not in the official Modbus specification) *1 case QModbusRequest::GetCommEventCounter: // fall through and bail out break; default: // The device's event counter is incremented once for each successful message // completion. Do not increment for exception responses, poll commands, or fetch // event counter commands. *1 but mentioned here ^^^ incrementCounter(QModbusServerPrivate::Counter::CommEvent); break; } } storeModbusCommEvent(event); // store the final event after processing }); QObject::connect(m_serialPort, &QSerialPort::errorOccurred, q, [this](QSerialPort::SerialPortError error) { if (error == QSerialPort::NoError) return; qCDebug(QT_MODBUS) << "(RTU server) QSerialPort error:" << error << (m_serialPort ? m_serialPort->errorString() : QString()); Q_Q(QModbusRtuSerialSlave); switch (error) { case QSerialPort::DeviceNotFoundError: q->setError(QModbusDevice::tr("Referenced serial device does not exist."), QModbusDevice::ConnectionError); break; case QSerialPort::PermissionError: q->setError(QModbusDevice::tr("Cannot open serial device due to permissions."), QModbusDevice::ConnectionError); break; case QSerialPort::OpenError: case QSerialPort::NotOpenError: q->setError(QModbusDevice::tr("Cannot open serial device."), QModbusDevice::ConnectionError); break; case QSerialPort::WriteError: q->setError(QModbusDevice::tr("Write error."), QModbusDevice::WriteError); break; case QSerialPort::ReadError: q->setError(QModbusDevice::tr("Read error."), QModbusDevice::ReadError); break; case QSerialPort::ResourceError: q->setError(QModbusDevice::tr("Resource error."), QModbusDevice::ConnectionError); break; case QSerialPort::UnsupportedOperationError: q->setError(QModbusDevice::tr("Device operation is not supported error."), QModbusDevice::ConfigurationError); break; case QSerialPort::TimeoutError: q->setError(QModbusDevice::tr("Timeout error."), QModbusDevice::TimeoutError); break; case QSerialPort::UnknownError: q->setError(QModbusDevice::tr("Unknown error."), QModbusDevice::UnknownError); break; default: qCDebug(QT_MODBUS) << "(RTU server) Unhandled QSerialPort error" << error; break; } }); QObject::connect(m_serialPort, &QSerialPort::aboutToClose, q, [this]() { Q_Q(QModbusRtuSerialSlave); // update state if socket closure was caused by remote side if (q->state() != QModbusDevice::ClosingState) q->setState(QModbusDevice::UnconnectedState); }); } void setupEnvironment() { if (m_serialPort) { m_serialPort->setPortName(m_comPort); m_serialPort->setParity(m_parity); m_serialPort->setBaudRate(m_baudRate); m_serialPort->setDataBits(m_dataBits); m_serialPort->setStopBits(m_stopBits); } // for calculation details see // QModbusRtuSerialMasterPrivate::calculateInterFrameDelay() m_interFrameDelayMilliseconds = qMax(m_interFrameDelayMilliseconds, qCeil(3500. / (qreal(m_baudRate) / 11.))); m_requestBuffer.clear(); } QIODevice *device() const override { return m_serialPort; } QByteArray m_requestBuffer; bool m_processesBroadcast = false; QSerialPort *m_serialPort = nullptr; QElapsedTimer m_interFrameTimer; int m_interFrameDelayMilliseconds = 2; }; QT_END_NAMESPACE #endif // QMODBUSRTUSERIALSLAVE_P_H