slavethread.cpp Example File

  /****************************************************************************
  **
  ** Copyright (C) 2012 Denis Shienkov <denis.shienkov@gmail.com>
  ** Contact: https://www.qt.io/licensing/
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  ** This file is part of the QtSerialPort module of the Qt Toolkit.
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  #include "slavethread.h"

  #include <QSerialPort>
  #include <QTime>

  SlaveThread::SlaveThread(QObject *parent) :
      QThread(parent)
  {
  }

  SlaveThread::~SlaveThread()
  {
      m_mutex.lock();
      m_quit = true;
      m_mutex.unlock();
      wait();
  }

  void SlaveThread::startSlave(const QString &portName, int waitTimeout, const QString &response)
  {
      const QMutexLocker locker(&m_mutex);
      m_portName = portName;
      m_waitTimeout = waitTimeout;
      m_response = response;
      if (!isRunning())
          start();
  }

  void SlaveThread::run()
  {
      bool currentPortNameChanged = false;

      m_mutex.lock();
      QString currentPortName;
      if (currentPortName != m_portName) {
          currentPortName = m_portName;
          currentPortNameChanged = true;
      }

      int currentWaitTimeout = m_waitTimeout;
      QString currentRespone = m_response;
      m_mutex.unlock();
      QSerialPort serial;

      while (!m_quit) {
          if (currentPortNameChanged) {
              serial.close();
              serial.setPortName(currentPortName);

              if (!serial.open(QIODevice::ReadWrite)) {
                  emit error(tr("Can't open %1, error code %2")
                             .arg(m_portName).arg(serial.error()));
                  return;
              }
          }

          if (serial.waitForReadyRead(currentWaitTimeout)) {
              // read request
              QByteArray requestData = serial.readAll();
              while (serial.waitForReadyRead(10))
                  requestData += serial.readAll();
              // write response
              const QByteArray responseData = currentRespone.toUtf8();
              serial.write(responseData);
              if (serial.waitForBytesWritten(m_waitTimeout)) {
                  const QString request = QString::fromUtf8(requestData);
                  emit this->request(request);
              } else {
                  emit timeout(tr("Wait write response timeout %1")
                               .arg(QTime::currentTime().toString()));
              }
          } else {
              emit timeout(tr("Wait read request timeout %1")
                           .arg(QTime::currentTime().toString()));
          }
          m_mutex.lock();
          if (currentPortName != m_portName) {
              currentPortName = m_portName;
              currentPortNameChanged = true;
          } else {
              currentPortNameChanged = false;
          }
          currentWaitTimeout = m_waitTimeout;
          currentRespone = m_response;
          m_mutex.unlock();
      }
  }