masterthread.cpp Example File

/****************************************************************************
**
** Copyright (C) 2012 Denis Shienkov <denis.shienkov@gmail.com>
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtSerialPort module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of The Qt Company Ltd nor the names of its
**     contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "masterthread.h"
#include <QtSerialPort/QSerialPort>
#include <QTime>
QT_USE_NAMESPACE
MasterThread::MasterThread(QObject *parent)
    : QThread(parent), waitTimeout(0), quit(false)
{
}
MasterThread::~MasterThread()
{
    mutex.lock();
    quit = true;
    cond.wakeOne();
    mutex.unlock();
    wait();
}
void MasterThread::transaction(const QString &portName, int waitTimeout, const QString &request)
{
    QMutexLocker locker(&mutex);
    this->portName = portName;
    this->waitTimeout = waitTimeout;
    this->request = request;
    if (!isRunning())
        start();
    else
        cond.wakeOne();
}
void MasterThread::run()
{
    bool currentPortNameChanged = false;
    mutex.lock();
    QString currentPortName;
    if (currentPortName != portName) {
        currentPortName = portName;
        currentPortNameChanged = true;
    }
    int currentWaitTimeout = waitTimeout;
    QString currentRequest = request;
    mutex.unlock();
    QSerialPort serial;
    if (currentPortName.isEmpty()) {
        emit error(tr("No port name specified"));
        return;
    }
    while (!quit) {
        if (currentPortNameChanged) {
            serial.close();
            serial.setPortName(currentPortName);
            if (!serial.open(QIODevice::ReadWrite)) {
                emit error(tr("Can't open %1, error code %2")
                           .arg(portName).arg(serial.error()));
                return;
            }
        }
        // write request
        QByteArray requestData = currentRequest.toLocal8Bit();
        serial.write(requestData);
        if (serial.waitForBytesWritten(waitTimeout)) {
            // read response
            if (serial.waitForReadyRead(currentWaitTimeout)) {
                QByteArray responseData = serial.readAll();
                while (serial.waitForReadyRead(10))
                    responseData += serial.readAll();
                QString response(responseData);
                emit this->response(response);
            } else {
                emit timeout(tr("Wait read response timeout %1")
                             .arg(QTime::currentTime().toString()));
            }
        } else {
            emit timeout(tr("Wait write request timeout %1")
                         .arg(QTime::currentTime().toString()));
        }
        mutex.lock();
        cond.wait(&mutex);
        if (currentPortName != portName) {
            currentPortName = portName;
            currentPortNameChanged = true;
        } else {
            currentPortNameChanged = false;
        }
        currentWaitTimeout = waitTimeout;
        currentRequest = request;
        mutex.unlock();
    }
}