|  | Home · All Classes · Main Classes · Grouped Classes · Modules · Functions |

# waitconditions.cpp Example File
threads/waitconditions/waitconditions.cpp

    /****************************************************************************
    **
    ** Copyright (C) 2005-2006 Trolltech ASA. All rights reserved.
    **
    ** This file is part of the example classes of the Qt Toolkit.
    **
    ** Licensees holding valid Qt Preview licenses may use this file in
    ** accordance with the Qt Preview License Agreement provided with the
    ** Software.
    **
    ** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for
    ** information about Qt Commercial License Agreements.
    **
    ** Contact info@trolltech.com if any conditions of this licensing are
    ** not clear to you.
    **
    ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
    ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
    **
    ****************************************************************************/

    #include <QtCore>

    #include <stdio.h>
    #include <stdlib.h>

    const int DataSize = 100000;
    const int BufferSize = 8192;
    char buffer[BufferSize];

    QWaitCondition bufferNotEmpty;
    QWaitCondition bufferNotFull;
    QMutex mutex;
    int numUsedBytes = 0;

    class Producer : public QThread
    {
    public:
        void run();
    };

    void Producer::run()
    {
        qsrand(QTime(0,0,0).secsTo(QTime::currentTime()));

        for (int i = 0; i < DataSize; ++i) {
            mutex.lock();
            if (numUsedBytes == BufferSize)
                bufferNotFull.wait(&mutex);
            mutex.unlock();

            buffer[i % BufferSize] = "ACGT"[(int)qrand() % 4];

            mutex.lock();
            ++numUsedBytes;
            bufferNotEmpty.wakeAll();
            mutex.unlock();
        }
    }

    class Consumer : public QThread
    {
    public:
        void run();
    };

    void Consumer::run()
    {
        for (int i = 0; i < DataSize; ++i) {
            mutex.lock();
            if (numUsedBytes == 0)
                bufferNotEmpty.wait(&mutex);
            mutex.unlock();

            fprintf(stderr, "%c", buffer[i % BufferSize]);

            mutex.lock();
            --numUsedBytes;
            bufferNotFull.wakeAll();
            mutex.unlock();
        }
        fprintf(stderr, "\n");
    }

    int main(int argc, char *argv[])
    {
        QCoreApplication app(argc, argv);
        Producer producer;
        Consumer consumer;
        producer.start();
        consumer.start();
        producer.wait();
        consumer.wait();
        return 0;
    }