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

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

     /****************************************************************************
     **
     ** Copyright (C) 2005-2008 Trolltech ASA. All rights reserved.
     **
     ** This file is part of the example classes of the Qt Toolkit.
     **
     ** This file may be used under the terms of the GNU General Public
     ** License versions 2.0 or 3.0 as published by the Free Software
     ** Foundation and appearing in the files LICENSE.GPL2 and LICENSE.GPL3
     ** included in the packaging of this file.  Alternatively you may (at
     ** your option) use any later version of the GNU General Public
     ** License if such license has been publicly approved by Trolltech ASA
     ** (or its successors, if any) and the KDE Free Qt Foundation. In
     ** addition, as a special exception, Trolltech gives you certain
     ** additional rights. These rights are described in the Trolltech GPL
     ** Exception version 1.2, which can be found at
     ** http://www.trolltech.com/products/qt/gplexception/ and in the file
     ** GPL_EXCEPTION.txt in this package.
     **
     ** Please review the following information to ensure GNU General
     ** Public Licensing requirements will be met:
     ** http://trolltech.com/products/qt/licenses/licensing/opensource/. If
     ** you are unsure which license is appropriate for your use, please
     ** review the following information:
     ** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
     ** or contact the sales department at sales@trolltech.com.
     **
     ** In addition, as a special exception, Trolltech, as the sole
     ** copyright holder for Qt Designer, grants users of the Qt/Eclipse
     ** Integration plug-in the right for the Qt/Eclipse Integration to
     ** link to functionality provided by Qt Designer and its related
     ** libraries.
     **
     ** This file is provided "AS IS" with NO WARRANTY OF ANY KIND,
     ** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR
     ** A PARTICULAR PURPOSE. Trolltech reserves all rights not expressly
     ** granted herein.
     **
     ** 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;
     }