Qt Reference Documentation

# fortunethread.cpp Example File

network/blockingfortuneclient/fortunethread.cpp

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     #include <QtNetwork>

     #include "fortunethread.h"

     FortuneThread::FortuneThread(QObject *parent)
         : QThread(parent), quit(false)
     {
     }

     FortuneThread::~FortuneThread()
     {
         mutex.lock();
         quit = true;
         cond.wakeOne();
         mutex.unlock();
         wait();
     }

     void FortuneThread::requestNewFortune(const QString &hostName, quint16 port)
     {
         QMutexLocker locker(&mutex);
         this->hostName = hostName;
         this->port = port;
         if (!isRunning())
             start();
         else
             cond.wakeOne();
     }

     void FortuneThread::run()
     {
         mutex.lock();
         QString serverName = hostName;
         quint16 serverPort = port;
         mutex.unlock();

         while (!quit) {
             const int Timeout = 5 * 1000;

             QTcpSocket socket;
             socket.connectToHost(serverName, serverPort);

             if (!socket.waitForConnected(Timeout)) {
                 emit error(socket.error(), socket.errorString());
                 return;
             }

             while (socket.bytesAvailable() < (int)sizeof(quint16)) {
                 if (!socket.waitForReadyRead(Timeout)) {
                     emit error(socket.error(), socket.errorString());
                     return;
                 }
             }

             quint16 blockSize;
             QDataStream in(&socket);
             in.setVersion(QDataStream::Qt_4_0);
             in >> blockSize;

             while (socket.bytesAvailable() < blockSize) {
                 if (!socket.waitForReadyRead(Timeout)) {
                     emit error(socket.error(), socket.errorString());
                     return;
                 }
             }

             mutex.lock();
             QString fortune;
             in >> fortune;
             emit newFortune(fortune);

             cond.wait(&mutex);
             serverName = hostName;
             serverPort = port;
             mutex.unlock();
         }
     }