fortunethread.cpp Example File

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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();
     }
 }