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;
          }

          QDataStream in(&socket);
          in.setVersion(QDataStream::Qt_4_0);
          QString fortune;

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

              in.startTransaction();
              in >> fortune;
          } while (!in.commitTransaction());

          mutex.lock();
          emit newFortune(fortune);

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