Qt 5.6 | Qt Network | Blocking Fortune Client Example | fortunethread.cpp Example File

Qt 5.6.2 Reference Documentation

# fortunethread.cpp Example File

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();
          }
      }