Qt 5.9 | Qt Core | Local Fortune Server Example | server.cpp Example File

Qt 5.9.9 Reference Documentation

# server.cpp Example File

ipc/localfortuneserver/server.cpp

      /****************************************************************************
      **
      ** Copyright (C) 2016 The Qt Company Ltd.
      ** Contact: https://www.qt.io/licensing/
      **
      ** This file is part of the examples of the Qt Toolkit.
      **
      ** $QT_BEGIN_LICENSE:BSD$
      ** Commercial License Usage
      ** Licensees holding valid commercial Qt licenses may use this file in
      ** accordance with the commercial license agreement provided with the
      ** Software or, alternatively, in accordance with the terms contained in
      ** a written agreement between you and The Qt Company. For licensing terms
      ** and conditions see https://www.qt.io/terms-conditions. For further
      ** information use the contact form at https://www.qt.io/contact-us.
      **
      ** BSD License Usage
      ** Alternatively, you may use this file under the terms of the BSD license
      ** as follows:
      **
      ** "Redistribution and use in source and binary forms, with or without
      ** modification, are permitted provided that the following conditions are
      ** met:
      **   * Redistributions of source code must retain the above copyright
      **     notice, this list of conditions and the following disclaimer.
      **   * Redistributions in binary form must reproduce the above copyright
      **     notice, this list of conditions and the following disclaimer in
      **     the documentation and/or other materials provided with the
      **     distribution.
      **   * Neither the name of The Qt Company Ltd nor the names of its
      **     contributors may be used to endorse or promote products derived
      **     from this software without specific prior written permission.
      **
      **
      ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
      ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
      ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
      ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
      ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
      ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
      ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
      ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
      ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
      ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
      **
      ** $QT_END_LICENSE$
      **
      ****************************************************************************/

      #include <QtWidgets>
      #include <QtNetwork>

      #include <stdlib.h>

      #include "server.h"
      #include <qlocalserver.h>
      #include <qlocalsocket.h>

      Server::Server(QWidget *parent)
          : QDialog(parent)
      {
          statusLabel = new QLabel;
          statusLabel->setWordWrap(true);
          quitButton = new QPushButton(tr("Quit"));
          quitButton->setAutoDefault(false);

          server = new QLocalServer(this);
          if (!server->listen("fortune")) {
              QMessageBox::critical(this, tr("Fortune Server"),
                                    tr("Unable to start the server: %1.")
                                    .arg(server->errorString()));
              close();
              return;
          }

          statusLabel->setText(tr("The server is running.\n"
                                  "Run the Fortune Client example now."));

          fortunes << tr("You've been leading a dog's life. Stay off the furniture.")
                   << tr("You've got to think about tomorrow.")
                   << tr("You will be surprised by a loud noise.")
                   << tr("You will feel hungry again in another hour.")
                   << tr("You might have mail.")
                   << tr("You cannot kill time without injuring eternity.")
                   << tr("Computers are not intelligent. They only think they are.");

          connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));
          connect(server, SIGNAL(newConnection()), this, SLOT(sendFortune()));

          QHBoxLayout *buttonLayout = new QHBoxLayout;
          buttonLayout->addStretch(1);
          buttonLayout->addWidget(quitButton);
          buttonLayout->addStretch(1);

          QVBoxLayout *mainLayout = new QVBoxLayout;
          mainLayout->addWidget(statusLabel);
          mainLayout->addLayout(buttonLayout);
          setLayout(mainLayout);

          setWindowTitle(tr("Fortune Server"));
      }

      void Server::sendFortune()
      {
          QByteArray block;
          QDataStream out(&block, QIODevice::WriteOnly);
          out.setVersion(QDataStream::Qt_4_0);
          out << (quint32)0;
          out << fortunes.at(qrand() % fortunes.size());
          out.device()->seek(0);
          out << (quint32)(block.size() - sizeof(quint32));

          QLocalSocket *clientConnection = server->nextPendingConnection();
          connect(clientConnection, SIGNAL(disconnected()),
                  clientConnection, SLOT(deleteLater()));

          clientConnection->write(block);
          clientConnection->flush();
          clientConnection->disconnectFromServer();
      }