server.cpp Example File

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  #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 << (quint16)0;
      out << fortunes.at(qrand() % fortunes.size());
      out.device()->seek(0);
      out << (quint16)(block.size() - sizeof(quint16));

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

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