Loopback QTcpServer and QTcpSocket : QTcpServer « Qt « C++






Loopback QTcpServer and QTcpSocket

  
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#ifndef DIALOG_H
#define DIALOG_H

#include <QDialog>
#include <QTcpServer>
#include <QTcpSocket>

QT_BEGIN_NAMESPACE
class QDialogButtonBox;
class QLabel;
class QProgressBar;
class QPushButton;
class QTcpServer;
class QTcpSocket;
QT_END_NAMESPACE

class Dialog : public QDialog
{
    Q_OBJECT

public:
    Dialog(QWidget *parent = 0);

public slots:
    void start();
    void acceptConnection();
    void startTransfer();
    void updateServerProgress();
    void updateClientProgress(qint64 numBytes);
    void displayError(QAbstractSocket::SocketError socketError);

private:
    QProgressBar *clientProgressBar;
    QProgressBar *serverProgressBar;
    QLabel *clientStatusLabel;
    QLabel *serverStatusLabel;
    QPushButton *startButton;
    QPushButton *quitButton;
    QDialogButtonBox *buttonBox;

    QTcpServer tcpServer;
    QTcpSocket tcpClient;
    QTcpSocket *tcpServerConnection;
    int bytesToWrite;
    int bytesWritten;
    int bytesReceived;
};

#endif





#include <QtGui>
#include <QtNetwork>

#include "dialog.h"

#if !defined(Q_OS_WINCE)
static const int TotalBytes = 50 * 1024 * 1024;
#else
static const int TotalBytes = 5 * 1024 * 1024;
#endif
static const int PayloadSize = 65536;

Dialog::Dialog(QWidget *parent)
    : QDialog(parent)
{
    clientProgressBar = new QProgressBar;
    clientStatusLabel = new QLabel(tr("Client ready"));
    serverProgressBar = new QProgressBar;
    serverStatusLabel = new QLabel(tr("Server ready"));

    startButton = new QPushButton(tr("&Start"));
    quitButton = new QPushButton(tr("&Quit"));

    buttonBox = new QDialogButtonBox;
    buttonBox->addButton(startButton, QDialogButtonBox::ActionRole);
    buttonBox->addButton(quitButton, QDialogButtonBox::RejectRole);

    connect(startButton, SIGNAL(clicked()), this, SLOT(start()));
    connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));
    connect(&tcpServer, SIGNAL(newConnection()),
            this, SLOT(acceptConnection()));
    connect(&tcpClient, SIGNAL(connected()), this, SLOT(startTransfer()));
    connect(&tcpClient, SIGNAL(bytesWritten(qint64)),
            this, SLOT(updateClientProgress(qint64)));
    connect(&tcpClient, SIGNAL(error(QAbstractSocket::SocketError)),
            this, SLOT(displayError(QAbstractSocket::SocketError)));

    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(clientProgressBar);
    mainLayout->addWidget(clientStatusLabel);
    mainLayout->addWidget(serverProgressBar);
    mainLayout->addWidget(serverStatusLabel);
    mainLayout->addStretch(1);
    mainLayout->addSpacing(10);
    mainLayout->addWidget(buttonBox);
    setLayout(mainLayout);

    setWindowTitle(tr("Loopback"));
}

void Dialog::start()
{
    startButton->setEnabled(false);

#ifndef QT_NO_CURSOR
    QApplication::setOverrideCursor(Qt::WaitCursor);
#endif

    bytesWritten = 0;
    bytesReceived = 0;

    while (!tcpServer.isListening() && !tcpServer.listen()) {
        QMessageBox::StandardButton ret = QMessageBox::critical(this,
                                        tr("Loopback"),
                                        tr("Unable to start the test: %1.")
          .arg(tcpServer.errorString()),
                                        QMessageBox::Retry
          | QMessageBox::Cancel);
        if (ret == QMessageBox::Cancel)
            return;
    }

    serverStatusLabel->setText(tr("Listening"));
    clientStatusLabel->setText(tr("Connecting"));
    tcpClient.connectToHost(QHostAddress::LocalHost, tcpServer.serverPort());
}

void Dialog::acceptConnection()
{
    tcpServerConnection = tcpServer.nextPendingConnection();
    connect(tcpServerConnection, SIGNAL(readyRead()),
            this, SLOT(updateServerProgress()));
    connect(tcpServerConnection, SIGNAL(error(QAbstractSocket::SocketError)),
            this, SLOT(displayError(QAbstractSocket::SocketError)));

    serverStatusLabel->setText(tr("Accepted connection"));
    tcpServer.close();
}

void Dialog::startTransfer()
{
    bytesToWrite = TotalBytes - (int)tcpClient.write(QByteArray(PayloadSize, '@'));
    clientStatusLabel->setText(tr("Connected"));
}

void Dialog::updateServerProgress()
{
    bytesReceived += (int)tcpServerConnection->bytesAvailable();
    tcpServerConnection->readAll();

    serverProgressBar->setMaximum(TotalBytes);
    serverProgressBar->setValue(bytesReceived);
    serverStatusLabel->setText(tr("Received %1MB")
                               .arg(bytesReceived / (1024 * 1024)));

    if (bytesReceived == TotalBytes) {
        tcpServerConnection->close();
        startButton->setEnabled(true);
#ifndef QT_NO_CURSOR
        QApplication::restoreOverrideCursor();
#endif
    }
}

void Dialog::updateClientProgress(qint64 numBytes)
{
    bytesWritten += (int)numBytes;
    if (bytesToWrite > 0)
        bytesToWrite -= (int)tcpClient.write(QByteArray(qMin(bytesToWrite, PayloadSize), '@'));

    clientProgressBar->setMaximum(TotalBytes);
    clientProgressBar->setValue(bytesWritten);
    clientStatusLabel->setText(tr("Sent %1MB")
                               .arg(bytesWritten / (1024 * 1024)));
}

void Dialog::displayError(QAbstractSocket::SocketError socketError)
{
    if (socketError == QTcpSocket::RemoteHostClosedError)
        return;

    QMessageBox::information(this, tr("Network error"),
                             tr("The following error occurred: %1.")
                             .arg(tcpClient.errorString()));

    tcpClient.close();
    tcpServer.close();
    clientProgressBar->reset();
    serverProgressBar->reset();
    clientStatusLabel->setText(tr("Client ready"));
    serverStatusLabel->setText(tr("Server ready"));
    startButton->setEnabled(true);
#ifndef QT_NO_CURSOR
    QApplication::restoreOverrideCursor();
#endif
}





#include <QApplication>

#include "dialog.h"

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    Dialog dialog;
    dialog.show();
    return dialog.exec();
}

   
    
  








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