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50
51#include "dialog.h"
52
53#include <QtNetwork>
54#include <QtWidgets>
55
56static const int TotalBytes = 50 * 1024 * 1024;
57static const int PayloadSize = 64 * 1024; // 64 KB
58
59Dialog::Dialog(QWidget *parent)
60 : QDialog(parent)
61{
62 clientProgressBar = new QProgressBar;
63 clientStatusLabel = new QLabel(tr("Client ready"));
64 serverProgressBar = new QProgressBar;
65 serverStatusLabel = new QLabel(tr("Server ready"));
66
67 startButton = new QPushButton(tr("&Start"));
68 quitButton = new QPushButton(tr("&Quit"));
69
70 buttonBox = new QDialogButtonBox;
71 buttonBox->addButton(startButton, QDialogButtonBox::ActionRole);
72 buttonBox->addButton(quitButton, QDialogButtonBox::RejectRole);
73
74 connect(startButton, &QAbstractButton::clicked, this, &Dialog::start);
75 connect(quitButton, &QAbstractButton::clicked, this, &QWidget::close);
76 connect(&tcpServer, &QTcpServer::newConnection,
77 this, &Dialog::acceptConnection);
78 connect(&tcpClient, &QAbstractSocket::connected, this, &Dialog::startTransfer);
79 connect(&tcpClient, &QIODevice::bytesWritten,
80 this, &Dialog::updateClientProgress);
81 connect(&tcpClient, &QAbstractSocket::errorOccurred,
82 this, &Dialog::displayError);
83
84 QVBoxLayout *mainLayout = new QVBoxLayout;
85 mainLayout->addWidget(clientProgressBar);
86 mainLayout->addWidget(clientStatusLabel);
87 mainLayout->addWidget(serverProgressBar);
88 mainLayout->addWidget(serverStatusLabel);
89 mainLayout->addStretch(1);
90 mainLayout->addSpacing(10);
91 mainLayout->addWidget(buttonBox);
92 setLayout(mainLayout);
93
94 setWindowTitle(tr("Loopback"));
95}
96
97void Dialog::start()
98{
99 startButton->setEnabled(false);
100
101#ifndef QT_NO_CURSOR
102 QGuiApplication::setOverrideCursor(Qt::WaitCursor);
103#endif
104
105 bytesWritten = 0;
106 bytesReceived = 0;
107
108 while (!tcpServer.isListening() && !tcpServer.listen()) {
109 QMessageBox::StandardButton ret = QMessageBox::critical(this,
110 tr("Loopback"),
111 tr("Unable to start the test: %1.")
112 .arg(tcpServer.errorString()),
113 QMessageBox::Retry
114 | QMessageBox::Cancel);
115 if (ret == QMessageBox::Cancel)
116 return;
117 }
118
119 serverStatusLabel->setText(tr("Listening"));
120 clientStatusLabel->setText(tr("Connecting"));
121 tcpClient.connectToHost(QHostAddress::LocalHost, tcpServer.serverPort());
122}
123
124void Dialog::acceptConnection()
125{
126 tcpServerConnection = tcpServer.nextPendingConnection();
127 if (!tcpServerConnection) {
128 serverStatusLabel->setText(tr("Error: got invalid pending connection!"));
129 return;
130 }
131
132 connect(tcpServerConnection, &QIODevice::readyRead,
133 this, &Dialog::updateServerProgress);
134 connect(tcpServerConnection, &QAbstractSocket::errorOccurred,
135 this, &Dialog::displayError);
136 connect(tcpServerConnection, &QTcpSocket::disconnected,
137 tcpServerConnection, &QTcpSocket::deleteLater);
138
139 serverStatusLabel->setText(tr("Accepted connection"));
140 tcpServer.close();
141}
142
143void Dialog::startTransfer()
144{
145 // called when the TCP client connected to the loopback server
146 bytesToWrite = TotalBytes - int(tcpClient.write(QByteArray(PayloadSize, '@')));
147 clientStatusLabel->setText(tr("Connected"));
148}
149
150void Dialog::updateServerProgress()
151{
152 bytesReceived += int(tcpServerConnection->bytesAvailable());
153 tcpServerConnection->readAll();
154
155 serverProgressBar->setMaximum(TotalBytes);
156 serverProgressBar->setValue(bytesReceived);
157 serverStatusLabel->setText(tr("Received %1MB")
158 .arg(bytesReceived / (1024 * 1024)));
159
160 if (bytesReceived == TotalBytes) {
161 tcpServerConnection->close();
162 startButton->setEnabled(true);
163#ifndef QT_NO_CURSOR
164 QGuiApplication::restoreOverrideCursor();
165#endif
166 }
167}
168
169void Dialog::updateClientProgress(qint64 numBytes)
170{
171 // called when the TCP client has written some bytes
172 bytesWritten += int(numBytes);
173
174 // only write more if not finished and when the Qt write buffer is below a certain size.
175 if (bytesToWrite > 0 && tcpClient.bytesToWrite() <= 4 * PayloadSize)
176 bytesToWrite -= tcpClient.write(QByteArray(qMin(bytesToWrite, PayloadSize), '@'));
177
178 clientProgressBar->setMaximum(TotalBytes);
179 clientProgressBar->setValue(bytesWritten);
180 clientStatusLabel->setText(tr("Sent %1MB").arg(bytesWritten / (1024 * 1024)));
181}
182
183void Dialog::displayError(QAbstractSocket::SocketError socketError)
184{
185 if (socketError == QTcpSocket::RemoteHostClosedError)
186 return;
187
188 QMessageBox::information(this, tr("Network error"),
189 tr("The following error occurred: %1.")
190 .arg(tcpClient.errorString()));
191
192 tcpClient.close();
193 tcpServer.close();
194 clientProgressBar->reset();
195 serverProgressBar->reset();
196 clientStatusLabel->setText(tr("Client ready"));
197 serverStatusLabel->setText(tr("Server ready"));
198 startButton->setEnabled(true);
199#ifndef QT_NO_CURSOR
200 QGuiApplication::restoreOverrideCursor();
201#endif
202}
203