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++ // Copyright (C) 2017 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
++
++ #include <QtWidgets>
++ #include <QtNetwork>
++
++ #include "receiver.h"
++
++ Receiver::Receiver(QWidget *parent)
++ : QDialog(parent),
++ groupAddress4(QStringLiteral("239.255.43.21")),
++ groupAddress6(QStringLiteral("ff12::2115"))
++ {
++ statusLabel = new QLabel(tr("Listening for multicast messages on both IPv4 and IPv6"));
++ auto quitButton = new QPushButton(tr("&Quit"));
++
++ auto buttonLayout = new QHBoxLayout;
++ buttonLayout->addStretch(1);
++ buttonLayout->addWidget(quitButton);
++ buttonLayout->addStretch(1);
++
++ auto mainLayout = new QVBoxLayout;
++ mainLayout->addWidget(statusLabel);
++ mainLayout->addLayout(buttonLayout);
++ setLayout(mainLayout);
++
++ setWindowTitle(tr("Multicast Receiver"));
++
++ udpSocket4.bind(QHostAddress::AnyIPv4, 45454, QUdpSocket::ShareAddress);
++ udpSocket4.joinMulticastGroup(groupAddress4);
++
++ if (!udpSocket6.bind(QHostAddress::AnyIPv6, 45454, QUdpSocket::ShareAddress) ||
++ !udpSocket6.joinMulticastGroup(groupAddress6))
++ statusLabel->setText(tr("Listening for multicast messages on IPv4 only"));
++
++ connect(&udpSocket4, &QUdpSocket::readyRead,
++ this, &Receiver::processPendingDatagrams);
++ connect(&udpSocket6, &QUdpSocket::readyRead,
++ this, &Receiver::processPendingDatagrams);
++ connect(quitButton, &QPushButton::clicked,
++ qApp, &QCoreApplication::quit);
++ }
++
++ void Receiver::processPendingDatagrams()
++ {
++ QByteArray datagram;
++
++ // using QUdpSocket::readDatagram (API since Qt 4)
++ while (udpSocket4.hasPendingDatagrams()) {
++ datagram.resize(qsizetype(udpSocket4.pendingDatagramSize()));
++ udpSocket4.readDatagram(datagram.data(), datagram.size());
++ statusLabel->setText(tr("Received IPv4 datagram: \"%1\"")
++ .arg(datagram.constData()));
++ }
++
++ // using QUdpSocket::receiveDatagram (API since Qt 5.8)
++ while (udpSocket6.hasPendingDatagrams()) {
++ QNetworkDatagram dgram = udpSocket6.receiveDatagram();
++ statusLabel->setText(statusLabel->text() +
++ tr("\nReceived IPv6 datagram from [%2]:%3: \"%1\"")
++ .arg(dgram.data().constData(), dgram.senderAddress().toString())
++ .arg(dgram.senderPort()));
++ }
++ }