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// Copyright (C) 2016 The Qt Company Ltd.
// Copyright (C) 2018 Intel Corporation.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include <QtNetwork>
#include "client.h"
#include "connection.h"
#include "peermanager.h"
static const qint32 BroadcastInterval = 2000;
static const unsigned broadcastPort = 45000;
PeerManager::PeerManager(Client *client)
: QObject(client)
{
this->client = client;
static const char *envVariables[] = {
"USERNAME", "USER", "USERDOMAIN", "HOSTNAME", "DOMAINNAME"
};
for (const char *varname : envVariables) {
username = qEnvironmentVariable(varname);
if (!username.isNull())
break;
}
if (username.isEmpty())
username = "unknown";
updateAddresses();
serverPort = 0;
broadcastSocket.bind(QHostAddress::Any, broadcastPort, QUdpSocket::ShareAddress
| QUdpSocket::ReuseAddressHint);
connect(&broadcastSocket, &QUdpSocket::readyRead,
this, &PeerManager::readBroadcastDatagram);
broadcastTimer.setInterval(BroadcastInterval);
connect(&broadcastTimer, &QTimer::timeout,
this, &PeerManager::sendBroadcastDatagram);
}
void PeerManager::setServerPort(int port)
{
serverPort = port;
}
QString PeerManager::userName() const
{
return username;
}
void PeerManager::startBroadcasting()
{
broadcastTimer.start();
}
bool PeerManager::isLocalHostAddress(const QHostAddress &address) const
{
for (const QHostAddress &localAddress : ipAddresses) {
if (address.isEqual(localAddress))
return true;
}
return false;
}
void PeerManager::sendBroadcastDatagram()
{
QByteArray datagram;
{
QCborStreamWriter writer(&datagram);
writer.startArray(2);
writer.append(username);
writer.append(serverPort);
writer.endArray();
}
bool validBroadcastAddresses = true;
for (const QHostAddress &address : qAsConst(broadcastAddresses)) {
if (broadcastSocket.writeDatagram(datagram, address,
broadcastPort) == -1)
validBroadcastAddresses = false;
}
if (!validBroadcastAddresses)
updateAddresses();
}
void PeerManager::readBroadcastDatagram()
{
while (broadcastSocket.hasPendingDatagrams()) {
QHostAddress senderIp;
quint16 senderPort;
QByteArray datagram;
datagram.resize(broadcastSocket.pendingDatagramSize());
if (broadcastSocket.readDatagram(datagram.data(), datagram.size(),
&senderIp, &senderPort) == -1)
continue;
int senderServerPort;
{
// decode the datagram
QCborStreamReader reader(datagram);
if (reader.lastError() != QCborError::NoError || !reader.isArray())
continue;
if (!reader.isLengthKnown() || reader.length() != 2)
continue;
reader.enterContainer();
if (reader.lastError() != QCborError::NoError || !reader.isString())
continue;
while (reader.readString().status == QCborStreamReader::Ok) {
// we don't actually need the username right now
}
if (reader.lastError() != QCborError::NoError || !reader.isUnsignedInteger())
continue;
senderServerPort = reader.toInteger();
}
if (isLocalHostAddress(senderIp) && senderServerPort == serverPort)
continue;
if (!client->hasConnection(senderIp)) {
Connection *connection = new Connection(this);
emit newConnection(connection);
connection->connectToHost(senderIp, senderServerPort);
}
}
}
void PeerManager::updateAddresses()
{
broadcastAddresses.clear();
ipAddresses.clear();
const QList<QNetworkInterface> interfaces = QNetworkInterface::allInterfaces();
for (const QNetworkInterface &interface : interfaces) {
const QList<QNetworkAddressEntry> entries = interface.addressEntries();
for (const QNetworkAddressEntry &entry : entries) {
QHostAddress broadcastAddress = entry.broadcast();
if (broadcastAddress != QHostAddress::Null && entry.ip() != QHostAddress::LocalHost) {
broadcastAddresses << broadcastAddress;
ipAddresses << entry.ip();
}
}
}
}
|
