| /**************************************************************************** |
| ** |
| ** Copyright (C) 2016 The Qt Company Ltd. |
| ** Copyright (C) 2018 Intel Corporation. |
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| ** This file is part of the examples of the Qt Toolkit. |
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| ****************************************************************************/ |
| |
| #include "connection.h" |
| |
| #include <QtNetwork> |
| |
| static const int TransferTimeout = 30 * 1000; |
| static const int PongTimeout = 60 * 1000; |
| static const int PingInterval = 5 * 1000; |
| |
| /* |
| * Protocol is defined as follows, using the CBOR Data Definition Language: |
| * |
| * protocol = [ |
| * greeting, ; must start with a greeting command |
| * * command ; zero or more regular commands after |
| * ] |
| * command = plaintext / ping / pong / greeting |
| * plaintext = { 0 => text } |
| * ping = { 1 => null } |
| * pong = { 2 => null } |
| * greeting = { 3 => text } |
| */ |
| |
| Connection::Connection(QObject *parent) |
| : QTcpSocket(parent), writer(this) |
| { |
| greetingMessage = tr("undefined"); |
| username = tr("unknown"); |
| state = WaitingForGreeting; |
| currentDataType = Undefined; |
| transferTimerId = -1; |
| isGreetingMessageSent = false; |
| pingTimer.setInterval(PingInterval); |
| |
| QObject::connect(this, SIGNAL(readyRead()), this, SLOT(processReadyRead())); |
| QObject::connect(this, SIGNAL(disconnected()), &pingTimer, SLOT(stop())); |
| QObject::connect(&pingTimer, SIGNAL(timeout()), this, SLOT(sendPing())); |
| QObject::connect(this, SIGNAL(connected()), |
| this, SLOT(sendGreetingMessage())); |
| } |
| |
| Connection::Connection(qintptr socketDescriptor, QObject *parent) |
| : Connection(parent) |
| { |
| setSocketDescriptor(socketDescriptor); |
| reader.setDevice(this); |
| } |
| |
| Connection::~Connection() |
| { |
| if (isGreetingMessageSent) { |
| // Indicate clean shutdown. |
| writer.endArray(); |
| waitForBytesWritten(2000); |
| } |
| } |
| |
| QString Connection::name() const |
| { |
| return username; |
| } |
| |
| void Connection::setGreetingMessage(const QString &message) |
| { |
| greetingMessage = message; |
| } |
| |
| bool Connection::sendMessage(const QString &message) |
| { |
| if (message.isEmpty()) |
| return false; |
| |
| writer.startMap(1); |
| writer.append(PlainText); |
| writer.append(message); |
| writer.endMap(); |
| return true; |
| } |
| |
| void Connection::timerEvent(QTimerEvent *timerEvent) |
| { |
| if (timerEvent->timerId() == transferTimerId) { |
| abort(); |
| killTimer(transferTimerId); |
| transferTimerId = -1; |
| } |
| } |
| |
| void Connection::processReadyRead() |
| { |
| // we've got more data, let's parse |
| reader.reparse(); |
| while (reader.lastError() == QCborError::NoError) { |
| if (state == WaitingForGreeting) { |
| if (!reader.isArray()) |
| break; // protocol error |
| |
| reader.enterContainer(); // we'll be in this array forever |
| state = ReadingGreeting; |
| } else if (reader.containerDepth() == 1) { |
| // Current state: no command read |
| // Next state: read command ID |
| if (!reader.hasNext()) { |
| reader.leaveContainer(); |
| disconnectFromHost(); |
| return; |
| } |
| |
| if (!reader.isMap() || !reader.isLengthKnown() || reader.length() != 1) |
| break; // protocol error |
| reader.enterContainer(); |
| } else if (currentDataType == Undefined) { |
| // Current state: read command ID |
| // Next state: read command payload |
| if (!reader.isInteger()) |
| break; // protocol error |
| currentDataType = DataType(reader.toInteger()); |
| reader.next(); |
| } else { |
| // Current state: read command payload |
| if (reader.isString()) { |
| auto r = reader.readString(); |
| buffer += r.data; |
| if (r.status != QCborStreamReader::EndOfString) |
| continue; |
| } else if (reader.isNull()) { |
| reader.next(); |
| } else { |
| break; // protocol error |
| } |
| |
| // Next state: no command read |
| reader.leaveContainer(); |
| if (transferTimerId != -1) { |
| killTimer(transferTimerId); |
| transferTimerId = -1; |
| } |
| |
| if (state == ReadingGreeting) { |
| if (currentDataType != Greeting) |
| break; // protocol error |
| processGreeting(); |
| } else { |
| processData(); |
| } |
| } |
| } |
| |
| if (reader.lastError() != QCborError::EndOfFile) |
| abort(); // parse error |
| |
| if (transferTimerId != -1 && reader.containerDepth() > 1) |
| transferTimerId = startTimer(TransferTimeout); |
| } |
| |
| void Connection::sendPing() |
| { |
| if (pongTime.elapsed() > PongTimeout) { |
| abort(); |
| return; |
| } |
| |
| writer.startMap(1); |
| writer.append(Ping); |
| writer.append(nullptr); // no payload |
| writer.endMap(); |
| } |
| |
| void Connection::sendGreetingMessage() |
| { |
| writer.startArray(); // this array never ends |
| |
| writer.startMap(1); |
| writer.append(Greeting); |
| writer.append(greetingMessage); |
| writer.endMap(); |
| isGreetingMessageSent = true; |
| |
| if (!reader.device()) |
| reader.setDevice(this); |
| } |
| |
| void Connection::processGreeting() |
| { |
| username = buffer + '@' + peerAddress().toString() + ':' |
| + QString::number(peerPort()); |
| currentDataType = Undefined; |
| buffer.clear(); |
| |
| if (!isValid()) { |
| abort(); |
| return; |
| } |
| |
| if (!isGreetingMessageSent) |
| sendGreetingMessage(); |
| |
| pingTimer.start(); |
| pongTime.start(); |
| state = ReadyForUse; |
| emit readyForUse(); |
| } |
| |
| void Connection::processData() |
| { |
| switch (currentDataType) { |
| case PlainText: |
| emit newMessage(username, buffer); |
| break; |
| case Ping: |
| writer.startMap(1); |
| writer.append(Pong); |
| writer.append(nullptr); // no payload |
| writer.endMap(); |
| break; |
| case Pong: |
| pongTime.restart(); |
| break; |
| default: |
| break; |
| } |
| |
| currentDataType = Undefined; |
| buffer.clear(); |
| } |