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Diffstat (limited to 'examples/network/network-chat/connection.cpp')
| -rw-r--r-- | examples/network/network-chat/connection.cpp | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/examples/network/network-chat/connection.cpp b/examples/network/network-chat/connection.cpp new file mode 100644 index 0000000000..9171d1fc5f --- /dev/null +++ b/examples/network/network-chat/connection.cpp @@ -0,0 +1,275 @@ +/**************************************************************************** +** +** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the examples of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:BSD$ +** You may use this file under the terms of the BSD license as follows: +** +** "Redistribution and use in source and binary forms, with or without +** modification, are permitted provided that the following conditions are +** met: +** * Redistributions of source code must retain the above copyright +** notice, this list of conditions and the following disclaimer. +** * Redistributions in binary form must reproduce the above copyright +** notice, this list of conditions and the following disclaimer in +** the documentation and/or other materials provided with the +** distribution. +** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor +** the names of its contributors may be used to endorse or promote +** products derived from this software without specific prior written +** permission. +** +** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "connection.h" + +#include <QtNetwork> + +static const int TransferTimeout = 30 * 1000; +static const int PongTimeout = 60 * 1000; +static const int PingInterval = 5 * 1000; +static const char SeparatorToken = ' '; + +Connection::Connection(QObject *parent) + : QTcpSocket(parent) +{ + greetingMessage = tr("undefined"); + username = tr("unknown"); + state = WaitingForGreeting; + currentDataType = Undefined; + numBytesForCurrentDataType = -1; + transferTimerId = 0; + 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())); +} + +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; + + QByteArray msg = message.toUtf8(); + QByteArray data = "MESSAGE " + QByteArray::number(msg.size()) + ' ' + msg; + return write(data) == data.size(); +} + +void Connection::timerEvent(QTimerEvent *timerEvent) +{ + if (timerEvent->timerId() == transferTimerId) { + abort(); + killTimer(transferTimerId); + transferTimerId = 0; + } +} + +void Connection::processReadyRead() +{ + if (state == WaitingForGreeting) { + if (!readProtocolHeader()) + return; + if (currentDataType != Greeting) { + abort(); + return; + } + state = ReadingGreeting; + } + + if (state == ReadingGreeting) { + if (!hasEnoughData()) + return; + + buffer = read(numBytesForCurrentDataType); + if (buffer.size() != numBytesForCurrentDataType) { + abort(); + return; + } + + username = QString(buffer) + '@' + peerAddress().toString() + ':' + + QString::number(peerPort()); + currentDataType = Undefined; + numBytesForCurrentDataType = 0; + buffer.clear(); + + if (!isValid()) { + abort(); + return; + } + + if (!isGreetingMessageSent) + sendGreetingMessage(); + + pingTimer.start(); + pongTime.start(); + state = ReadyForUse; + emit readyForUse(); + } + + do { + if (currentDataType == Undefined) { + if (!readProtocolHeader()) + return; + } + if (!hasEnoughData()) + return; + processData(); + } while (bytesAvailable() > 0); +} + +void Connection::sendPing() +{ + if (pongTime.elapsed() > PongTimeout) { + abort(); + return; + } + + write("PING 1 p"); +} + +void Connection::sendGreetingMessage() +{ + QByteArray greeting = greetingMessage.toUtf8(); + QByteArray data = "GREETING " + QByteArray::number(greeting.size()) + ' ' + greeting; + if (write(data) == data.size()) + isGreetingMessageSent = true; +} + +int Connection::readDataIntoBuffer(int maxSize) +{ + if (maxSize > MaxBufferSize) + return 0; + + int numBytesBeforeRead = buffer.size(); + if (numBytesBeforeRead == MaxBufferSize) { + abort(); + return 0; + } + + while (bytesAvailable() > 0 && buffer.size() < maxSize) { + buffer.append(read(1)); + if (buffer.endsWith(SeparatorToken)) + break; + } + return buffer.size() - numBytesBeforeRead; +} + +int Connection::dataLengthForCurrentDataType() +{ + if (bytesAvailable() <= 0 || readDataIntoBuffer() <= 0 + || !buffer.endsWith(SeparatorToken)) + return 0; + + buffer.chop(1); + int number = buffer.toInt(); + buffer.clear(); + return number; +} + +bool Connection::readProtocolHeader() +{ + if (transferTimerId) { + killTimer(transferTimerId); + transferTimerId = 0; + } + + if (readDataIntoBuffer() <= 0) { + transferTimerId = startTimer(TransferTimeout); + return false; + } + + if (buffer == "PING ") { + currentDataType = Ping; + } else if (buffer == "PONG ") { + currentDataType = Pong; + } else if (buffer == "MESSAGE ") { + currentDataType = PlainText; + } else if (buffer == "GREETING ") { + currentDataType = Greeting; + } else { + currentDataType = Undefined; + abort(); + return false; + } + + buffer.clear(); + numBytesForCurrentDataType = dataLengthForCurrentDataType(); + return true; +} + +bool Connection::hasEnoughData() +{ + if (transferTimerId) { + QObject::killTimer(transferTimerId); + transferTimerId = 0; + } + + if (numBytesForCurrentDataType <= 0) + numBytesForCurrentDataType = dataLengthForCurrentDataType(); + + if (bytesAvailable() < numBytesForCurrentDataType + || numBytesForCurrentDataType <= 0) { + transferTimerId = startTimer(TransferTimeout); + return false; + } + + return true; +} + +void Connection::processData() +{ + buffer = read(numBytesForCurrentDataType); + if (buffer.size() != numBytesForCurrentDataType) { + abort(); + return; + } + + switch (currentDataType) { + case PlainText: + emit newMessage(username, QString::fromUtf8(buffer)); + break; + case Ping: + write("PONG 1 p"); + break; + case Pong: + pongTime.restart(); + break; + default: + break; + } + + currentDataType = Undefined; + numBytesForCurrentDataType = 0; + buffer.clear(); +} |