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     3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

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    16 ** GNU Lesser General Public License Usage

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    38 ** $QT_END_LICENSE$

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    40 ****************************************************************************/

    41 

    42 #include "connection.h"

    43 

    44 #include <QtNetwork>

    45 

    46 static const int TransferTimeout = 30 * 1000;

    47 static const int PongTimeout = 60 * 1000;

    48 static const int PingInterval = 5 * 1000;

    49 static const char SeparatorToken = ' ';

    50 

    51 Connection::Connection(QObject *parent)

    52     : QTcpSocket(parent)

    53 {

    54     greetingMessage = tr("undefined");

    55     username = tr("unknown");

    56     state = WaitingForGreeting;

    57     currentDataType = Undefined;

    58     numBytesForCurrentDataType = -1;

    59     transferTimerId = 0;

    60     isGreetingMessageSent = false;

    61     pingTimer.setInterval(PingInterval);

    62 

    63     QObject::connect(this, SIGNAL(readyRead()), this, SLOT(processReadyRead()));

    64     QObject::connect(this, SIGNAL(disconnected()), &pingTimer, SLOT(stop()));

    65     QObject::connect(&pingTimer, SIGNAL(timeout()), this, SLOT(sendPing()));

    66     QObject::connect(this, SIGNAL(connected()),

    67                      this, SLOT(sendGreetingMessage()));

    68 }

    69 

    70 QString Connection::name() const

    71 {

    72     return username;

    73 }

    74 

    75 void Connection::setGreetingMessage(const QString &message)

    76 {

    77     greetingMessage = message;

    78 }

    79 

    80 bool Connection::sendMessage(const QString &message)

    81 {

    82     if (message.isEmpty())

    83         return false;

    84 

    85     QByteArray msg = message.toUtf8();

    86     QByteArray data = "MESSAGE " + QByteArray::number(msg.size()) + " " + msg;

    87     return write(data) == data.size();

    88 }

    89 

    90 void Connection::timerEvent(QTimerEvent *timerEvent)

    91 {

    92     if (timerEvent->timerId() == transferTimerId) {

    93         abort();

    94         killTimer(transferTimerId);

    95         transferTimerId = 0;

    96     }

    97 }

    98 

    99 void Connection::processReadyRead()

   100 {

   101     if (state == WaitingForGreeting) {

   102         if (!readProtocolHeader())

   103             return;

   104         if (currentDataType != Greeting) {

   105             abort();

   106             return;

   107         }

   108         state = ReadingGreeting;

   109     }

   110 

   111     if (state == ReadingGreeting) {

   112         if (!hasEnoughData())

   113             return;

   114 

   115         buffer = read(numBytesForCurrentDataType);

   116         if (buffer.size() != numBytesForCurrentDataType) {

   117             abort();

   118             return;

   119         }

   120 

   121         username = QString(buffer) + "@" + peerAddress().toString() + ":"

   122                    + QString::number(peerPort());

   123         currentDataType = Undefined;

   124         numBytesForCurrentDataType = 0;

   125         buffer.clear();

   126 

   127         if (!isValid()) {

   128             abort();

   129             return;

   130         }

   131 

   132         if (!isGreetingMessageSent)

   133             sendGreetingMessage();

   134 

   135         pingTimer.start();

   136         pongTime.start();

   137         state = ReadyForUse;

   138         emit readyForUse();

   139     }

   140 

   141     do {

   142         if (currentDataType == Undefined) {

   143             if (!readProtocolHeader())

   144                 return;

   145         }

   146         if (!hasEnoughData())

   147             return;

   148         processData();

   149     } while (bytesAvailable() > 0);

   150 }

   151 

   152 void Connection::sendPing()

   153 {

   154     if (pongTime.elapsed() > PongTimeout) {

   155         abort();

   156         return;

   157     }

   158 

   159     write("PING 1 p");

   160 }

   161 

   162 void Connection::sendGreetingMessage()

   163 {

   164     QByteArray greeting = greetingMessage.toUtf8();

   165     QByteArray data = "GREETING " + QByteArray::number(greeting.size()) + " " + greeting;

   166     if (write(data) == data.size())

   167         isGreetingMessageSent = true;

   168 }

   169 

   170 int Connection::readDataIntoBuffer(int maxSize)

   171 {

   172     if (maxSize > MaxBufferSize)

   173         return 0;

   174 

   175     int numBytesBeforeRead = buffer.size();

   176     if (numBytesBeforeRead == MaxBufferSize) {

   177         abort();

   178         return 0;

   179     }

   180 

   181     while (bytesAvailable() > 0 && buffer.size() < maxSize) {

   182         buffer.append(read(1));

   183         if (buffer.endsWith(SeparatorToken))

   184             break;

   185     }

   186     return buffer.size() - numBytesBeforeRead;

   187 }

   188 

   189 int Connection::dataLengthForCurrentDataType()

   190 {

   191     if (bytesAvailable() <= 0 || readDataIntoBuffer() <= 0

   192             || !buffer.endsWith(SeparatorToken))

   193         return 0;

   194 

   195     buffer.chop(1);

   196     int number = buffer.toInt();

   197     buffer.clear();

   198     return number;

   199 }

   200 

   201 bool Connection::readProtocolHeader()

   202 {

   203     if (transferTimerId) {

   204         killTimer(transferTimerId);

   205         transferTimerId = 0;

   206     }

   207 

   208     if (readDataIntoBuffer() <= 0) {

   209         transferTimerId = startTimer(TransferTimeout);

   210         return false;

   211     }

   212 

   213     if (buffer == "PING ") {

   214         currentDataType = Ping;

   215     } else if (buffer == "PONG ") {

   216         currentDataType = Pong;

   217     } else if (buffer == "MESSAGE ") {

   218         currentDataType = PlainText;

   219     } else if (buffer == "GREETING ") {

   220         currentDataType = Greeting;

   221     } else {

   222         currentDataType = Undefined;

   223         abort();

   224         return false;

   225     }

   226 

   227     buffer.clear();

   228     numBytesForCurrentDataType = dataLengthForCurrentDataType();

   229     return true;

   230 }

   231 

   232 bool Connection::hasEnoughData()

   233 {

   234     if (transferTimerId) {

   235         QObject::killTimer(transferTimerId);

   236         transferTimerId = 0;

   237     }

   238 

   239     if (numBytesForCurrentDataType <= 0)

   240         numBytesForCurrentDataType = dataLengthForCurrentDataType();

   241 

   242     if (bytesAvailable() < numBytesForCurrentDataType

   243             || numBytesForCurrentDataType <= 0) {

   244         transferTimerId = startTimer(TransferTimeout);

   245         return false;

   246     }

   247 

   248     return true;

   249 }

   250 

   251 void Connection::processData()

   252 {

   253     buffer = read(numBytesForCurrentDataType);

   254     if (buffer.size() != numBytesForCurrentDataType) {

   255         abort();

   256         return;

   257     }

   258 

   259     switch (currentDataType) {

   260     case PlainText:

   261         emit newMessage(username, QString::fromUtf8(buffer));

   262         break;

   263     case Ping:

   264         write("PONG 1 p");

   265         break;

   266     case Pong:

   267         pongTime.restart();

   268         break;

   269     default:

   270         break;

   271     }

   272 

   273     currentDataType = Undefined;

   274     numBytesForCurrentDataType = 0;

   275     buffer.clear();

   276 }