6 files changed, 178 insertions, 166 deletions

diff --git a/examples/network/network-chat/client.cpp b/examples/network/network-chat/client.cpp
index c1eda52a0c..97c2c44b6b 100644
--- a/examples/network/network-chat/client.cpp
+++ b/examples/network/network-chat/client.cpp
@@ -78,7 +78,7 @@ void Client::sendMessage(const QString &message)
 
 QString Client::nickName() const
 {
-    return QString(peerManager->userName()) + '@' + QHostInfo::localHostName()
+    return peerManager->userName() + '@' + QHostInfo::localHostName()
            + ':' + QString::number(server.serverPort());
 }
 
diff --git a/examples/network/network-chat/connection.cpp b/examples/network/network-chat/connection.cpp
index 332d5dc56b..58cf67eb6d 100644
--- a/examples/network/network-chat/connection.cpp
+++ b/examples/network/network-chat/connection.cpp
@@ -1,6 +1,7 @@
 /****************************************************************************
 **
 ** Copyright (C) 2016 The Qt Company Ltd.
+** Copyright (C) 2018 Intel Corporation.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the examples of the Qt Toolkit.
@@ -55,17 +56,29 @@
 static const int TransferTimeout = 30 * 1000;
 static const int PongTimeout = 60 * 1000;
 static const int PingInterval = 5 * 1000;
-static const char SeparatorToken = ' ';
+
+/*
+ * 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)
+    : QTcpSocket(parent), writer(this)
 {
     greetingMessage = tr("undefined");
     username = tr("unknown");
     state = WaitingForGreeting;
     currentDataType = Undefined;
-    numBytesForCurrentDataType = -1;
-    transferTimerId = 0;
+    transferTimerId = -1;
     isGreetingMessageSent = false;
     pingTimer.setInterval(PingInterval);
 
@@ -76,6 +89,22 @@ Connection::Connection(QObject *parent)
                      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;
@@ -91,9 +120,11 @@ 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();
+    writer.startMap(1);
+    writer.append(PlainText);
+    writer.append(message);
+    writer.endMap();
+    return true;
 }
 
 void Connection::timerEvent(QTimerEvent *timerEvent)
@@ -101,61 +132,75 @@ void Connection::timerEvent(QTimerEvent *timerEvent)
     if (timerEvent->timerId() == transferTimerId) {
         abort();
         killTimer(transferTimerId);
-        transferTimerId = 0;
+        transferTimerId = -1;
     }
 }
 
 void Connection::processReadyRead()
 {
-    if (state == WaitingForGreeting) {
-        if (!readProtocolHeader())
-            return;
-        if (currentDataType != Greeting) {
-            abort();
-            return;
+    // 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();
+            }
         }
-        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();
-    }
+    if (reader.lastError() != QCborError::EndOfFile)
+        abort();       // parse error
 
-    do {
-        if (currentDataType == Undefined) {
-            if (!readProtocolHeader())
-                return;
-        }
-        if (!hasEnoughData())
-            return;
-        processData();
-    } while (bytesAvailable() > 0);
+    if (transferTimerId != -1 && reader.containerDepth() > 1)
+        transferTimerId = startTimer(TransferTimeout);
 }
 
 void Connection::sendPing()
@@ -165,112 +210,58 @@ void Connection::sendPing()
         return;
     }
 
-    write("PING 1 p");
+    writer.startMap(1);
+    writer.append(Ping);
+    writer.append(nullptr);     // no payload
+    writer.endMap();
 }
 
 void Connection::sendGreetingMessage()
 {
-    QByteArray greeting = greetingMessage.toUtf8();
-    QByteArray data = "GREETING " + QByteArray::number(greeting.size()) + ' ' + greeting;
-    if (write(data) == data.size())
-        isGreetingMessageSent = true;
-}
+    writer.startArray();        // this array never ends
 
-int Connection::readDataIntoBuffer(int maxSize)
-{
-    if (maxSize > MaxBufferSize)
-        return 0;
+    writer.startMap(1);
+    writer.append(Greeting);
+    writer.append(greetingMessage);
+    writer.endMap();
+    isGreetingMessageSent = true;
 
-    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;
+    if (!reader.device())
+        reader.setDevice(this);
 }
 
-int Connection::dataLengthForCurrentDataType()
+void Connection::processGreeting()
 {
-    if (bytesAvailable() <= 0 || readDataIntoBuffer() <= 0
-            || !buffer.endsWith(SeparatorToken))
-        return 0;
-
-    buffer.chop(1);
-    int number = buffer.toInt();
+    username = buffer + '@' + peerAddress().toString() + ':'
+            + QString::number(peerPort());
+    currentDataType = Undefined;
     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;
+    if (!isValid()) {
         abort();
-        return false;
-    }
-
-    buffer.clear();
-    numBytesForCurrentDataType = dataLengthForCurrentDataType();
-    return true;
-}
-
-bool Connection::hasEnoughData()
-{
-    if (transferTimerId) {
-        QObject::killTimer(transferTimerId);
-        transferTimerId = 0;
+        return;
     }
 
-    if (numBytesForCurrentDataType <= 0)
-        numBytesForCurrentDataType = dataLengthForCurrentDataType();
-
-    if (bytesAvailable() < numBytesForCurrentDataType
-            || numBytesForCurrentDataType <= 0) {
-        transferTimerId = startTimer(TransferTimeout);
-        return false;
-    }
+    if (!isGreetingMessageSent)
+        sendGreetingMessage();
 
-    return true;
+    pingTimer.start();
+    pongTime.start();
+    state = ReadyForUse;
+    emit readyForUse();
 }
 
 void Connection::processData()
 {
-    buffer = read(numBytesForCurrentDataType);
-    if (buffer.size() != numBytesForCurrentDataType) {
-        abort();
-        return;
-    }
-
     switch (currentDataType) {
     case PlainText:
-        emit newMessage(username, QString::fromUtf8(buffer));
+        emit newMessage(username, buffer);
         break;
     case Ping:
-        write("PONG 1 p");
+        writer.startMap(1);
+        writer.append(Pong);
+        writer.append(nullptr);     // no payload
+        writer.endMap();
         break;
     case Pong:
         pongTime.restart();
@@ -280,6 +271,5 @@ void Connection::processData()
     }
 
     currentDataType = Undefined;
-    numBytesForCurrentDataType = 0;
     buffer.clear();
 }
diff --git a/examples/network/network-chat/connection.h b/examples/network/network-chat/connection.h
index 67d25d4d1e..fa0671a522 100644
--- a/examples/network/network-chat/connection.h
+++ b/examples/network/network-chat/connection.h
@@ -51,10 +51,12 @@
 #ifndef CONNECTION_H
 #define CONNECTION_H
 
+#include <QCborStreamReader>
+#include <QCborStreamWriter>
+#include <QElapsedTimer>
 #include <QHostAddress>
 #include <QString>
 #include <QTcpSocket>
-#include <QTime>
 #include <QTimer>
 
 static const int MaxBufferSize = 1024000;
@@ -78,6 +80,8 @@ public:
     };
 
     Connection(QObject *parent = 0);
+    Connection(qintptr socketDescriptor, QObject *parent = 0);
+    ~Connection();
 
     QString name() const;
     void setGreetingMessage(const QString &message);
@@ -96,20 +100,19 @@ private slots:
     void sendGreetingMessage();
 
 private:
-    int readDataIntoBuffer(int maxSize = MaxBufferSize);
-    int dataLengthForCurrentDataType();
-    bool readProtocolHeader();
     bool hasEnoughData();
+    void processGreeting();
     void processData();
 
+    QCborStreamReader reader;
+    QCborStreamWriter writer;
     QString greetingMessage;
     QString username;
     QTimer pingTimer;
-    QTime pongTime;
-    QByteArray buffer;
+    QElapsedTimer pongTime;
+    QString buffer;
     ConnectionState state;
     DataType currentDataType;
-    int numBytesForCurrentDataType;
     int transferTimerId;
     bool isGreetingMessageSent;
 };
diff --git a/examples/network/network-chat/peermanager.cpp b/examples/network/network-chat/peermanager.cpp
index c70cc5e56d..38fa2e8e50 100644
--- a/examples/network/network-chat/peermanager.cpp
+++ b/examples/network/network-chat/peermanager.cpp
@@ -1,6 +1,7 @@
 /****************************************************************************
 **
 ** Copyright (C) 2016 The Qt Company Ltd.
+** Copyright (C) 2018 Intel Corporation.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the examples of the Qt Toolkit.
@@ -62,16 +63,14 @@ PeerManager::PeerManager(Client *client)
 {
     this->client = client;
 
-    QStringList envVariables;
-    envVariables << "USERNAME" << "USER" << "USERDOMAIN"
-                 << "HOSTNAME" << "DOMAINNAME";
+    static const char *envVariables[] = {
+        "USERNAME", "USER", "USERDOMAIN", "HOSTNAME", "DOMAINNAME"
+    };
 
-    QProcessEnvironment environment = QProcessEnvironment::systemEnvironment();
-    foreach (QString string, envVariables) {
-        if (environment.contains(string)) {
-            username = environment.value(string).toUtf8();
+    for (const char *varname : envVariables) {
+        username = qEnvironmentVariable(varname);
+        if (!username.isNull())
             break;
-        }
     }
 
     if (username.isEmpty())
@@ -95,7 +94,7 @@ void PeerManager::setServerPort(int port)
     serverPort = port;
 }
 
-QByteArray PeerManager::userName() const
+QString PeerManager::userName() const
 {
     return username;
 }
@@ -108,7 +107,7 @@ void PeerManager::startBroadcasting()
 bool PeerManager::isLocalHostAddress(const QHostAddress &address)
 {
     foreach (QHostAddress localAddress, ipAddresses) {
-        if (address == localAddress)
+        if (address.isEqual(localAddress))
             return true;
     }
     return false;
@@ -116,9 +115,14 @@ bool PeerManager::isLocalHostAddress(const QHostAddress &address)
 
 void PeerManager::sendBroadcastDatagram()
 {
-    QByteArray datagram(username);
-    datagram.append('@');
-    datagram.append(QByteArray::number(serverPort));
+    QByteArray datagram;
+    {
+        QCborStreamWriter writer(&datagram);
+        writer.startArray(2);
+        writer.append(username);
+        writer.append(serverPort);
+        writer.endArray();
+    }
 
     bool validBroadcastAddresses = true;
     foreach (QHostAddress address, broadcastAddresses) {
@@ -142,11 +146,27 @@ void PeerManager::readBroadcastDatagram()
                                          &senderIp, &senderPort) == -1)
             continue;
 
-        QList<QByteArray> list = datagram.split('@');
-        if (list.size() != 2)
-            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();
+        }
 
-        int senderServerPort = list.at(1).toInt();
         if (isLocalHostAddress(senderIp) && senderServerPort == serverPort)
             continue;
 
diff --git a/examples/network/network-chat/peermanager.h b/examples/network/network-chat/peermanager.h
index 0bcd67579c..b79028235b 100644
--- a/examples/network/network-chat/peermanager.h
+++ b/examples/network/network-chat/peermanager.h
@@ -68,7 +68,7 @@ public:
     PeerManager(Client *client);
 
     void setServerPort(int port);
-    QByteArray userName() const;
+    QString userName() const;
     void startBroadcasting();
     bool isLocalHostAddress(const QHostAddress &address);
 
@@ -87,7 +87,7 @@ private:
     QList<QHostAddress> ipAddresses;
     QUdpSocket broadcastSocket;
     QTimer broadcastTimer;
-    QByteArray username;
+    QString username;
     int serverPort;
 };
 
diff --git a/examples/network/network-chat/server.cpp b/examples/network/network-chat/server.cpp
index cc154728d5..b3e4a07f60 100644
--- a/examples/network/network-chat/server.cpp
+++ b/examples/network/network-chat/server.cpp
@@ -61,7 +61,6 @@ Server::Server(QObject *parent)
 
 void Server::incomingConnection(qintptr socketDescriptor)
 {
-    Connection *connection = new Connection(this);
-    connection->setSocketDescriptor(socketDescriptor);
+    Connection *connection = new Connection(socketDescriptor, this);
     emit newConnection(connection);
 }