qtcpserver.cpp

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//#define QTCPSERVER_DEBUG

#include "private/qobject_p.h"
#include "qalgorithms.h"
#include "qhostaddress.h"
#include "qlist.h"
#include "qpointer.h"
#include "qabstractsocketengine_p.h"
#include "qtcpserver.h"
#include "qtcpsocket.h"
#include "qnetworkproxy.h"

QT_BEGIN_NAMESPACE

#define Q_CHECK_SOCKETENGINE(returnValue) do { \
    if (!d->socketEngine) { \
        return returnValue; \
    } } while (0)

class QTcpServerPrivate : public QObjectPrivate, public QAbstractSocketEngineReceiver
{
    Q_DECLARE_PUBLIC(QTcpServer)
public:
    QTcpServerPrivate();
    ~QTcpServerPrivate();

    QList<QTcpSocket *> pendingConnections;

    quint16 port;
    QHostAddress address;

    QAbstractSocket::SocketState state;
    QAbstractSocketEngine *socketEngine;

    QAbstractSocket::SocketError serverSocketError;
    QString serverSocketErrorString;

    int maxConnections;

#ifndef QT_NO_NETWORKPROXY
    QNetworkProxy proxy;
    QNetworkProxy resolveProxy(const QHostAddress &address, quint16 port);
#endif

    // from QAbstractSocketEngineReceiver
    void readNotification();
    inline void writeNotification() {}
    inline void exceptionNotification() {}
    inline void connectionNotification() {}
#ifndef QT_NO_NETWORKPROXY
    inline void proxyAuthenticationRequired(const QNetworkProxy &, QAuthenticator *) {}
#endif

};

QTcpServerPrivate::QTcpServerPrivate()
 : port(0)
 , state(QAbstractSocket::UnconnectedState)
 , socketEngine(0)
 , serverSocketError(QAbstractSocket::UnknownSocketError)
 , maxConnections(30)
{
}

QTcpServerPrivate::~QTcpServerPrivate()
{
}

#ifndef QT_NO_NETWORKPROXY

QNetworkProxy QTcpServerPrivate::resolveProxy(const QHostAddress &address, quint16 port)
{
    if (address == QHostAddress::LocalHost ||
        address == QHostAddress::LocalHostIPv6)
        return QNetworkProxy::NoProxy;

    QList<QNetworkProxy> proxies;
    if (proxy.type() != QNetworkProxy::DefaultProxy) {
        // a non-default proxy was set with setProxy
        proxies << proxy;
    } else {
        // try the application settings instead
        QNetworkProxyQuery query(port, QString(), QNetworkProxyQuery::TcpServer);
        proxies = QNetworkProxyFactory::proxyForQuery(query);
    }

    // return the first that we can use
    foreach (const QNetworkProxy &p, proxies) {
        if (p.capabilities() & QNetworkProxy::ListeningCapability)
            return p;
    }

    // no proxy found
    // DefaultProxy will raise an error
    return QNetworkProxy(QNetworkProxy::DefaultProxy);
}
#endif

void QTcpServerPrivate::readNotification()
{
    Q_Q(QTcpServer);
    for (;;) {
        if (pendingConnections.count() >= maxConnections) {
#if defined (QTCPSERVER_DEBUG)
            qDebug("QTcpServerPrivate::_q_processIncomingConnection() too many connections");
#endif
            if (socketEngine->isReadNotificationEnabled())
                socketEngine->setReadNotificationEnabled(false);
            return;
        }

        int descriptor = socketEngine->accept();
        if (descriptor == -1)
            break;
#if defined (QTCPSERVER_DEBUG)
        qDebug("QTcpServerPrivate::_q_processIncomingConnection() accepted socket %i", descriptor);
#endif
        q->incomingConnection(descriptor);

        QPointer<QTcpServer> that = q;
        emit q->newConnection();
        if (!that || !q->isListening())
            return;
    }
}

QTcpServer::QTcpServer(QObject *parent)
    : QObject(*new QTcpServerPrivate, parent)
{
}

QTcpServer::~QTcpServer()
{
    close();
}

bool QTcpServer::listen(const QHostAddress &address, quint16 port)
{
    Q_D(QTcpServer);
    if (d->state == QAbstractSocket::ListeningState) {
        qWarning("QTcpServer::listen() called when already listening");
        return false;
    }

    QAbstractSocket::NetworkLayerProtocol proto = address.protocol();

#ifdef QT_NO_NETWORKPROXY
    static const QNetworkProxy &proxy = *(QNetworkProxy *)0;
#else
    QNetworkProxy proxy = d->resolveProxy(address, port);
#endif

    delete d->socketEngine;
    d->socketEngine = QAbstractSocketEngine::createSocketEngine(QAbstractSocket::TcpSocket, proxy, this);
    if (!d->socketEngine) {
        d->serverSocketError = QAbstractSocket::UnsupportedSocketOperationError;
        d->serverSocketErrorString = tr("Operation on socket is not supported");
        return false;
    }
#ifndef QT_NO_BEARERMANAGEMENT
    //copy network session down to the socket engine (if it has been set)
    d->socketEngine->setProperty("_q_networksession", property("_q_networksession"));
#endif
    if (!d->socketEngine->initialize(QAbstractSocket::TcpSocket, proto)) {
        d->serverSocketError = d->socketEngine->error();
        d->serverSocketErrorString = d->socketEngine->errorString();
        return false;
    }

#if defined(Q_OS_UNIX)
    // Under Unix, we want to be able to bind to the port, even if a socket on
    // the same address-port is in TIME_WAIT. Under Windows this is possible
    // anyway -- furthermore, the meaning of reusable on Windows is different:
    // it means that you can use the same address-port for multiple listening
    // sockets.
    // Don't abort though if we can't set that option. For example the socks
    // engine doesn't support that option, but that shouldn't prevent us from
    // trying to bind/listen.
    d->socketEngine->setOption(QAbstractSocketEngine::AddressReusable, 1);
#endif

    if (!d->socketEngine->bind(address, port)) {
        d->serverSocketError = d->socketEngine->error();
        d->serverSocketErrorString = d->socketEngine->errorString();
        return false;
    }

    if (!d->socketEngine->listen()) {
        d->serverSocketError = d->socketEngine->error();
        d->serverSocketErrorString = d->socketEngine->errorString();
        return false;
    }

    d->socketEngine->setReceiver(d);
    d->socketEngine->setReadNotificationEnabled(true);

    d->state = QAbstractSocket::ListeningState;
    d->address = d->socketEngine->localAddress();
    d->port = d->socketEngine->localPort();

#if defined (QTCPSERVER_DEBUG)
    qDebug("QTcpServer::listen(%i, \"%s\") == true (listening on port %i)", port,
           address.toString().toLatin1().constData(), d->socketEngine->localPort());
#endif
    return true;
}

bool QTcpServer::isListening() const
{
    Q_D(const QTcpServer);
    Q_CHECK_SOCKETENGINE(false);
    return d->socketEngine->state() == QAbstractSocket::ListeningState;
}

void QTcpServer::close()
{
    Q_D(QTcpServer);

    qDeleteAll(d->pendingConnections);
    d->pendingConnections.clear();

    if (d->socketEngine) {
        d->socketEngine->close();
        QT_TRY {
            d->socketEngine->deleteLater();
        } QT_CATCH(const std::bad_alloc &) {
            // in out of memory situations, the socketEngine
            // will be deleted in ~QTcpServer (it's a child-object of this)
        }
        d->socketEngine = 0;
    }

    d->state = QAbstractSocket::UnconnectedState;
}

int QTcpServer::socketDescriptor() const
{
    Q_D(const QTcpServer);
    Q_CHECK_SOCKETENGINE(-1);
    return d->socketEngine->socketDescriptor();
}

bool QTcpServer::setSocketDescriptor(int socketDescriptor)
{
    Q_D(QTcpServer);
    if (isListening()) {
        qWarning("QTcpServer::setSocketDescriptor() called when already listening");
        return false;
    }

    if (d->socketEngine)
        delete d->socketEngine;
    d->socketEngine = QAbstractSocketEngine::createSocketEngine(socketDescriptor, this);
    if (!d->socketEngine) {
        d->serverSocketError = QAbstractSocket::UnsupportedSocketOperationError;
        d->serverSocketErrorString = tr("Operation on socket is not supported");
        return false;
    }
#ifndef QT_NO_BEARERMANAGEMENT
    //copy network session down to the socket engine (if it has been set)
    d->socketEngine->setProperty("_q_networksession", property("_q_networksession"));
#endif
    if (!d->socketEngine->initialize(socketDescriptor, QAbstractSocket::ListeningState)) {
        d->serverSocketError = d->socketEngine->error();
        d->serverSocketErrorString = d->socketEngine->errorString();
#if defined (QTCPSERVER_DEBUG)
        qDebug("QTcpServer::setSocketDescriptor(%i) failed (%s)", socketDescriptor,
               d->serverSocketErrorString.toLatin1().constData());
#endif
        return false;
    }

    d->socketEngine->setReceiver(d);
    d->socketEngine->setReadNotificationEnabled(true);

    d->state = d->socketEngine->state();
    d->address = d->socketEngine->localAddress();
    d->port = d->socketEngine->localPort();

#if defined (QTCPSERVER_DEBUG)
    qDebug("QTcpServer::setSocketDescriptor(%i) succeeded.", socketDescriptor);
#endif
    return true;
}

quint16 QTcpServer::serverPort() const
{
    Q_D(const QTcpServer);
    Q_CHECK_SOCKETENGINE(0);
    return d->socketEngine->localPort();
}

QHostAddress QTcpServer::serverAddress() const
{
    Q_D(const QTcpServer);
    Q_CHECK_SOCKETENGINE(QHostAddress(QHostAddress::Null));
    return d->socketEngine->localAddress();
}

bool QTcpServer::waitForNewConnection(int msec, bool *timedOut)
{
    Q_D(QTcpServer);
    if (d->state != QAbstractSocket::ListeningState)
        return false;

    if (!d->socketEngine->waitForRead(msec, timedOut)) {
        d->serverSocketError = d->socketEngine->error();
        d->serverSocketErrorString = d->socketEngine->errorString();
        return false;
    }

    if (timedOut && *timedOut)
        return false;

    d->readNotification();

    return true;
}

bool QTcpServer::hasPendingConnections() const
{
    return !d_func()->pendingConnections.isEmpty();
}

QTcpSocket *QTcpServer::nextPendingConnection()
{
    Q_D(QTcpServer);
    if (d->pendingConnections.isEmpty())
        return 0;

    if (!d->socketEngine->isReadNotificationEnabled())
        d->socketEngine->setReadNotificationEnabled(true);

    return d->pendingConnections.takeFirst();
}

void QTcpServer::incomingConnection(int socketDescriptor)
{
#if defined (QTCPSERVER_DEBUG)
    qDebug("QTcpServer::incomingConnection(%i)", socketDescriptor);
#endif

    QTcpSocket *socket = new QTcpSocket(this);
    socket->setSocketDescriptor(socketDescriptor);
    addPendingConnection(socket);
}

void QTcpServer::addPendingConnection(QTcpSocket* socket)
{
    d_func()->pendingConnections.append(socket);
}

void QTcpServer::setMaxPendingConnections(int numConnections)
{
    d_func()->maxConnections = numConnections;
}

int QTcpServer::maxPendingConnections() const
{
    return d_func()->maxConnections;
}

QAbstractSocket::SocketError QTcpServer::serverError() const
{
    return d_func()->serverSocketError;
}

QString QTcpServer::errorString() const
{
    return d_func()->serverSocketErrorString;
}

#ifndef QT_NO_NETWORKPROXY

void QTcpServer::setProxy(const QNetworkProxy &networkProxy)
{
    Q_D(QTcpServer);
    d->proxy = networkProxy;
}

QNetworkProxy QTcpServer::proxy() const
{
    Q_D(const QTcpServer);
    return d->proxy;
}
#endif // QT_NO_NETWORKPROXY

QT_END_NAMESPACE

#include "moc_qtcpserver.cpp"