path: root/src/network/socket/qlocalserver_unix.cpp

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**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtNetwork module of the Qt Toolkit.
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** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
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#include "qlocalserver.h"
#include "qlocalserver_p.h"
#include "qlocalsocket.h"
#include "qlocalsocket_p.h"
#include "qnet_unix_p.h"

#ifndef QT_NO_LOCALSERVER

#include <sys/socket.h>
#include <sys/un.h>

#include <qdebug.h>
#include <qdir.h>
#include <qdatetime.h>

QT_BEGIN_NAMESPACE

void QLocalServerPrivate::init()
{
}

bool QLocalServerPrivate::removeServer(const QString &name)
{
    QString fileName;
    if (name.startsWith(QLatin1Char('/'))) {
        fileName = name;
    } else {
        fileName = QDir::cleanPath(QDir::tempPath());
        fileName += QLatin1Char('/') + name;
    }
    if (QFile::exists(fileName))
        return QFile::remove(fileName);
    else
        return true;
}

bool QLocalServerPrivate::listen(const QString &requestedServerName)
{
    Q_Q(QLocalServer);

    // determine the full server path
    if (requestedServerName.startsWith(QLatin1Char('/'))) {
        fullServerName = requestedServerName;
    } else {
        fullServerName = QDir::cleanPath(QDir::tempPath());
        fullServerName += QLatin1Char('/') + requestedServerName;
    }
    serverName = requestedServerName;

    // create the unix socket
    listenSocket = qt_safe_socket(PF_UNIX, SOCK_STREAM, 0);
    if (-1 == listenSocket) {
        setError(QLatin1String("QLocalServer::listen"));
        closeServer();
        return false;
    }

    // Construct the unix address
    struct ::sockaddr_un addr;
    addr.sun_family = PF_UNIX;
    if (sizeof(addr.sun_path) < (uint)fullServerName.toLatin1().size() + 1) {
        setError(QLatin1String("QLocalServer::listen"));
        closeServer();
        return false;
    }
    ::memcpy(addr.sun_path, fullServerName.toLatin1().data(),
             fullServerName.toLatin1().size() + 1);

#ifdef Q_OS_SYMBIAN
    // In SYMBIAN OS it can currently happen that accept is called twice,
    // once from waitForNewConnection and once via QSocketNotfier activity
    //
    // As an workaround, we set the socket to non blocking so possible
    // subsequent call to accept will not block in any case
    // 
    // This change can be removed once more generic fix to select thread
    // syncronization problem is implemented.
    int flags = fcntl(listenSocket, F_GETFL, 0);
    if (-1 == flags
        || -1 == (fcntl(listenSocket, F_SETFL, flags | O_NONBLOCK))) {
        setError(QLatin1String("QLocalServer::listen"));
        closeServer();
        return false;        
    }    
#endif    
    
    // bind
    if(-1 == QT_SOCKET_BIND(listenSocket, (sockaddr *)&addr, sizeof(sockaddr_un))) {
        setError(QLatin1String("QLocalServer::listen"));
        // if address is in use already, just close the socket, but do not delete the file
        if(errno == EADDRINUSE)
            QT_CLOSE(listenSocket);
        // otherwise, close the socket and delete the file
        else
            closeServer();
        listenSocket = -1;
        return false;
    }

    // listen for connections
    if (-1 == qt_safe_listen(listenSocket, 50)) {
        setError(QLatin1String("QLocalServer::listen"));
        closeServer();
        listenSocket = -1;
        if (error != QAbstractSocket::AddressInUseError)
            QFile::remove(fullServerName);
        return false;
    }
    Q_ASSERT(!socketNotifier);
    socketNotifier = new QSocketNotifier(listenSocket,
                                         QSocketNotifier::Read, q);
    q->connect(socketNotifier, SIGNAL(activated(int)),
               q, SLOT(_q_onNewConnection()));
    socketNotifier->setEnabled(maxPendingConnections > 0);
    return true;
}

/*!
    \internal

    \sa QLocalServer::closeServer()
 */
void QLocalServerPrivate::closeServer()
{
    if (-1 != listenSocket)
        QT_CLOSE(listenSocket);
    listenSocket = -1;

    if (socketNotifier) {
        socketNotifier->setEnabled(false); // Otherwise, closed socket is checked before deleter runs
        socketNotifier->deleteLater();
        socketNotifier = 0;
    }

    if (!fullServerName.isEmpty())
        QFile::remove(fullServerName);
}

/*!
    \internal

    We have received a notification that we can read on the listen socket.
    Accept the new socket.
 */
void QLocalServerPrivate::_q_onNewConnection()
{
    Q_Q(QLocalServer);
    if (-1 == listenSocket)
        return;

    ::sockaddr_un addr;
    QT_SOCKLEN_T length = sizeof(sockaddr_un);
    int connectedSocket = qt_safe_accept(listenSocket, (sockaddr *)&addr, &length);
    if(-1 == connectedSocket) {
        setError(QLatin1String("QLocalSocket::activated"));
        closeServer();
    } else {
        socketNotifier->setEnabled(pendingConnections.size()
                                   <= maxPendingConnections);
        q->incomingConnection(connectedSocket);
    }
}

void QLocalServerPrivate::waitForNewConnection(int msec, bool *timedOut)
{
    fd_set readfds;
    FD_ZERO(&readfds);
    FD_SET(listenSocket, &readfds);

    timeval timeout;
    timeout.tv_sec = msec / 1000;
    timeout.tv_usec = (msec % 1000) * 1000;

    // timeout can not be 0 or else select will return an error.
    if (0 == msec)
        timeout.tv_usec = 1000;

    int result = -1;
    // on Linux timeout will be updated by select, but _not_ on other systems.
    QTime timer;
    timer.start();
    while (pendingConnections.isEmpty() && (-1 == msec || timer.elapsed() < msec)) {
        result = ::select(listenSocket + 1, &readfds, 0, 0, &timeout);
        if (-1 == result && errno != EINTR) {
            setError(QLatin1String("QLocalServer::waitForNewConnection"));
            closeServer();
            break;
        }
        if (result > 0)
            _q_onNewConnection();
    }
    if (timedOut)
        *timedOut = (result == 0);
}

void QLocalServerPrivate::setError(const QString &function)
{
    if (EAGAIN == errno)
        return;

    switch (errno) {
    case EACCES:
        errorString = QLocalServer::tr("%1: Permission denied").arg(function);
        error = QAbstractSocket::SocketAccessError;
        break;
    case ELOOP:
    case ENOENT:
    case ENAMETOOLONG:
    case EROFS:
    case ENOTDIR:
        errorString = QLocalServer::tr("%1: Name error").arg(function);
        error = QAbstractSocket::HostNotFoundError;
        break;
    case EADDRINUSE:
        errorString = QLocalServer::tr("%1: Address in use").arg(function);
        error = QAbstractSocket::AddressInUseError;
        break;

    default:
        errorString = QLocalServer::tr("%1: Unknown error %2")
                      .arg(function).arg(errno);
        error = QAbstractSocket::UnknownSocketError;
#if defined QLOCALSERVER_DEBUG
        qWarning() << errorString << "fullServerName:" << fullServerName;
#endif
    }
}

QT_END_NAMESPACE

#endif // QT_NO_LOCALSERVER