/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the QtNetwork module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 3 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL3 included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 3 requirements ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 2.0 or (at your option) the GNU General ** Public license version 3 or any later version approved by the KDE Free ** Qt Foundation. The licenses are as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 ** included in the packaging of this file. Please review the following ** information to ensure the GNU General Public License requirements will ** be met: https://www.gnu.org/licenses/gpl-2.0.html and ** https://www.gnu.org/licenses/gpl-3.0.html. ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qlocalserver.h" #include "qlocalserver_p.h" #include "qlocalsocket.h" #if defined(Q_OS_WIN) && !defined(QT_LOCALSOCKET_TCP) #include #endif QT_BEGIN_NAMESPACE /*! \class QLocalServer \since 4.4 \inmodule QtNetwork \brief The QLocalServer class provides a local socket based server. This class makes it possible to accept incoming local socket connections. Call listen() to have the server start listening for incoming connections on a specified key. The newConnection() signal is then emitted each time a client connects to the server. Call nextPendingConnection() to accept the pending connection as a connected QLocalSocket. The function returns a pointer to a QLocalSocket that can be used for communicating with the client. If an error occurs, serverError() returns the type of error, and errorString() can be called to get a human readable description of what happened. When listening for connections, the name which the server is listening on is available through serverName(). Calling close() makes QLocalServer stop listening for incoming connections. Although QLocalServer is designed for use with an event loop, it's possible to use it without one. In that case, you must use waitForNewConnection(), which blocks until either a connection is available or a timeout expires. \sa QLocalSocket, QTcpServer */ /*! \enum QLocalServer::SocketOption \since 5.0 This enum describes the possible options that can be used to create the socket. This changes the access permissions on platforms (Linux, Windows) that support access permissions on the socket. Both GroupAccess and OtherAccess may vary slightly in meanings depending on the platform. \value NoOptions No access restrictions have been set. \value UserAccessOption Access is restricted to the same user as the process that created the socket. \value GroupAccessOption Access is restricted to the same group but not the user that created the socket on Linux. Access is restricted to the primary group of the process on Windows \value OtherAccessOption Access is available to everyone but the user and group that created the socket on Linux. Access is available to everyone on Windows. \value WorldAccessOption No access restrictions. \sa socketOptions */ /*! Create a new local socket server with the given \a parent. \sa listen() */ QLocalServer::QLocalServer(QObject *parent) : QObject(*new QLocalServerPrivate, parent) { Q_D(QLocalServer); d->init(); } /*! Destroys the QLocalServer object. If the server is listening for connections, it is automatically closed. Any client QLocalSockets that are still connected must either disconnect or be reparented before the server is deleted. \sa close() */ QLocalServer::~QLocalServer() { if (isListening()) close(); } /*! \property QLocalServer::socketOptions \since 5.0 The setSocketOptions method controls how the socket operates. For example the socket may restrict access to what user ids can connect to the socket. These options must be set before listen() is called. In some cases, such as with Unix domain sockets on Linux, the access to the socket will be determined by file system permissions, and are created based on the umask. Setting the access flags will overide this and will restrict or permit access as specified. Other Unix-based operating systems, such as \macos, do not honor file permissions for Unix domain sockets and by default have WorldAccess and these permission flags will have no effect. On Windows, UserAccessOption is sufficient to allow a non elevated process to connect to a local server created by an elevated process run by the same user. GroupAccessOption refers to the primary group of the process (see TokenPrimaryGroup in the Windows documentation). OtherAccessOption refers to the well known "Everyone" group. By default none of the flags are set, access permissions are the platform default. \sa listen() */ void QLocalServer::setSocketOptions(SocketOptions options) { Q_D(QLocalServer); d->socketOptions = options; } /*! \since 5.0 Returns the socket options set on the socket. \sa setSocketOptions() */ QLocalServer::SocketOptions QLocalServer::socketOptions() const { Q_D(const QLocalServer); return d->socketOptions; } /*! \since 5.10 Returns the native socket descriptor the server uses to listen for incoming instructions, or -1 if the server is not listening. The type of the descriptor depends on the platform: \list \li On Windows, the returned value is a \l{https://msdn.microsoft.com/en-us/library/windows/desktop/ms740522(v=vs.85).aspx} {Winsock 2 Socket Handle}. \li With WinRT and on INTEGRITY, the returned value is the QTcpServer socket descriptor and the type is defined by \l{QTcpServer::socketDescriptor}{socketDescriptor}. \li On all other UNIX-like operating systems, the type is a file descriptor representing a listening socket. \endlist \sa listen() */ qintptr QLocalServer::socketDescriptor() const { Q_D(const QLocalServer); if (!isListening()) return -1; #if defined(QT_LOCALSOCKET_TCP) return d->tcpServer.socketDescriptor(); #elif defined(Q_OS_WIN) const auto handle = d->connectionEventNotifier->handle(); return handle != INVALID_HANDLE_VALUE ? qintptr(handle) : -1; #else return d->socketNotifier->socket(); #endif } /*! Stop listening for incoming connections. Existing connections are not affected, but any new connections will be refused. \sa isListening(), listen() */ void QLocalServer::close() { Q_D(QLocalServer); if (!isListening()) return; qDeleteAll(d->pendingConnections); d->pendingConnections.clear(); d->closeServer(); d->serverName.clear(); d->fullServerName.clear(); d->errorString.clear(); d->error = QAbstractSocket::UnknownSocketError; } /*! Returns the human-readable message appropriate to the current error reported by serverError(). If no suitable string is available, an empty string is returned. \sa serverError() */ QString QLocalServer::errorString() const { Q_D(const QLocalServer); return d->errorString; } /*! Returns \c true if the server has a pending connection; otherwise returns \c false. \sa nextPendingConnection(), setMaxPendingConnections() */ bool QLocalServer::hasPendingConnections() const { Q_D(const QLocalServer); return !(d->pendingConnections.isEmpty()); } /*! This virtual function is called by QLocalServer when a new connection is available. \a socketDescriptor is the native socket descriptor for the accepted connection. The base implementation creates a QLocalSocket, sets the socket descriptor and then stores the QLocalSocket in an internal list of pending connections. Finally newConnection() is emitted. Reimplement this function to alter the server's behavior when a connection is available. \sa newConnection(), nextPendingConnection(), QLocalSocket::setSocketDescriptor() */ void QLocalServer::incomingConnection(quintptr socketDescriptor) { Q_D(QLocalServer); QLocalSocket *socket = new QLocalSocket(this); socket->setSocketDescriptor(socketDescriptor); d->pendingConnections.enqueue(socket); emit newConnection(); } /*! Returns \c true if the server is listening for incoming connections otherwise false. \sa listen(), close() */ bool QLocalServer::isListening() const { Q_D(const QLocalServer); return !(d->serverName.isEmpty()); } /*! Tells the server to listen for incoming connections on \a name. If the server is currently listening then it will return false. Return true on success otherwise false. \a name can be a single name and QLocalServer will determine the correct platform specific path. serverName() will return the name that is passed into listen. Usually you would just pass in a name like "foo", but on Unix this could also be a path such as "/tmp/foo" and on Windows this could be a pipe path such as "\\\\.\\pipe\\foo" \note On Unix if the server crashes without closing listen will fail with AddressInUseError. To create a new server the file should be removed. On Windows two local servers can listen to the same pipe at the same time, but any connections will go to one of the server. \sa serverName(), isListening(), close() */ bool QLocalServer::listen(const QString &name) { Q_D(QLocalServer); if (isListening()) { qWarning("QLocalServer::listen() called when already listening"); return false; } if (name.isEmpty()) { d->error = QAbstractSocket::HostNotFoundError; QString function = QLatin1String("QLocalServer::listen"); d->errorString = tr("%1: Name error").arg(function); return false; } if (!d->listen(name)) { d->serverName.clear(); d->fullServerName.clear(); return false; } d->serverName = name; return true; } /*! \since 5.0 Instructs the server to listen for incoming connections on \a socketDescriptor. The property returns \c false if the server is currently listening. It returns \c true on success; otherwise, it returns \c false. The socket must be ready to accept new connections with no extra platform-specific functions called. The socket is set into non-blocking mode. serverName(), fullServerName() may return a string with a name if this option is supported by the platform; otherwise, they return an empty QString. \sa isListening(), close() */ bool QLocalServer::listen(qintptr socketDescriptor) { Q_D(QLocalServer); if (isListening()) { qWarning("QLocalServer::listen() called when already listening"); return false; } d->serverName.clear(); d->fullServerName.clear(); if (!d->listen(socketDescriptor)) { return false; } return true; } /*! Returns the maximum number of pending accepted connections. The default is 30. \sa setMaxPendingConnections(), hasPendingConnections() */ int QLocalServer::maxPendingConnections() const { Q_D(const QLocalServer); return d->maxPendingConnections; } /*! \fn void QLocalServer::newConnection() This signal is emitted every time a new connection is available. \sa hasPendingConnections(), nextPendingConnection() */ /*! Returns the next pending connection as a connected QLocalSocket object. The socket is created as a child of the server, which means that it is automatically deleted when the QLocalServer object is destroyed. It is still a good idea to delete the object explicitly when you are done with it, to avoid wasting memory. 0 is returned if this function is called when there are no pending connections. \sa hasPendingConnections(), newConnection(), incomingConnection() */ QLocalSocket *QLocalServer::nextPendingConnection() { Q_D(QLocalServer); if (d->pendingConnections.isEmpty()) return 0; QLocalSocket *nextSocket = d->pendingConnections.dequeue(); #ifndef QT_LOCALSOCKET_TCP if (d->pendingConnections.size() <= d->maxPendingConnections) #ifndef Q_OS_WIN d->socketNotifier->setEnabled(true); #else d->connectionEventNotifier->setEnabled(true); #endif #endif return nextSocket; } /*! \since 4.5 Removes any server instance that might cause a call to listen() to fail and returns \c true if successful; otherwise returns \c false. This function is meant to recover from a crash, when the previous server instance has not been cleaned up. On Windows, this function does nothing; on Unix, it removes the socket file given by \a name. \warning Be careful to avoid removing sockets of running instances. */ bool QLocalServer::removeServer(const QString &name) { return QLocalServerPrivate::removeServer(name); } /*! Returns the server name if the server is listening for connections; otherwise returns QString() \sa listen(), fullServerName() */ QString QLocalServer::serverName() const { Q_D(const QLocalServer); return d->serverName; } /*! Returns the full path that the server is listening on. Note: This is platform specific \sa listen(), serverName() */ QString QLocalServer::fullServerName() const { Q_D(const QLocalServer); return d->fullServerName; } /*! Returns the type of error that occurred last or NoError. \sa errorString() */ QAbstractSocket::SocketError QLocalServer::serverError() const { Q_D(const QLocalServer); return d->error; } /*! Sets the maximum number of pending accepted connections to \a numConnections. QLocalServer will accept no more than \a numConnections incoming connections before nextPendingConnection() is called. Note: Even though QLocalServer will stop accepting new connections after it has reached its maximum number of pending connections, the operating system may still keep them in queue which will result in clients signaling that it is connected. \sa maxPendingConnections(), hasPendingConnections() */ void QLocalServer::setMaxPendingConnections(int numConnections) { Q_D(QLocalServer); d->maxPendingConnections = numConnections; } /*! Waits for at most \a msec milliseconds or until an incoming connection is available. Returns \c true if a connection is available; otherwise returns \c false. If the operation timed out and \a timedOut is not 0, *timedOut will be set to true. This is a blocking function call. Its use is ill-advised in a single-threaded GUI application, since the whole application will stop responding until the function returns. waitForNewConnection() is mostly useful when there is no event loop available. The non-blocking alternative is to connect to the newConnection() signal. If msec is -1, this function will not time out. \sa hasPendingConnections(), nextPendingConnection() */ bool QLocalServer::waitForNewConnection(int msec, bool *timedOut) { Q_D(QLocalServer); if (timedOut) *timedOut = false; if (!isListening()) return false; d->waitForNewConnection(msec, timedOut); return !d->pendingConnections.isEmpty(); } QT_END_NAMESPACE #include "moc_qlocalserver.cpp"