/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Copyright (C) 2016 Intel Corporation. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the QtDBus 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 "qdbusconnection.h" #include "qdbusconnection_p.h" #include #include #include #include #include #include #include "qdbusconnectioninterface.h" #include "qdbuserror.h" #include "qdbusmessage.h" #include "qdbusmessage_p.h" #include "qdbusinterface_p.h" #include "qdbusutil_p.h" #include "qdbusconnectionmanager_p.h" #include "qdbuspendingcall_p.h" #include "qdbusthreaddebug_p.h" #include #ifdef interface #undef interface #endif #ifndef QT_NO_DBUS QT_BEGIN_NAMESPACE #ifdef Q_OS_WIN static void preventDllUnload(); #endif Q_GLOBAL_STATIC(QDBusConnectionManager, _q_manager) struct QDBusConnectionManager::ConnectionRequestData { enum RequestType { ConnectToStandardBus, ConnectToBusByAddress, ConnectToPeerByAddress } type; union { QDBusConnection::BusType busType; const QString *busAddress; }; const QString *name; QDBusConnectionPrivate *result; bool suspendedDelivery; }; QDBusConnectionPrivate *QDBusConnectionManager::busConnection(QDBusConnection::BusType type) { Q_STATIC_ASSERT(int(QDBusConnection::SessionBus) + int(QDBusConnection::SystemBus) == 1); Q_ASSERT(type == QDBusConnection::SessionBus || type == QDBusConnection::SystemBus); if (!qdbus_loadLibDBus()) return 0; // we'll start in suspended delivery mode if we're in the main thread // (the event loop will resume delivery) bool suspendedDelivery = qApp && qApp->thread() == QThread::currentThread(); QMutexLocker lock(&defaultBusMutex); if (defaultBuses[type]) return defaultBuses[type]; QString name = QStringLiteral("qt_default_session_bus"); if (type == QDBusConnection::SystemBus) name = QStringLiteral("qt_default_system_bus"); return defaultBuses[type] = connectToBus(type, name, suspendedDelivery); } QDBusConnectionPrivate *QDBusConnectionManager::connection(const QString &name) const { return connectionHash.value(name, 0); } void QDBusConnectionManager::removeConnection(const QString &name) { QDBusConnectionPrivate *d = 0; d = connectionHash.take(name); if (d && !d->ref.deref()) d->deleteLater(); // Static objects may be keeping the connection open. // However, it is harmless to have outstanding references to a connection that is // closing as long as those references will be soon dropped without being used. // ### Output a warning if connections are being used after they have been removed. } QDBusConnectionManager::QDBusConnectionManager() { connect(this, &QDBusConnectionManager::connectionRequested, this, &QDBusConnectionManager::executeConnectionRequest, Qt::BlockingQueuedConnection); connect(this, &QDBusConnectionManager::serverRequested, this, &QDBusConnectionManager::createServer, Qt::BlockingQueuedConnection); moveToThread(this); // ugly, don't do this in other projects #ifdef Q_OS_WIN // prevent the library from being unloaded on Windows. See comments in the function. preventDllUnload(); #endif defaultBuses[0] = defaultBuses[1] = Q_NULLPTR; start(); } QDBusConnectionManager::~QDBusConnectionManager() { quit(); wait(); } QDBusConnectionManager* QDBusConnectionManager::instance() { return _q_manager(); } Q_DBUS_EXPORT void qDBusBindToApplication(); void qDBusBindToApplication() { } void QDBusConnectionManager::setConnection(const QString &name, QDBusConnectionPrivate *c) { connectionHash[name] = c; c->name = name; } void QDBusConnectionManager::run() { exec(); // cleanup: QMutexLocker locker(&mutex); for (QHash::const_iterator it = connectionHash.constBegin(); it != connectionHash.constEnd(); ++it) { QDBusConnectionPrivate *d = it.value(); if (!d->ref.deref()) { delete d; } else { d->closeConnection(); d->moveToThread(Q_NULLPTR); // allow it to be deleted in another thread } } connectionHash.clear(); // allow deletion from any thread without warning moveToThread(Q_NULLPTR); } QDBusConnectionPrivate *QDBusConnectionManager::connectToBus(QDBusConnection::BusType type, const QString &name, bool suspendedDelivery) { ConnectionRequestData data; data.type = ConnectionRequestData::ConnectToStandardBus; data.busType = type; data.name = &name; data.suspendedDelivery = suspendedDelivery; emit connectionRequested(&data); if (suspendedDelivery && data.result->connection) { data.result->ref.ref(); QDBusConnectionDispatchEnabler *o = new QDBusConnectionDispatchEnabler(data.result); QTimer::singleShot(0, o, SLOT(execute())); o->moveToThread(qApp->thread()); // qApp was checked in the caller } return data.result; } QDBusConnectionPrivate *QDBusConnectionManager::connectToBus(const QString &address, const QString &name) { ConnectionRequestData data; data.type = ConnectionRequestData::ConnectToBusByAddress; data.busAddress = &address; data.name = &name; data.suspendedDelivery = false; emit connectionRequested(&data); return data.result; } QDBusConnectionPrivate *QDBusConnectionManager::connectToPeer(const QString &address, const QString &name) { ConnectionRequestData data; data.type = ConnectionRequestData::ConnectToPeerByAddress; data.busAddress = &address; data.name = &name; data.suspendedDelivery = false; emit connectionRequested(&data); return data.result; } void QDBusConnectionManager::executeConnectionRequest(QDBusConnectionManager::ConnectionRequestData *data) { QMutexLocker locker(&mutex); const QString &name = *data->name; QDBusConnectionPrivate *&d = data->result; // check if the connection exists by name d = connection(name); if (d || name.isEmpty()) return; d = new QDBusConnectionPrivate; DBusConnection *c = 0; QDBusErrorInternal error; switch (data->type) { case ConnectionRequestData::ConnectToStandardBus: switch (data->busType) { case QDBusConnection::SystemBus: c = q_dbus_bus_get_private(DBUS_BUS_SYSTEM, error); break; case QDBusConnection::SessionBus: c = q_dbus_bus_get_private(DBUS_BUS_SESSION, error); break; case QDBusConnection::ActivationBus: c = q_dbus_bus_get_private(DBUS_BUS_STARTER, error); break; } break; case ConnectionRequestData::ConnectToBusByAddress: case ConnectionRequestData::ConnectToPeerByAddress: c = q_dbus_connection_open_private(data->busAddress->toUtf8().constData(), error); if (c && data->type == ConnectionRequestData::ConnectToBusByAddress) { // register on the bus if (!q_dbus_bus_register(c, error)) { q_dbus_connection_unref(c); c = 0; } } break; } setConnection(name, d); if (data->type == ConnectionRequestData::ConnectToPeerByAddress) { d->setPeer(c, error); } else { // create the bus service // will lock in QDBusConnectionPrivate::connectRelay() d->setConnection(c, error); d->createBusService(); if (c && data->suspendedDelivery) d->setDispatchEnabled(false); } } void QDBusConnectionManager::createServer(const QString &address, void *server) { QDBusErrorInternal error; QDBusConnectionPrivate *d = new QDBusConnectionPrivate; d->setServer(static_cast(server), q_dbus_server_listen(address.toUtf8().constData(), error), error); } /*! \class QDBusConnection \inmodule QtDBus \since 4.2 \brief The QDBusConnection class represents a connection to the D-Bus bus daemon. This class is the initial point in a D-Bus session. Using it, you can get access to remote objects, interfaces; connect remote signals to your object's slots; register objects, etc. D-Bus connections are created using the connectToBus() function, which opens a connection to the server daemon and does the initial handshaking, associating that connection with a name. Further attempts to connect using the same name will return the same connection. The connection is then torn down using the disconnectFromBus() function. Once disconnected, calling connectToBus() will not reestablish a connection, you must create a new QDBusConnection instance. As a convenience for the two most common connection types, the sessionBus() and systemBus() functions return open connections to the session server daemon and the system server daemon, respectively. Those connections are opened when first used and are closed when the QCoreApplication destructor is run. D-Bus also supports peer-to-peer connections, without the need for a bus server daemon. Using this facility, two applications can talk to each other and exchange messages. This can be achieved by passing an address to connectToBus() function, which was opened by another D-Bus application using QDBusServer. */ /*! \enum QDBusConnection::BusType Specifies the type of the bus connection. The valid bus types are: \value SessionBus the session bus, associated with the running desktop session \value SystemBus the system bus, used to communicate with system-wide processes \value ActivationBus the activation bus, the "alias" for the bus that started the service On the Session Bus, one can find other applications by the same user that are sharing the same desktop session (hence the name). On the System Bus, however, processes shared for the whole system are usually found. */ /*! \enum QDBusConnection::RegisterOption Specifies the options for registering objects with the connection. The possible values are: \value ExportAdaptors export the contents of adaptors found in this object \value ExportScriptableSlots export this object's scriptable slots \value ExportScriptableSignals export this object's scriptable signals \value ExportScriptableProperties export this object's scriptable properties \value ExportScriptableInvokables export this object's scriptable invokables \value ExportScriptableContents shorthand form for ExportScriptableSlots | ExportScriptableSignals | ExportScriptableProperties \value ExportNonScriptableSlots export this object's non-scriptable slots \value ExportNonScriptableSignals export this object's non-scriptable signals \value ExportNonScriptableProperties export this object's non-scriptable properties \value ExportNonScriptableInvokables export this object's non-scriptable invokables \value ExportNonScriptableContents shorthand form for ExportNonScriptableSlots | ExportNonScriptableSignals | ExportNonScriptableProperties \value ExportAllSlots export all of this object's slots \value ExportAllSignals export all of this object's signals \value ExportAllProperties export all of this object's properties \value ExportAllInvokables export all of this object's invokables \value ExportAllContents export all of this object's contents \value ExportChildObjects export this object's child objects \sa registerObject(), QDBusAbstractAdaptor, {usingadaptors.html}{Using adaptors} */ /*! \internal \since 4.8 \enum QDBusConnection::VirtualObjectRegisterOption Specifies the options for registering virtual objects with the connection. The possible values are: \value SingleNode register a virtual object to handle one path only \value SubPath register a virtual object so that it handles all sub paths \sa registerVirtualObject(), QDBusVirtualObject */ /*! \enum QDBusConnection::UnregisterMode The mode for unregistering an object path: \value UnregisterNode unregister this node only: do not unregister child objects \value UnregisterTree unregister this node and all its sub-tree Note, however, if this object was registered with the ExportChildObjects option, UnregisterNode will unregister the child objects too. */ /*! \since 4.8 \enum QDBusConnection::ConnectionCapability This enum describes the available capabilities for a D-Bus connection. \value UnixFileDescriptorPassing enables passing of Unix file descriptors to other processes (see QDBusUnixFileDescriptor) \sa connectionCapabilities() */ /*! Creates a QDBusConnection object attached to the connection with name \a name. This does not open the connection. You have to call connectToBus() to open it. */ QDBusConnection::QDBusConnection(const QString &name) { if (name.isEmpty() || _q_manager.isDestroyed()) { d = 0; } else { QMutexLocker locker(&_q_manager()->mutex); d = _q_manager()->connection(name); if (d) d->ref.ref(); } } /*! Creates a copy of the \a other connection. */ QDBusConnection::QDBusConnection(const QDBusConnection &other) { d = other.d; if (d) d->ref.ref(); } /*! \internal Creates a connection object with the given \a dd as private object. */ QDBusConnection::QDBusConnection(QDBusConnectionPrivate *dd) { d = dd; if (d) d->ref.ref(); } /*! Disposes of this object. This does not close the connection: you have to call disconnectFromBus() to do that. */ QDBusConnection::~QDBusConnection() { if (d && !d->ref.deref()) d->deleteLater(); } /*! Creates a copy of the connection \a other in this object. Note that the connection this object referenced before the copy, is not spontaneously disconnected. \sa disconnectFromBus() */ QDBusConnection &QDBusConnection::operator=(const QDBusConnection &other) { if (other.d) other.d->ref.ref(); if (d && !d->ref.deref()) d->deleteLater(); d = other.d; return *this; } /*! Opens a connection of type \a type to one of the known busses and associate with it the connection name \a name. Returns a QDBusConnection object associated with that connection. */ QDBusConnection QDBusConnection::connectToBus(BusType type, const QString &name) { if (_q_manager.isDestroyed() || !qdbus_loadLibDBus()) { QDBusConnectionPrivate *d = 0; return QDBusConnection(d); } return QDBusConnection(_q_manager()->connectToBus(type, name, false)); } /*! Opens a connection to a private bus on address \a address and associate with it the connection name \a name. Returns a QDBusConnection object associated with that connection. */ QDBusConnection QDBusConnection::connectToBus(const QString &address, const QString &name) { if (_q_manager.isDestroyed() || !qdbus_loadLibDBus()) { QDBusConnectionPrivate *d = 0; return QDBusConnection(d); } return QDBusConnection(_q_manager()->connectToBus(address, name)); } /*! \since 4.8 Opens a peer-to-peer connection on address \a address and associate with it the connection name \a name. Returns a QDBusConnection object associated with that connection. */ QDBusConnection QDBusConnection::connectToPeer(const QString &address, const QString &name) { if (_q_manager.isDestroyed() || !qdbus_loadLibDBus()) { QDBusConnectionPrivate *d = 0; return QDBusConnection(d); } return QDBusConnection(_q_manager()->connectToPeer(address, name)); } /*! Closes the bus connection of name \a name. Note that if there are still QDBusConnection objects associated with the same connection, the connection will not be closed until all references are dropped. However, no further references can be created using the QDBusConnection constructor. */ void QDBusConnection::disconnectFromBus(const QString &name) { if (_q_manager()) { QMutexLocker locker(&_q_manager()->mutex); QDBusConnectionPrivate *d = _q_manager()->connection(name); if (d && d->mode != QDBusConnectionPrivate::ClientMode) return; _q_manager()->removeConnection(name); } } /*! \since 4.8 Closes the peer connection of name \a name. Note that if there are still QDBusConnection objects associated with the same connection, the connection will not be closed until all references are dropped. However, no further references can be created using the QDBusConnection constructor. */ void QDBusConnection::disconnectFromPeer(const QString &name) { if (_q_manager()) { QMutexLocker locker(&_q_manager()->mutex); QDBusConnectionPrivate *d = _q_manager()->connection(name); if (d && d->mode != QDBusConnectionPrivate::PeerMode) return; _q_manager()->removeConnection(name); } } /*! Sends the \a message over this connection, without waiting for a reply. This is suitable for errors, signals, and return values as well as calls whose return values are not necessary. Returns \c true if the message was queued successfully, false otherwise. */ bool QDBusConnection::send(const QDBusMessage &message) const { if (!d || !d->connection) { QDBusError err = QDBusError(QDBusError::Disconnected, QDBusUtil::disconnectedErrorMessage()); if (d) d->lastError = err; return false; } return d->send(message); } /*! Sends the \a message over this connection and returns immediately. When the reply is received, the method \a returnMethod is called in the \a receiver object. If an error occurs, the method \a errorMethod will be called instead. If no reply is received within \a timeout milliseconds, an automatic error will be delivered indicating the expiration of the call. The default \a timeout is -1, which will be replaced with an implementation-defined value that is suitable for inter-process communications (generally, 25 seconds). This function is suitable for method calls only. It is guaranteed that the slot will be called exactly once with the reply, as long as the parameter types match and no error occurs. Returns \c true if the message was sent, or false if the message could not be sent. */ bool QDBusConnection::callWithCallback(const QDBusMessage &message, QObject *receiver, const char *returnMethod, const char *errorMethod, int timeout) const { if (!d || !d->connection) { QDBusError err = QDBusError(QDBusError::Disconnected, QDBusUtil::disconnectedErrorMessage()); if (d) d->lastError = err; return false; } return d->sendWithReplyAsync(message, receiver, returnMethod, errorMethod, timeout) != 0; } /*! \overload \deprecated Sends the \a message over this connection and returns immediately. When the reply is received, the method \a returnMethod is called in the \a receiver object. This function is suitable for method calls only. It is guaranteed that the slot will be called exactly once with the reply, as long as the parameter types match and no error occurs. This function is dangerous because it cannot report errors, including the expiration of the timeout. Returns \c true if the message was sent, or false if the message could not be sent. */ bool QDBusConnection::callWithCallback(const QDBusMessage &message, QObject *receiver, const char *returnMethod, int timeout) const { return callWithCallback(message, receiver, returnMethod, 0, timeout); } /*! Sends the \a message over this connection and blocks, waiting for a reply, for at most \a timeout milliseconds. This function is suitable for method calls only. It returns the reply message as its return value, which will be either of type QDBusMessage::ReplyMessage or QDBusMessage::ErrorMessage. If no reply is received within \a timeout milliseconds, an automatic error will be delivered indicating the expiration of the call. The default \a timeout is -1, which will be replaced with an implementation-defined value that is suitable for inter-process communications (generally, 25 seconds). See the QDBusInterface::call() function for a more friendly way of placing calls. \warning If \a mode is QDBus::BlockWithGui, this function will reenter the Qt event loop in order to wait for the reply. During the wait, it may deliver signals and other method calls to your application. Therefore, it must be prepared to handle a reentrancy whenever a call is placed with call(). */ QDBusMessage QDBusConnection::call(const QDBusMessage &message, QDBus::CallMode mode, int timeout) const { if (!d || !d->connection) { QDBusError err = QDBusError(QDBusError::Disconnected, QDBusUtil::disconnectedErrorMessage()); if (d) d->lastError = err; return QDBusMessage::createError(err); } if (mode != QDBus::NoBlock) return d->sendWithReply(message, mode, timeout); d->send(message); QDBusMessage retval; retval << QVariant(); // add one argument (to avoid .at(0) problems) return retval; } /*! \since 4.5 Sends the \a message over this connection and returns immediately. This function is suitable for method calls only. It returns an object of type QDBusPendingCall which can be used to track the status of the reply. If no reply is received within \a timeout milliseconds, an automatic error will be delivered indicating the expiration of the call. The default \a timeout is -1, which will be replaced with an implementation-defined value that is suitable for inter-process communications (generally, 25 seconds). This timeout is also the upper limit for waiting in QDBusPendingCall::waitForFinished(). See the QDBusInterface::asyncCall() function for a more friendly way of placing calls. */ QDBusPendingCall QDBusConnection::asyncCall(const QDBusMessage &message, int timeout) const { if (!d || !d->connection) { return QDBusPendingCall(0); // null pointer -> disconnected } QDBusPendingCallPrivate *priv = d->sendWithReplyAsync(message, 0, 0, 0, timeout); return QDBusPendingCall(priv); } /*! Connects the signal specified by the \a service, \a path, \a interface and \a name parameters to the slot \a slot in object \a receiver. The arguments \a service and \a path can be empty, denoting a connection to any signal of the (\a interface, \a name) pair, from any remote application. Returns \c true if the connection was successful. \warning The signal will only be delivered to the slot if the parameters match. This verification can be done only when the signal is received, not at connection time. */ bool QDBusConnection::connect(const QString &service, const QString &path, const QString& interface, const QString &name, QObject *receiver, const char *slot) { return connect(service, path, interface, name, QStringList(), QString(), receiver, slot); } /*! \overload Connects the signal to the slot \a slot in object \a receiver. Unlike the previous connect() overload, this function allows one to specify the parameter signature to be connected using the \a signature variable. The function will then verify that this signature can be delivered to the slot specified by \a slot and return false otherwise. Returns \c true if the connection was successful. \note This function verifies that the signal signature matches the slot's parameters, but it does not verify that the actual signal exists with the given signature in the remote service. */ bool QDBusConnection::connect(const QString &service, const QString &path, const QString& interface, const QString &name, const QString &signature, QObject *receiver, const char *slot) { return connect(service, path, interface, name, QStringList(), signature, receiver, slot); } /*! \overload \since 4.6 Connects the signal to the slot \a slot in object \a receiver. Unlike the previous connect() overload, this function allows one to specify the parameter signature to be connected using the \a signature variable. The function will then verify that this signature can be delivered to the slot specified by \a slot and return false otherwise. The \a argumentMatch parameter lists the string parameters to be matched, in sequential order. Note that, to match an empty string, you need to pass a QString that is empty but not null (i.e., QString("")). A null QString skips matching at that position. Returns \c true if the connection was successful. \note This function verifies that the signal signature matches the slot's parameters, but it does not verify that the actual signal exists with the given signature in the remote service. */ bool QDBusConnection::connect(const QString &service, const QString &path, const QString& interface, const QString &name, const QStringList &argumentMatch, const QString &signature, QObject *receiver, const char *slot) { if (!receiver || !slot || !d || !d->connection) return false; if (interface.isEmpty() && name.isEmpty()) return false; if (!interface.isEmpty() && !QDBusUtil::isValidInterfaceName(interface)) { #ifndef QT_NO_DEBUG qWarning("QDBusConnection::connect: interface name '%s' is not valid", interface.toLatin1().constData()); #endif return false; } if (!service.isEmpty() && !QDBusUtil::isValidBusName(service)) { #ifndef QT_NO_DEBUG qWarning("QDBusConnection::connect: service name '%s' is not valid", service.toLatin1().constData()); #endif return false; } if (!path.isEmpty() && !QDBusUtil::isValidObjectPath(path)) { #ifndef QT_NO_DEBUG qWarning("QDBusConnection::connect: object path '%s' is not valid", path.toLatin1().constData()); #endif return false; } return d->connectSignal(service, path, interface, name, argumentMatch, signature, receiver, slot); } /*! Disconnects the signal specified by the \a service, \a path, \a interface and \a name parameters from the slot \a slot in object \a receiver. The arguments must be the same as passed to the connect() function. Returns \c true if the disconnection was successful. */ bool QDBusConnection::disconnect(const QString &service, const QString &path, const QString &interface, const QString &name, QObject *receiver, const char *slot) { return disconnect(service, path, interface, name, QStringList(), QString(), receiver, slot); } /*! \overload Disconnects the signal specified by the \a service, \a path, \a interface, \a name, and \a signature parameters from the slot \a slot in object \a receiver. The arguments must be the same as passed to the connect() function. Returns \c true if the disconnection was successful. */ bool QDBusConnection::disconnect(const QString &service, const QString &path, const QString& interface, const QString &name, const QString &signature, QObject *receiver, const char *slot) { return disconnect(service, path, interface, name, QStringList(), signature, receiver, slot); } /*! \overload \since 4.6 Disconnects the signal specified by the \a service, \a path, \a interface, \a name, \a argumentMatch, and \a signature parameters from the slot \a slot in object \a receiver. The arguments must be the same as passed to the connect() function. Returns \c true if the disconnection was successful. */ bool QDBusConnection::disconnect(const QString &service, const QString &path, const QString& interface, const QString &name, const QStringList &argumentMatch, const QString &signature, QObject *receiver, const char *slot) { if (!receiver || !slot || !d || !d->connection) return false; if (!interface.isEmpty() && !QDBusUtil::isValidInterfaceName(interface)) return false; if (interface.isEmpty() && name.isEmpty()) return false; return d->disconnectSignal(service, path, interface, name, argumentMatch, signature, receiver, slot); } /*! Registers the object \a object at path \a path and returns \c true if the registration was successful. The \a options parameter specifies how much of the object \a object will be exposed through D-Bus. This function does not replace existing objects: if there is already an object registered at path \a path, this function will return false. Use unregisterObject() to unregister it first. You cannot register an object as a child object of an object that was registered with QDBusConnection::ExportChildObjects. */ bool QDBusConnection::registerObject(const QString &path, QObject *object, RegisterOptions options) { return registerObject(path, QString(), object, options); } /*! \overload \since 5.5 Registers the object \a object at path \a path with interface name \a interface and returns \c true if the registration was successful. The \a options parameter specifies how much of the object \a object will be exposed through D-Bus. This function does not replace existing objects: if there is already an object registered at path \a path, this function will return false. Use unregisterObject() to unregister it first. You cannot register an object as a child object of an object that was registered with QDBusConnection::ExportChildObjects. */ bool QDBusConnection::registerObject(const QString &path, const QString &interface, QObject *object, RegisterOptions options) { Q_ASSERT_X(QDBusUtil::isValidObjectPath(path), "QDBusConnection::registerObject", "Invalid object path given"); if (!d || !d->connection || !object || !options || !QDBusUtil::isValidObjectPath(path)) return false; auto pathComponents = path.splitRef(QLatin1Char('/')); if (pathComponents.constLast().isEmpty()) pathComponents.removeLast(); QDBusWriteLocker locker(RegisterObjectAction, d); // lower-bound search for where this object should enter in the tree QDBusConnectionPrivate::ObjectTreeNode::DataList::Iterator node = &d->rootNode; int i = 1; while (node) { if (pathComponents.count() == i) { // this node exists // consider it free if there's no object here and the user is not trying to // replace the object sub-tree if (node->obj) return false; if (options & QDBusConnectionPrivate::VirtualObject) { if (options & SubPath && !node->children.isEmpty()) return false; } else { if ((options & ExportChildObjects && !node->children.isEmpty())) return false; } // we can add the object here node->obj = object; node->flags = options; node->interfaceName = interface; d->registerObject(node); //qDebug("REGISTERED FOR %s", path.toLocal8Bit().constData()); return true; } // if a virtual object occupies this path, return false if (node->obj && (node->flags & QDBusConnectionPrivate::VirtualObject) && (node->flags & QDBusConnection::SubPath)) { //qDebug("Cannot register object at %s because QDBusVirtualObject handles all sub-paths.", // qPrintable(path)); return false; } // find the position where we'd insert the node QDBusConnectionPrivate::ObjectTreeNode::DataList::Iterator it = std::lower_bound(node->children.begin(), node->children.end(), pathComponents.at(i)); if (it != node->children.end() && it->name == pathComponents.at(i)) { // match: this node exists node = it; // are we allowed to go deeper? if (node->flags & ExportChildObjects) { // we're not //qDebug("Cannot register object at %s because %s exports its own child objects", // qPrintable(path), qPrintable(pathComponents.at(i))); return false; } } else { // add entry node = node->children.insert(it, pathComponents.at(i).toString()); } // iterate ++i; } Q_ASSERT_X(false, "QDBusConnection::registerObject", "The impossible happened"); return false; } /*! \internal \since 4.8 Registers a QDBusTreeNode for a path. It can handle a path including all child paths, thus handling multiple DBus nodes. To unregister a QDBusTreeNode use the unregisterObject() function with its path. */ bool QDBusConnection::registerVirtualObject(const QString &path, QDBusVirtualObject *treeNode, VirtualObjectRegisterOption options) { int opts = options | QDBusConnectionPrivate::VirtualObject; return registerObject(path, (QObject*) treeNode, (RegisterOptions) opts); } /*! Unregisters an object that was registered with the registerObject() at the object path given by \a path and, if \a mode is QDBusConnection::UnregisterTree, all of its sub-objects too. Note that you cannot unregister objects that were not registered with registerObject(). */ void QDBusConnection::unregisterObject(const QString &path, UnregisterMode mode) { if (!d || !d->connection || !QDBusUtil::isValidObjectPath(path)) return; QDBusWriteLocker locker(UnregisterObjectAction, d); d->unregisterObject(path, mode); } /*! Return the object that was registered with the registerObject() at the object path given by \a path. */ QObject *QDBusConnection::objectRegisteredAt(const QString &path) const { Q_ASSERT_X(QDBusUtil::isValidObjectPath(path), "QDBusConnection::registeredObject", "Invalid object path given"); if (!d || !d->connection || !QDBusUtil::isValidObjectPath(path)) return 0; auto pathComponents = path.splitRef(QLatin1Char('/')); if (pathComponents.constLast().isEmpty()) pathComponents.removeLast(); // lower-bound search for where this object should enter in the tree QDBusReadLocker lock(ObjectRegisteredAtAction, d); const QDBusConnectionPrivate::ObjectTreeNode *node = &d->rootNode; int i = 1; while (node) { if (pathComponents.count() == i) return node->obj; if ((node->flags & QDBusConnectionPrivate::VirtualObject) && (node->flags & QDBusConnection::SubPath)) return node->obj; QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator it = std::lower_bound(node->children.constBegin(), node->children.constEnd(), pathComponents.at(i)); if (it == node->children.constEnd() || it->name != pathComponents.at(i)) break; // node not found node = it; ++i; } return 0; } /*! Returns a QDBusConnectionInterface object that represents the D-Bus server interface on this connection. */ QDBusConnectionInterface *QDBusConnection::interface() const { if (!d || d->mode != QDBusConnectionPrivate::ClientMode) return 0; return d->busService; } /*! \internal \since 4.8 Returns the internal, implementation-defined pointer for this connection. Currently, this returns a DBusConnection* pointer, without changing the reference count. It is the responsibility of the caller to call dbus_connection_ref if it wants to store the pointer. */ void *QDBusConnection::internalPointer() const { return d ? d->connection : 0; } /*! Returns \c true if this QDBusConnection object is connected. */ bool QDBusConnection::isConnected() const { return d && d->connection && q_dbus_connection_get_is_connected(d->connection); } /*! Returns the last error that happened in this connection. This function is provided for low-level code. If you're using QDBusInterface::call(), error codes are reported by its return value. \sa QDBusInterface, QDBusMessage */ QDBusError QDBusConnection::lastError() const { return d ? d->lastError : QDBusError(QDBusError::Disconnected, QDBusUtil::disconnectedErrorMessage()); } /*! Returns the unique connection name for this connection, if this QDBusConnection object is connected, or an empty QString otherwise. A Unique Connection Name is a string in the form ":x.xxx" (where x are decimal digits) that is assigned by the D-Bus server daemon upon connection. It uniquely identifies this client in the bus. This function returns an empty QString for peer-to-peer connections. */ QString QDBusConnection::baseService() const { return d ? d->baseService : QString(); } /*! \since 4.5 Returns the connection name for this connection, as given as the name parameter to connectToBus(). The connection name can be used to uniquely identify actual underlying connections to buses. Copies made from a single connection will always implicitly share the underlying connection, and hence will have the same connection name. Inversely, two connections having different connection names will always either be connected to different buses, or have a different unique name (as returned by baseService()) on that bus. \sa connectToBus(), disconnectFromBus() */ QString QDBusConnection::name() const { return d ? d->name : QString(); } /*! \since 4.8 Returns the capabilities of this connection as negotiated with the bus server or peer. If this QDBusConnection is not connected, this function returns no capabilities. */ QDBusConnection::ConnectionCapabilities QDBusConnection::connectionCapabilities() const { return d ? d->capabilities : ConnectionCapabilities(0); } /*! Attempts to register the \a serviceName on the D-Bus server and returns \c true if the registration succeeded. The registration will fail if the name is already registered by another application. \sa unregisterService(), QDBusConnectionInterface::registerService() */ bool QDBusConnection::registerService(const QString &serviceName) { if (interface() && interface()->registerService(serviceName)) { if (d) d->registerService(serviceName); return true; } return false; } /*! Unregisters the service \a serviceName that was previously registered with registerService() and returns \c true if it succeeded. \sa registerService(), QDBusConnectionInterface::unregisterService() */ bool QDBusConnection::unregisterService(const QString &serviceName) { if (interface()->unregisterService(serviceName)) { if (d) d->unregisterService(serviceName); return true; } return false; } /*! \fn QDBusConnection QDBusConnection::sessionBus() Returns a QDBusConnection object opened with the session bus. The object reference returned by this function is valid until the application terminates, at which point the connection will be closed and the object deleted. */ QDBusConnection QDBusConnection::sessionBus() { if (_q_manager.isDestroyed()) return QDBusConnection(Q_NULLPTR); return QDBusConnection(_q_manager()->busConnection(SessionBus)); } /*! \fn QDBusConnection QDBusConnection::systemBus() Returns a QDBusConnection object opened with the system bus. The object reference returned by this function is valid until the QCoreApplication's destructor is run, when the connection will be closed and the object, deleted. */ QDBusConnection QDBusConnection::systemBus() { if (_q_manager.isDestroyed()) return QDBusConnection(Q_NULLPTR); return QDBusConnection(_q_manager()->busConnection(SystemBus)); } #if QT_DEPRECATED_SINCE(5,5) /*! \deprecated Always returns a disconnected, invalid QDBusConnection object. For the old functionality of determining the sender connection, please use QDBusContext. \sa QDBusContext */ QDBusConnection QDBusConnection::sender() { return QDBusConnection(QString()); } #endif /*! \internal */ void QDBusConnectionPrivate::createBusService() { Q_ASSERT(mode == ClientMode); QDBusConnection connection(this); busService = new QDBusConnectionInterface(connection, this); ref.deref(); // busService has increased the refcounting to us // avoid cyclic refcounting QObject::connect(this, &QDBusConnectionPrivate::callWithCallbackFailed, busService, emit &QDBusConnectionInterface::callWithCallbackFailed, Qt::QueuedConnection); } /*! \since 4.8 Returns the local machine ID as known to the D-Bus system. Each node or host that runs D-Bus has a unique identifier that can be used to distinguish it from other hosts if they are sharing resources like the filesystem. Note that the local machine ID is not guaranteed to be persistent across boots of the system, so this identifier should not be stored in persistent storage (like the filesystem). It is guaranteed to remain constant only during the lifetime of this boot session. */ QByteArray QDBusConnection::localMachineId() { char *dbus_machine_id = q_dbus_get_local_machine_id(); QByteArray result = dbus_machine_id; q_dbus_free(dbus_machine_id); return result; } /*! \namespace QDBus \inmodule QtDBus \brief The QDBus namespace contains miscellaneous identifiers used throughout the Qt D-Bus module. */ /*! \enum QDBus::CallMode This enum describes the various ways of placing a function call. The valid modes are: \value NoBlock Place the call but don't wait for the reply (the reply's contents will be discarded). \value Block Don't use an event loop to wait for a reply, but instead block on network operations while waiting. This means the user-interface may not be updated until the function returns. \value BlockWithGui Use the Qt event loop to wait for a reply. This means that the user-interface will stay responsive (processing input events), but it also means other events may happen, like signal delivery and other D-Bus method calls. \value AutoDetect Automatically detect if the called function has a reply. When using BlockWithGui, applications must be prepared for reentrancy in any function. */ QT_END_NAMESPACE #ifdef Q_OS_WIN # include QT_BEGIN_NAMESPACE static void preventDllUnload() { // Thread termination is really wacky on Windows. For some reason we don't // understand, exiting from the thread may try to unload the DLL. Since the // QDBusConnectionManager thread runs until the DLL is unloaded, we've got // a deadlock: the main thread is waiting for the manager thread to exit, // but the manager thread is attempting to acquire a lock to unload the DLL. // // We work around the issue by preventing the unload from happening in the // first place. // // For this trick, see // https://blogs.msdn.microsoft.com/oldnewthing/20131105-00/?p=2733 static HMODULE self; GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS | GET_MODULE_HANDLE_EX_FLAG_PIN, reinterpret_cast(&self), // any address in this DLL &self); } QT_END_NAMESPACE #endif #endif // QT_NO_DBUS