qdbusconnection.cpp

QT 开发环境里面一个很重要的文件

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#include <qdebug.h>
#include <qcoreapplication.h>
#include <qstringlist.h>

#include "qdbusconnection.h"
#include "qdbusconnectioninterface.h"
#include "qdbuserror.h"
#include "qdbusmessage.h"
#include "qdbusmessage_p.h"
#include "qdbusconnection_p.h"
#include "qdbusinterface_p.h"
#include "qdbusutil_p.h"

class QDBusConnectionManager
{
public:
    QDBusConnectionManager() {}
    ~QDBusConnectionManager();
    void bindToApplication();

    QDBusConnectionPrivate *connection(const QString &name) const;
    void removeConnection(const QString &name);
    void setConnection(const QString &name, QDBusConnectionPrivate *c);

    QDBusConnectionPrivate *sender() const;
    void setSender(const QDBusConnectionPrivate *s);

private:
    mutable QMutex mutex;
    QHash<QString, QDBusConnectionPrivate *> connectionHash;

    mutable QMutex senderMutex;
    QString senderName; // internal; will probably change
};

Q_GLOBAL_STATIC(QDBusConnectionManager, _q_manager)

QDBusConnectionPrivate *QDBusConnectionManager::sender() const
{
    QMutexLocker locker(&senderMutex);
    return connection(senderName);
}

void QDBusConnectionManager::setSender(const QDBusConnectionPrivate *s)
{
    QMutexLocker locker(&senderMutex);
    senderName = (s ? s->name : QString());
}

QDBusConnectionPrivate *QDBusConnectionManager::connection(const QString &name) const
{
    QMutexLocker locker(&mutex);
    return connectionHash.value(name, 0);
}

void QDBusConnectionManager::removeConnection(const QString &name)
{
    QMutexLocker locker(&mutex);

    QDBusConnectionPrivate *d = 0;
    d = connectionHash.take(name);
    if (d && !d->ref.deref()) {
        delete d;
    } else if (d) {
        d->closeConnection();
        qWarning("QDBusConnection: closed connection %s"
                 "is still referred to by other QDBusConnection objects",
                 name.toLocal8Bit().constData());
    }
}

QDBusConnectionManager::~QDBusConnectionManager()
{
    for (QHash<QString, QDBusConnectionPrivate *>::const_iterator it = connectionHash.constBegin();
         it != connectionHash.constEnd(); ++it) {
        QDBusConnectionPrivate *d = it.value();
        if (!d->ref.deref())
            delete d;
        else
            d->closeConnection();
    }
    connectionHash.clear();
}

void QDBusConnectionManager::bindToApplication()
{
    QMutexLocker locker(&mutex);
    for (QHash<QString, QDBusConnectionPrivate *>::const_iterator it = connectionHash.constBegin();
         it != connectionHash.constEnd(); ++it) {
             (*it)->bindToApplication();
    }
}

QDBUS_EXPORT void qDBusBindToApplication();
void qDBusBindToApplication()
{
    _q_manager()->bindToApplication();
}

void QDBusConnectionManager::setConnection(const QString &name, QDBusConnectionPrivate *c)
{
    connectionHash[name] = c;
    c->name = name;
}

/*!
    \fn QDBusConnection &QDBusConnection::sessionBus()
    \relates QDBusConnection

    Returns a QDBusConnection object opened with the session 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.
*/
/*!
    \fn QDBusConnection &QDBusConnection::systemBus()
    \relates QDBusConnection

    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.
*/

/*!
    \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.

    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 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 ExportNonScriptableContents          shorthand form for ExportNonScriptableSlots |
                                                ExportNonScriptableSignals |
                                                ExportNonScriptableProperties

    \value ExportAllSlots                       export all of this object's slots
    \value ExportAllSignal                      export all of this object's signals
    \value ExportAllProperties                  export all of this object's properties
    \value ExportAllContents                    export all of this object's contents

    \value ExportChildObjects                   export this object's child objects

    \warning It is currently not possible to export signals from
    objects. If you pass the ExportScriptableSignals,
    ExportNonScriptableSignals, or ExportAllSignal, the
    registerObject() function will print a warning.

    \sa registerObject(), QDBusAbstractAdaptor, {usingadaptors.html}{Using adaptors}
*/

/*!
    \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.
*/

/*!
    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()) {
        d = 0;
    } else {
        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())
        delete d;
}

/*!
    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();
    QDBusConnectionPrivate *old = static_cast<QDBusConnectionPrivate *>(
            q_atomic_set_ptr(&d, other.d));
    if (old && !old->ref.deref())
        delete old;

    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)