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****************************************************************************/

#include "qdbusmessage.h"

#include "qdbusconnection.h"

#include "qdbusabstractadaptor.h"

#include "qdbuscontext.h"

#include "qdbuscontext_p.h"

QT_BEGIN_NAMESPACE

QDBusContextPrivate *QDBusContextPrivate::set(QObject *obj, QDBusContextPrivate *newContext)

{

    // determine if this is an adaptor or not

    if (qobject_cast<QDBusAbstractAdaptor *>(obj))

        obj = obj->parent();

    Q_ASSERT(obj);

    void *ptr = obj->qt_metacast("QDBusContext");

    QDBusContext *q_ptr = reinterpret_cast<QDBusContext *>(ptr);

    if (q_ptr) {

        QDBusContextPrivate *old = q_ptr->d_ptr;

        q_ptr->d_ptr = newContext;

        return old;

    }

    return 0;

}

/*!

    \since 4.3

    \class QDBusContext

    \inmodule QtDBus

    \brief The QDBusContext class allows slots to determine the D-Bus context of the calls.

    When a slot is called in an object due to a signal delivery or due

    to a remote method call, it is sometimes necessary to know the

    context in which that happened. In particular, if the slot

    determines that it wants to send the reply at a later opportunity

    or if it wants to reply with an error, the context is needed.

    The QDBusContext class is an alternative to accessing the context

    that doesn't involve modifying the code generated by the \l

    {QtDBus XML Compiler (qdbusxml2cpp)}.

    QDBusContext is used by subclassing it from the objects being

    exported using QDBusConnection::registerObject(). The following

    example illustrates the usage:

    \snippet doc/src/snippets/code/src_qdbus_qdbuscontext.cpp 0

    The example illustrates the two typical uses, that of sending

    error replies and that of delayed replies.

    Note: do not subclass QDBusContext and QDBusAbstractAdaptor at the

    same time. QDBusContext should appear in the real object, not the

    adaptor. If it's necessary from the adaptor code to determine the

    context, use a public inheritance and access the functions via

    QObject::parent().

*/

/*!

  Constructs an empty QDBusContext.

 */

QDBusContext::QDBusContext()

    : d_ptr(0)

{

}

/*!

  An empty destructor.

 */

QDBusContext::~QDBusContext()

{

}

/*!

    Returns true if we are processing a D-Bus call. If this function

    returns true, the rest of the functions in this class are

    available.

    Accessing those functions when this function returns false is

    undefined and may lead to crashes.

*/

bool QDBusContext::calledFromDBus() const

{

    return d_ptr;

}

/*!

    Returns the connection from which this call was received.

*/

QDBusConnection QDBusContext::connection() const

{

    return d_ptr->connection;

}

/*!

    Returns the message that generated this call.

*/

const QDBusMessage &QDBusContext::message() const

{

    return d_ptr->message;

}

/*!

    Returns true if this call will have a delayed reply.

    \sa setDelayedReply()

*/

bool QDBusContext::isDelayedReply() const

{

    return message().isDelayedReply();

}

/*!

    Sets whether this call will have a delayed reply or not.

    If \a enable is false, QtDBus will automatically generate a reply

    back to the caller, if needed, as soon as the called slot returns.

    If \a enable is true, QtDBus will not generate automatic

    replies. It will also ignore the return value from the slot and

    any output parameters. Instead, the called object is responsible

    for storing the incoming message and send a reply or error at a

    later time.

    Failing to send a reply will result in an automatic timeout error

    being generated by D-Bus.

*/

void QDBusContext::setDelayedReply(bool enable) const

{

    message().setDelayedReply(enable);

}

/*!

    Sends an error \a name as a reply to the caller. The optional \a

    msg parameter is a human-readable text explaining the failure.

    If an error is sent, the return value and any output parameters

    from the called slot will be ignored by QtDBus.

*/

void QDBusContext::sendErrorReply(const QString &name, const QString &msg) const

{

    setDelayedReply(true);

    connection().send(message().createErrorReply(name, msg));

}

/*!

    \overload

    Sends an error \a type as a reply to the caller. The optional \a

    msg parameter is a human-readable text explaining the failure.

    If an error is sent, the return value and any output parameters

    from the called slot will be ignored by QtDBus.

*/

void QDBusContext::sendErrorReply(QDBusError::ErrorType type, const QString &msg) const

{

    setDelayedReply(true);

    connection().send(message().createErrorReply(type, msg));

}

QT_END_NAMESPACE