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/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtDBus module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** 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
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qdbusreply.h"
#include "qdbusmetatype.h"
#include "qdbusmetatype_p.h"
#include <QDebug>
#ifndef QT_NO_DBUS
QT_BEGIN_NAMESPACE
/*!
\class QDBusReply
\inmodule QtDBus
\since 4.2
\brief The QDBusReply class stores the reply for a method call to a remote object.
A QDBusReply object is a subset of the QDBusMessage object that represents a method call's
reply. It contains only the first output argument or the error code and is used by
QDBusInterface-derived classes to allow returning the error code as the function's return
argument.
It can be used in the following manner:
\snippet doc/src/snippets/code/src_qdbus_qdbusreply.cpp 0
If the remote method call cannot fail, you can skip the error checking:
\snippet doc/src/snippets/code/src_qdbus_qdbusreply.cpp 1
However, if it does fail under those conditions, the value returned by QDBusReply::value() is
a default-constructed value. It may be indistinguishable from a valid return value.
QDBusReply objects are used for remote calls that have no output
arguments or return values (i.e., they have a "void" return
type). Use the isValid() function to test if the reply succeeded.
\sa QDBusMessage, QDBusInterface
*/
/*!
\fn QDBusReply::QDBusReply(const QDBusMessage &reply)
Automatically construct a QDBusReply object from the reply message \a reply, extracting the
first return value from it if it is a success reply.
*/
/*!
\fn QDBusReply::QDBusReply(const QDBusPendingReply<T> &reply)
Constructs a QDBusReply object from the pending reply message, \a reply.
*/
/*!
\fn QDBusReply::QDBusReply(const QDBusPendingCall &pcall)
Automatically construct a QDBusReply object from the asynchronous
pending call \a pcall. If the call isn't finished yet, QDBusReply
will call QDBusPendingCall::waitForFinished(), which is a blocking
operation.
If the return types patch, QDBusReply will extract the first
return argument from the reply.
*/
/*!
\fn QDBusReply::QDBusReply(const QDBusError &error)
Constructs an error reply from the D-Bus error code given by \a error.
*/
/*!
\fn QDBusReply::operator=(const QDBusReply &other)
Makes this object be a copy of the object \a other.
*/
/*!
\fn QDBusReply::operator=(const QDBusError &error)
Sets this object to contain the error code given by \a error. You
can later access it with error().
*/
/*!
\fn QDBusReply::operator=(const QDBusMessage &message)
Makes this object contain the reply specified by message \a
message. If \a message is an error message, this function will
copy the error code and message into this object
If \a message is a standard reply message and contains at least
one parameter, it will be copied into this object, as long as it
is of the correct type. If it's not of the same type as this
QDBusError object, this function will instead set an error code
indicating a type mismatch.
*/
/*!
\fn QDBusReply::operator=(const QDBusPendingCall &pcall)
Makes this object contain the reply specified by the pending
asynchronous call \a pcall. If the call is not finished yet, this
function will call QDBusPendingCall::waitForFinished() to block
until the reply arrives.
If \a pcall finishes with an error message, this function will
copy the error code and message into this object
If \a pcall finished with a standard reply message and contains at
least one parameter, it will be copied into this object, as long
as it is of the correct type. If it's not of the same type as this
QDBusError object, this function will instead set an error code
indicating a type mismatch.
*/
/*!
\fn bool QDBusReply::isValid() const
Returns true if no error occurred; otherwise, returns false.
\sa error()
*/
/*!
\fn QDBusReply::error()
Returns the error code that was returned from the remote function call. If the remote call did
not return an error (i.e., if it succeeded), then the QDBusError object that is returned will
not be a valid error code (QDBusError::isValid() will return false).
\sa isValid()
*/
/*!
\fn QDBusReply::value() const
Returns the remote function's calls return value. If the remote call returned with an error,
the return value of this function is undefined and may be undistinguishable from a valid return
value.
This function is not available if the remote call returns \c void.
*/
/*!
\fn QDBusReply::operator Type() const
Returns the same as value().
This function is not available if the remote call returns \c void.
*/
/*!
\internal
Fills in the QDBusReply data \a error and \a data from the reply message \a reply.
*/
void qDBusReplyFill(const QDBusMessage &reply, QDBusError &error, QVariant &data)
{
error = reply;
if (error.isValid()) {
data = QVariant(); // clear it
return;
}
if (reply.arguments().count() >= 1 && reply.arguments().at(0).userType() == data.userType()) {
data = reply.arguments().at(0);
return;
}
const char *expectedSignature = QDBusMetaType::typeToSignature(data.userType());
const char *receivedType = 0;
QByteArray receivedSignature;
if (reply.arguments().count() >= 1) {
if (reply.arguments().at(0).userType() == QDBusMetaTypeId::argument) {
// compare signatures instead
QDBusArgument arg = qvariant_cast<QDBusArgument>(reply.arguments().at(0));
receivedSignature = arg.currentSignature().toLatin1();
if (receivedSignature == expectedSignature) {
// matched. Demarshall it
QDBusMetaType::demarshall(arg, data.userType(), data.data());
return;
}
} else {
// not an argument and doesn't match?
int type = reply.arguments().at(0).userType();
receivedType = QVariant::typeToName(QVariant::Type(type));
receivedSignature = QDBusMetaType::typeToSignature(type);
}
}
// error
if (receivedSignature.isEmpty())
receivedSignature = "no signature";
QString errorMsg;
if (receivedType) {
errorMsg = QString::fromLatin1("Unexpected reply signature: got \"%1\" (%4), "
"expected \"%2\" (%3)")
.arg(QLatin1String(receivedSignature),
QLatin1String(expectedSignature),
QLatin1String(data.typeName()),
QLatin1String(receivedType));
} else {
errorMsg = QString::fromLatin1("Unexpected reply signature: got \"%1\", "
"expected \"%2\" (%3)")
.arg(QLatin1String(receivedSignature),
QLatin1String(expectedSignature),
QLatin1String(data.typeName()));
}
error = QDBusError(QDBusError::InvalidSignature, errorMsg);
data = QVariant(); // clear it
}
QT_END_NAMESPACE
#endif // QT_NO_DBUS
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