1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
/****************************************************************************
**
** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the QtDBus module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL21$
** 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 Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/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 2.1 or version 3 as published by the Free
** Software Foundation and appearing in the file LICENSE.LGPLv21 and
** LICENSE.LGPLv3 included in the packaging of this file. Please review the
** following information to ensure the GNU Lesser General Public License
** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
** rights. These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qdbusmessage.h"
#include "qdbusconnection.h"
#include "qdbusabstractadaptor.h"
#include "qdbuscontext.h"
#include "qdbuscontext_p.h"
#ifndef QT_NO_DBUS
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
{Qt D-Bus XML compiler (qdbusxml2cpp)}.
QDBusContext is used by subclassing it from the objects being
exported using QDBusConnection::registerObject(). The following
example illustrates the usage:
\snippet 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 \c true if we are processing a D-Bus call. If this function
returns \c true, the rest of the functions in this class are
available.
Accessing those functions when this function returns \c 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 \c 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, Qt D-Bus will automatically generate a reply
back to the caller, if needed, as soon as the called slot returns.
If \a enable is true, Qt D-Bus 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 Qt D-Bus.
*/
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 Qt D-Bus.
*/
void QDBusContext::sendErrorReply(QDBusError::ErrorType type, const QString &msg) const
{
setDelayedReply(true);
connection().send(message().createErrorReply(type, msg));
}
QT_END_NAMESPACE
#endif // QT_NO_DBUS
|