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
201
202
203
204
|
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** 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 either Technology Preview License Agreement or the
** Beta Release License Agreement.
**
** 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 1.0, included in the file LGPL_EXCEPTION.txt in this
** package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at http://qt.nokia.com/contact.
** $QT_END_LICENSE$
**
****************************************************************************/
#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
|
