summaryrefslogtreecommitdiffstats
path: root/src/plugins/platforms/cocoa/qcocoaintrospection.mm
blob: c8e7d9d39e61e33e8e342543f84740825c3d7506 (plain)
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
/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the plugins 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 The Qt Company. For licensing terms
** and conditions see http://www.qt.io/terms-conditions. For further
** information use the contact form at http://www.qt.io/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.
**
** As a special exception, The Qt Company gives you certain additional
** rights. These rights are described in The Qt Company LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** $QT_END_LICENSE$
**
****************************************************************************/

/****************************************************************************
**
** Copyright (c) 2007-2008, Apple, Inc.
**
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are met:
**
**   * Redistributions of source code must retain the above copyright notice,
**     this list of conditions and the following disclaimer.
**
**   * Redistributions in binary form must reproduce the above copyright notice,
**     this list of conditions and the following disclaimer in the documentation
**     and/or other materials provided with the distribution.
**
**   * Neither the name of Apple, Inc. nor the names of its contributors
**     may be used to endorse or promote products derived from this software
**     without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
** CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
** EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
** PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
** PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
** LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
** NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
** SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**
****************************************************************************/

#include "qcocoaintrospection.h"

QT_BEGIN_NAMESPACE

void qt_cocoa_change_implementation(Class baseClass, SEL originalSel, Class proxyClass, SEL replacementSel, SEL backupSel)
{
    // The following code replaces the _implementation_ for the selector we want to hack
    // (originalSel) with the implementation found in proxyClass. Then it creates
    // a new 'backup' method inside baseClass containing the old, original,
    // implementation (fakeSel). You can let the proxy implementation of originalSel
    // call fakeSel if needed (similar approach to calling a super class implementation).
    // fakeSel must also be implemented in proxyClass, as the signature is used
    // as template for the method one we add into baseClass.
    // NB: You will typically never create any instances of proxyClass; we use it
    // only for stealing its contents and put it into baseClass.
    if (!replacementSel)
        replacementSel = originalSel;

    Method originalMethod = class_getInstanceMethod(baseClass, originalSel);
    Method replacementMethod = class_getInstanceMethod(proxyClass, replacementSel);
    IMP originalImp = method_setImplementation(originalMethod, method_getImplementation(replacementMethod));

    if (backupSel) {
        Method backupMethod = class_getInstanceMethod(proxyClass, backupSel);
        class_addMethod(baseClass, backupSel, originalImp, method_getTypeEncoding(backupMethod));
    }
}

void qt_cocoa_change_back_implementation(Class baseClass, SEL originalSel, SEL backupSel)
{
    Method originalMethod = class_getInstanceMethod(baseClass, originalSel);
    Method backupMethodInBaseClass = class_getInstanceMethod(baseClass, backupSel);
    method_setImplementation(originalMethod, method_getImplementation(backupMethodInBaseClass));
}

QT_END_NAMESPACE