summaryrefslogtreecommitdiffstats
path: root/src/corelib/kernel/qvariant_p.h
blob: 18fc0fbf80e1772fffd468fcfba33a00b98809bc (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
104
105
106
107
108
/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Copyright (C) 2016 Intel Corporation.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** 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 https://www.qt.io/terms-conditions. For further
** information use the contact form at https://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 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QVARIANT_P_H
#define QVARIANT_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include <QtCore/qglobal.h>
#include <QtCore/qvariant.h>
#include <QtCore/private/qmetatype_p.h>

QT_BEGIN_NAMESPACE

template<typename T>
struct QVariantIntegrator
{
    static constexpr bool CanUseInternalSpace = sizeof(T) <= sizeof(QVariant::Private::Data);
    typedef std::integral_constant<bool, CanUseInternalSpace> CanUseInternalSpace_t;
};
static_assert(QVariantIntegrator<double>::CanUseInternalSpace);
static_assert(QVariantIntegrator<long int>::CanUseInternalSpace);
static_assert(QVariantIntegrator<qulonglong>::CanUseInternalSpace);

template <typename T>
inline const T *v_cast(const QVariant::Private *d, T * = nullptr)
{
    return !QVariantIntegrator<T>::CanUseInternalSpace
            ? static_cast<const T *>(d->data.shared->data())
            : static_cast<const T *>(static_cast<const void *>(&d->data));
}

template <typename T>
inline T *v_cast(QVariant::Private *d, T * = nullptr)
{
    return !QVariantIntegrator<T>::CanUseInternalSpace
            ? static_cast<T *>(d->data.shared->data())
            : static_cast<T *>(static_cast<void *>(&d->data));
}

template <class T>
inline void v_construct(QVariant::Private *x, const T &t)
{
    if constexpr (QVariantIntegrator<T>::CanUseInternalSpace) {
        new (&x->data) T(t);
        x->is_shared = false;
    } else {
        x->data.shared = QVariant::PrivateShared::create(QMetaType::fromType<T>());
        new (x->data.shared->data()) T(t);
        x->is_shared = true;
    }
}

Q_CORE_EXPORT const QVariant::Handler *qcoreVariantHandler();

namespace QVariantPrivate {
Q_CORE_EXPORT void registerHandler(const int /* Modules::Names */ name, const QVariant::Handler *handler);
}

QT_END_NAMESPACE

#endif // QVARIANT_P_H