summaryrefslogtreecommitdiffstats
path: root/src/corelib/global/qendian_p.h
blob: c830e65b541b203039d9bc8c5644acf5f8e6d150 (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
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
/****************************************************************************
**
** Copyright (C) 2017 The Qt Company Ltd.
** 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 QENDIAN_P_H
#define QENDIAN_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/qendian.h>

QT_BEGIN_NAMESPACE

// Note if using multiple of these bitfields in a union; the underlying storage type must
// match. Since we always use an unsigned storage type, unsigned and signed versions may
// be used together, but different bit-widths may not.
template<class S, int pos, int width>
class QSpecialIntegerBitfield
{
protected:
    typedef typename S::StorageType T;
    typedef typename std::make_unsigned<T>::type UT;

    static Q_DECL_CONSTEXPR UT mask()
    {
        return ((UT(1) << width) - 1) << pos;
    }
public:
    // FIXME: val is public until qtdeclarative is fixed to not access it directly.
    UT val;

    QSpecialIntegerBitfield &operator =(T t)
    {
        UT i = S::fromSpecial(val);
        i &= ~mask();
        i |= (UT(t) << pos) & mask();
        val  = S::toSpecial(i);
        return *this;
    }
    operator T() const
    {
        if (std::is_signed<T>::value) {
            UT i = S::fromSpecial(val);
            i <<= (sizeof(T) * 8) - width - pos;
            T t = T(i);
            t >>= (sizeof(T) * 8) - width;
            return t;
        }
        return (S::fromSpecial(val) & mask()) >> pos;
    }

    bool operator !() const { return !(val & S::toSpecial(mask())); }
    bool operator ==(QSpecialIntegerBitfield<S, pos, width> i) const
    {   return ((val ^ i.val) & S::toSpecial(mask())) == 0; }
    bool operator !=(QSpecialIntegerBitfield<S, pos, width> i) const
    {   return ((val ^ i.val) & S::toSpecial(mask())) != 0; }

    QSpecialIntegerBitfield &operator +=(T i)
    {   return (*this = (T(*this) + i)); }
    QSpecialIntegerBitfield &operator -=(T i)
    {   return (*this = (T(*this) - i)); }
    QSpecialIntegerBitfield &operator *=(T i)
    {   return (*this = (T(*this) * i)); }
    QSpecialIntegerBitfield &operator /=(T i)
    {   return (*this = (T(*this) / i)); }
    QSpecialIntegerBitfield &operator %=(T i)
    {   return (*this = (T(*this) % i)); }
    QSpecialIntegerBitfield &operator |=(T i)
    {   return (*this = (T(*this) | i)); }
    QSpecialIntegerBitfield &operator &=(T i)
    {   return (*this = (T(*this) & i)); }
    QSpecialIntegerBitfield &operator ^=(T i)
    {   return (*this = (T(*this) ^ i)); }
    QSpecialIntegerBitfield &operator >>=(T i)
    {   return (*this = (T(*this) >> i)); }
    QSpecialIntegerBitfield &operator <<=(T i)
    {   return (*this = (T(*this) << i)); }
};

template<typename T, int pos, int width>
using QLEIntegerBitfield = QSpecialIntegerBitfield<QLittleEndianStorageType<T>, pos, width>;

template<typename T, int pos, int width>
using QBEIntegerBitfield = QSpecialIntegerBitfield<QBigEndianStorageType<T>, pos, width>;

template<int pos, int width>
using qint32_le_bitfield = QLEIntegerBitfield<int, pos, width>;
template<int pos, int width>
using quint32_le_bitfield = QLEIntegerBitfield<uint, pos, width>;
template<int pos, int width>
using qint32_be_bitfield = QBEIntegerBitfield<int, pos, width>;
template<int pos, int width>
using quint32_be_bitfield = QBEIntegerBitfield<uint, pos, width>;


QT_END_NAMESPACE

#endif // QENDIAN_P_H