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39 | |
40 | #ifndef QENDIAN_P_H |
41 | #define QENDIAN_P_H |
42 | |
43 | // |
44 | // W A R N I N G |
45 | // ------------- |
46 | // |
47 | // This file is not part of the Qt API. It exists purely as an |
48 | // implementation detail. This header file may change from version to |
49 | // version without notice, or even be removed. |
50 | // |
51 | // We mean it. |
52 | // |
53 | |
54 | #include <QtCore/qendian.h> |
55 | |
56 | QT_BEGIN_NAMESPACE |
57 | |
58 | // Note if using multiple of these bitfields in a union; the underlying storage type must |
59 | // match. Since we always use an unsigned storage type, unsigned and signed versions may |
60 | // be used together, but different bit-widths may not. |
61 | template<class S, int pos, int width> |
62 | class QSpecialIntegerBitfield |
63 | { |
64 | protected: |
65 | typedef typename S::StorageType T; |
66 | typedef typename std::make_unsigned<T>::type UT; |
67 | |
68 | static Q_DECL_CONSTEXPR UT mask() |
69 | { |
70 | return ((UT(1) << width) - 1) << pos; |
71 | } |
72 | public: |
73 | // FIXME: val is public until qtdeclarative is fixed to not access it directly. |
74 | UT val; |
75 | |
76 | QSpecialIntegerBitfield &operator =(T t) |
77 | { |
78 | UT i = S::fromSpecial(val); |
79 | i &= ~mask(); |
80 | i |= (UT(t) << pos) & mask(); |
81 | val = S::toSpecial(i); |
82 | return *this; |
83 | } |
84 | operator T() const |
85 | { |
86 | if (std::is_signed<T>::value) { |
87 | UT i = S::fromSpecial(val); |
88 | i <<= (sizeof(T) * 8) - width - pos; |
89 | T t = T(i); |
90 | t >>= (sizeof(T) * 8) - width; |
91 | return t; |
92 | } |
93 | return (S::fromSpecial(val) & mask()) >> pos; |
94 | } |
95 | |
96 | bool operator !() const { return !(val & S::toSpecial(mask())); } |
97 | bool operator ==(QSpecialIntegerBitfield<S, pos, width> i) const |
98 | { return ((val ^ i.val) & S::toSpecial(mask())) == 0; } |
99 | bool operator !=(QSpecialIntegerBitfield<S, pos, width> i) const |
100 | { return ((val ^ i.val) & S::toSpecial(mask())) != 0; } |
101 | |
102 | QSpecialIntegerBitfield &operator +=(T i) |
103 | { return (*this = (T(*this) + i)); } |
104 | QSpecialIntegerBitfield &operator -=(T i) |
105 | { return (*this = (T(*this) - i)); } |
106 | QSpecialIntegerBitfield &operator *=(T i) |
107 | { return (*this = (T(*this) * i)); } |
108 | QSpecialIntegerBitfield &operator /=(T i) |
109 | { return (*this = (T(*this) / i)); } |
110 | QSpecialIntegerBitfield &operator %=(T i) |
111 | { return (*this = (T(*this) % i)); } |
112 | QSpecialIntegerBitfield &operator |=(T i) |
113 | { return (*this = (T(*this) | i)); } |
114 | QSpecialIntegerBitfield &operator &=(T i) |
115 | { return (*this = (T(*this) & i)); } |
116 | QSpecialIntegerBitfield &operator ^=(T i) |
117 | { return (*this = (T(*this) ^ i)); } |
118 | QSpecialIntegerBitfield &operator >>=(T i) |
119 | { return (*this = (T(*this) >> i)); } |
120 | QSpecialIntegerBitfield &operator <<=(T i) |
121 | { return (*this = (T(*this) << i)); } |
122 | }; |
123 | |
124 | template<typename T, int pos, int width> |
125 | using QLEIntegerBitfield = QSpecialIntegerBitfield<QLittleEndianStorageType<T>, pos, width>; |
126 | |
127 | template<typename T, int pos, int width> |
128 | using QBEIntegerBitfield = QSpecialIntegerBitfield<QBigEndianStorageType<T>, pos, width>; |
129 | |
130 | template<int pos, int width> |
131 | using qint32_le_bitfield = QLEIntegerBitfield<int, pos, width>; |
132 | template<int pos, int width> |
133 | using quint32_le_bitfield = QLEIntegerBitfield<uint, pos, width>; |
134 | template<int pos, int width> |
135 | using qint32_be_bitfield = QBEIntegerBitfield<int, pos, width>; |
136 | template<int pos, int width> |
137 | using quint32_be_bitfield = QBEIntegerBitfield<uint, pos, width>; |
138 | |
139 | |
140 | QT_END_NAMESPACE |
141 | |
142 | #endif // QENDIAN_P_H |
143 | |