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Diffstat (limited to 'src/corelib/global/qendian_p.h')
| -rw-r--r-- | src/corelib/global/qendian_p.h | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/src/corelib/global/qendian_p.h b/src/corelib/global/qendian_p.h new file mode 100644 index 0000000000..c830e65b54 --- /dev/null +++ b/src/corelib/global/qendian_p.h @@ -0,0 +1,142 @@ +/**************************************************************************** +** +** 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 |