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Diffstat (limited to 'include/o3tl/strong_int.hxx')
| -rw-r--r-- | include/o3tl/strong_int.hxx | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/include/o3tl/strong_int.hxx b/include/o3tl/strong_int.hxx new file mode 100644 index 0000000000..8210795589 --- /dev/null +++ b/include/o3tl/strong_int.hxx @@ -0,0 +1,156 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of the LibreOffice project. + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + * + * This file incorporates work covered by the following license notice: + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed + * with this work for additional information regarding copyright + * ownership. The ASF licenses this file to you under the Apache + * License, Version 2.0 (the "License"); you may not use this file + * except in compliance with the License. You may obtain a copy of + * the License at http://www.apache.org/licenses/LICENSE-2.0 . + */ + +#ifndef INCLUDED_O3TL_STRONG_INT_HXX +#define INCLUDED_O3TL_STRONG_INT_HXX + +#include <sal/config.h> +#include <limits> +#include <cassert> +#include <type_traits> + +namespace o3tl +{ + +#if !defined __COVERITY__ + +namespace detail { + +template<typename T1, typename T2> constexpr +typename std::enable_if< + std::is_signed<T1>::value && std::is_signed<T2>::value, bool>::type +isInRange(T2 value) { + return value >= std::numeric_limits<T1>::min() + && value <= std::numeric_limits<T1>::max(); +} + +template<typename T1, typename T2> constexpr +typename std::enable_if< + std::is_signed<T1>::value && std::is_unsigned<T2>::value, bool>::type +isInRange(T2 value) { + return value + <= static_cast<typename std::make_unsigned<T1>::type>( + std::numeric_limits<T1>::max()); +} + +template<typename T1, typename T2> constexpr +typename std::enable_if< + std::is_unsigned<T1>::value && std::is_signed<T2>::value, bool>::type +isInRange(T2 value) { + return value >= 0 + && (static_cast<typename std::make_unsigned<T2>::type>(value) + <= std::numeric_limits<T1>::max()); +} + +template<typename T1, typename T2> constexpr +typename std::enable_if< + std::is_unsigned<T1>::value && std::is_unsigned<T2>::value, bool>::type +isInRange(T2 value) { + return value <= std::numeric_limits<T1>::max(); +} + +} + +#endif + +/// +/// Wrap up an integer type so that we prevent accidental conversion to other integer types. +/// +/// e.g. +/// typedef o3tl::strong_int<unsigned, struct MyIntTag> MyInt; +/// +/// \param UNDERLYING_TYPE the underlying scalar type +/// \param PHANTOM_TYPE a type tag, used to distinguish this instantiation of the template +/// from other instantiations with the same UNDERLYING_TYPE. +/// +template <typename UNDERLYING_TYPE, typename PHANTOM_TYPE> +struct strong_int +{ +public: + template<typename T> explicit constexpr strong_int( + T value, + typename std::enable_if<std::is_integral<T>::value, int>::type = 0): + m_value(value) + { +#if !defined __COVERITY__ + // catch attempts to pass in out-of-range values early + assert(detail::isInRange<UNDERLYING_TYPE>(value) + && "out of range"); +#endif + } + strong_int() : m_value(0) {} + + explicit constexpr operator UNDERLYING_TYPE() const { return m_value; } + explicit operator bool() const { return m_value != 0; } + UNDERLYING_TYPE get() const { return m_value; } + + bool operator<(strong_int const & other) const { return m_value < other.m_value; } + bool operator<=(strong_int const & other) const { return m_value <= other.m_value; } + bool operator>(strong_int const & other) const { return m_value > other.m_value; } + bool operator>=(strong_int const & other) const { return m_value >= other.m_value; } + bool operator==(strong_int const & other) const { return m_value == other.m_value; } + bool operator!=(strong_int const & other) const { return m_value != other.m_value; } + strong_int& operator++() { ++m_value; return *this; } + strong_int operator++(int) { UNDERLYING_TYPE nOldValue = m_value; ++m_value; return strong_int(nOldValue); } + strong_int& operator--() { --m_value; return *this; } + strong_int operator--(int) { UNDERLYING_TYPE nOldValue = m_value; --m_value; return strong_int(nOldValue); } + strong_int& operator+=(strong_int const & other) { m_value += other.m_value; return *this; } + strong_int& operator-=(strong_int const & other) { m_value -= other.m_value; return *this; } + strong_int& operator%=(strong_int const & other) { m_value %= other.m_value; return *this; } + strong_int& operator*=(strong_int const & other) { m_value *= other.m_value; return *this; } + strong_int& operator/=(strong_int const & other) { m_value /= other.m_value; return *this; } + [[nodiscard]] + strong_int operator%(strong_int const & other) const { return strong_int(m_value % other.m_value); } + [[nodiscard]] + strong_int operator-() const { return strong_int(-m_value); } + [[nodiscard]] + strong_int operator*(strong_int const & other) const { return strong_int(m_value * other.m_value); } + [[nodiscard]] + strong_int operator/(strong_int const & other) const { return strong_int(m_value / other.m_value); } + + bool anyOf(strong_int v) const { + return *this == v; + } + + template<typename... Args> + bool anyOf(strong_int first, Args... args) const { + return *this == first || anyOf(args...); + } + +private: + UNDERLYING_TYPE m_value; +}; + +template <typename UT, typename PT> +strong_int<UT,PT> operator+(strong_int<UT,PT> const & lhs, strong_int<UT,PT> const & rhs) +{ + return strong_int<UT,PT>(lhs.get() + rhs.get()); +} + +template <typename UT, typename PT> +strong_int<UT,PT> operator-(strong_int<UT,PT> const & lhs, strong_int<UT,PT> const & rhs) +{ + return strong_int<UT,PT>(lhs.get() - rhs.get()); +} + +}; // namespace o3tl + +#endif /* INCLUDED_O3TL_STRONG_INT_HXX */ + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |