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+/* -*- 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; }
+
+ 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: */