Source code

Revision control

Other Tools

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */
/* Helpers to manipulate integer types that don't fit in TypeTraits.h */
#ifndef mozilla_IntegerTypeTraits_h
#define mozilla_IntegerTypeTraits_h
#include <stddef.h>
#include <stdint.h>
#include <type_traits>
namespace mozilla {
namespace detail {
/**
* StdintTypeForSizeAndSignedness returns the stdint integer type
* of given size (can be 1, 2, 4 or 8) and given signedness
* (false means unsigned, true means signed).
*/
template <size_t Size, bool Signedness>
struct StdintTypeForSizeAndSignedness;
template <>
struct StdintTypeForSizeAndSignedness<1, true> {
typedef int8_t Type;
};
template <>
struct StdintTypeForSizeAndSignedness<1, false> {
typedef uint8_t Type;
};
template <>
struct StdintTypeForSizeAndSignedness<2, true> {
typedef int16_t Type;
};
template <>
struct StdintTypeForSizeAndSignedness<2, false> {
typedef uint16_t Type;
};
template <>
struct StdintTypeForSizeAndSignedness<4, true> {
typedef int32_t Type;
};
template <>
struct StdintTypeForSizeAndSignedness<4, false> {
typedef uint32_t Type;
};
template <>
struct StdintTypeForSizeAndSignedness<8, true> {
typedef int64_t Type;
};
template <>
struct StdintTypeForSizeAndSignedness<8, false> {
typedef uint64_t Type;
};
} // namespace detail
template <size_t Size>
struct UnsignedStdintTypeForSize
: detail::StdintTypeForSizeAndSignedness<Size, false> {};
template <size_t Size>
struct SignedStdintTypeForSize
: detail::StdintTypeForSizeAndSignedness<Size, true> {};
template <typename IntegerType>
struct PositionOfSignBit {
static_assert(std::is_integral_v<IntegerType>,
"PositionOfSignBit is only for integral types");
// 8 here should be CHAR_BIT from limits.h, but the world has moved on.
static const size_t value = 8 * sizeof(IntegerType) - 1;
};
} // namespace mozilla
#endif // mozilla_IntegerTypeTraits_h