xref: /freebsd/contrib/llvm-project/libcxx/include/cstddef (revision 1db9f3b21e39176dd5b67cf8ac378633b172463e)
1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_CSTDDEF
11#define _LIBCPP_CSTDDEF
12
13/*
14    cstddef synopsis
15
16Macros:
17
18    offsetof(type,member-designator)
19    NULL
20
21namespace std
22{
23
24Types:
25
26    ptrdiff_t
27    size_t
28    max_align_t // C++11
29    nullptr_t
30    byte // C++17
31
32}  // std
33
34*/
35
36#include <__assert> // all public C++ headers provide the assertion handler
37#include <__config>
38#include <__type_traits/enable_if.h>
39#include <__type_traits/integral_constant.h>
40#include <__type_traits/is_integral.h>
41#include <version>
42
43#include <stddef.h>
44
45#ifndef _LIBCPP_STDDEF_H
46#   error <cstddef> tried including <stddef.h> but didn't find libc++'s <stddef.h> header. \
47          This usually means that your header search paths are not configured properly. \
48          The header search paths should contain the C++ Standard Library headers before \
49          any C Standard Library, and you are probably using compiler flags that make that \
50          not be the case.
51#endif
52
53#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
54#  pragma GCC system_header
55#endif
56
57_LIBCPP_BEGIN_NAMESPACE_STD
58
59using ::nullptr_t;
60using ::ptrdiff_t _LIBCPP_USING_IF_EXISTS;
61using ::size_t _LIBCPP_USING_IF_EXISTS;
62
63#if !defined(_LIBCPP_CXX03_LANG)
64using ::max_align_t _LIBCPP_USING_IF_EXISTS;
65#endif
66
67_LIBCPP_END_NAMESPACE_STD
68
69#if _LIBCPP_STD_VER >= 17
70namespace std // purposefully not versioned
71{
72enum class byte : unsigned char {};
73
74_LIBCPP_HIDE_FROM_ABI inline constexpr byte operator|(byte __lhs, byte __rhs) noexcept {
75  return static_cast<byte>(
76      static_cast<unsigned char>(static_cast<unsigned int>(__lhs) | static_cast<unsigned int>(__rhs)));
77}
78
79_LIBCPP_HIDE_FROM_ABI inline constexpr byte& operator|=(byte& __lhs, byte __rhs) noexcept {
80  return __lhs = __lhs | __rhs;
81}
82
83_LIBCPP_HIDE_FROM_ABI inline constexpr byte operator&(byte __lhs, byte __rhs) noexcept {
84  return static_cast<byte>(
85      static_cast<unsigned char>(static_cast<unsigned int>(__lhs) & static_cast<unsigned int>(__rhs)));
86}
87
88_LIBCPP_HIDE_FROM_ABI inline constexpr byte& operator&=(byte& __lhs, byte __rhs) noexcept {
89  return __lhs = __lhs & __rhs;
90}
91
92_LIBCPP_HIDE_FROM_ABI inline constexpr byte operator^(byte __lhs, byte __rhs) noexcept {
93  return static_cast<byte>(
94      static_cast<unsigned char>(static_cast<unsigned int>(__lhs) ^ static_cast<unsigned int>(__rhs)));
95}
96
97_LIBCPP_HIDE_FROM_ABI inline constexpr byte& operator^=(byte& __lhs, byte __rhs) noexcept {
98  return __lhs = __lhs ^ __rhs;
99}
100
101_LIBCPP_HIDE_FROM_ABI inline constexpr byte operator~(byte __b) noexcept {
102  return static_cast<byte>(static_cast<unsigned char>(~static_cast<unsigned int>(__b)));
103}
104
105template <class _Integer, __enable_if_t<is_integral<_Integer>::value, int> = 0>
106_LIBCPP_HIDE_FROM_ABI constexpr byte& operator<<=(byte& __lhs, _Integer __shift) noexcept {
107  return __lhs = __lhs << __shift;
108}
109
110template <class _Integer, __enable_if_t<is_integral<_Integer>::value, int> = 0>
111_LIBCPP_HIDE_FROM_ABI constexpr byte operator<<(byte __lhs, _Integer __shift) noexcept {
112  return static_cast<byte>(static_cast<unsigned char>(static_cast<unsigned int>(__lhs) << __shift));
113}
114
115template <class _Integer, __enable_if_t<is_integral<_Integer>::value, int> = 0>
116_LIBCPP_HIDE_FROM_ABI constexpr byte& operator>>=(byte& __lhs, _Integer __shift) noexcept {
117  return __lhs = __lhs >> __shift;
118}
119
120template <class _Integer, __enable_if_t<is_integral<_Integer>::value, int> = 0>
121_LIBCPP_HIDE_FROM_ABI constexpr byte operator>>(byte __lhs, _Integer __shift) noexcept {
122  return static_cast<byte>(static_cast<unsigned char>(static_cast<unsigned int>(__lhs) >> __shift));
123}
124
125template <class _Integer, __enable_if_t<is_integral<_Integer>::value, int> = 0>
126_LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr _Integer to_integer(byte __b) noexcept {
127  return static_cast<_Integer>(__b);
128}
129
130} // namespace std
131
132#endif
133
134#endif // _LIBCPP_CSTDDEF
135