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 <stddef.h>
39#include <version>
40
41#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
42#  pragma GCC system_header
43#endif
44
45_LIBCPP_BEGIN_NAMESPACE_STD
46
47using ::nullptr_t;
48using ::ptrdiff_t _LIBCPP_USING_IF_EXISTS;
49using ::size_t _LIBCPP_USING_IF_EXISTS;
50
51#if !defined(_LIBCPP_CXX03_LANG)
52using ::max_align_t _LIBCPP_USING_IF_EXISTS;
53#endif
54
55template <class _Tp> struct __libcpp_is_integral                     { enum { value = 0 }; };
56template <>          struct __libcpp_is_integral<bool>               { enum { value = 1 }; };
57template <>          struct __libcpp_is_integral<char>               { enum { value = 1 }; };
58template <>          struct __libcpp_is_integral<signed char>        { enum { value = 1 }; };
59template <>          struct __libcpp_is_integral<unsigned char>      { enum { value = 1 }; };
60#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
61template <>          struct __libcpp_is_integral<wchar_t>            { enum { value = 1 }; };
62#endif
63#ifndef _LIBCPP_HAS_NO_CHAR8_T
64template <>          struct __libcpp_is_integral<char8_t>            { enum { value = 1 }; };
65#endif
66#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
67template <>          struct __libcpp_is_integral<char16_t>           { enum { value = 1 }; };
68template <>          struct __libcpp_is_integral<char32_t>           { enum { value = 1 }; };
69#endif
70template <>          struct __libcpp_is_integral<short>              { enum { value = 1 }; };
71template <>          struct __libcpp_is_integral<unsigned short>     { enum { value = 1 }; };
72template <>          struct __libcpp_is_integral<int>                { enum { value = 1 }; };
73template <>          struct __libcpp_is_integral<unsigned int>       { enum { value = 1 }; };
74template <>          struct __libcpp_is_integral<long>               { enum { value = 1 }; };
75template <>          struct __libcpp_is_integral<unsigned long>      { enum { value = 1 }; };
76template <>          struct __libcpp_is_integral<long long>          { enum { value = 1 }; };
77template <>          struct __libcpp_is_integral<unsigned long long> { enum { value = 1 }; };
78#ifndef _LIBCPP_HAS_NO_INT128
79template <>          struct __libcpp_is_integral<__int128_t>         { enum { value = 1 }; };
80template <>          struct __libcpp_is_integral<__uint128_t>        { enum { value = 1 }; };
81#endif
82
83_LIBCPP_END_NAMESPACE_STD
84
85#if _LIBCPP_STD_VER > 14
86namespace std  // purposefully not versioned
87{
88enum class byte : unsigned char {};
89
90
91template <bool> struct __enable_if_integral_imp {};
92template <> struct __enable_if_integral_imp<true> { using type = byte; };
93template <class _Tp> using _EnableByteOverload = typename __enable_if_integral_imp<__libcpp_is_integral<_Tp>::value>::type;
94
95constexpr byte  operator| (byte  __lhs, byte __rhs) noexcept
96{
97    return static_cast<byte>(
98      static_cast<unsigned char>(
99         static_cast<unsigned int>(__lhs) | static_cast<unsigned int>(__rhs)
100    ));
101}
102
103constexpr byte& operator|=(byte& __lhs, byte __rhs) noexcept
104{ return __lhs = __lhs | __rhs; }
105
106constexpr byte  operator& (byte  __lhs, byte __rhs) noexcept
107{
108    return static_cast<byte>(
109      static_cast<unsigned char>(
110         static_cast<unsigned int>(__lhs) & static_cast<unsigned int>(__rhs)
111    ));
112}
113
114constexpr byte& operator&=(byte& __lhs, byte __rhs) noexcept
115{ return __lhs = __lhs & __rhs; }
116
117constexpr byte  operator^ (byte  __lhs, byte __rhs) noexcept
118{
119    return static_cast<byte>(
120      static_cast<unsigned char>(
121         static_cast<unsigned int>(__lhs) ^ static_cast<unsigned int>(__rhs)
122    ));
123}
124
125constexpr byte& operator^=(byte& __lhs, byte __rhs) noexcept
126{ return __lhs = __lhs ^ __rhs; }
127
128constexpr byte  operator~ (byte __b) noexcept
129{
130    return static_cast<byte>(
131      static_cast<unsigned char>(
132        ~static_cast<unsigned int>(__b)
133    ));
134}
135template <class _Integer>
136  constexpr _EnableByteOverload<_Integer> &
137  operator<<=(byte& __lhs, _Integer __shift) noexcept
138  { return __lhs = __lhs << __shift; }
139
140template <class _Integer>
141  constexpr _EnableByteOverload<_Integer>
142  operator<< (byte  __lhs, _Integer __shift) noexcept
143  { return static_cast<byte>(static_cast<unsigned char>(static_cast<unsigned int>(__lhs) << __shift)); }
144
145template <class _Integer>
146  constexpr _EnableByteOverload<_Integer> &
147  operator>>=(byte& __lhs, _Integer __shift) noexcept
148  { return __lhs = __lhs >> __shift; }
149
150template <class _Integer>
151  constexpr _EnableByteOverload<_Integer>
152  operator>> (byte  __lhs, _Integer __shift) noexcept
153  { return static_cast<byte>(static_cast<unsigned char>(static_cast<unsigned int>(__lhs) >> __shift)); }
154
155template <class _Integer, class = _EnableByteOverload<_Integer> >
156  _LIBCPP_NODISCARD_EXT constexpr _Integer
157  to_integer(byte __b) noexcept { return static_cast<_Integer>(__b); }
158
159} // namespace std
160
161#endif
162
163#endif // _LIBCPP_CSTDDEF
164