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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-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP___SYSTEM_ERROR_ERROR_CONDITION_H11#define _LIBCPP___SYSTEM_ERROR_ERROR_CONDITION_H12 13#include <__compare/ordering.h>14#include <__config>15#include <__functional/hash.h>16#include <__functional/unary_function.h>17#include <__system_error/errc.h>18#include <__system_error/error_category.h>19#include <string>20 21#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)22# pragma GCC system_header23#endif24 25_LIBCPP_BEGIN_NAMESPACE_STD26 27template <class _Tp>28struct is_error_condition_enum : public false_type {};29 30#if _LIBCPP_STD_VER >= 1731template <class _Tp>32inline constexpr bool is_error_condition_enum_v = is_error_condition_enum<_Tp>::value;33#endif34 35template <>36struct is_error_condition_enum<errc> : true_type {};37 38#ifdef _LIBCPP_CXX03_LANG39template <>40struct is_error_condition_enum<errc::__lx> : true_type {};41#endif42 43namespace __adl_only {44// Those cause ADL to trigger but they are not viable candidates,45// so they are never actually selected.46void make_error_condition() = delete;47} // namespace __adl_only48 49class _LIBCPP_EXPORTED_FROM_ABI error_condition {50 int __val_;51 const error_category* __cat_;52 53public:54 _LIBCPP_HIDE_FROM_ABI error_condition() _NOEXCEPT : __val_(0), __cat_(&generic_category()) {}55 56 _LIBCPP_HIDE_FROM_ABI error_condition(int __val, const error_category& __cat) _NOEXCEPT57 : __val_(__val),58 __cat_(&__cat) {}59 60 template <class _Ep, __enable_if_t<is_error_condition_enum<_Ep>::value, int> = 0>61 _LIBCPP_HIDE_FROM_ABI error_condition(_Ep __e) _NOEXCEPT {62 using __adl_only::make_error_condition;63 *this = make_error_condition(__e);64 }65 66 _LIBCPP_HIDE_FROM_ABI void assign(int __val, const error_category& __cat) _NOEXCEPT {67 __val_ = __val;68 __cat_ = &__cat;69 }70 71 template <class _Ep, __enable_if_t<is_error_condition_enum<_Ep>::value, int> = 0>72 _LIBCPP_HIDE_FROM_ABI error_condition& operator=(_Ep __e) _NOEXCEPT {73 using __adl_only::make_error_condition;74 *this = make_error_condition(__e);75 return *this;76 }77 78 _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT {79 __val_ = 0;80 __cat_ = &generic_category();81 }82 83 _LIBCPP_HIDE_FROM_ABI int value() const _NOEXCEPT { return __val_; }84 85 _LIBCPP_HIDE_FROM_ABI const error_category& category() const _NOEXCEPT { return *__cat_; }86 string message() const;87 88 _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return __val_ != 0; }89};90 91inline _LIBCPP_HIDE_FROM_ABI error_condition make_error_condition(errc __e) _NOEXCEPT {92 return error_condition(static_cast<int>(__e), generic_category());93}94 95inline _LIBCPP_HIDE_FROM_ABI bool operator==(const error_condition& __x, const error_condition& __y) _NOEXCEPT {96 return __x.category() == __y.category() && __x.value() == __y.value();97}98 99#if _LIBCPP_STD_VER <= 17100 101inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const error_condition& __x, const error_condition& __y) _NOEXCEPT {102 return !(__x == __y);103}104 105inline _LIBCPP_HIDE_FROM_ABI bool operator<(const error_condition& __x, const error_condition& __y) _NOEXCEPT {106 return __x.category() < __y.category() || (__x.category() == __y.category() && __x.value() < __y.value());107}108 109#else // _LIBCPP_STD_VER <= 17110 111inline _LIBCPP_HIDE_FROM_ABI strong_ordering112operator<=>(const error_condition& __x, const error_condition& __y) noexcept {113 if (auto __c = __x.category() <=> __y.category(); __c != 0)114 return __c;115 return __x.value() <=> __y.value();116}117 118#endif // _LIBCPP_STD_VER <= 17119 120template <>121struct hash<error_condition> : public __unary_function<error_condition, size_t> {122 _LIBCPP_HIDE_FROM_ABI size_t operator()(const error_condition& __ec) const _NOEXCEPT {123 return static_cast<size_t>(__ec.value());124 }125};126 127_LIBCPP_END_NAMESPACE_STD128 129#endif // _LIBCPP___SYSTEM_ERROR_ERROR_CONDITION_H130