1#ifndef BOOST_SYSTEM_DETAIL_SYSTEM_CATEGORY_HPP_INCLUDED
2#define BOOST_SYSTEM_DETAIL_SYSTEM_CATEGORY_HPP_INCLUDED
3
4// Copyright Beman Dawes 2006, 2007
5// Copyright Christoper Kohlhoff 2007
6// Copyright Peter Dimov 2017, 2018
7//
8// Distributed under the Boost Software License, Version 1.0. (See accompanying
9// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
10//
11// See library home page at http://www.boost.org/libs/system
12
13#include <boost/system/detail/error_category.hpp>
14#include <boost/system/detail/config.hpp>
15#include <boost/config.hpp>
16
17namespace boost
18{
19
20namespace system
21{
22
23namespace detail
24{
25
26// system_error_category
27
28#if ( defined( BOOST_GCC ) && BOOST_GCC >= 40600 ) || defined( BOOST_CLANG )
29#pragma GCC diagnostic push
30#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
31#endif
32
33class BOOST_SYMBOL_VISIBLE system_error_category: public error_category
34{
35public:
36
37 BOOST_SYSTEM_CONSTEXPR system_error_category() noexcept:
38 error_category( detail::system_category_id )
39 {
40 }
41
42 const char * name() const noexcept BOOST_OVERRIDE
43 {
44 return "system";
45 }
46
47 error_condition default_error_condition( int ev ) const noexcept BOOST_OVERRIDE;
48
49 std::string message( int ev ) const BOOST_OVERRIDE;
50 char const * message( int ev, char * buffer, std::size_t len ) const noexcept BOOST_OVERRIDE;
51};
52
53#if ( defined( BOOST_GCC ) && BOOST_GCC >= 40600 ) || defined( BOOST_CLANG )
54#pragma GCC diagnostic pop
55#endif
56
57} // namespace detail
58
59// system_category()
60
61#if defined(BOOST_SYSTEM_HAS_CONSTEXPR)
62
63namespace detail
64{
65
66template<class T> struct BOOST_SYMBOL_VISIBLE system_cat_holder
67{
68 static constexpr system_error_category instance{};
69};
70
71// Before C++17 it was mandatory to redeclare all static constexpr
72#if defined(BOOST_NO_CXX17_INLINE_VARIABLES)
73template<class T> constexpr system_error_category system_cat_holder<T>::instance;
74#endif
75
76} // namespace detail
77
78constexpr error_category const & system_category() noexcept
79{
80 return detail::system_cat_holder<void>::instance;
81}
82
83#else // #if defined(BOOST_SYSTEM_HAS_CONSTEXPR)
84
85#if !defined(__SUNPRO_CC) // trailing __global is not supported
86inline error_category const & system_category() noexcept BOOST_SYMBOL_VISIBLE;
87#endif
88
89inline error_category const & system_category() noexcept
90{
91 static const detail::system_error_category instance;
92 return instance;
93}
94
95#endif // #if defined(BOOST_SYSTEM_HAS_CONSTEXPR)
96
97// deprecated synonyms
98
99#ifdef BOOST_SYSTEM_ENABLE_DEPRECATED
100
101BOOST_SYSTEM_DEPRECATED("please use system_category()") inline const error_category & get_system_category() { return system_category(); }
102BOOST_SYSTEM_DEPRECATED("please use system_category()") static const error_category & native_ecat BOOST_ATTRIBUTE_UNUSED = system_category();
103
104#endif
105
106} // namespace system
107
108} // namespace boost
109
110#endif // #ifndef BOOST_SYSTEM_DETAIL_SYSTEM_CATEGORY_HPP_INCLUDED
111

source code of boost/libs/system/include/boost/system/detail/system_category.hpp