416 lines
22 KiB
C++
416 lines
22 KiB
C++
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/* Proposed SG14 status_code
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(C) 2018 - 2021 Niall Douglas <http://www.nedproductions.biz/> (5 commits)
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File Created: Feb 2018
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License in the accompanying file
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Licence.txt or at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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Distributed under the Boost Software License, Version 1.0.
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(See accompanying file Licence.txt or copy at
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http://www.boost.org/LICENSE_1_0.txt)
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*/
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_CONFIG_HPP
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#define BOOST_OUTCOME_SYSTEM_ERROR2_CONFIG_HPP
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// < 0.1 each
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#include <cassert>
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#include <cstddef> // for size_t
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#include <cstdlib> // for free
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// 0.22
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#include <type_traits>
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// 0.29
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#include <atomic>
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// 0.28 (0.15 of which is exception_ptr)
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#include <exception> // for std::exception
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// <new> includes <exception>, <exception> includes <new>
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#include <new>
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// 0.01
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#include <initializer_list>
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_HAVE_BIT_CAST
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#ifdef __has_include
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#if __has_include(<bit>) && (__cplusplus >= 202002L || _HAS_CXX20)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_HAVE_BIT_CAST 1
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#endif
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#elif __cplusplus >= 202002L
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#define BOOST_OUTCOME_SYSTEM_ERROR2_HAVE_BIT_CAST 1
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#endif
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_HAVE_BIT_CAST
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#define BOOST_OUTCOME_SYSTEM_ERROR2_HAVE_BIT_CAST 0
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#endif
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#endif
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#if BOOST_OUTCOME_SYSTEM_ERROR2_HAVE_BIT_CAST
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#include <bit>
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#if __cpp_lib_bit_cast < 201806L
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#undef BOOST_OUTCOME_SYSTEM_ERROR2_HAVE_BIT_CAST
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#define BOOST_OUTCOME_SYSTEM_ERROR2_HAVE_BIT_CAST 0
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#endif
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#endif
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_CONSTEXPR14
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#if defined(BOOST_OUTCOME_STANDARDESE_IS_IN_THE_HOUSE) || __cplusplus >= 201400 || _MSC_VER >= 1910 /* VS2017 */
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//! Defined to be `constexpr` when on C++ 14 or better compilers. Usually automatic, can be overriden.
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#define BOOST_OUTCOME_SYSTEM_ERROR2_CONSTEXPR14 constexpr
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#else
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#define BOOST_OUTCOME_SYSTEM_ERROR2_CONSTEXPR14
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#endif
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#endif
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_CONSTEXPR20
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#if defined(BOOST_OUTCOME_STANDARDESE_IS_IN_THE_HOUSE) || __cplusplus >= 202000 || _HAS_CXX20
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//! Defined to be `constexpr` when on C++ 20 or better compilers. Usually automatic, can be overriden.
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#define BOOST_OUTCOME_SYSTEM_ERROR2_CONSTEXPR20 constexpr
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#else
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#define BOOST_OUTCOME_SYSTEM_ERROR2_CONSTEXPR20
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#endif
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#endif
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN
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#if defined(BOOST_OUTCOME_STANDARDESE_IS_IN_THE_HOUSE) || (_HAS_CXX17 && _MSC_VER >= 1911 /* VS2017.3 */)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN [[noreturn]]
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#endif
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#endif
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#if !defined(BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN)
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#ifdef __has_cpp_attribute
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#if __has_cpp_attribute(noreturn)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN [[noreturn]]
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#endif
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#endif
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#endif
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#if !defined(BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN)
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#if defined(_MSC_VER)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN __declspec(noreturn)
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#elif defined(__GNUC__)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN __attribute__((__noreturn__))
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#else
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN
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#endif
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#endif
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// GCCs before 7 don't grok [[noreturn]] virtual functions, and warn annoyingly
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#if defined(__GNUC__) && !defined(__clang__) && __GNUC__ < 7
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#undef BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN
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#endif
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_NODISCARD
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#if defined(BOOST_OUTCOME_STANDARDESE_IS_IN_THE_HOUSE) || (_HAS_CXX17 && _MSC_VER >= 1911 /* VS2017.3 */)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NODISCARD [[nodiscard]]
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#endif
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#endif
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_NODISCARD
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#ifdef __has_cpp_attribute
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#if __has_cpp_attribute(nodiscard)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NODISCARD [[nodiscard]]
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#endif
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#elif defined(__clang__)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NODISCARD __attribute__((warn_unused_result))
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#elif defined(_MSC_VER)
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// _Must_inspect_result_ expands into this
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NODISCARD \
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__declspec("SAL_name" \
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"(" \
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"\"_Must_inspect_result_\"" \
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"," \
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"\"\"" \
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"," \
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"\"2\"" \
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")") __declspec("SAL_begin") __declspec("SAL_post") __declspec("SAL_mustInspect") __declspec("SAL_post") __declspec("SAL_checkReturn") __declspec("SAL_end")
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#endif
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#endif
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_NODISCARD
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NODISCARD
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#endif
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_TRIVIAL_ABI
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#if defined(BOOST_OUTCOME_STANDARDESE_IS_IN_THE_HOUSE) || (__clang_major__ >= 7 && !defined(__APPLE__))
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//! Defined to be `[[clang::trivial_abi]]` when on a new enough clang compiler. Usually automatic, can be overriden.
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TRIVIAL_ABI [[clang::trivial_abi]]
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#else
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TRIVIAL_ABI
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#endif
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#endif
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#if defined(__cpp_concepts) && !defined(BOOST_OUTCOME_SYSTEM_ERROR2_DISABLE_CONCEPTS_SUPPORT)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_GLUE(x, y) x y
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#define BOOST_OUTCOME_SYSTEM_ERROR2_RETURN_ARG_COUNT(_1_, _2_, _3_, _4_, _5_, _6_, _7_, _8_, count, ...) count
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#define BOOST_OUTCOME_SYSTEM_ERROR2_EXPAND_ARGS(args) BOOST_OUTCOME_SYSTEM_ERROR2_RETURN_ARG_COUNT args
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#define BOOST_OUTCOME_SYSTEM_ERROR2_COUNT_ARGS_MAX8(...) BOOST_OUTCOME_SYSTEM_ERROR2_EXPAND_ARGS((__VA_ARGS__, 8, 7, 6, 5, 4, 3, 2, 1, 0))
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#define BOOST_OUTCOME_SYSTEM_ERROR2_OVERLOAD_MACRO2(name, count) name##count
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#define BOOST_OUTCOME_SYSTEM_ERROR2_OVERLOAD_MACRO1(name, count) BOOST_OUTCOME_SYSTEM_ERROR2_OVERLOAD_MACRO2(name, count)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_OVERLOAD_MACRO(name, count) BOOST_OUTCOME_SYSTEM_ERROR2_OVERLOAD_MACRO1(name, count)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_CALL_OVERLOAD(name, ...) BOOST_OUTCOME_SYSTEM_ERROR2_GLUE(BOOST_OUTCOME_SYSTEM_ERROR2_OVERLOAD_MACRO(name, BOOST_OUTCOME_SYSTEM_ERROR2_COUNT_ARGS_MAX8(__VA_ARGS__)), (__VA_ARGS__))
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND8(a, b, c, d, e, f, g, h) a &&BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND7(b, c, d, e, f, g, h)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND7(a, b, c, d, e, f, g) a &&BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND6(b, c, d, e, f, g)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND6(a, b, c, d, e, f) a &&BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND5(b, c, d, e, f)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND5(a, b, c, d, e) a &&BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND4(b, c, d, e)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND4(a, b, c, d) a &&BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND3(b, c, d)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND3(a, b, c) a &&BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND2(b, c)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND2(a, b) a &&BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND1(b)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND1(a) a
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//! Expands into a && b && c && ...
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(...) requires BOOST_OUTCOME_SYSTEM_ERROR2_CALL_OVERLOAD(BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES_EXPAND, __VA_ARGS__)
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(...) template <__VA_ARGS__>
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TEXPR(...) \
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requires { (__VA_ARGS__); }
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(...) (__VA_ARGS__)
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#if !defined(_MSC_VER) || _MSC_FULL_VER >= 192400000 // VS 2019 16.3 is broken here
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#define BOOST_OUTCOME_SYSTEM_ERROR2_REQUIRES(...) requires(__VA_ARGS__)
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#else
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#define BOOST_OUTCOME_SYSTEM_ERROR2_REQUIRES(...)
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#endif
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#else
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(...) template <__VA_ARGS__
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(...) , __VA_ARGS__ >
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TEXPR(...) typename = decltype(__VA_ARGS__)
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#ifdef _MSC_VER
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// MSVC gives an error if every specialisation of a template is always ill-formed, so
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// the more powerful SFINAE form below causes pukeage :(
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(...) typename = typename std::enable_if<(__VA_ARGS__)>::type
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#else
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#define BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(...) typename std::enable_if<(__VA_ARGS__), bool>::type = true
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#endif
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#define BOOST_OUTCOME_SYSTEM_ERROR2_REQUIRES(...)
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#endif
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#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE
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//! The system_error2 namespace name.
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE system_error2
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//! Begins the system_error2 namespace.
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE_BEGIN \
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namespace system_error2 \
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{
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//! Ends the system_error2 namespace.
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#define BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE_END }
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#endif
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//! Namespace for the library
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BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE_BEGIN
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//! Namespace for user specialised traits
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namespace traits
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{
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/*! Specialise to true if you guarantee that a type is move bitcopying (i.e.
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its move constructor equals copying bits from old to new, old is left in a
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default constructed state, and calling the destructor on a default constructed
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instance is trivial). All trivially copyable types are move bitcopying by
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definition, and that is the unspecialised implementation.
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*/
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template <class T> struct is_move_bitcopying
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{
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static constexpr bool value = std::is_trivially_copyable<T>::value;
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};
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} // namespace traits
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namespace detail
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{
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#if __cplusplus >= 201400 || _MSC_VER >= 1910 /* VS2017 */
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inline constexpr size_t cstrlen(const char *str)
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{
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const char *end = nullptr;
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for(end = str; *end != 0; ++end) // NOLINT
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;
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return end - str;
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}
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#else
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inline constexpr size_t cstrlen_(const char *str, size_t acc) { return (str[0] == 0) ? acc : cstrlen_(str + 1, acc + 1); }
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inline constexpr size_t cstrlen(const char *str) { return cstrlen_(str, 0); }
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#endif
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/* A partially compliant implementation of C++20's std::bit_cast function contributed
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by Jesse Towner.
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Our bit_cast is only guaranteed to be constexpr when both the input and output
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arguments are either integrals or enums. However, this covers most use cases
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since the vast majority of status_codes have an underlying type that is either
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an integral or enum. We still attempt a constexpr union-based type pun for non-array
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input types, which some compilers accept. For array inputs, we fall back to
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non-constexpr memmove.
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*/
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template <class T> using is_integral_or_enum = std::integral_constant<bool, std::is_integral<T>::value || std::is_enum<T>::value>;
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template <class To, class From> using is_static_castable = std::integral_constant<bool, is_integral_or_enum<To>::value && is_integral_or_enum<From>::value>;
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template <class To, class From> using is_union_castable = std::integral_constant<bool, !is_static_castable<To, From>::value && !std::is_array<To>::value && !std::is_array<From>::value>;
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template <class To, class From> using is_bit_castable = std::integral_constant<bool, sizeof(To) == sizeof(From) && traits::is_move_bitcopying<To>::value && traits::is_move_bitcopying<From>::value>;
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template <class To, class From> union bit_cast_union
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{
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From source;
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To target;
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};
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#if BOOST_OUTCOME_SYSTEM_ERROR2_HAVE_BIT_CAST
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using std::bit_cast; // available for all trivially copyable types
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// For move bit copying types
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template <class To, class From>
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requires(is_bit_castable<To, From>::value //
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&&is_union_castable<To, From>::value //
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&& (!std::is_trivially_copyable_v<From> //
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|| !std::is_trivially_copyable_v<To>) ) //
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constexpr To bit_cast(const From &from) noexcept
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{
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return bit_cast_union<To, From>{from}.target;
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}
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template <class To, class From>
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requires(is_bit_castable<To, From>::value //
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&& !is_union_castable<To, From>::value //
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&& (!std::is_trivially_copyable_v<From> //
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|| !std::is_trivially_copyable_v<To>) ) //
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To bit_cast(const From &from) noexcept
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{
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bit_cast_union<To, From> ret;
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memmove(&ret.source, &from, sizeof(ret.source));
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return ret.target;
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}
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#else
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BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(class To, class From, int = 5)
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BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(is_bit_castable<To, From>::value //
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&&is_static_castable<To, From>::value //
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&& !is_union_castable<To, From>::value))
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constexpr To bit_cast(const From &from) noexcept { return static_cast<To>(from); }
|
||
|
|
|
||
|
|
#if defined(__GNUC__) && !defined(__clang__)
|
||
|
|
#pragma GCC diagnostic push
|
||
|
|
#pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
|
||
|
|
#endif
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(class To, class From, long = 5)
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(is_bit_castable<To, From>::value //
|
||
|
|
&& !is_static_castable<To, From>::value //
|
||
|
|
&& is_union_castable<To, From>::value))
|
||
|
|
constexpr To bit_cast(const From &from) noexcept { return bit_cast_union<To, From>{from}.target; }
|
||
|
|
#if defined(__GNUC__) && !defined(__clang__)
|
||
|
|
#pragma GCC diagnostic pop
|
||
|
|
#endif
|
||
|
|
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(class To, class From, short = 5)
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(is_bit_castable<To, From>::value //
|
||
|
|
&& !is_static_castable<To, From>::value //
|
||
|
|
&& !is_union_castable<To, From>::value))
|
||
|
|
To bit_cast(const From &from) noexcept
|
||
|
|
{
|
||
|
|
bit_cast_union<To, From> ret;
|
||
|
|
memmove(&ret.source, &from, sizeof(ret.source));
|
||
|
|
return ret.target;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* erasure_cast performs a bit_cast with additional rules to handle types
|
||
|
|
of differing sizes. For integral & enum types, it may perform a narrowing
|
||
|
|
or widing conversion with static_cast if necessary, before doing the final
|
||
|
|
conversion with bit_cast. When casting to or from non-integral, non-enum
|
||
|
|
types it may insert the value into another object with extra padding bytes
|
||
|
|
to satisfy bit_cast's preconditions that both types have the same size. */
|
||
|
|
|
||
|
|
template <class To, class From> using is_erasure_castable = std::integral_constant<bool, traits::is_move_bitcopying<To>::value && traits::is_move_bitcopying<From>::value>;
|
||
|
|
|
||
|
|
template <class T, bool = std::is_enum<T>::value> struct identity_or_underlying_type
|
||
|
|
{
|
||
|
|
using type = T;
|
||
|
|
};
|
||
|
|
template <class T> struct identity_or_underlying_type<T, true>
|
||
|
|
{
|
||
|
|
using type = typename std::underlying_type<T>::type;
|
||
|
|
};
|
||
|
|
|
||
|
|
template <class OfSize, class OfSign>
|
||
|
|
using erasure_integer_type = typename std::conditional<std::is_signed<typename identity_or_underlying_type<OfSign>::type>::value, typename std::make_signed<typename identity_or_underlying_type<OfSize>::type>::type, typename std::make_unsigned<typename identity_or_underlying_type<OfSize>::type>::type>::type;
|
||
|
|
|
||
|
|
template <class ErasedType, std::size_t N> struct padded_erasure_object
|
||
|
|
{
|
||
|
|
static_assert(traits::is_move_bitcopying<ErasedType>::value, "ErasedType must be TriviallyCopyable or MoveBitcopying");
|
||
|
|
static_assert(alignof(ErasedType) <= sizeof(ErasedType), "ErasedType must not be over-aligned");
|
||
|
|
ErasedType value;
|
||
|
|
char padding[N];
|
||
|
|
constexpr explicit padded_erasure_object(const ErasedType &v) noexcept
|
||
|
|
: value(v)
|
||
|
|
, padding{}
|
||
|
|
{
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(class To, class From)
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(is_erasure_castable<To, From>::value && (sizeof(To) == sizeof(From)))) constexpr To erasure_cast(const From &from) noexcept { return bit_cast<To>(from); }
|
||
|
|
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(class To, class From, long = 5)
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(is_erasure_castable<To, From>::value &&is_static_castable<To, From>::value && (sizeof(To) < sizeof(From)))) constexpr To erasure_cast(const From &from) noexcept { return static_cast<To>(bit_cast<erasure_integer_type<From, To>>(from)); }
|
||
|
|
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(class To, class From, int = 5)
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(is_erasure_castable<To, From>::value &&is_static_castable<To, From>::value && (sizeof(To) > sizeof(From)))) constexpr To erasure_cast(const From &from) noexcept { return bit_cast<To>(static_cast<erasure_integer_type<To, From>>(from)); }
|
||
|
|
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(class To, class From, short = 5)
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(is_erasure_castable<To, From>::value && !is_static_castable<To, From>::value && (sizeof(To) < sizeof(From)))) constexpr To erasure_cast(const From &from) noexcept { return bit_cast<padded_erasure_object<To, sizeof(From) - sizeof(To)>>(from).value; }
|
||
|
|
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(class To, class From, char = 5)
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(is_erasure_castable<To, From>::value && !is_static_castable<To, From>::value && (sizeof(To) > sizeof(From)))) constexpr To erasure_cast(const From &from) noexcept { return bit_cast<To>(padded_erasure_object<From, sizeof(To) - sizeof(From)>{from}); }
|
||
|
|
} // namespace detail
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE_END
|
||
|
|
|
||
|
|
#ifndef BOOST_OUTCOME_SYSTEM_ERROR2_FATAL
|
||
|
|
#ifdef BOOST_OUTCOME_SYSTEM_ERROR2_NOT_POSIX
|
||
|
|
#error If BOOST_OUTCOME_SYSTEM_ERROR2_NOT_POSIX is defined, you must define your own BOOST_OUTCOME_SYSTEM_ERROR2_FATAL implementation!
|
||
|
|
#endif
|
||
|
|
#include <cstdlib> // for abort
|
||
|
|
#ifdef __APPLE__
|
||
|
|
#include <unistd.h> // for write
|
||
|
|
#endif
|
||
|
|
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE_BEGIN
|
||
|
|
namespace detail
|
||
|
|
{
|
||
|
|
namespace avoid_stdio_include
|
||
|
|
{
|
||
|
|
#if !defined(__APPLE__) && !defined(_MSC_VER)
|
||
|
|
extern "C" ptrdiff_t write(int, const void *, size_t);
|
||
|
|
#elif defined(_MSC_VER)
|
||
|
|
extern ptrdiff_t write(int, const void *, size_t);
|
||
|
|
#if(defined(__x86_64__) || defined(_M_X64)) || (defined(__aarch64__) || defined(_M_ARM64)) || (defined(__arm__) || defined(_M_ARM))
|
||
|
|
#pragma comment(linker, "/alternatename:?write@avoid_stdio_include@detail@system_error2@@YA_JHPEBX_K@Z=write")
|
||
|
|
#elif defined(__x86__) || defined(_M_IX86) || defined(__i386__)
|
||
|
|
#pragma comment(linker, "/alternatename:?write@avoid_stdio_include@detail@system_error2@@YAHHPBXI@Z=_write")
|
||
|
|
#else
|
||
|
|
#error Unknown architecture
|
||
|
|
#endif
|
||
|
|
#endif
|
||
|
|
} // namespace avoid_stdio_include
|
||
|
|
inline void do_fatal_exit(const char *msg)
|
||
|
|
{
|
||
|
|
using namespace avoid_stdio_include;
|
||
|
|
write(2 /*stderr*/, msg, cstrlen(msg));
|
||
|
|
write(2 /*stderr*/, "\n", 1);
|
||
|
|
abort();
|
||
|
|
}
|
||
|
|
} // namespace detail
|
||
|
|
BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE_END
|
||
|
|
//! Prints msg to stderr, and calls `std::terminate()`. Can be overriden via predefinition.
|
||
|
|
#define BOOST_OUTCOME_SYSTEM_ERROR2_FATAL(msg) ::BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::detail::do_fatal_exit(msg)
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#endif
|