ceph/src/boost/boost/asio/traits/start_free.hpp

   1 //
   2 // traits/start_free.hpp
   3 // ~~~~~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2022 Christopher M. Kohlhoff (chris at kohlhoff dot com)
   6 //
   7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9 //
  10
  11 #ifndef BOOST_ASIO_TRAITS_START_FREE_HPP
  12 #define BOOST_ASIO_TRAITS_START_FREE_HPP
  13
  14 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  15 # pragma once
  16 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  17
  18 #include <boost/asio/detail/config.hpp>
  19 #include <boost/asio/detail/type_traits.hpp>
  20
  21 #if defined(BOOST_ASIO_HAS_DECLTYPE) \
  22   && defined(BOOST_ASIO_HAS_NOEXCEPT) \
  23   && defined(BOOST_ASIO_HAS_WORKING_EXPRESSION_SFINAE)
  24 # define BOOST_ASIO_HAS_DEDUCED_START_FREE_TRAIT 1
  25 #endif // defined(BOOST_ASIO_HAS_DECLTYPE)
  26        //   && defined(BOOST_ASIO_HAS_NOEXCEPT)
  27        //   && defined(BOOST_ASIO_HAS_WORKING_EXPRESSION_SFINAE)
  28
  29 #include <boost/asio/detail/push_options.hpp>
  30
  31 namespace boost {
  32 namespace asio {
  33 namespace traits {
  34
  35 template <typename T, typename = void>
  36 struct start_free_default;
  37
  38 template <typename T, typename = void>
  39 struct start_free;
  40
  41 } // namespace traits
  42 namespace detail {
  43
  44 struct no_start_free
  45 {
  46   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
  47   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
  48 };
  49
  50 #if defined(BOOST_ASIO_HAS_DEDUCED_START_FREE_TRAIT)
  51
  52 template <typename T, typename = void>
  53 struct start_free_trait : no_start_free
  54 {
  55 };
  56
  57 template <typename T>
  58 struct start_free_trait<T,
  59   typename void_type<
  60     decltype(start(declval<T>()))
  61   >::type>
  62 {
  63   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  64
  65   using result_type = decltype(start(declval<T>()));
  66
  67   BOOST_ASIO_STATIC_CONSTEXPR(bool,
  68     is_noexcept = noexcept(start(declval<T>())));
  69 };
  70
  71 #else // defined(BOOST_ASIO_HAS_DEDUCED_START_FREE_TRAIT)
  72
  73 template <typename T, typename = void>
  74 struct start_free_trait :
  75   conditional<
  76     is_same<T, typename remove_reference<T>::type>::value,
  77     typename conditional<
  78       is_same<T, typename add_const<T>::type>::value,
  79       no_start_free,
  80       traits::start_free<typename add_const<T>::type>
  81     >::type,
  82     traits::start_free<typename remove_reference<T>::type>
  83   >::type
  84 {
  85 };
  86
  87 #endif // defined(BOOST_ASIO_HAS_DEDUCED_START_FREE_TRAIT)
  88
  89 } // namespace detail
  90 namespace traits {
  91
  92 template <typename T, typename>
  93 struct start_free_default :
  94   detail::start_free_trait<T>
  95 {
  96 };
  97
  98 template <typename T, typename>
  99 struct start_free :
 100   start_free_default<T>
 101 {
 102 };
 103
 104 } // namespace traits
 105 } // namespace asio
 106 } // namespace boost
 107
 108 #include <boost/asio/detail/pop_options.hpp>
 109
 110 #endif // BOOST_ASIO_TRAITS_START_FREE_HPP