ceph/src/boost/boost/asio/detail/is_executor.hpp

   1 //
   2 // detail/is_executor.hpp
   3 // ~~~~~~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2017 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_DETAIL_IS_EXECUTOR_HPP
  12 #define BOOST_ASIO_DETAIL_IS_EXECUTOR_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 #include <boost/asio/detail/push_options.hpp>
  22
  23 namespace boost {
  24 namespace asio {
  25 namespace detail {
  26
  27 struct executor_memfns_base
  28 {
  29   void context();
  30   void on_work_started();
  31   void on_work_finished();
  32   void dispatch();
  33   void post();
  34   void defer();
  35 };
  36
  37 template <typename T>
  38 struct executor_memfns_derived
  39   : T, executor_memfns_base
  40 {
  41 };
  42
  43 template <typename T, T>
  44 struct executor_memfns_check
  45 {
  46 };
  47
  48 template <typename>
  49 char (&context_memfn_helper(...))[2];
  50
  51 template <typename T>
  52 char context_memfn_helper(
  53     executor_memfns_check<
  54       void (executor_memfns_base::*)(),
  55       &executor_memfns_derived<T>::context>*);
  56
  57 template <typename>
  58 char (&on_work_started_memfn_helper(...))[2];
  59
  60 template <typename T>
  61 char on_work_started_memfn_helper(
  62     executor_memfns_check<
  63       void (executor_memfns_base::*)(),
  64       &executor_memfns_derived<T>::on_work_started>*);
  65
  66 template <typename>
  67 char (&on_work_finished_memfn_helper(...))[2];
  68
  69 template <typename T>
  70 char on_work_finished_memfn_helper(
  71     executor_memfns_check<
  72       void (executor_memfns_base::*)(),
  73       &executor_memfns_derived<T>::on_work_finished>*);
  74
  75 template <typename>
  76 char (&dispatch_memfn_helper(...))[2];
  77
  78 template <typename T>
  79 char dispatch_memfn_helper(
  80     executor_memfns_check<
  81       void (executor_memfns_base::*)(),
  82       &executor_memfns_derived<T>::dispatch>*);
  83
  84 template <typename>
  85 char (&post_memfn_helper(...))[2];
  86
  87 template <typename T>
  88 char post_memfn_helper(
  89     executor_memfns_check<
  90       void (executor_memfns_base::*)(),
  91       &executor_memfns_derived<T>::post>*);
  92
  93 template <typename>
  94 char (&defer_memfn_helper(...))[2];
  95
  96 template <typename T>
  97 char defer_memfn_helper(
  98     executor_memfns_check<
  99       void (executor_memfns_base::*)(),
 100       &executor_memfns_derived<T>::defer>*);
 101
 102 template <typename T>
 103 struct is_executor_class
 104   : integral_constant<bool,
 105       sizeof(context_memfn_helper<T>(0)) != 1 &&
 106       sizeof(on_work_started_memfn_helper<T>(0)) != 1 &&
 107       sizeof(on_work_finished_memfn_helper<T>(0)) != 1 &&
 108       sizeof(dispatch_memfn_helper<T>(0)) != 1 &&
 109       sizeof(post_memfn_helper<T>(0)) != 1 &&
 110       sizeof(defer_memfn_helper<T>(0)) != 1>
 111 {
 112 };
 113
 114 template <typename T>
 115 struct is_executor
 116   : conditional<is_class<T>::value,
 117       is_executor_class<T>,
 118       false_type>::type
 119 {
 120 };
 121
 122 } // namespace detail
 123 } // namespace asio
 124 } // namespace boost
 125
 126 #include <boost/asio/detail/pop_options.hpp>
 127
 128 #endif // BOOST_ASIO_DETAIL_IS_EXECUTOR_HPP