ceph/src/boost/boost/asio/experimental/co_spawn.hpp

   1 //
   2 // experimental/co_spawn.hpp
   3 // ~~~~~~~~~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2021-2022 Klemens D. Morgenstern
   6 //                         (klemens dot morgenstern at gmx dot net)
   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 #ifndef BOOST_ASIO_EXPERIMENTAL_CO_SPAWN_HPP
  12 #define BOOST_ASIO_EXPERIMENTAL_CO_SPAWN_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 <utility>
  20 #include <boost/asio/compose.hpp>
  21 #include <boost/asio/detail/type_traits.hpp>
  22 #include <boost/asio/experimental/coro.hpp>
  23 #include <boost/asio/experimental/deferred.hpp>
  24 #include <boost/asio/experimental/prepend.hpp>
  25 #include <boost/asio/redirect_error.hpp>
  26
  27 #include <boost/asio/detail/push_options.hpp>
  28
  29 namespace boost {
  30 namespace asio {
  31 namespace experimental {
  32 namespace detail {
  33
  34 template <typename T, typename U, typename Executor>
  35 struct coro_spawn_op
  36 {
  37   coro<T, U, Executor> c;
  38
  39   void operator()(auto& self)
  40   {
  41     auto op = c.async_resume(deferred);
  42     std::move(op)((prepend)(std::move(self), 0));
  43   }
  44
  45   void operator()(auto& self, int, auto... res)
  46   {
  47     self.complete(std::move(res)...);
  48   }
  49 };
  50
  51 } // namespace detail
  52
  53 /// Spawn a resumable coroutine.
  54 /**
  55  * This function spawns the coroutine for execution on its executor. It binds
  56  * the lifetime of the coroutine to the executor.
  57  *
  58  * @param c The coroutine
  59  *
  60  * @param token The completion token
  61  *
  62  * @returns Implementation defined
  63  */
  64 template <typename T, typename Executor, typename CompletionToken>
  65 BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(
  66     CompletionToken, void(std::exception_ptr, T))
  67 co_spawn(coro<void, T, Executor> c, CompletionToken&& token)
  68 {
  69   auto exec = c.get_executor();
  70   return async_compose<CompletionToken, void(std::exception_ptr, T)>(
  71       detail::coro_spawn_op<void, T, Executor>{std::move(c)},
  72       token, exec);
  73 }
  74
  75 /// Spawn a resumable coroutine.
  76 /**
  77  * This function spawns the coroutine for execution on its executor. It binds
  78  * the lifetime of the coroutine to the executor.
  79  *
  80  * @param c The coroutine
  81  *
  82  * @param token The completion token
  83  *
  84  * @returns Implementation defined
  85  */
  86 template <typename T, typename Executor, typename CompletionToken>
  87 BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(
  88     CompletionToken, void(std::exception_ptr, T))
  89 co_spawn(coro<void(), T, Executor> c, CompletionToken&& token)
  90 {
  91   auto exec = c.get_executor();
  92   return async_compose<CompletionToken, void(std::exception_ptr, T)>(
  93       detail::coro_spawn_op<void(), T, Executor>{std::move(c)},
  94       token, exec);
  95 }
  96
  97 /// Spawn a resumable coroutine.
  98 /**
  99  * This function spawns the coroutine for execution on its executor. It binds
 100  * the lifetime of the coroutine to the executor.
 101  *
 102  * @param c The coroutine
 103  *
 104  * @param token The completion token
 105  *
 106  * @returns Implementation defined
 107  */
 108 template <typename T, typename Executor, typename CompletionToken>
 109 BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void(T))
 110 co_spawn(coro<void() noexcept, T, Executor> c, CompletionToken&& token)
 111 {
 112   auto exec = c.get_executor();
 113   return async_compose<CompletionToken, void(T)>(
 114       detail::coro_spawn_op<void() noexcept, T, Executor>{std::move(c)},
 115       token, exec);
 116 }
 117
 118 /// Spawn a resumable coroutine.
 119 /**
 120  * This function spawns the coroutine for execution on its executor. It binds
 121  * the lifetime of the coroutine to the executor.
 122  *
 123  * @param c The coroutine
 124  *
 125  * @param token The completion token
 126  *
 127  * @returns Implementation defined
 128  */
 129 template <typename Executor, typename CompletionToken>
 130 BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(
 131     CompletionToken, void(std::exception_ptr))
 132 co_spawn(coro<void, void, Executor> c, CompletionToken&& token)
 133 {
 134   auto exec = c.get_executor();
 135   return async_compose<CompletionToken, void(std::exception_ptr)>(
 136       detail::coro_spawn_op<void, void, Executor>{std::move(c)},
 137       token, exec);
 138 }
 139
 140 /// Spawn a resumable coroutine.
 141 /**
 142  * This function spawns the coroutine for execution on its executor. It binds
 143  * the lifetime of the coroutine to the executor.
 144  *
 145  * @param c The coroutine
 146  *
 147  * @param token The completion token
 148  *
 149  * @returns Implementation defined
 150  */
 151 template <typename Executor, typename CompletionToken>
 152 BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(
 153     CompletionToken, void(std::exception_ptr))
 154 co_spawn(coro<void(), void, Executor> c, CompletionToken&& token)
 155 {
 156   auto exec = c.get_executor();
 157   return async_compose<CompletionToken, void(std::exception_ptr)>(
 158       detail::coro_spawn_op<void(), void, Executor>{std::move(c)},
 159       token, exec);
 160 }
 161
 162 /// Spawn a resumable coroutine.
 163 /**
 164  * This function spawns the coroutine for execution on its executor. It binds
 165  * the lifetime of the coroutine to the executor.
 166  *
 167  * @param c The coroutine
 168  *
 169  * @param token The completion token
 170  *
 171  * @returns Implementation defined
 172  */
 173 template <typename Executor, typename CompletionToken>
 174 BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void())
 175 co_spawn(coro<void() noexcept, void, Executor> c, CompletionToken&& token)
 176 {
 177   auto exec = c.get_executor();
 178   return async_compose<CompletionToken, void()>(
 179       detail::coro_spawn_op<void() noexcept, void, Executor>{std::move(c)},
 180       token, exec);
 181 }
 182
 183 } // namespace detail
 184 } // namespace asio
 185 } // namespace boost
 186
 187 #include <boost/asio/detail/pop_options.hpp>
 188
 189 #endif //BOOST_ASIO_EXPERIMENTAL_CO_SPAWN_HPP