| // |
| // detached.hpp |
| // ~~~~~~~~~~~~ |
| // |
| // Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com) |
| // |
| // Distributed under the Boost Software License, Version 1.0. (See accompanying |
| // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| // |
| |
| #ifndef BOOST_ASIO_DETACHED_HPP |
| #define BOOST_ASIO_DETACHED_HPP |
| |
| #if defined(_MSC_VER) && (_MSC_VER >= 1200) |
| # pragma once |
| #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) |
| |
| #include <boost/asio/detail/config.hpp> |
| #include <memory> |
| #include <boost/asio/detail/type_traits.hpp> |
| |
| #include <boost/asio/detail/push_options.hpp> |
| |
| namespace boost { |
| namespace asio { |
| |
| /// Class used to specify that an asynchronous operation is detached. |
| /** |
| |
| * The detached_t class is used to indicate that an asynchronous operation is |
| * detached. That is, there is no completion handler waiting for the |
| * operation's result. A detached_t object may be passed as a handler to an |
| * asynchronous operation, typically using the special value |
| * @c boost::asio::detached. For example: |
| |
| * @code my_socket.async_send(my_buffer, boost::asio::detached); |
| * @endcode |
| */ |
| class detached_t |
| { |
| public: |
| /// Constructor. |
| BOOST_ASIO_CONSTEXPR detached_t() |
| { |
| } |
| |
| /// Adapts an executor to add the @c detached_t completion token as the |
| /// default. |
| template <typename InnerExecutor> |
| struct executor_with_default : InnerExecutor |
| { |
| /// Specify @c detached_t as the default completion token type. |
| typedef detached_t default_completion_token_type; |
| |
| /// Construct the adapted executor from the inner executor type. |
| executor_with_default(const InnerExecutor& ex) BOOST_ASIO_NOEXCEPT |
| : InnerExecutor(ex) |
| { |
| } |
| |
| /// Convert the specified executor to the inner executor type, then use |
| /// that to construct the adapted executor. |
| template <typename OtherExecutor> |
| executor_with_default(const OtherExecutor& ex, |
| typename constraint< |
| is_convertible<OtherExecutor, InnerExecutor>::value |
| >::type = 0) BOOST_ASIO_NOEXCEPT |
| : InnerExecutor(ex) |
| { |
| } |
| }; |
| |
| /// Type alias to adapt an I/O object to use @c detached_t as its |
| /// default completion token type. |
| #if defined(BOOST_ASIO_HAS_ALIAS_TEMPLATES) \ |
| || defined(GENERATING_DOCUMENTATION) |
| template <typename T> |
| using as_default_on_t = typename T::template rebind_executor< |
| executor_with_default<typename T::executor_type> >::other; |
| #endif // defined(BOOST_ASIO_HAS_ALIAS_TEMPLATES) |
| // || defined(GENERATING_DOCUMENTATION) |
| |
| /// Function helper to adapt an I/O object to use @c detached_t as its |
| /// default completion token type. |
| template <typename T> |
| static typename decay<T>::type::template rebind_executor< |
| executor_with_default<typename decay<T>::type::executor_type> |
| >::other |
| as_default_on(BOOST_ASIO_MOVE_ARG(T) object) |
| { |
| return typename decay<T>::type::template rebind_executor< |
| executor_with_default<typename decay<T>::type::executor_type> |
| >::other(BOOST_ASIO_MOVE_CAST(T)(object)); |
| } |
| }; |
| |
| /// A special value, similar to std::nothrow. |
| /** |
| * See the documentation for boost::asio::detached_t for a usage example. |
| */ |
| #if defined(BOOST_ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION) |
| constexpr detached_t detached; |
| #elif defined(BOOST_ASIO_MSVC) |
| __declspec(selectany) detached_t detached; |
| #endif |
| |
| } // namespace asio |
| } // namespace boost |
| |
| #include <boost/asio/detail/pop_options.hpp> |
| |
| #include <boost/asio/impl/detached.hpp> |
| |
| #endif // BOOST_ASIO_DETACHED_HPP |