boost/asio/detached.hpp
//
// detached.hpp
// ~~~~~~~~~~~~
//
// Copyright (c) 2003-2024 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 {
/// A @ref completion_token type 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.
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) 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,
constraint_t<
is_convertible<OtherExecutor, InnerExecutor>::value
> = 0) noexcept
: InnerExecutor(ex)
{
}
};
/// Type alias to adapt an I/O object to use @c detached_t as its
/// default completion token type.
template <typename T>
using as_default_on_t = typename T::template rebind_executor<
executor_with_default<typename T::executor_type>>::other;
/// 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<T>::template rebind_executor<
executor_with_default<typename decay_t<T>::executor_type>
>::other
as_default_on(T&& object)
{
return typename decay_t<T>::template rebind_executor<
executor_with_default<typename decay_t<T>::executor_type>
>::other(static_cast<T&&>(object));
}
};
/// A @ref completion_token object used to specify that an asynchronous
/// operation is detached.
/**
* See the documentation for boost::asio::detached_t for a usage example.
*/
BOOST_ASIO_INLINE_VARIABLE constexpr detached_t detached;
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#include <boost/asio/impl/detached.hpp>
#endif // BOOST_ASIO_DETACHED_HPP