ext-boost/boost/asio/dispatch.hpp

111 lines
3.9 KiB
C++

//
// dispatch.hpp
// ~~~~~~~~~~~~
//
// Copyright (c) 2003-2019 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_DISPATCH_HPP
#define BOOST_ASIO_DISPATCH_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include <boost/asio/detail/config.hpp>
#include <boost/asio/async_result.hpp>
#include <boost/asio/detail/type_traits.hpp>
#include <boost/asio/execution_context.hpp>
#include <boost/asio/is_executor.hpp>
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
/// Submits a completion token or function object for execution.
/**
* This function submits an object for execution using the object's associated
* executor. The function object may be called from the current thread prior to
* returning from <tt>dispatch()</tt>. Otherwise, it is queued for execution.
*
* This function has the following effects:
*
* @li Constructs a function object handler of type @c Handler, initialized
* with <tt>handler(forward<CompletionToken>(token))</tt>.
*
* @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
* initializing the object as <tt>result(handler)</tt>.
*
* @li Obtains the handler's associated executor object @c ex by performing
* <tt>get_associated_executor(handler)</tt>.
*
* @li Obtains the handler's associated allocator object @c alloc by performing
* <tt>get_associated_allocator(handler)</tt>.
*
* @li Performs <tt>ex.dispatch(std::move(handler), alloc)</tt>.
*
* @li Returns <tt>result.get()</tt>.
*/
template <typename CompletionToken>
BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, void()) dispatch(
BOOST_ASIO_MOVE_ARG(CompletionToken) token);
/// Submits a completion token or function object for execution.
/**
* This function submits an object for execution using the specified executor.
* The function object may be called from the current thread prior to returning
* from <tt>dispatch()</tt>. Otherwise, it is queued for execution.
*
* This function has the following effects:
*
* @li Constructs a function object handler of type @c Handler, initialized
* with <tt>handler(forward<CompletionToken>(token))</tt>.
*
* @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
* initializing the object as <tt>result(handler)</tt>.
*
* @li Obtains the handler's associated executor object @c ex1 by performing
* <tt>get_associated_executor(handler)</tt>.
*
* @li Creates a work object @c w by performing <tt>make_work(ex1)</tt>.
*
* @li Obtains the handler's associated allocator object @c alloc by performing
* <tt>get_associated_allocator(handler)</tt>.
*
* @li Constructs a function object @c f with a function call operator that
* performs <tt>ex1.dispatch(std::move(handler), alloc)</tt> followed by
* <tt>w.reset()</tt>.
*
* @li Performs <tt>Executor(ex).dispatch(std::move(f), alloc)</tt>.
*
* @li Returns <tt>result.get()</tt>.
*/
template <typename Executor, typename CompletionToken>
BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, void()) dispatch(
const Executor& ex, BOOST_ASIO_MOVE_ARG(CompletionToken) token,
typename enable_if<is_executor<Executor>::value>::type* = 0);
/// Submits a completion token or function object for execution.
/**
* @returns <tt>dispatch(ctx.get_executor(),
* forward<CompletionToken>(token))</tt>.
*/
template <typename ExecutionContext, typename CompletionToken>
BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, void()) dispatch(
ExecutionContext& ctx, BOOST_ASIO_MOVE_ARG(CompletionToken) token,
typename enable_if<is_convertible<
ExecutionContext&, execution_context&>::value>::type* = 0);
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#include <boost/asio/impl/dispatch.hpp>
#endif // BOOST_ASIO_DISPATCH_HPP