detached.hpp 3.03 KB
//
// impl/detached.hpp
// ~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2020 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 ASIO_IMPL_DETACHED_HPP
#define ASIO_IMPL_DETACHED_HPP

#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)

#include "asio/detail/config.hpp"
#include "asio/async_result.hpp"
#include "asio/detail/variadic_templates.hpp"

#include "asio/detail/push_options.hpp"

namespace asio {
namespace detail {

  // Class to adapt a detached_t as a completion handler.
  class detached_handler
  {
  public:
    typedef void result_type;

    detached_handler(detached_t)
    {
    }

#if defined(ASIO_HAS_VARIADIC_TEMPLATES)

    template <typename... Args>
    void operator()(Args...)
    {
    }

#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)

    void operator()()
    {
    }

#define ASIO_PRIVATE_DETACHED_DEF(n) \
    template <ASIO_VARIADIC_TPARAMS(n)> \
    void operator()(ASIO_VARIADIC_TARGS(n)) \
    { \
    } \
    /**/
    ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_DETACHED_DEF)
#undef ASIO_PRIVATE_DETACHED_DEF

#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
  };

} // namespace detail

#if !defined(GENERATING_DOCUMENTATION)

template <typename Signature>
struct async_result<detached_t, Signature>
{
  typedef asio::detail::detached_handler completion_handler_type;

  typedef void return_type;

  explicit async_result(completion_handler_type&)
  {
  }

  void get()
  {
  }

#if defined(ASIO_HAS_VARIADIC_TEMPLATES)

  template <typename Initiation, typename RawCompletionToken, typename... Args>
  static return_type initiate(
      ASIO_MOVE_ARG(Initiation) initiation,
      ASIO_MOVE_ARG(RawCompletionToken),
      ASIO_MOVE_ARG(Args)... args)
  {
    ASIO_MOVE_CAST(Initiation)(initiation)(
        detail::detached_handler(detached_t()),
        ASIO_MOVE_CAST(Args)(args)...);
  }

#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)

  template <typename Initiation, typename RawCompletionToken>
  static return_type initiate(
      ASIO_MOVE_ARG(Initiation) initiation,
      ASIO_MOVE_ARG(RawCompletionToken))
  {
    ASIO_MOVE_CAST(Initiation)(initiation)(
        detail::detached_handler(detached_t()));
  }

#define ASIO_PRIVATE_INITIATE_DEF(n) \
  template <typename Initiation, typename RawCompletionToken, \
      ASIO_VARIADIC_TPARAMS(n)> \
  static return_type initiate( \
      ASIO_MOVE_ARG(Initiation) initiation, \
      ASIO_MOVE_ARG(RawCompletionToken), \
      ASIO_VARIADIC_MOVE_PARAMS(n)) \
  { \
    ASIO_MOVE_CAST(Initiation)(initiation)( \
        detail::detached_handler(detached_t()), \
        ASIO_VARIADIC_MOVE_ARGS(n)); \
  } \
  /**/
  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_INITIATE_DEF)
#undef ASIO_PRIVATE_INITIATE_DEF

#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
};

#endif // !defined(GENERATING_DOCUMENTATION)

} // namespace asio

#include "asio/detail/pop_options.hpp"

#endif // ASIO_IMPL_DETACHED_HPP