127 lines
3.1 KiB
C++
127 lines
3.1 KiB
C++
//
|
|
// packaged_task.hpp
|
|
// ~~~~~~~~~~~~~~~~~
|
|
//
|
|
// Copyright (c) 2003-2023 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_PACKAGED_TASK_HPP
|
|
#define ASIO_PACKAGED_TASK_HPP
|
|
|
|
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
|
|
# pragma once
|
|
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
|
|
|
|
#include "asio/detail/config.hpp"
|
|
#include "asio/detail/future.hpp"
|
|
|
|
#if defined(ASIO_HAS_STD_FUTURE_CLASS) \
|
|
|| defined(GENERATING_DOCUMENTATION)
|
|
|
|
#include "asio/async_result.hpp"
|
|
#include "asio/detail/type_traits.hpp"
|
|
#include "asio/detail/variadic_templates.hpp"
|
|
|
|
#include "asio/detail/push_options.hpp"
|
|
|
|
namespace asio {
|
|
|
|
#if defined(ASIO_HAS_VARIADIC_TEMPLATES) \
|
|
|| defined(GENERATING_DOCUMENTATION)
|
|
|
|
/// Partial specialisation of @c async_result for @c std::packaged_task.
|
|
template <typename Result, typename... Args, typename Signature>
|
|
class async_result<std::packaged_task<Result(Args...)>, Signature>
|
|
{
|
|
public:
|
|
/// The packaged task is the concrete completion handler type.
|
|
typedef std::packaged_task<Result(Args...)> completion_handler_type;
|
|
|
|
/// The return type of the initiating function is the future obtained from
|
|
/// the packaged task.
|
|
typedef std::future<Result> return_type;
|
|
|
|
/// The constructor extracts the future from the packaged task.
|
|
explicit async_result(completion_handler_type& h)
|
|
: future_(h.get_future())
|
|
{
|
|
}
|
|
|
|
/// Returns the packaged task's future.
|
|
return_type get()
|
|
{
|
|
return std::move(future_);
|
|
}
|
|
|
|
private:
|
|
return_type future_;
|
|
};
|
|
|
|
#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
|
|
// || defined(GENERATING_DOCUMENTATION)
|
|
|
|
template <typename Result, typename Signature>
|
|
struct async_result<std::packaged_task<Result()>, Signature>
|
|
{
|
|
typedef std::packaged_task<Result()> completion_handler_type;
|
|
typedef std::future<Result> return_type;
|
|
|
|
explicit async_result(completion_handler_type& h)
|
|
: future_(h.get_future())
|
|
{
|
|
}
|
|
|
|
return_type get()
|
|
{
|
|
return std::move(future_);
|
|
}
|
|
|
|
private:
|
|
return_type future_;
|
|
};
|
|
|
|
#define ASIO_PRIVATE_ASYNC_RESULT_DEF(n) \
|
|
template <typename Result, \
|
|
ASIO_VARIADIC_TPARAMS(n), typename Signature> \
|
|
class async_result< \
|
|
std::packaged_task<Result(ASIO_VARIADIC_TARGS(n))>, Signature> \
|
|
{ \
|
|
public: \
|
|
typedef std::packaged_task< \
|
|
Result(ASIO_VARIADIC_TARGS(n))> \
|
|
completion_handler_type; \
|
|
\
|
|
typedef std::future<Result> return_type; \
|
|
\
|
|
explicit async_result(completion_handler_type& h) \
|
|
: future_(h.get_future()) \
|
|
{ \
|
|
} \
|
|
\
|
|
return_type get() \
|
|
{ \
|
|
return std::move(future_); \
|
|
} \
|
|
\
|
|
private: \
|
|
return_type future_; \
|
|
}; \
|
|
/**/
|
|
ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_ASYNC_RESULT_DEF)
|
|
#undef ASIO_PRIVATE_ASYNC_RESULT_DEF
|
|
|
|
#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
|
|
// || defined(GENERATING_DOCUMENTATION)
|
|
|
|
} // namespace asio
|
|
|
|
#include "asio/detail/pop_options.hpp"
|
|
|
|
#endif // defined(ASIO_HAS_STD_FUTURE_CLASS)
|
|
// || defined(GENERATING_DOCUMENTATION)
|
|
|
|
#endif // ASIO_PACKAGED_TASK_HPP
|