Insane_DNS/libraries/asio-1.28.1/include/asio/experimental/detail/channel_payload.hpp

140 lines
3.0 KiB
C++

//
// experimental/detail/channel_payload.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_EXPERIMENTAL_DETAIL_CHANNEL_PAYLOAD_HPP
#define ASIO_EXPERIMENTAL_DETAIL_CHANNEL_PAYLOAD_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/type_traits.hpp"
#include "asio/error_code.hpp"
#include "asio/experimental/detail/channel_message.hpp"
#if defined(ASIO_HAS_STD_VARIANT)
# include <variant>
#endif // defined(ASIO_HAS_STD_VARIANT)
#include "asio/detail/push_options.hpp"
namespace asio {
namespace experimental {
namespace detail {
template <typename... Signatures>
class channel_payload;
template <typename R>
class channel_payload<R()>
{
public:
explicit channel_payload(channel_message<R()>)
{
}
template <typename Handler>
void receive(Handler& handler)
{
ASIO_MOVE_OR_LVALUE(Handler)(handler)();
}
};
template <typename Signature>
class channel_payload<Signature>
{
public:
channel_payload(ASIO_MOVE_ARG(channel_message<Signature>) m)
: message_(ASIO_MOVE_CAST(channel_message<Signature>)(m))
{
}
template <typename Handler>
void receive(Handler& handler)
{
message_.receive(handler);
}
private:
channel_message<Signature> message_;
};
#if defined(ASIO_HAS_STD_VARIANT)
template <typename... Signatures>
class channel_payload
{
public:
template <typename Signature>
channel_payload(ASIO_MOVE_ARG(channel_message<Signature>) m)
: message_(ASIO_MOVE_CAST(channel_message<Signature>)(m))
{
}
template <typename Handler>
void receive(Handler& handler)
{
std::visit(
[&](auto& message)
{
message.receive(handler);
}, message_);
}
private:
std::variant<channel_message<Signatures>...> message_;
};
#else // defined(ASIO_HAS_STD_VARIANT)
template <typename R1, typename R2>
class channel_payload<R1(), R2(asio::error_code)>
{
public:
typedef channel_message<R1()> void_message_type;
typedef channel_message<R2(asio::error_code)> error_message_type;
channel_payload(ASIO_MOVE_ARG(void_message_type))
: message_(0, asio::error_code()),
empty_(true)
{
}
channel_payload(ASIO_MOVE_ARG(error_message_type) m)
: message_(ASIO_MOVE_CAST(error_message_type)(m)),
empty_(false)
{
}
template <typename Handler>
void receive(Handler& handler)
{
if (empty_)
channel_message<R1()>(0).receive(handler);
else
message_.receive(handler);
}
private:
error_message_type message_;
bool empty_;
};
#endif // defined(ASIO_HAS_STD_VARIANT)
} // namespace detail
} // namespace experimental
} // namespace asio
#include "asio/detail/pop_options.hpp"
#endif // ASIO_EXPERIMENTAL_DETAIL_CHANNEL_PAYLOAD_HPP