ext-boost/boost/asio/detail/executor_op.hpp
2019-08-24 15:39:04 +02:00

87 lines
2.5 KiB
C++

//
// detail/executor_op.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_DETAIL_EXECUTOR_OP_HPP
#define BOOST_ASIO_DETAIL_EXECUTOR_OP_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/detail/fenced_block.hpp>
#include <boost/asio/detail/handler_alloc_helpers.hpp>
#include <boost/asio/detail/handler_invoke_helpers.hpp>
#include <boost/asio/detail/scheduler_operation.hpp>
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
namespace detail {
template <typename Handler, typename Alloc,
typename Operation = scheduler_operation>
class executor_op : public Operation
{
public:
BOOST_ASIO_DEFINE_HANDLER_ALLOCATOR_PTR(executor_op);
template <typename H>
executor_op(BOOST_ASIO_MOVE_ARG(H) h, const Alloc& allocator)
: Operation(&executor_op::do_complete),
handler_(BOOST_ASIO_MOVE_CAST(H)(h)),
allocator_(allocator)
{
}
static void do_complete(void* owner, Operation* base,
const boost::system::error_code& /*ec*/,
std::size_t /*bytes_transferred*/)
{
// Take ownership of the handler object.
executor_op* o(static_cast<executor_op*>(base));
Alloc allocator(o->allocator_);
ptr p = { detail::addressof(allocator), o, o };
BOOST_ASIO_HANDLER_COMPLETION((*o));
// Make a copy of the handler so that the memory can be deallocated before
// the upcall is made. Even if we're not about to make an upcall, a
// sub-object of the handler may be the true owner of the memory associated
// with the handler. Consequently, a local copy of the handler is required
// to ensure that any owning sub-object remains valid until after we have
// deallocated the memory here.
Handler handler(BOOST_ASIO_MOVE_CAST(Handler)(o->handler_));
p.reset();
// Make the upcall if required.
if (owner)
{
fenced_block b(fenced_block::half);
BOOST_ASIO_HANDLER_INVOCATION_BEGIN(());
boost_asio_handler_invoke_helpers::invoke(handler, handler);
BOOST_ASIO_HANDLER_INVOCATION_END;
}
}
private:
Handler handler_;
Alloc allocator_;
};
} // namespace detail
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#endif // BOOST_ASIO_DETAIL_EXECUTOR_OP_HPP