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

86 lines
2.5 KiB
C++

//
// detail/eventfd_select_interrupter.hpp
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
// Copyright (c) 2008 Roelof Naude (roelof.naude at gmail 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_EVENTFD_SELECT_INTERRUPTER_HPP
#define BOOST_ASIO_DETAIL_EVENTFD_SELECT_INTERRUPTER_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include <boost/asio/detail/config.hpp>
#if defined(BOOST_ASIO_HAS_EVENTFD)
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
namespace detail {
class eventfd_select_interrupter
{
public:
// Constructor.
BOOST_ASIO_DECL eventfd_select_interrupter();
// Destructor.
BOOST_ASIO_DECL ~eventfd_select_interrupter();
// Recreate the interrupter's descriptors. Used after a fork.
BOOST_ASIO_DECL void recreate();
// Interrupt the select call.
BOOST_ASIO_DECL void interrupt();
// Reset the select interrupt. Returns true if the call was interrupted.
BOOST_ASIO_DECL bool reset();
// Get the read descriptor to be passed to select.
int read_descriptor() const
{
return read_descriptor_;
}
private:
// Open the descriptors. Throws on error.
BOOST_ASIO_DECL void open_descriptors();
// Close the descriptors.
BOOST_ASIO_DECL void close_descriptors();
// The read end of a connection used to interrupt the select call. This file
// descriptor is passed to select such that when it is time to stop, a single
// 64bit value will be written on the other end of the connection and this
// descriptor will become readable.
int read_descriptor_;
// The write end of a connection used to interrupt the select call. A single
// 64bit non-zero value may be written to this to wake up the select which is
// waiting for the other end to become readable. This descriptor will only
// differ from the read descriptor when a pipe is used.
int write_descriptor_;
};
} // namespace detail
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#if defined(BOOST_ASIO_HEADER_ONLY)
# include <boost/asio/detail/impl/eventfd_select_interrupter.ipp>
#endif // defined(BOOST_ASIO_HEADER_ONLY)
#endif // defined(BOOST_ASIO_HAS_EVENTFD)
#endif // BOOST_ASIO_DETAIL_EVENTFD_SELECT_INTERRUPTER_HPP