text: //
  // detail/impl/reactive_descriptor_service.ipp
  // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2021 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_IMPL_REACTIVE_DESCRIPTOR_SERVICE_IPP
  #define BOOST_ASIO_DETAIL_IMPL_REACTIVE_DESCRIPTOR_SERVICE_IPP
  
  #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_WINDOWS) \
    && !defined(BOOST_ASIO_WINDOWS_RUNTIME) \
    && !defined(__CYGWIN__)
  
  #include <boost/asio/error.hpp>
  #include <boost/asio/detail/reactive_descriptor_service.hpp>
  
  #include <boost/asio/detail/push_options.hpp>
  
  namespace boost {
  namespace asio {
  namespace detail {
  
  reactive_descriptor_service::reactive_descriptor_service(
      execution_context& context)
    : execution_context_service_base<reactive_descriptor_service>(context),
      reactor_(boost::asio::use_service<reactor>(context))
  {
    reactor_.init_task();
  }
  
  void reactive_descriptor_service::shutdown()
  {
  }
  
  void reactive_descriptor_service::construct(
      reactive_descriptor_service::implementation_type& impl)
  {
    impl.descriptor_ = -1;
    impl.state_ = 0;
  }
  
  void reactive_descriptor_service::move_construct(
      reactive_descriptor_service::implementation_type& impl,
      reactive_descriptor_service::implementation_type& other_impl)
    BOOST_ASIO_NOEXCEPT
  {
    impl.descriptor_ = other_impl.descriptor_;
    other_impl.descriptor_ = -1;
  
    impl.state_ = other_impl.state_;
    other_impl.state_ = 0;
  
    reactor_.move_descriptor(impl.descriptor_,
        impl.reactor_data_, other_impl.reactor_data_);
  }
  
  void reactive_descriptor_service::move_assign(
      reactive_descriptor_service::implementation_type& impl,
      reactive_descriptor_service& other_service,
      reactive_descriptor_service::implementation_type& other_impl)
  {
    destroy(impl);
  
    impl.descriptor_ = other_impl.descriptor_;
    other_impl.descriptor_ = -1;
  
    impl.state_ = other_impl.state_;
    other_impl.state_ = 0;
  
    other_service.reactor_.move_descriptor(impl.descriptor_,
        impl.reactor_data_, other_impl.reactor_data_);
  }
  
  void reactive_descriptor_service::destroy(
      reactive_descriptor_service::implementation_type& impl)
  {
    if (is_open(impl))
    {
      BOOST_ASIO_HANDLER_OPERATION((reactor_.context(),
            "descriptor", &impl, impl.descriptor_, "close"));
  
      reactor_.deregister_descriptor(impl.descriptor_, impl.reactor_data_,
          (impl.state_ & descriptor_ops::possible_dup) == 0);
  
      boost::system::error_code ignored_ec;
      descriptor_ops::close(impl.descriptor_, impl.state_, ignored_ec);
  
      reactor_.cleanup_descriptor_data(impl.reactor_data_);
    }
  }
  
  boost::system::error_code reactive_descriptor_service::assign(
      reactive_descriptor_service::implementation_type& impl,
      const native_handle_type& native_descriptor, boost::system::error_code& ec)
  {
    if (is_open(impl))
    {
      ec = boost::asio::error::already_open;
      return ec;
    }
  
    if (int err = reactor_.register_descriptor(
          native_descriptor, impl.reactor_data_))
    {
      ec = boost::system::error_code(err,
          boost::asio::error::get_system_category());
      return ec;
    }
  
    impl.descriptor_ = native_descriptor;
    impl.state_ = descriptor_ops::possible_dup;
    ec = boost::system::error_code();
    return ec;
  }
  
  boost::system::error_code reactive_descriptor_service::close(
      reactive_descriptor_service::implementation_type& impl,
      boost::system::error_code& ec)
  {
    if (is_open(impl))
    {
      BOOST_ASIO_HANDLER_OPERATION((reactor_.context(),
            "descriptor", &impl, impl.descriptor_, "close"));
  
      reactor_.deregister_descriptor(impl.descriptor_, impl.reactor_data_,
          (impl.state_ & descriptor_ops::possible_dup) == 0);
  
      descriptor_ops::close(impl.descriptor_, impl.state_, ec);
  
      reactor_.cleanup_descriptor_data(impl.reactor_data_);
    }
    else
    {
      ec = boost::system::error_code();
    }
  
    // The descriptor is closed by the OS even if close() returns an error.
    //
    // (Actually, POSIX says the state of the descriptor is unspecified. On
    // Linux the descriptor is apparently closed anyway; e.g. see
    //   http://lkml.org/lkml/2005/9/10/129
    // We'll just have to assume that other OSes follow the same behaviour.)
    construct(impl);
  
    return ec;
  }
  
  reactive_descriptor_service::native_handle_type
  reactive_descriptor_service::release(
      reactive_descriptor_service::implementation_type& impl)
  {
    native_handle_type descriptor = impl.descriptor_;
  
    if (is_open(impl))
    {
      BOOST_ASIO_HANDLER_OPERATION((reactor_.context(),
            "descriptor", &impl, impl.descriptor_, "release"));
  
      reactor_.deregister_descriptor(impl.descriptor_, impl.reactor_data_, false);
      reactor_.cleanup_descriptor_data(impl.reactor_data_);
      construct(impl);
    }
  
    return descriptor;
  }
  
  boost::system::error_code reactive_descriptor_service::cancel(
      reactive_descriptor_service::implementation_type& impl,
      boost::system::error_code& ec)
  {
    if (!is_open(impl))
    {
      ec = boost::asio::error::bad_descriptor;
      return ec;
    }
  
    BOOST_ASIO_HANDLER_OPERATION((reactor_.context(),
          "descriptor", &impl, impl.descriptor_, "cancel"));
  
    reactor_.cancel_ops(impl.descriptor_, impl.reactor_data_);
    ec = boost::system::error_code();
    return ec;
  }
  
  void reactive_descriptor_service::start_op(
      reactive_descriptor_service::implementation_type& impl,
      int op_type, reactor_op* op, bool is_continuation,
      bool is_non_blocking, bool noop)
  {
    if (!noop)
    {
      if ((impl.state_ & descriptor_ops::non_blocking) ||
          descriptor_ops::set_internal_non_blocking(
            impl.descriptor_, impl.state_, true, op->ec_))
      {
        reactor_.start_op(op_type, impl.descriptor_,
            impl.reactor_data_, op, is_continuation, is_non_blocking);
        return;
      }
    }
  
    reactor_.post_immediate_completion(op, is_continuation);
  }
  
  } // namespace detail
  } // namespace asio
  } // namespace boost
  
  #include <boost/asio/detail/pop_options.hpp>
  
  #endif // !defined(BOOST_ASIO_WINDOWS)
         //   && !defined(BOOST_ASIO_WINDOWS_RUNTIME)
         //   && !defined(__CYGWIN__)
  
  #endif // BOOST_ASIO_DETAIL_IMPL_REACTIVE_DESCRIPTOR_SERVICE_IPP
  