text: //
  // detail/impl/io_uring_descriptor_service.ipp
  // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2022 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_DETAIL_IMPL_IO_URING_DESCRIPTOR_SERVICE_IPP
  #define ASIO_DETAIL_IMPL_IO_URING_DESCRIPTOR_SERVICE_IPP
  
  #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  # pragma once
  #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  
  #include "asio/detail/config.hpp"
  
  #if defined(ASIO_HAS_IO_URING)
  
  #include "asio/error.hpp"
  #include "asio/detail/io_uring_descriptor_service.hpp"
  
  #include "asio/detail/push_options.hpp"
  
  namespace asio {
  namespace detail {
  
  io_uring_descriptor_service::io_uring_descriptor_service(
      execution_context& context)
    : execution_context_service_base<io_uring_descriptor_service>(context),
      io_uring_service_(asio::use_service<io_uring_service>(context))
  {
    io_uring_service_.init_task();
  }
  
  void io_uring_descriptor_service::shutdown()
  {
  }
  
  void io_uring_descriptor_service::construct(
      io_uring_descriptor_service::implementation_type& impl)
  {
    impl.descriptor_ = -1;
    impl.state_ = 0;
    impl.io_object_data_ = 0;
  }
  
  void io_uring_descriptor_service::move_construct(
      io_uring_descriptor_service::implementation_type& impl,
      io_uring_descriptor_service::implementation_type& other_impl)
    ASIO_NOEXCEPT
  {
    impl.descriptor_ = other_impl.descriptor_;
    other_impl.descriptor_ = -1;
  
    impl.state_ = other_impl.state_;
    other_impl.state_ = 0;
  
    impl.io_object_data_ = other_impl.io_object_data_;
    other_impl.io_object_data_ = 0;
  }
  
  void io_uring_descriptor_service::move_assign(
      io_uring_descriptor_service::implementation_type& impl,
      io_uring_descriptor_service& /*other_service*/,
      io_uring_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;
  
    impl.io_object_data_ = other_impl.io_object_data_;
    other_impl.io_object_data_ = 0;
  }
  
  void io_uring_descriptor_service::destroy(
      io_uring_descriptor_service::implementation_type& impl)
  {
    if (is_open(impl))
    {
      ASIO_HANDLER_OPERATION((io_uring_service_.context(),
            "descriptor", &impl, impl.descriptor_, "close"));
  
      io_uring_service_.deregister_io_object(impl.io_object_data_);
      asio::error_code ignored_ec;
      descriptor_ops::close(impl.descriptor_, impl.state_, ignored_ec);
      io_uring_service_.cleanup_io_object(impl.io_object_data_);
    }
  }
  
  asio::error_code io_uring_descriptor_service::assign(
      io_uring_descriptor_service::implementation_type& impl,
      const native_handle_type& native_descriptor, asio::error_code& ec)
  {
    if (is_open(impl))
    {
      ec = asio::error::already_open;
      return ec;
    }
  
    io_uring_service_.register_io_object(impl.io_object_data_);
  
    impl.descriptor_ = native_descriptor;
    impl.state_ = descriptor_ops::possible_dup;
    ec = success_ec_;
    return ec;
  }
  
  asio::error_code io_uring_descriptor_service::close(
      io_uring_descriptor_service::implementation_type& impl,
      asio::error_code& ec)
  {
    if (is_open(impl))
    {
      ASIO_HANDLER_OPERATION((io_uring_service_.context(),
            "descriptor", &impl, impl.descriptor_, "close"));
  
      io_uring_service_.deregister_io_object(impl.io_object_data_);
      descriptor_ops::close(impl.descriptor_, impl.state_, ec);
      io_uring_service_.cleanup_io_object(impl.io_object_data_);
    }
    else
    {
      ec = success_ec_;
    }
  
    // 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
    construct(impl);
  
    return ec;
  }
  
  io_uring_descriptor_service::native_handle_type
  io_uring_descriptor_service::release(
      io_uring_descriptor_service::implementation_type& impl)
  {
    native_handle_type descriptor = impl.descriptor_;
  
    if (is_open(impl))
    {
      ASIO_HANDLER_OPERATION((io_uring_service_.context(),
            "descriptor", &impl, impl.descriptor_, "release"));
  
      io_uring_service_.deregister_io_object(impl.io_object_data_);
      io_uring_service_.cleanup_io_object(impl.io_object_data_);
      construct(impl);
    }
  
    return descriptor;
  }
  
  asio::error_code io_uring_descriptor_service::cancel(
      io_uring_descriptor_service::implementation_type& impl,
      asio::error_code& ec)
  {
    if (!is_open(impl))
    {
      ec = asio::error::bad_descriptor;
      return ec;
    }
  
    ASIO_HANDLER_OPERATION((io_uring_service_.context(),
          "descriptor", &impl, impl.descriptor_, "cancel"));
  
    io_uring_service_.cancel_ops(impl.io_object_data_);
    ec = success_ec_;
    return ec;
  }
  
  void io_uring_descriptor_service::start_op(
      io_uring_descriptor_service::implementation_type& impl,
      int op_type, io_uring_operation* op, bool is_continuation, bool noop)
  {
    if (!noop)
    {
      io_uring_service_.start_op(op_type,
          impl.io_object_data_, op, is_continuation);
    }
    else
    {
      io_uring_service_.post_immediate_completion(op, is_continuation);
    }
  }
  
  } // namespace detail
  } // namespace asio
  
  #include "asio/detail/pop_options.hpp"
  
  #endif // defined(ASIO_HAS_IO_URING)
  
  #endif // ASIO_DETAIL_IMPL_IO_URING_DESCRIPTOR_SERVICE_IPP
  