text: //
  // detail/win_iocp_serial_port_service.hpp
  // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2020 Christopher M. Kohlhoff (chris at kohlhoff dot com)
  // Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.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_WIN_IOCP_SERIAL_PORT_SERVICE_HPP
  #define ASIO_DETAIL_WIN_IOCP_SERIAL_PORT_SERVICE_HPP
  
  #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_IOCP) && defined(ASIO_HAS_SERIAL_PORT)
  
  #include <string>
  #include "asio/error.hpp"
  #include "asio/execution_context.hpp"
  #include "asio/detail/win_iocp_handle_service.hpp"
  
  #include "asio/detail/push_options.hpp"
  
  namespace asio {
  namespace detail {
  
  // Extend win_iocp_handle_service to provide serial port support.
  class win_iocp_serial_port_service :
    public execution_context_service_base<win_iocp_serial_port_service>
  {
  public:
    // The native type of a serial port.
    typedef win_iocp_handle_service::native_handle_type native_handle_type;
  
    // The implementation type of the serial port.
    typedef win_iocp_handle_service::implementation_type implementation_type;
  
    // Constructor.
    ASIO_DECL win_iocp_serial_port_service(execution_context& context);
  
    // Destroy all user-defined handler objects owned by the service.
    ASIO_DECL void shutdown();
  
    // Construct a new serial port implementation.
    void construct(implementation_type& impl)
    {
      handle_service_.construct(impl);
    }
  
    // Move-construct a new serial port implementation.
    void move_construct(implementation_type& impl,
        implementation_type& other_impl)
    {
      handle_service_.move_construct(impl, other_impl);
    }
  
    // Move-assign from another serial port implementation.
    void move_assign(implementation_type& impl,
        win_iocp_serial_port_service& other_service,
        implementation_type& other_impl)
    {
      handle_service_.move_assign(impl,
          other_service.handle_service_, other_impl);
    }
  
    // Destroy a serial port implementation.
    void destroy(implementation_type& impl)
    {
      handle_service_.destroy(impl);
    }
  
    // Open the serial port using the specified device name.
    ASIO_DECL asio::error_code open(implementation_type& impl,
        const std::string& device, asio::error_code& ec);
  
    // Assign a native handle to a serial port implementation.
    asio::error_code assign(implementation_type& impl,
        const native_handle_type& handle, asio::error_code& ec)
    {
      return handle_service_.assign(impl, handle, ec);
    }
  
    // Determine whether the serial port is open.
    bool is_open(const implementation_type& impl) const
    {
      return handle_service_.is_open(impl);
    }
  
    // Destroy a serial port implementation.
    asio::error_code close(implementation_type& impl,
        asio::error_code& ec)
    {
      return handle_service_.close(impl, ec);
    }
  
    // Get the native serial port representation.
    native_handle_type native_handle(implementation_type& impl)
    {
      return handle_service_.native_handle(impl);
    }
  
    // Cancel all operations associated with the handle.
    asio::error_code cancel(implementation_type& impl,
        asio::error_code& ec)
    {
      return handle_service_.cancel(impl, ec);
    }
  
    // Set an option on the serial port.
    template <typename SettableSerialPortOption>
    asio::error_code set_option(implementation_type& impl,
        const SettableSerialPortOption& option, asio::error_code& ec)
    {
      return do_set_option(impl,
          &win_iocp_serial_port_service::store_option<SettableSerialPortOption>,
          &option, ec);
    }
  
    // Get an option from the serial port.
    template <typename GettableSerialPortOption>
    asio::error_code get_option(const implementation_type& impl,
        GettableSerialPortOption& option, asio::error_code& ec) const
    {
      return do_get_option(impl,
          &win_iocp_serial_port_service::load_option<GettableSerialPortOption>,
          &option, ec);
    }
  
    // Send a break sequence to the serial port.
    asio::error_code send_break(implementation_type&,
        asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Write the given data. Returns the number of bytes sent.
    template <typename ConstBufferSequence>
    size_t write_some(implementation_type& impl,
        const ConstBufferSequence& buffers, asio::error_code& ec)
    {
      return handle_service_.write_some(impl, buffers, ec);
    }
  
    // Start an asynchronous write. The data being written must be valid for the
    // lifetime of the asynchronous operation.
    template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
    void async_write_some(implementation_type& impl,
        const ConstBufferSequence& buffers,
        Handler& handler, const IoExecutor& io_ex)
    {
      handle_service_.async_write_some(impl, buffers, handler, io_ex);
    }
  
    // Read some data. Returns the number of bytes received.
    template <typename MutableBufferSequence>
    size_t read_some(implementation_type& impl,
        const MutableBufferSequence& buffers, asio::error_code& ec)
    {
      return handle_service_.read_some(impl, buffers, ec);
    }
  
    // Start an asynchronous read. The buffer for the data being received must be
    // valid for the lifetime of the asynchronous operation.
    template <typename MutableBufferSequence,
        typename Handler, typename IoExecutor>
    void async_read_some(implementation_type& impl,
        const MutableBufferSequence& buffers,
        Handler& handler, const IoExecutor& io_ex)
    {
      handle_service_.async_read_some(impl, buffers, handler, io_ex);
    }
  
  private:
    // Function pointer type for storing a serial port option.
    typedef asio::error_code (*store_function_type)(
        const void*, ::DCB&, asio::error_code&);
  
    // Helper function template to store a serial port option.
    template <typename SettableSerialPortOption>
    static asio::error_code store_option(const void* option,
        ::DCB& storage, asio::error_code& ec)
    {
      static_cast<const SettableSerialPortOption*>(option)->store(storage, ec);
      return ec;
    }
  
    // Helper function to set a serial port option.
    ASIO_DECL asio::error_code do_set_option(
        implementation_type& impl, store_function_type store,
        const void* option, asio::error_code& ec);
  
    // Function pointer type for loading a serial port option.
    typedef asio::error_code (*load_function_type)(
        void*, const ::DCB&, asio::error_code&);
  
    // Helper function template to load a serial port option.
    template <typename GettableSerialPortOption>
    static asio::error_code load_option(void* option,
        const ::DCB& storage, asio::error_code& ec)
    {
      static_cast<GettableSerialPortOption*>(option)->load(storage, ec);
      return ec;
    }
  
    // Helper function to get a serial port option.
    ASIO_DECL asio::error_code do_get_option(
        const implementation_type& impl, load_function_type load,
        void* option, asio::error_code& ec) const;
  
    // The implementation used for initiating asynchronous operations.
    win_iocp_handle_service handle_service_;
  };
  
  } // namespace detail
  } // namespace asio
  
  #include "asio/detail/pop_options.hpp"
  
  #if defined(ASIO_HEADER_ONLY)
  # include "asio/detail/impl/win_iocp_serial_port_service.ipp"
  #endif // defined(ASIO_HEADER_ONLY)
  
  #endif // defined(ASIO_HAS_IOCP) && defined(ASIO_HAS_SERIAL_PORT)
  
  #endif // ASIO_DETAIL_WIN_IOCP_SERIAL_PORT_SERVICE_HPP
  