text: //
  // detail/null_socket_service.hpp
  // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2018 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_NULL_SOCKET_SERVICE_HPP
  #define ASIO_DETAIL_NULL_SOCKET_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_WINDOWS_RUNTIME)
  
  #include "asio/buffer.hpp"
  #include "asio/error.hpp"
  #include "asio/io_context.hpp"
  #include "asio/socket_base.hpp"
  #include "asio/detail/bind_handler.hpp"
  
  #include "asio/detail/push_options.hpp"
  
  namespace asio {
  namespace detail {
  
  template <typename Protocol>
  class null_socket_service :
    public service_base<null_socket_service<Protocol> >
  {
  public:
    // The protocol type.
    typedef Protocol protocol_type;
  
    // The endpoint type.
    typedef typename Protocol::endpoint endpoint_type;
  
    // The native type of a socket.
    typedef int native_handle_type;
  
    // The implementation type of the socket.
    struct implementation_type
    {
    };
  
    // Constructor.
    null_socket_service(asio::io_context& io_context)
      : service_base<null_socket_service<Protocol> >(io_context),
        io_context_(io_context)
    {
    }
  
    // Destroy all user-defined handler objects owned by the service.
    void shutdown()
    {
    }
  
    // Construct a new socket implementation.
    void construct(implementation_type&)
    {
    }
  
    // Move-construct a new socket implementation.
    void move_construct(implementation_type&, implementation_type&)
    {
    }
  
    // Move-assign from another socket implementation.
    void move_assign(implementation_type&,
        null_socket_service&, implementation_type&)
    {
    }
  
    // Move-construct a new socket implementation from another protocol type.
    template <typename Protocol1>
    void converting_move_construct(implementation_type&,
        null_socket_service<Protocol1>&,
        typename null_socket_service<Protocol1>::implementation_type&)
    {
    }
  
    // Destroy a socket implementation.
    void destroy(implementation_type&)
    {
    }
  
    // Open a new socket implementation.
    asio::error_code open(implementation_type&,
        const protocol_type&, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Assign a native socket to a socket implementation.
    asio::error_code assign(implementation_type&, const protocol_type&,
        const native_handle_type&, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Determine whether the socket is open.
    bool is_open(const implementation_type&) const
    {
      return false;
    }
  
    // Destroy a socket implementation.
    asio::error_code close(implementation_type&,
        asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Release ownership of the socket.
    native_handle_type release(implementation_type&,
        asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Get the native socket representation.
    native_handle_type native_handle(implementation_type&)
    {
      return 0;
    }
  
    // Cancel all operations associated with the socket.
    asio::error_code cancel(implementation_type&,
        asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Determine whether the socket is at the out-of-band data mark.
    bool at_mark(const implementation_type&,
        asio::error_code& ec) const
    {
      ec = asio::error::operation_not_supported;
      return false;
    }
  
    // Determine the number of bytes available for reading.
    std::size_t available(const implementation_type&,
        asio::error_code& ec) const
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Place the socket into the state where it will listen for new connections.
    asio::error_code listen(implementation_type&,
        int, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Perform an IO control command on the socket.
    template <typename IO_Control_Command>
    asio::error_code io_control(implementation_type&,
        IO_Control_Command&, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Gets the non-blocking mode of the socket.
    bool non_blocking(const implementation_type&) const
    {
      return false;
    }
  
    // Sets the non-blocking mode of the socket.
    asio::error_code non_blocking(implementation_type&,
        bool, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Gets the non-blocking mode of the native socket implementation.
    bool native_non_blocking(const implementation_type&) const
    {
      return false;
    }
  
    // Sets the non-blocking mode of the native socket implementation.
    asio::error_code native_non_blocking(implementation_type&,
        bool, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Disable sends or receives on the socket.
    asio::error_code shutdown(implementation_type&,
        socket_base::shutdown_type, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Bind the socket to the specified local endpoint.
    asio::error_code bind(implementation_type&,
        const endpoint_type&, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Set a socket option.
    template <typename Option>
    asio::error_code set_option(implementation_type&,
        const Option&, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Set a socket option.
    template <typename Option>
    asio::error_code get_option(const implementation_type&,
        Option&, asio::error_code& ec) const
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Get the local endpoint.
    endpoint_type local_endpoint(const implementation_type&,
        asio::error_code& ec) const
    {
      ec = asio::error::operation_not_supported;
      return endpoint_type();
    }
  
    // Get the remote endpoint.
    endpoint_type remote_endpoint(const implementation_type&,
        asio::error_code& ec) const
    {
      ec = asio::error::operation_not_supported;
      return endpoint_type();
    }
  
    // Send the given data to the peer.
    template <typename ConstBufferSequence>
    std::size_t send(implementation_type&, const ConstBufferSequence&,
        socket_base::message_flags, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Wait until data can be sent without blocking.
    std::size_t send(implementation_type&, const null_buffers&,
        socket_base::message_flags, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Start an asynchronous send. The data being sent must be valid for the
    // lifetime of the asynchronous operation.
    template <typename ConstBufferSequence, typename Handler>
    void async_send(implementation_type&, const ConstBufferSequence&,
        socket_base::message_flags, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      const std::size_t bytes_transferred = 0;
      io_context_.post(detail::bind_handler(handler, ec, bytes_transferred));
    }
  
    // Start an asynchronous wait until data can be sent without blocking.
    template <typename Handler>
    void async_send(implementation_type&, const null_buffers&,
        socket_base::message_flags, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      const std::size_t bytes_transferred = 0;
      io_context_.post(detail::bind_handler(handler, ec, bytes_transferred));
    }
  
    // Receive some data from the peer. Returns the number of bytes received.
    template <typename MutableBufferSequence>
    std::size_t receive(implementation_type&, const MutableBufferSequence&,
        socket_base::message_flags, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Wait until data can be received without blocking.
    std::size_t receive(implementation_type&, const null_buffers&,
        socket_base::message_flags, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Start an asynchronous receive. The buffer for the data being received
    // must be valid for the lifetime of the asynchronous operation.
    template <typename MutableBufferSequence, typename Handler>
    void async_receive(implementation_type&, const MutableBufferSequence&,
        socket_base::message_flags, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      const std::size_t bytes_transferred = 0;
      io_context_.post(detail::bind_handler(handler, ec, bytes_transferred));
    }
  
    // Wait until data can be received without blocking.
    template <typename Handler>
    void async_receive(implementation_type&, const null_buffers&,
        socket_base::message_flags, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      const std::size_t bytes_transferred = 0;
      io_context_.post(detail::bind_handler(handler, ec, bytes_transferred));
    }
  
    // Receive some data with associated flags. Returns the number of bytes
    // received.
    template <typename MutableBufferSequence>
    std::size_t receive_with_flags(implementation_type&,
        const MutableBufferSequence&, socket_base::message_flags,
        socket_base::message_flags&, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Wait until data can be received without blocking.
    std::size_t receive_with_flags(implementation_type&,
        const null_buffers&, socket_base::message_flags,
        socket_base::message_flags&, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Start an asynchronous receive. The buffer for the data being received
    // must be valid for the lifetime of the asynchronous operation.
    template <typename MutableBufferSequence, typename Handler>
    void async_receive_with_flags(implementation_type&,
        const MutableBufferSequence&, socket_base::message_flags,
        socket_base::message_flags&, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      const std::size_t bytes_transferred = 0;
      io_context_.post(detail::bind_handler(handler, ec, bytes_transferred));
    }
  
    // Wait until data can be received without blocking.
    template <typename Handler>
    void async_receive_with_flags(implementation_type&,
        const null_buffers&, socket_base::message_flags,
        socket_base::message_flags&, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      const std::size_t bytes_transferred = 0;
      io_context_.post(detail::bind_handler(handler, ec, bytes_transferred));
    }
  
    // Send a datagram to the specified endpoint. Returns the number of bytes
    // sent.
    template <typename ConstBufferSequence>
    std::size_t send_to(implementation_type&, const ConstBufferSequence&,
        const endpoint_type&, socket_base::message_flags,
        asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Wait until data can be sent without blocking.
    std::size_t send_to(implementation_type&, const null_buffers&,
        const endpoint_type&, socket_base::message_flags,
        asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Start an asynchronous send. The data being sent must be valid for the
    // lifetime of the asynchronous operation.
    template <typename ConstBufferSequence, typename Handler>
    void async_send_to(implementation_type&, const ConstBufferSequence&,
        const endpoint_type&, socket_base::message_flags,
        Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      const std::size_t bytes_transferred = 0;
      io_context_.post(detail::bind_handler(handler, ec, bytes_transferred));
    }
  
    // Start an asynchronous wait until data can be sent without blocking.
    template <typename Handler>
    void async_send_to(implementation_type&, const null_buffers&,
        const endpoint_type&, socket_base::message_flags, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      const std::size_t bytes_transferred = 0;
      io_context_.post(detail::bind_handler(handler, ec, bytes_transferred));
    }
  
    // Receive a datagram with the endpoint of the sender. Returns the number of
    // bytes received.
    template <typename MutableBufferSequence>
    std::size_t receive_from(implementation_type&, const MutableBufferSequence&,
        endpoint_type&, socket_base::message_flags,
        asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Wait until data can be received without blocking.
    std::size_t receive_from(implementation_type&, const null_buffers&,
        endpoint_type&, socket_base::message_flags,
        asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return 0;
    }
  
    // Start an asynchronous receive. The buffer for the data being received and
    // the sender_endpoint object must both be valid for the lifetime of the
    // asynchronous operation.
    template <typename MutableBufferSequence, typename Handler>
    void async_receive_from(implementation_type&,
        const MutableBufferSequence&, endpoint_type&,
        socket_base::message_flags, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      const std::size_t bytes_transferred = 0;
      io_context_.post(detail::bind_handler(handler, ec, bytes_transferred));
    }
  
    // Wait until data can be received without blocking.
    template <typename Handler>
    void async_receive_from(implementation_type&,
        const null_buffers&, endpoint_type&,
        socket_base::message_flags, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      const std::size_t bytes_transferred = 0;
      io_context_.post(detail::bind_handler(handler, ec, bytes_transferred));
    }
  
    // Accept a new connection.
    template <typename Socket>
    asio::error_code accept(implementation_type&,
        Socket&, endpoint_type*, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Start an asynchronous accept. The peer and peer_endpoint objects
    // must be valid until the accept's handler is invoked.
    template <typename Socket, typename Handler>
    void async_accept(implementation_type&, Socket&,
        endpoint_type*, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      io_context_.post(detail::bind_handler(handler, ec));
    }
  
    // Connect the socket to the specified endpoint.
    asio::error_code connect(implementation_type&,
        const endpoint_type&, asio::error_code& ec)
    {
      ec = asio::error::operation_not_supported;
      return ec;
    }
  
    // Start an asynchronous connect.
    template <typename Handler>
    void async_connect(implementation_type&,
        const endpoint_type&, Handler& handler)
    {
      asio::error_code ec = asio::error::operation_not_supported;
      io_context_.post(detail::bind_handler(handler, ec));
    }
  
  private:
    asio::io_context& io_context_;
  };
  
  } // namespace detail
  } // namespace asio
  
  #include "asio/detail/pop_options.hpp"
  
  #endif // defined(ASIO_WINDOWS_RUNTIME)
  
  #endif // ASIO_DETAIL_NULL_SOCKET_SERVICE_HPP
  