text: //
  // basic_serial_port.hpp
  // ~~~~~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2019 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_BASIC_SERIAL_PORT_HPP
  #define ASIO_BASIC_SERIAL_PORT_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_SERIAL_PORT) \
    || defined(GENERATING_DOCUMENTATION)
  
  #include <string>
  #include "asio/async_result.hpp"
  #include "asio/detail/handler_type_requirements.hpp"
  #include "asio/detail/io_object_impl.hpp"
  #include "asio/detail/non_const_lvalue.hpp"
  #include "asio/detail/throw_error.hpp"
  #include "asio/detail/type_traits.hpp"
  #include "asio/error.hpp"
  #include "asio/execution_context.hpp"
  #include "asio/executor.hpp"
  #include "asio/serial_port_base.hpp"
  #if defined(ASIO_HAS_IOCP)
  # include "asio/detail/win_iocp_serial_port_service.hpp"
  #else
  # include "asio/detail/reactive_serial_port_service.hpp"
  #endif
  
  #if defined(ASIO_HAS_MOVE)
  # include <utility>
  #endif // defined(ASIO_HAS_MOVE)
  
  #include "asio/detail/push_options.hpp"
  
  namespace asio {
  
  /// Provides serial port functionality.
  /**
   * The basic_serial_port class provides a wrapper over serial port
   * functionality.
   *
   * @par Thread Safety
   * @e Distinct @e objects: Safe.@n
   * @e Shared @e objects: Unsafe.
   */
  template <typename Executor = executor>
  class basic_serial_port
    : public serial_port_base
  {
  public:
    /// The type of the executor associated with the object.
    typedef Executor executor_type;
  
    /// The native representation of a serial port.
  #if defined(GENERATING_DOCUMENTATION)
    typedef implementation_defined native_handle_type;
  #elif defined(ASIO_HAS_IOCP)
    typedef detail::win_iocp_serial_port_service::native_handle_type
      native_handle_type;
  #else
    typedef detail::reactive_serial_port_service::native_handle_type
      native_handle_type;
  #endif
  
    /// A basic_basic_serial_port is always the lowest layer.
    typedef basic_serial_port lowest_layer_type;
  
    /// Construct a basic_serial_port without opening it.
    /**
     * This constructor creates a serial port without opening it.
     *
     * @param ex The I/O executor that the serial port will use, by default, to
     * dispatch handlers for any asynchronous operations performed on the
     * serial port.
     */
    explicit basic_serial_port(const executor_type& ex)
      : impl_(ex)
    {
    }
  
    /// Construct a basic_serial_port without opening it.
    /**
     * This constructor creates a serial port without opening it.
     *
     * @param context An execution context which provides the I/O executor that
     * the serial port will use, by default, to dispatch handlers for any
     * asynchronous operations performed on the serial port.
     */
    template <typename ExecutionContext>
    explicit basic_serial_port(ExecutionContext& context,
        typename enable_if<
          is_convertible<ExecutionContext&, execution_context&>::value,
          basic_serial_port
        >::type* = 0)
      : impl_(context)
    {
    }
  
    /// Construct and open a basic_serial_port.
    /**
     * This constructor creates and opens a serial port for the specified device
     * name.
     *
     * @param ex The I/O executor that the serial port will use, by default, to
     * dispatch handlers for any asynchronous operations performed on the
     * serial port.
     *
     * @param device The platform-specific device name for this serial
     * port.
     */
    basic_serial_port(const executor_type& ex, const char* device)
      : impl_(ex)
    {
      asio::error_code ec;
      impl_.get_service().open(impl_.get_implementation(), device, ec);
      asio::detail::throw_error(ec, "open");
    }
  
    /// Construct and open a basic_serial_port.
    /**
     * This constructor creates and opens a serial port for the specified device
     * name.
     *
     * @param context An execution context which provides the I/O executor that
     * the serial port will use, by default, to dispatch handlers for any
     * asynchronous operations performed on the serial port.
     *
     * @param device The platform-specific device name for this serial
     * port.
     */
    template <typename ExecutionContext>
    basic_serial_port(ExecutionContext& context, const char* device,
        typename enable_if<
          is_convertible<ExecutionContext&, execution_context&>::value
        >::type* = 0)
      : impl_(context)
    {
      asio::error_code ec;
      impl_.get_service().open(impl_.get_implementation(), device, ec);
      asio::detail::throw_error(ec, "open");
    }
  
    /// Construct and open a basic_serial_port.
    /**
     * This constructor creates and opens a serial port for the specified device
     * name.
     *
     * @param ex The I/O executor that the serial port will use, by default, to
     * dispatch handlers for any asynchronous operations performed on the
     * serial port.
     *
     * @param device The platform-specific device name for this serial
     * port.
     */
    basic_serial_port(const executor_type& ex, const std::string& device)
      : impl_(ex)
    {
      asio::error_code ec;
      impl_.get_service().open(impl_.get_implementation(), device, ec);
      asio::detail::throw_error(ec, "open");
    }
  
    /// Construct and open a basic_serial_port.
    /**
     * This constructor creates and opens a serial port for the specified device
     * name.
     *
     * @param context An execution context which provides the I/O executor that
     * the serial port will use, by default, to dispatch handlers for any
     * asynchronous operations performed on the serial port.
     *
     * @param device The platform-specific device name for this serial
     * port.
     */
    template <typename ExecutionContext>
    basic_serial_port(ExecutionContext& context, const std::string& device,
        typename enable_if<
          is_convertible<ExecutionContext&, execution_context&>::value
        >::type* = 0)
      : impl_(context)
    {
      asio::error_code ec;
      impl_.get_service().open(impl_.get_implementation(), device, ec);
      asio::detail::throw_error(ec, "open");
    }
  
    /// Construct a basic_serial_port on an existing native serial port.
    /**
     * This constructor creates a serial port object to hold an existing native
     * serial port.
     *
     * @param ex The I/O executor that the serial port will use, by default, to
     * dispatch handlers for any asynchronous operations performed on the
     * serial port.
     *
     * @param native_serial_port A native serial port.
     *
     * @throws asio::system_error Thrown on failure.
     */
    basic_serial_port(const executor_type& ex,
        const native_handle_type& native_serial_port)
      : impl_(ex)
    {
      asio::error_code ec;
      impl_.get_service().assign(impl_.get_implementation(),
          native_serial_port, ec);
      asio::detail::throw_error(ec, "assign");
    }
  
    /// Construct a basic_serial_port on an existing native serial port.
    /**
     * This constructor creates a serial port object to hold an existing native
     * serial port.
     *
     * @param context An execution context which provides the I/O executor that
     * the serial port will use, by default, to dispatch handlers for any
     * asynchronous operations performed on the serial port.
     *
     * @param native_serial_port A native serial port.
     *
     * @throws asio::system_error Thrown on failure.
     */
    template <typename ExecutionContext>
    basic_serial_port(ExecutionContext& context,
        const native_handle_type& native_serial_port,
        typename enable_if<
          is_convertible<ExecutionContext&, execution_context&>::value
        >::type* = 0)
      : impl_(context)
    {
      asio::error_code ec;
      impl_.get_service().assign(impl_.get_implementation(),
          native_serial_port, ec);
      asio::detail::throw_error(ec, "assign");
    }
  
  #if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
    /// Move-construct a basic_serial_port from another.
    /**
     * This constructor moves a serial port from one object to another.
     *
     * @param other The other basic_serial_port object from which the move will
     * occur.
     *
     * @note Following the move, the moved-from object is in the same state as if
     * constructed using the @c basic_serial_port(const executor_type&)
     * constructor.
     */
    basic_serial_port(basic_serial_port&& other)
      : impl_(std::move(other.impl_))
    {
    }
  
    /// Move-assign a basic_serial_port from another.
    /**
     * This assignment operator moves a serial port from one object to another.
     *
     * @param other The other basic_serial_port object from which the move will
     * occur.
     *
     * @note Following the move, the moved-from object is in the same state as if
     * constructed using the @c basic_serial_port(const executor_type&)
     * constructor.
     */
    basic_serial_port& operator=(basic_serial_port&& other)
    {
      impl_ = std::move(other.impl_);
      return *this;
    }
  #endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
  
    /// Destroys the serial port.
    /**
     * This function destroys the serial port, cancelling any outstanding
     * asynchronous wait operations associated with the serial port as if by
     * calling @c cancel.
     */
    ~basic_serial_port()
    {
    }
  
    /// Get the executor associated with the object.
    executor_type get_executor() ASIO_NOEXCEPT
    {
      return impl_.get_executor();
    }
  
    /// Get a reference to the lowest layer.
    /**
     * This function returns a reference to the lowest layer in a stack of
     * layers. Since a basic_serial_port cannot contain any further layers, it
     * simply returns a reference to itself.
     *
     * @return A reference to the lowest layer in the stack of layers. Ownership
     * is not transferred to the caller.
     */
    lowest_layer_type& lowest_layer()
    {
      return *this;
    }
  
    /// Get a const reference to the lowest layer.
    /**
     * This function returns a const reference to the lowest layer in a stack of
     * layers. Since a basic_serial_port cannot contain any further layers, it
     * simply returns a reference to itself.
     *
     * @return A const reference to the lowest layer in the stack of layers.
     * Ownership is not transferred to the caller.
     */
    const lowest_layer_type& lowest_layer() const
    {
      return *this;
    }
  
    /// Open the serial port using the specified device name.
    /**
     * This function opens the serial port for the specified device name.
     *
     * @param device The platform-specific device name.
     *
     * @throws asio::system_error Thrown on failure.
     */
    void open(const std::string& device)
    {
      asio::error_code ec;
      impl_.get_service().open(impl_.get_implementation(), device, ec);
      asio::detail::throw_error(ec, "open");
    }
  
    /// Open the serial port using the specified device name.
    /**
     * This function opens the serial port using the given platform-specific
     * device name.
     *
     * @param device The platform-specific device name.
     *
     * @param ec Set the indicate what error occurred, if any.
     */
    ASIO_SYNC_OP_VOID open(const std::string& device,
        asio::error_code& ec)
    {
      impl_.get_service().open(impl_.get_implementation(), device, ec);
      ASIO_SYNC_OP_VOID_RETURN(ec);
    }
  
    /// Assign an existing native serial port to the serial port.
    /*
     * This function opens the serial port to hold an existing native serial port.
     *
     * @param native_serial_port A native serial port.
     *
     * @throws asio::system_error Thrown on failure.
     */
    void assign(const native_handle_type& native_serial_port)
    {
      asio::error_code ec;
      impl_.get_service().assign(impl_.get_implementation(),
          native_serial_port, ec);
      asio::detail::throw_error(ec, "assign");
    }
  
    /// Assign an existing native serial port to the serial port.
    /*
     * This function opens the serial port to hold an existing native serial port.
     *
     * @param native_serial_port A native serial port.
     *
     * @param ec Set to indicate what error occurred, if any.
     */
    ASIO_SYNC_OP_VOID assign(const native_handle_type& native_serial_port,
        asio::error_code& ec)
    {
      impl_.get_service().assign(impl_.get_implementation(),
          native_serial_port, ec);
      ASIO_SYNC_OP_VOID_RETURN(ec);
    }
  
    /// Determine whether the serial port is open.
    bool is_open() const
    {
      return impl_.get_service().is_open(impl_.get_implementation());
    }
  
    /// Close the serial port.
    /**
     * This function is used to close the serial port. Any asynchronous read or
     * write operations will be cancelled immediately, and will complete with the
     * asio::error::operation_aborted error.
     *
     * @throws asio::system_error Thrown on failure.
     */
    void close()
    {
      asio::error_code ec;
      impl_.get_service().close(impl_.get_implementation(), ec);
      asio::detail::throw_error(ec, "close");
    }
  
    /// Close the serial port.
    /**
     * This function is used to close the serial port. Any asynchronous read or
     * write operations will be cancelled immediately, and will complete with the
     * asio::error::operation_aborted error.
     *
     * @param ec Set to indicate what error occurred, if any.
     */
    ASIO_SYNC_OP_VOID close(asio::error_code& ec)
    {
      impl_.get_service().close(impl_.get_implementation(), ec);
      ASIO_SYNC_OP_VOID_RETURN(ec);
    }
  
    /// Get the native serial port representation.
    /**
     * This function may be used to obtain the underlying representation of the
     * serial port. This is intended to allow access to native serial port
     * functionality that is not otherwise provided.
     */
    native_handle_type native_handle()
    {
      return impl_.get_service().native_handle(impl_.get_implementation());
    }
  
    /// Cancel all asynchronous operations associated with the serial port.
    /**
     * This function causes all outstanding asynchronous read or write operations
     * to finish immediately, and the handlers for cancelled operations will be
     * passed the asio::error::operation_aborted error.
     *
     * @throws asio::system_error Thrown on failure.
     */
    void cancel()
    {
      asio::error_code ec;
      impl_.get_service().cancel(impl_.get_implementation(), ec);
      asio::detail::throw_error(ec, "cancel");
    }
  
    /// Cancel all asynchronous operations associated with the serial port.
    /**
     * This function causes all outstanding asynchronous read or write operations
     * to finish immediately, and the handlers for cancelled operations will be
     * passed the asio::error::operation_aborted error.
     *
     * @param ec Set to indicate what error occurred, if any.
     */
    ASIO_SYNC_OP_VOID cancel(asio::error_code& ec)
    {
      impl_.get_service().cancel(impl_.get_implementation(), ec);
      ASIO_SYNC_OP_VOID_RETURN(ec);
    }
  
    /// Send a break sequence to the serial port.
    /**
     * This function causes a break sequence of platform-specific duration to be
     * sent out the serial port.
     *
     * @throws asio::system_error Thrown on failure.
     */
    void send_break()
    {
      asio::error_code ec;
      impl_.get_service().send_break(impl_.get_implementation(), ec);
      asio::detail::throw_error(ec, "send_break");
    }
  
    /// Send a break sequence to the serial port.
    /**
     * This function causes a break sequence of platform-specific duration to be
     * sent out the serial port.
     *
     * @param ec Set to indicate what error occurred, if any.
     */
    ASIO_SYNC_OP_VOID send_break(asio::error_code& ec)
    {
      impl_.get_service().send_break(impl_.get_implementation(), ec);
      ASIO_SYNC_OP_VOID_RETURN(ec);
    }
  
    /// Set an option on the serial port.
    /**
     * This function is used to set an option on the serial port.
     *
     * @param option The option value to be set on the serial port.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @sa SettableSerialPortOption @n
     * asio::serial_port_base::baud_rate @n
     * asio::serial_port_base::flow_control @n
     * asio::serial_port_base::parity @n
     * asio::serial_port_base::stop_bits @n
     * asio::serial_port_base::character_size
     */
    template <typename SettableSerialPortOption>
    void set_option(const SettableSerialPortOption& option)
    {
      asio::error_code ec;
      impl_.get_service().set_option(impl_.get_implementation(), option, ec);
      asio::detail::throw_error(ec, "set_option");
    }
  
    /// Set an option on the serial port.
    /**
     * This function is used to set an option on the serial port.
     *
     * @param option The option value to be set on the serial port.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @sa SettableSerialPortOption @n
     * asio::serial_port_base::baud_rate @n
     * asio::serial_port_base::flow_control @n
     * asio::serial_port_base::parity @n
     * asio::serial_port_base::stop_bits @n
     * asio::serial_port_base::character_size
     */
    template <typename SettableSerialPortOption>
    ASIO_SYNC_OP_VOID set_option(const SettableSerialPortOption& option,
        asio::error_code& ec)
    {
      impl_.get_service().set_option(impl_.get_implementation(), option, ec);
      ASIO_SYNC_OP_VOID_RETURN(ec);
    }
  
    /// Get an option from the serial port.
    /**
     * This function is used to get the current value of an option on the serial
     * port.
     *
     * @param option The option value to be obtained from the serial port.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @sa GettableSerialPortOption @n
     * asio::serial_port_base::baud_rate @n
     * asio::serial_port_base::flow_control @n
     * asio::serial_port_base::parity @n
     * asio::serial_port_base::stop_bits @n
     * asio::serial_port_base::character_size
     */
    template <typename GettableSerialPortOption>
    void get_option(GettableSerialPortOption& option)
    {
      asio::error_code ec;
      impl_.get_service().get_option(impl_.get_implementation(), option, ec);
      asio::detail::throw_error(ec, "get_option");
    }
  
    /// Get an option from the serial port.
    /**
     * This function is used to get the current value of an option on the serial
     * port.
     *
     * @param option The option value to be obtained from the serial port.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @sa GettableSerialPortOption @n
     * asio::serial_port_base::baud_rate @n
     * asio::serial_port_base::flow_control @n
     * asio::serial_port_base::parity @n
     * asio::serial_port_base::stop_bits @n
     * asio::serial_port_base::character_size
     */
    template <typename GettableSerialPortOption>
    ASIO_SYNC_OP_VOID get_option(GettableSerialPortOption& option,
        asio::error_code& ec)
    {
      impl_.get_service().get_option(impl_.get_implementation(), option, ec);
      ASIO_SYNC_OP_VOID_RETURN(ec);
    }
  
    /// Write some data to the serial port.
    /**
     * This function is used to write data to the serial port. The function call
     * will block until one or more bytes of the data has been written
     * successfully, or until an error occurs.
     *
     * @param buffers One or more data buffers to be written to the serial port.
     *
     * @returns The number of bytes written.
     *
     * @throws asio::system_error Thrown on failure. An error code of
     * asio::error::eof indicates that the connection was closed by the
     * peer.
     *
     * @note The write_some operation may not transmit all of the data to the
     * peer. Consider using the @ref write function if you need to ensure that
     * all data is written before the blocking operation completes.
     *
     * @par Example
     * To write a single data buffer use the @ref buffer function as follows:
     * @code
     * basic_serial_port.write_some(asio::buffer(data, size));
     * @endcode
     * See the @ref buffer documentation for information on writing multiple
     * buffers in one go, and how to use it with arrays, boost::array or
     * std::vector.
     */
    template <typename ConstBufferSequence>
    std::size_t write_some(const ConstBufferSequence& buffers)
    {
      asio::error_code ec;
      std::size_t s = impl_.get_service().write_some(
          impl_.get_implementation(), buffers, ec);
      asio::detail::throw_error(ec, "write_some");
      return s;
    }
  
    /// Write some data to the serial port.
    /**
     * This function is used to write data to the serial port. The function call
     * will block until one or more bytes of the data has been written
     * successfully, or until an error occurs.
     *
     * @param buffers One or more data buffers to be written to the serial port.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @returns The number of bytes written. Returns 0 if an error occurred.
     *
     * @note The write_some operation may not transmit all of the data to the
     * peer. Consider using the @ref write function if you need to ensure that
     * all data is written before the blocking operation completes.
     */
    template <typename ConstBufferSequence>
    std::size_t write_some(const ConstBufferSequence& buffers,
        asio::error_code& ec)
    {
      return impl_.get_service().write_some(
          impl_.get_implementation(), buffers, ec);
    }
  
    /// Start an asynchronous write.
    /**
     * This function is used to asynchronously write data to the serial port.
     * The function call always returns immediately.
     *
     * @param buffers One or more data buffers to be written to the serial port.
     * Although the buffers object may be copied as necessary, ownership of the
     * underlying memory blocks is retained by the caller, which must guarantee
     * that they remain valid until the handler is called.
     *
     * @param handler The handler to be called when the write operation completes.
     * Copies will be made of the handler as required. The function signature of
     * the handler must be:
     * @code void handler(
     *   const asio::error_code& error, // Result of operation.
     *   std::size_t bytes_transferred           // Number of bytes written.
     * ); @endcode
     * Regardless of whether the asynchronous operation completes immediately or
     * not, the handler will not be invoked from within this function. On
     * immediate completion, invocation of the handler will be performed in a
     * manner equivalent to using asio::post().
     *
     * @note The write operation may not transmit all of the data to the peer.
     * Consider using the @ref async_write function if you need to ensure that all
     * data is written before the asynchronous operation completes.
     *
     * @par Example
     * To write a single data buffer use the @ref buffer function as follows:
     * @code
     * basic_serial_port.async_write_some(
     *     asio::buffer(data, size), handler);
     * @endcode
     * See the @ref buffer documentation for information on writing multiple
     * buffers in one go, and how to use it with arrays, boost::array or
     * std::vector.
     */
    template <typename ConstBufferSequence, typename WriteHandler>
    ASIO_INITFN_RESULT_TYPE(WriteHandler,
        void (asio::error_code, std::size_t))
    async_write_some(const ConstBufferSequence& buffers,
        ASIO_MOVE_ARG(WriteHandler) handler)
    {
      return async_initiate<WriteHandler,
        void (asio::error_code, std::size_t)>(
          initiate_async_write_some(), handler, this, buffers);
    }
  
    /// Read some data from the serial port.
    /**
     * This function is used to read data from the serial port. The function
     * call will block until one or more bytes of data has been read successfully,
     * or until an error occurs.
     *
     * @param buffers One or more buffers into which the data will be read.
     *
     * @returns The number of bytes read.
     *
     * @throws asio::system_error Thrown on failure. An error code of
     * asio::error::eof indicates that the connection was closed by the
     * peer.
     *
     * @note The read_some operation may not read all of the requested number of
     * bytes. Consider using the @ref read function if you need to ensure that
     * the requested amount of data is read before the blocking operation
     * completes.
     *
     * @par Example
     * To read into a single data buffer use the @ref buffer function as follows:
     * @code
     * basic_serial_port.read_some(asio::buffer(data, size));
     * @endcode
     * See the @ref buffer documentation for information on reading into multiple
     * buffers in one go, and how to use it with arrays, boost::array or
     * std::vector.
     */
    template <typename MutableBufferSequence>
    std::size_t read_some(const MutableBufferSequence& buffers)
    {
      asio::error_code ec;
      std::size_t s = impl_.get_service().read_some(
          impl_.get_implementation(), buffers, ec);
      asio::detail::throw_error(ec, "read_some");
      return s;
    }
  
    /// Read some data from the serial port.
    /**
     * This function is used to read data from the serial port. The function
     * call will block until one or more bytes of data has been read successfully,
     * or until an error occurs.
     *
     * @param buffers One or more buffers into which the data will be read.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @returns The number of bytes read. Returns 0 if an error occurred.
     *
     * @note The read_some operation may not read all of the requested number of
     * bytes. Consider using the @ref read function if you need to ensure that
     * the requested amount of data is read before the blocking operation
     * completes.
     */
    template <typename MutableBufferSequence>
    std::size_t read_some(const MutableBufferSequence& buffers,
        asio::error_code& ec)
    {
      return impl_.get_service().read_some(
          impl_.get_implementation(), buffers, ec);
    }
  
    /// Start an asynchronous read.
    /**
     * This function is used to asynchronously read data from the serial port.
     * The function call always returns immediately.
     *
     * @param buffers One or more buffers into which the data will be read.
     * Although the buffers object may be copied as necessary, ownership of the
     * underlying memory blocks is retained by the caller, which must guarantee
     * that they remain valid until the handler is called.
     *
     * @param handler The handler to be called when the read operation completes.
     * Copies will be made of the handler as required. The function signature of
     * the handler must be:
     * @code void handler(
     *   const asio::error_code& error, // Result of operation.
     *   std::size_t bytes_transferred           // Number of bytes read.
     * ); @endcode
     * Regardless of whether the asynchronous operation completes immediately or
     * not, the handler will not be invoked from within this function. On
     * immediate completion, invocation of the handler will be performed in a
     * manner equivalent to using asio::post().
     *
     * @note The read operation may not read all of the requested number of bytes.
     * Consider using the @ref async_read function if you need to ensure that the
     * requested amount of data is read before the asynchronous operation
     * completes.
     *
     * @par Example
     * To read into a single data buffer use the @ref buffer function as follows:
     * @code
     * basic_serial_port.async_read_some(
     *     asio::buffer(data, size), handler);
     * @endcode
     * See the @ref buffer documentation for information on reading into multiple
     * buffers in one go, and how to use it with arrays, boost::array or
     * std::vector.
     */
    template <typename MutableBufferSequence, typename ReadHandler>
    ASIO_INITFN_RESULT_TYPE(ReadHandler,
        void (asio::error_code, std::size_t))
    async_read_some(const MutableBufferSequence& buffers,
        ASIO_MOVE_ARG(ReadHandler) handler)
    {
      return async_initiate<ReadHandler,
        void (asio::error_code, std::size_t)>(
          initiate_async_read_some(), handler, this, buffers);
    }
  
  private:
    // Disallow copying and assignment.
    basic_serial_port(const basic_serial_port&) ASIO_DELETED;
    basic_serial_port& operator=(const basic_serial_port&) ASIO_DELETED;
  
    struct initiate_async_write_some
    {
      template <typename WriteHandler, typename ConstBufferSequence>
      void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
          basic_serial_port* self, const ConstBufferSequence& buffers) const
      {
        // If you get an error on the following line it means that your handler
        // does not meet the documented type requirements for a WriteHandler.
        ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
  
        detail::non_const_lvalue<WriteHandler> handler2(handler);
        self->impl_.get_service().async_write_some(
            self->impl_.get_implementation(), buffers, handler2.value,
            self->impl_.get_implementation_executor());
      }
    };
  
    struct initiate_async_read_some
    {
      template <typename ReadHandler, typename MutableBufferSequence>
      void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
          basic_serial_port* self, const MutableBufferSequence& buffers) const
      {
        // If you get an error on the following line it means that your handler
        // does not meet the documented type requirements for a ReadHandler.
        ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
  
        detail::non_const_lvalue<ReadHandler> handler2(handler);
        self->impl_.get_service().async_read_some(
            self->impl_.get_implementation(), buffers, handler2.value,
            self->impl_.get_implementation_executor());
      }
    };
  
  #if defined(ASIO_HAS_IOCP)
    detail::io_object_impl<detail::win_iocp_serial_port_service, Executor> impl_;
  #else
    detail::io_object_impl<detail::reactive_serial_port_service, Executor> impl_;
  #endif
  };
  
  } // namespace asio
  
  #include "asio/detail/pop_options.hpp"
  
  #endif // defined(ASIO_HAS_SERIAL_PORT)
         //   || defined(GENERATING_DOCUMENTATION)
  
  #endif // ASIO_BASIC_SERIAL_PORT_HPP
  