text: //
  // basic_socket_iostream.hpp
  // ~~~~~~~~~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2013 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_BASIC_SOCKET_IOSTREAM_HPP
  #define BOOST_ASIO_BASIC_SOCKET_IOSTREAM_HPP
  
  #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_NO_IOSTREAM)
  
  #include <istream>
  #include <ostream>
  #include <boost/asio/basic_socket_streambuf.hpp>
  #include <boost/asio/stream_socket_service.hpp>
  
  #if !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
  
  # include <boost/preprocessor/arithmetic/inc.hpp>
  # include <boost/preprocessor/repetition/enum_binary_params.hpp>
  # include <boost/preprocessor/repetition/enum_params.hpp>
  # include <boost/preprocessor/repetition/repeat_from_to.hpp>
  
  # if !defined(BOOST_ASIO_SOCKET_IOSTREAM_MAX_ARITY)
  #  define BOOST_ASIO_SOCKET_IOSTREAM_MAX_ARITY 5
  # endif // !defined(BOOST_ASIO_SOCKET_IOSTREAM_MAX_ARITY)
  
  // A macro that should expand to:
  //   template <typename T1, ..., typename Tn>
  //   explicit basic_socket_iostream(T1 x1, ..., Tn xn)
  //     : std::basic_iostream<char>(
  //         &this->detail::socket_iostream_base<
  //           Protocol, StreamSocketService, Time,
  //           TimeTraits, TimerService>::streambuf_)
  //   {
  //     if (rdbuf()->connect(x1, ..., xn) == 0)
  //       this->setstate(std::ios_base::failbit);
  //   }
  // This macro should only persist within this file.
  
  # define BOOST_ASIO_PRIVATE_CTR_DEF(z, n, data) \
    template <BOOST_PP_ENUM_PARAMS(n, typename T)> \
    explicit basic_socket_iostream(BOOST_PP_ENUM_BINARY_PARAMS(n, T, x)) \
      : std::basic_iostream<char>( \
          &this->detail::socket_iostream_base< \
            Protocol, StreamSocketService, Time, \
            TimeTraits, TimerService>::streambuf_) \
    { \
      this->setf(std::ios_base::unitbuf); \
      if (rdbuf()->connect(BOOST_PP_ENUM_PARAMS(n, x)) == 0) \
        this->setstate(std::ios_base::failbit); \
    } \
    /**/
  
  // A macro that should expand to:
  //   template <typename T1, ..., typename Tn>
  //   void connect(T1 x1, ..., Tn xn)
  //   {
  //     if (rdbuf()->connect(x1, ..., xn) == 0)
  //       this->setstate(std::ios_base::failbit);
  //   }
  // This macro should only persist within this file.
  
  # define BOOST_ASIO_PRIVATE_CONNECT_DEF(z, n, data) \
    template <BOOST_PP_ENUM_PARAMS(n, typename T)> \
    void connect(BOOST_PP_ENUM_BINARY_PARAMS(n, T, x)) \
    { \
      if (rdbuf()->connect(BOOST_PP_ENUM_PARAMS(n, x)) == 0) \
        this->setstate(std::ios_base::failbit); \
    } \
    /**/
  
  #endif // !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
  
  #include <boost/asio/detail/push_options.hpp>
  
  namespace boost {
  namespace asio {
  namespace detail {
  
  // A separate base class is used to ensure that the streambuf is initialised
  // prior to the basic_socket_iostream's basic_iostream base class.
  template <typename Protocol, typename StreamSocketService,
      typename Time, typename TimeTraits, typename TimerService>
  class socket_iostream_base
  {
  protected:
    basic_socket_streambuf<Protocol, StreamSocketService,
      Time, TimeTraits, TimerService> streambuf_;
  };
  
  }
  
  /// Iostream interface for a socket.
  template <typename Protocol,
      typename StreamSocketService = stream_socket_service<Protocol>,
  #if defined(BOOST_ASIO_HAS_BOOST_DATE_TIME) \
    || defined(GENERATING_DOCUMENTATION)
      typename Time = boost::posix_time::ptime,
      typename TimeTraits = boost::asio::time_traits<Time>,
      typename TimerService = deadline_timer_service<Time, TimeTraits> >
  #else
      typename Time = steady_timer::clock_type,
      typename TimeTraits = steady_timer::traits_type,
      typename TimerService = steady_timer::service_type>
  #endif
  class basic_socket_iostream
    : private detail::socket_iostream_base<Protocol,
          StreamSocketService, Time, TimeTraits, TimerService>,
      public std::basic_iostream<char>
  {
  private:
    // These typedefs are intended keep this class's implementation independent
    // of whether it's using Boost.DateTime, Boost.Chrono or std::chrono.
  #if defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
    typedef TimeTraits traits_helper;
  #else
    typedef detail::chrono_time_traits<Time, TimeTraits> traits_helper;
  #endif
  
  public:
    /// The endpoint type.
    typedef typename Protocol::endpoint endpoint_type;
  
  #if defined(GENERATING_DOCUMENTATION)
    /// The time type.
    typedef typename TimeTraits::time_type time_type;
  
    /// The duration type.
    typedef typename TimeTraits::duration_type duration_type;
  #else
    typedef typename traits_helper::time_type time_type;
    typedef typename traits_helper::duration_type duration_type;
  #endif
  
    /// Construct a basic_socket_iostream without establishing a connection.
    basic_socket_iostream()
      : std::basic_iostream<char>(
          &this->detail::socket_iostream_base<
            Protocol, StreamSocketService, Time,
            TimeTraits, TimerService>::streambuf_)
    {
      this->setf(std::ios_base::unitbuf);
    }
  
  #if defined(GENERATING_DOCUMENTATION)
    /// Establish a connection to an endpoint corresponding to a resolver query.
    /**
     * This constructor automatically establishes a connection based on the
     * supplied resolver query parameters. The arguments are used to construct
     * a resolver query object.
     */
    template <typename T1, ..., typename TN>
    explicit basic_socket_iostream(T1 t1, ..., TN tn);
  #elif defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
    template <typename... T>
    explicit basic_socket_iostream(T... x)
      : std::basic_iostream<char>(
          &this->detail::socket_iostream_base<
            Protocol, StreamSocketService, Time,
            TimeTraits, TimerService>::streambuf_)
    {
      this->setf(std::ios_base::unitbuf);
      if (rdbuf()->connect(x...) == 0)
        this->setstate(std::ios_base::failbit);
    }
  #else
    BOOST_PP_REPEAT_FROM_TO(
        1, BOOST_PP_INC(BOOST_ASIO_SOCKET_IOSTREAM_MAX_ARITY),
        BOOST_ASIO_PRIVATE_CTR_DEF, _ )
  #endif
  
  #if defined(GENERATING_DOCUMENTATION)
    /// Establish a connection to an endpoint corresponding to a resolver query.
    /**
     * This function automatically establishes a connection based on the supplied
     * resolver query parameters. The arguments are used to construct a resolver
     * query object.
     */
    template <typename T1, ..., typename TN>
    void connect(T1 t1, ..., TN tn);
  #elif defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
    template <typename... T>
    void connect(T... x)
    {
      if (rdbuf()->connect(x...) == 0)
        this->setstate(std::ios_base::failbit);
    }
  #else
    BOOST_PP_REPEAT_FROM_TO(
        1, BOOST_PP_INC(BOOST_ASIO_SOCKET_IOSTREAM_MAX_ARITY),
        BOOST_ASIO_PRIVATE_CONNECT_DEF, _ )
  #endif
  
    /// Close the connection.
    void close()
    {
      if (rdbuf()->close() == 0)
        this->setstate(std::ios_base::failbit);
    }
  
    /// Return a pointer to the underlying streambuf.
    basic_socket_streambuf<Protocol, StreamSocketService,
      Time, TimeTraits, TimerService>* rdbuf() const
    {
      return const_cast<basic_socket_streambuf<Protocol, StreamSocketService,
        Time, TimeTraits, TimerService>*>(
          &this->detail::socket_iostream_base<
            Protocol, StreamSocketService, Time,
            TimeTraits, TimerService>::streambuf_);
    }
  
    /// Get the last error associated with the stream.
    /**
     * @return An \c error_code corresponding to the last error from the stream.
     *
     * @par Example
     * To print the error associated with a failure to establish a connection:
     * @code tcp::iostream s("www.boost.org", "http");
     * if (!s)
     * {
     *   std::cout << "Error: " << s.error().message() << std::endl;
     * } @endcode
     */
    const boost::system::error_code& error() const
    {
      return rdbuf()->puberror();
    }
  
    /// Get the stream's expiry time as an absolute time.
    /**
     * @return An absolute time value representing the stream's expiry time.
     */
    time_type expires_at() const
    {
      return rdbuf()->expires_at();
    }
  
    /// Set the stream's expiry time as an absolute time.
    /**
     * This function sets the expiry time associated with the stream. Stream
     * operations performed after this time (where the operations cannot be
     * completed using the internal buffers) will fail with the error
     * boost::asio::error::operation_aborted.
     *
     * @param expiry_time The expiry time to be used for the stream.
     */
    void expires_at(const time_type& expiry_time)
    {
      rdbuf()->expires_at(expiry_time);
    }
  
    /// Get the timer's expiry time relative to now.
    /**
     * @return A relative time value representing the stream's expiry time.
     */
    duration_type expires_from_now() const
    {
      return rdbuf()->expires_from_now();
    }
  
    /// Set the stream's expiry time relative to now.
    /**
     * This function sets the expiry time associated with the stream. Stream
     * operations performed after this time (where the operations cannot be
     * completed using the internal buffers) will fail with the error
     * boost::asio::error::operation_aborted.
     *
     * @param expiry_time The expiry time to be used for the timer.
     */
    void expires_from_now(const duration_type& expiry_time)
    {
      rdbuf()->expires_from_now(expiry_time);
    }
  };
  
  } // namespace asio
  } // namespace boost
  
  #include <boost/asio/detail/pop_options.hpp>
  
  #if !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
  # undef BOOST_ASIO_PRIVATE_CTR_DEF
  # undef BOOST_ASIO_PRIVATE_CONNECT_DEF
  #endif // !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
  
  #endif // !defined(BOOST_ASIO_NO_IOSTREAM)
  
  #endif // BOOST_ASIO_BASIC_SOCKET_IOSTREAM_HPP
  