text: //
  // generic/seq_packet_protocol.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_GENERIC_SEQ_PACKET_PROTOCOL_HPP
  #define BOOST_ASIO_GENERIC_SEQ_PACKET_PROTOCOL_HPP
  
  #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  # pragma once
  #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  
  #include <boost/asio/detail/config.hpp>
  
  #include <typeinfo>
  #include <boost/asio/basic_seq_packet_socket.hpp>
  #include <boost/asio/detail/socket_types.hpp>
  #include <boost/asio/detail/throw_exception.hpp>
  #include <boost/asio/generic/basic_endpoint.hpp>
  
  #include <boost/asio/detail/push_options.hpp>
  
  namespace boost {
  namespace asio {
  namespace generic {
  
  /// Encapsulates the flags needed for a generic sequenced packet socket.
  /**
   * The boost::asio::generic::seq_packet_protocol class contains flags necessary
   * for seq_packet-oriented sockets of any address family and protocol.
   *
   * @par Examples
   * Constructing using a native address family and socket protocol:
   * @code seq_packet_protocol p(AF_INET, IPPROTO_SCTP); @endcode
   *
   * @par Thread Safety
   * @e Distinct @e objects: Safe.@n
   * @e Shared @e objects: Safe.
   *
   * @par Concepts:
   * Protocol.
   */
  class seq_packet_protocol
  {
  public:
    /// Construct a protocol object for a specific address family and protocol.
    seq_packet_protocol(int address_family, int socket_protocol)
      : family_(address_family),
        protocol_(socket_protocol)
    {
    }
  
    /// Construct a generic protocol object from a specific protocol.
    /**
     * @throws @c bad_cast Thrown if the source protocol is not based around
     * sequenced packets.
     */
    template <typename Protocol>
    seq_packet_protocol(const Protocol& source_protocol)
      : family_(source_protocol.family()),
        protocol_(source_protocol.protocol())
    {
      if (source_protocol.type() != type())
      {
        std::bad_cast ex;
        boost::asio::detail::throw_exception(ex);
      }
    }
  
    /// Obtain an identifier for the type of the protocol.
    int type() const
    {
      return SOCK_SEQPACKET;
    }
  
    /// Obtain an identifier for the protocol.
    int protocol() const
    {
      return protocol_;
    }
  
    /// Obtain an identifier for the protocol family.
    int family() const
    {
      return family_;
    }
  
    /// Compare two protocols for equality.
    friend bool operator==(const seq_packet_protocol& p1,
        const seq_packet_protocol& p2)
    {
      return p1.family_ == p2.family_ && p1.protocol_ == p2.protocol_;
    }
  
    /// Compare two protocols for inequality.
    friend bool operator!=(const seq_packet_protocol& p1,
        const seq_packet_protocol& p2)
    {
      return !(p1 == p2);
    }
  
    /// The type of an endpoint.
    typedef basic_endpoint<seq_packet_protocol> endpoint;
  
    /// The generic socket type.
    typedef basic_seq_packet_socket<seq_packet_protocol> socket;
  
  private:
    int family_;
    int protocol_;
  };
  
  } // namespace generic
  } // namespace asio
  } // namespace boost
  
  #include <boost/asio/detail/pop_options.hpp>
  
  #endif // BOOST_ASIO_GENERIC_SEQ_PACKET_PROTOCOL_HPP
  