text: //
  // detail/socket_holder.hpp
  // ~~~~~~~~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2012 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_DETAIL_SOCKET_HOLDER_HPP
  #define BOOST_ASIO_DETAIL_SOCKET_HOLDER_HPP
  
  #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  # pragma once
  #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  
  #include <boost/asio/detail/config.hpp>
  #include <boost/asio/detail/noncopyable.hpp>
  #include <boost/asio/detail/socket_ops.hpp>
  
  #include <boost/asio/detail/push_options.hpp>
  
  namespace boost {
  namespace asio {
  namespace detail {
  
  // Implement the resource acquisition is initialisation idiom for sockets.
  class socket_holder
    : private noncopyable
  {
  public:
    // Construct as an uninitialised socket.
    socket_holder()
      : socket_(invalid_socket)
    {
    }
  
    // Construct to take ownership of the specified socket.
    explicit socket_holder(socket_type s)
      : socket_(s)
    {
    }
  
    // Destructor.
    ~socket_holder()
    {
      if (socket_ != invalid_socket)
      {
        boost::system::error_code ec;
        socket_ops::state_type state = 0;
        socket_ops::close(socket_, state, true, ec);
      }
    }
  
    // Get the underlying socket.
    socket_type get() const
    {
      return socket_;
    }
  
    // Reset to an uninitialised socket.
    void reset()
    {
      if (socket_ != invalid_socket)
      {
        boost::system::error_code ec;
        socket_ops::state_type state = 0;
        socket_ops::close(socket_, state, true, ec);
        socket_ = invalid_socket;
      }
    }
  
    // Reset to take ownership of the specified socket.
    void reset(socket_type s)
    {
      reset();
      socket_ = s;
    }
  
    // Release ownership of the socket.
    socket_type release()
    {
      socket_type tmp = socket_;
      socket_ = invalid_socket;
      return tmp;
    }
  
  private:
    // The underlying socket.
    socket_type socket_;
  };
  
  } // namespace detail
  } // namespace asio
  } // namespace boost
  
  #include <boost/asio/detail/pop_options.hpp>
  
  #endif // BOOST_ASIO_DETAIL_SOCKET_HOLDER_HPP
  