daemon/face/tcp-channel-factory.hpp

/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/**
 * Copyright (C) 2014 Named Data Networking Project
 * See COPYING for copyright and distribution information.
 */

#ifndef NFD_FACE_TCP_CHANNEL_FACTORY_HPP
#define NFD_FACE_TCP_CHANNEL_FACTORY_HPP

#include "channel-factory.hpp"
#include "tcp-channel.hpp"

namespace nfd {

class TcpChannelFactory : public ChannelFactory<tcp::Endpoint, TcpChannel>
{
public:
  /**
   * \brief Exception of TcpChannelFactory
   */
  struct Error : public ChannelFactory<tcp::Endpoint, TcpChannel>::Error
  {
    Error(const std::string& what)
      : ChannelFactory<tcp::Endpoint, TcpChannel>::Error(what)
    {
    }
  };

  explicit
  TcpChannelFactory(boost::asio::io_service& ioService);

  /**
   * \brief Create TCP-based channel using tcp::Endpoint
   *
   * tcp::Endpoint is really an alias for boost::asio::ip::tcp::endpoint.
   *
   * If this method called twice with the same endpoint, only one channel
   * will be created.  The second call will just retrieve the existing
   * channel.
   *
   * \returns always a valid pointer to a TcpChannel object, an exception
   *          is thrown if it cannot be created.
   *
   * \throws TcpChannelFactory::Error
   *
   * \see http://www.boost.org/doc/libs/1_42_0/doc/html/boost_asio/reference/ip__tcp/endpoint.html
   *      for details on ways to create tcp::Endpoint
   */
  shared_ptr<TcpChannel>
  create(const tcp::Endpoint& localEndpoint);

  /**
   * \brief Create TCP-based channel using specified host and port number
   *
   * This method will attempt to resolve the provided host and port numbers
   * and will throw TcpChannelFactory::Error when channel cannot be created.
   *
   * Note that this call will **BLOCK** until resolution is done or failed.
   *
   * \throws TcpChannelFactory::Error
   */
  shared_ptr<TcpChannel>
  create(const std::string& localHost, const std::string& localPort);

private:
  /**
   * \brief Look up TcpChannel using specified local endpoint
   *
   * \returns shared pointer to the existing TcpChannel object
   *          or empty shared pointer when such channel does not exist 
   *
   * \throws never
   */
  shared_ptr<TcpChannel>
  find(const tcp::Endpoint& localEndpoint);

private:
  boost::asio::io_service& m_ioService;
};

} // namespace nfd

#endif // NFD_FACE_TCP_CHANNEL_FACTORY_HPP