ndn-fib-entry.h

/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
/*
 * Copyright (c) 2011 University of California, Los Angeles
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation;
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
 */

#ifndef _NDN_FIB_ENTRY_H_
#define _NDN_FIB_ENTRY_H_

#include "ns3/ptr.h"
#include "ns3/nstime.h"
#include "ns3/ndn-face.h"
#include "ns3/ndn-name.h"
#include "ns3/ndn-limits.h"
#include "ns3/traced-value.h"

#include <boost/multi_index_container.hpp>
#include <boost/multi_index/tag.hpp>
#include <boost/multi_index/ordered_index.hpp>
#include <boost/multi_index/composite_key.hpp>
#include <boost/multi_index/hashed_index.hpp>
#include <boost/multi_index/random_access_index.hpp>
#include <boost/multi_index/member.hpp>
#include <boost/multi_index/mem_fun.hpp>

namespace ns3 {
namespace ndn {

class Name;
typedef Name NameComponents;

class Fib;

namespace fib {

class FaceMetric
{
public:
  enum Status { NDN_FIB_GREEN = 1,
                NDN_FIB_YELLOW = 2,
                NDN_FIB_RED = 3 };
public:
  FaceMetric (Ptr<Face> face, int32_t cost)
    : m_face (face)
    , m_status (NDN_FIB_YELLOW)
    , m_routingCost (cost)
    , m_sRtt   (Seconds (0))
    , m_rttVar (Seconds (0))
    , m_realDelay (Seconds (0))
  { }

  bool
  operator< (const FaceMetric &fm) const { return *m_face < *fm.m_face; } // return identity of the face

  bool
  operator< (const Ptr<Face> &face) const { return *m_face < *face; }

  Ptr<Face>
  GetFace () const { return m_face; }

  void
  UpdateRtt (const Time &rttSample);

  Status
  GetStatus () const
  {
    return m_status;
  }

  void
  SetStatus (Status status)
  {
    m_status.Set (status);
  }

  int32_t
  GetRoutingCost () const
  {
    return m_routingCost;
  }

  void
  SetRoutingCost (int32_t routingCost)
  {
    m_routingCost = routingCost;
  }

  Time
  GetSRtt () const
  {
    return m_sRtt;
  }

  Time
  GetRttVar () const
  {
    return m_rttVar;
  }
  
  Time
  GetRealDelay () const
  {
    return m_realDelay;
  }

  void
  SetRealDelay (Time realDelay)
  {
    m_realDelay = realDelay;
  }

  TracedValue<Status> &
  GetStatusTrace ()
  {
    return m_status;
  }

private:
  friend std::ostream& operator<< (std::ostream& os, const FaceMetric &metric);

private:
  Ptr<Face> m_face; 

  TracedValue<Status> m_status; 

  int32_t m_routingCost; 

  Time m_sRtt;         
  Time m_rttVar;       

  Time m_realDelay;    
};

class i_face {};
class i_metric {};
class i_nth {};


struct FaceMetricContainer
{
  typedef boost::multi_index::multi_index_container<
    FaceMetric,
    boost::multi_index::indexed_by<
      // For fast access to elements using Face
      boost::multi_index::ordered_unique<
        boost::multi_index::tag<i_face>,
        boost::multi_index::const_mem_fun<FaceMetric,Ptr<Face>,&FaceMetric::GetFace>
      >,

      // List of available faces ordered by (status, m_routingCost)
      boost::multi_index::ordered_non_unique<
        boost::multi_index::tag<i_metric>,
        boost::multi_index::composite_key<
          FaceMetric,
          boost::multi_index::const_mem_fun<FaceMetric,FaceMetric::Status,&FaceMetric::GetStatus>,
          boost::multi_index::const_mem_fun<FaceMetric,int32_t,&FaceMetric::GetRoutingCost>
        >
      >,

      // To optimize nth candidate selection (sacrifice a little bit space to gain speed)
      boost::multi_index::random_access<
        boost::multi_index::tag<i_nth>
      >
    >
   > type;
};

class Entry : public Object
{
public:
  typedef Entry base_type;

public:
  class NoFaces {}; 

  Entry (Ptr<Fib> fib, const Ptr<const Name> &prefix)
  : m_fib (fib)
  , m_prefix (prefix)
  , m_needsProbing (false)
  {
  }

  void UpdateStatus (Ptr<Face> face, FaceMetric::Status status);

  void AddOrUpdateRoutingMetric (Ptr<Face> face, int32_t metric);

  void
  SetRealDelayToProducer (Ptr<Face> face, Time delay);

  void
  Invalidate ();

  void
  UpdateFaceRtt (Ptr<Face> face, const Time &sample);

  const Name&
  GetPrefix () const { return *m_prefix; }

  const FaceMetric &
  FindBestCandidate (uint32_t skip = 0) const;

  void
  RemoveFace (const Ptr<Face> &face)
  {
    m_faces.erase (face);
  }

  Ptr<Fib>
  GetFib ();
  
private:
  friend std::ostream& operator<< (std::ostream& os, const Entry &entry);

public:
  Ptr<Fib> m_fib; 

  Ptr<const Name> m_prefix; 
  FaceMetricContainer::type m_faces; 

  bool m_needsProbing;      
};

std::ostream& operator<< (std::ostream& os, const Entry &entry);
std::ostream& operator<< (std::ostream& os, const FaceMetric &metric);

} // namespace fib
} // namespace ndn
} // namespace ns3

#endif // _NDN_FIB_ENTRY_H_