/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

/*

 * Copyright (c) 2013 Universita' di Firenze

 *

 * 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: Tommaso Pecorella <tommaso.pecorella@unifi.it>

 */

#include "ipv6-pmtu-cache.h"

#include "ns3/log.h"

NS_LOG_COMPONENT_DEFINE ("Ipv6PmtuCache");

namespace ns3 {

NS_OBJECT_ENSURE_REGISTERED (Ipv6PmtuCache);

TypeId Ipv6PmtuCache::GetTypeId ()

{

  static TypeId tid = TypeId ("ns3::Ipv6PmtuCache")

    .SetParent<Object> ()

    .AddAttribute ("CacheExpiryTime",

                   "Validity time for a Path MTU entry. Default is 10 minutes, minimum is 5 minutes.",

                   TimeValue (Seconds (60 * 10)),

                   MakeTimeAccessor (&Ipv6PmtuCache::m_validityTime),

                   MakeTimeChecker (Time (Seconds (60 * 5))))

  ;

  return tid;

}

Ipv6PmtuCache::Ipv6PmtuCache ()

{

}

Ipv6PmtuCache::~Ipv6PmtuCache ()

{

}

void Ipv6PmtuCache::DoDispose ()

{

  for (pathMtuTimerIter iter = m_pathMtuTimer.begin (); iter != m_pathMtuTimer.end (); iter++)

    {

      iter->second.Cancel ();

    }

  m_pathMtuTimer.clear ();

  m_pathMtu.clear ();

}

uint32_t Ipv6PmtuCache::GetPmtu (Ipv6Address dst)

{

  NS_LOG_FUNCTION (this << dst);

  if (m_pathMtu.find (dst) != m_pathMtu.end ())

    {

      return m_pathMtu[dst];

    }

  return 0;

}

void Ipv6PmtuCache::SetPmtu (Ipv6Address dst, uint32_t pmtu)

{

  NS_LOG_FUNCTION (this << dst << pmtu);

  m_pathMtu[dst] = pmtu;

  if (m_pathMtuTimer.find (dst) != m_pathMtuTimer.end ())

    {

      m_pathMtuTimer[dst].Cancel ();

    }

  EventId pMtuTimer;

  pMtuTimer = Simulator::Schedule (m_validityTime, &Ipv6PmtuCache::ClearPmtu, this, dst);

  m_pathMtuTimer[dst] = pMtuTimer;

}

Time Ipv6PmtuCache::GetPmtuValidityTime () const

{

  NS_LOG_FUNCTION (this);

  return m_validityTime;

}

bool Ipv6PmtuCache::SetPmtuValidityTime (Time validity)

{

  NS_LOG_FUNCTION (this << validity);

  if (validity > Seconds (60 * 5))

    {

      m_validityTime = validity;

      return true;

    }

  NS_LOG_LOGIC ("rejecting a PMTU validity timer lesser than 5 minutes");

  return false;

}

void Ipv6PmtuCache::ClearPmtu (Ipv6Address dst)

{

  NS_LOG_FUNCTION (this << dst);

  m_pathMtu.erase (dst);

  m_pathMtuTimer.erase (dst);

}

}