SECTOR Code

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/*****************************************************************************
written by
   Yunhong Gu, last updated 09/17/2009
*****************************************************************************/

#ifndef WIN32
   #include <sys/time.h>
   #include <time.h>
#else
   #include <windows.h>
#endif

#include <common.h>
#include <dhash.h>
#include <prec.h>

using namespace std;

CPeerManagement::CPeerManagement()
{
   #ifndef WIN32
      pthread_mutex_init(&m_PeerRecLock, NULL);
   #else
      m_PeerRecLock = CreateMutex(NULL, false, NULL);
   #endif

   int n = 1 << m_uiHashSpace;
   m_pllHashRec = new int64_t [n];
   for (int i = 0; i < n; ++ i)
      m_pllHashRec[i] = -1000001;
}

CPeerManagement::~CPeerManagement()
{
   #ifndef WIN32
      pthread_mutex_destroy(&m_PeerRecLock);
   #else
      CloseHandle(m_PeerRecLock);
   #endif

   delete [] m_pllHashRec;
}

void CPeerManagement::insert(const string& ip, const int& port, const int& session, const int32_t& id, const int& rtt, const int& fw)
{
   CGuard recguard(m_PeerRecLock);

   if (rtt > 0)
   {
      map<string, int>::iterator t = m_mRTT.find(ip);
      if (t != m_mRTT.end())
         t->second = (t->second * 7 + rtt) >> 3;
      else
         m_mRTT[ip] = rtt;
   }

   int key = hash(ip, port, session, id);
   m_pllHashRec[key] = CTimer::getTime();

   CPeerRecord* pr = new CPeerRecord;
   pr->m_strIP = ip;
   pr->m_iPort = port;
   pr->m_iSession = session;

   set<CPeerRecord*, CFPeerRec>::iterator i = m_sPeerRec.find(pr);
   map<string, int>::iterator t = m_mRTT.find(ip);

   if (i != m_sPeerRec.end())
   {
      if (id > (*i)->m_iID)
         (*i)->m_iID = id;
      (*i)->m_iFlowWindow = fw;

      m_sPeerRecByTS.erase(*i);
      (*i)->m_llTimeStamp = CTimer::getTime();
      m_sPeerRecByTS.insert(*i);

      delete pr;
   }
   else
   {
      if (id > 0)
         pr->m_iID = id;
      else
         pr->m_iID = -1;

      pr->m_llTimeStamp = CTimer::getTime();
      pr->m_iFlowWindow = fw;

      m_sPeerRec.insert(pr);
      m_sPeerRecByTS.insert(pr);

      if (m_sPeerRecByTS.size() > m_uiRecLimit)
      {
         // delete first one
         set<CPeerRecord*, CFPeerRecByTS>::iterator j = m_sPeerRecByTS.begin();

         CPeerRecord* t = *j;
         m_sPeerRec.erase(t);
         m_sPeerRecByTS.erase(j);

         bool delip = true;
         for (set<CPeerRecord*, CFPeerRec>::iterator k = m_sPeerRec.begin(); k != m_sPeerRec.end(); ++ k)
         {
            if ((*k)->m_strIP == t->m_strIP)
            {
               delip = false;
               break;
            }
         }

         if (delip)
            m_mRTT.erase(t->m_strIP);

         delete t;
      }
   }
}

int CPeerManagement::getRTT(const string& ip)
{
   CGuard recguard(m_PeerRecLock);

   map<string, int>::iterator t = m_mRTT.find(ip);
   if (t != m_mRTT.end())
      return t->second;

   return -1;
}

int CPeerManagement::getLastID(const string& ip, const int& port, const int& session)
{
   CPeerRecord pr;
   pr.m_strIP = ip;
   pr.m_iPort = port;
   pr.m_iSession = session;

   CGuard recguard(m_PeerRecLock);

   set<CPeerRecord*, CFPeerRec>::iterator i = m_sPeerRec.find(&pr);
   if (i != m_sPeerRec.end())
      return (*i)->m_iID;

   return -1;
}

void CPeerManagement::clearRTT(const string& ip)
{
   CGuard recguard(m_PeerRecLock);
   m_mRTT.erase(ip);
}

int CPeerManagement::flowControl(const std::string& ip, const int& port, const int& session)
{
   CPeerRecord pr;
   pr.m_strIP = ip;
   pr.m_iPort = port;
   pr.m_iSession = session;

   CGuard recguard(m_PeerRecLock);

   set<CPeerRecord*, CFPeerRec>::iterator i = m_sPeerRec.find(&pr);
   if (i == m_sPeerRec.end())
      return 0;

   int thresh = (*i)->m_iFlowWindow - (CTimer::getTime() - (*i)->m_llTimeStamp) / 1000;

   if (thresh > 100)
   {
      usleep(100000);
      return 100000;
   }

   if (thresh > 10)
   {
      usleep(10000);
      return 10000;
   }

   return 0;
}

int32_t CPeerManagement::hash(const string& ip, const int& port, const int& session, const int32_t& id)
{
   char tmp[1024];
   sprintf(tmp, "%s%d%d%d", ip.c_str(), port, session, id);

   return DHash::hash(tmp, m_uiHashSpace);
}

bool CPeerManagement::hit(const string& ip, const int& port, const int& session, const int32_t& id)
{
   int key = hash(ip, port, session, id);
   int64_t diff = CTimer::getTime() - m_pllHashRec[key];

   if ((diff > 1000000) || (diff < 0))
      return false;

   return true;
}