/*****************************************************************************Copyright (c) 2001 - 2008, The Board of Trustees of the University of Illinois.All rights reserved.Redistribution and use in source and binary forms, with or withoutmodification, are permitted provided that the following conditions aremet:* Redistributions of source code must retain the above  copyright notice, this list of conditions and the  following disclaimer.* Redistributions in binary form must reproduce the  above copyright notice, this list of conditions  and the following disclaimer in the documentation  and/or other materials provided with the distribution.* Neither the name of the University of Illinois  nor the names of its contributors may be used to  endorse or promote products derived from this  software without specific prior written permission.THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "ASIS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULARPURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER ORCONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, ORPROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OFLIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDINGNEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THISSOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.*****************************************************************************//*****************************************************************************written by   Yunhong Gu, last updated 12/06/2008*****************************************************************************/#include <cmath>#include "common.h"#include "window.h"CACKWindow::CACKWindow():m_piACKSeqNo(NULL),m_piACK(NULL),m_pTimeStamp(NULL),m_iSize(1024),m_iHead(0),m_iTail(0){   m_piACKSeqNo = new int32_t[m_iSize];   m_piACK = new int32_t[m_iSize];   m_pTimeStamp = new uint64_t[m_iSize];   m_piACKSeqNo[0] = -1;}CACKWindow::CACKWindow(const int& size):m_piACKSeqNo(NULL),m_piACK(NULL),m_pTimeStamp(NULL),m_iSize(size),m_iHead(0),m_iTail(0){   m_piACKSeqNo = new int32_t[m_iSize];   m_piACK = new int32_t[m_iSize];   m_pTimeStamp = new uint64_t[m_iSize];   m_piACKSeqNo[0] = -1;}CACKWindow::~CACKWindow(){   delete [] m_piACKSeqNo;   delete [] m_piACK;   delete [] m_pTimeStamp;}void CACKWindow::store(const int32_t& seq, const int32_t& ack){   m_piACKSeqNo[m_iHead] = seq;   m_piACK[m_iHead] = ack;   m_pTimeStamp[m_iHead] = CTimer::getTime();   m_iHead = (m_iHead + 1) % m_iSize;   // overwrite the oldest ACK since it is not likely to be acknowledged   if (m_iHead == m_iTail)      m_iTail = (m_iTail + 1) % m_iSize;}int CACKWindow::acknowledge(const int32_t& seq, int32_t& ack){   if (m_iHead >= m_iTail)   {      // Head has not exceeded the physical boundary of the window      for (int i = m_iTail, n = m_iHead; i < n; ++ i)         // looking for indentical ACK Seq. No.         if (seq == m_piACKSeqNo[i])         {            // return the Data ACK it carried            ack = m_piACK[i];            // calculate RTT            int rtt = int(CTimer::getTime() - m_pTimeStamp[i]);            if (i + 1 == m_iHead)            {               m_iTail = m_iHead = 0;               m_piACKSeqNo[0] = -1;            }            else               m_iTail = (i + 1) % m_iSize;            return rtt;         }      // Bad input, the ACK node has been overwritten      return -1;   }   // Head has exceeded the physical window boundary, so it is behind tail   for (int j = m_iTail, n = m_iHead + m_iSize; j < n; ++ j)      // looking for indentical ACK seq. no.      if (seq == m_piACKSeqNo[j % m_iSize])      {         // return Data ACK         j %= m_iSize;         ack = m_piACK[j];         // calculate RTT         int rtt = int(CTimer::getTime() - m_pTimeStamp[j]);         if (j == m_iHead)         {            m_iTail = m_iHead = 0;            m_piACKSeqNo[0] = -1;         }         else            m_iTail = (j + 1) % m_iSize;         return rtt;      }   // bad input, the ACK node has been overwritten   return -1;}////////////////////////////////////////////////////////////////////////////////CPktTimeWindow::CPktTimeWindow():m_iAWSize(16),m_piPktWindow(NULL),m_iPWSize(16),m_piProbeWindow(NULL){   m_piPktWindow = new int[m_iAWSize];   m_piProbeWindow = new int[m_iPWSize];   m_iPktWindowPtr = 0;   m_iProbeWindowPtr = 0;   m_LastArrTime = CTimer::getTime();   m_iLastSentTime = 0;   m_iMinPktSndInt = 1000000;   for (int i = 0; i < m_iAWSize; ++ i)      m_piPktWindow[i] = 1;   for (int k = 0; k < m_iPWSize; ++ k)      m_piProbeWindow[k] = 1000;}CPktTimeWindow::CPktTimeWindow(const int& asize, const int& psize):m_iAWSize(asize),m_piPktWindow(NULL),m_iPWSize(psize),m_piProbeWindow(NULL){   m_piPktWindow = new int[m_iAWSize];   m_piProbeWindow = new int[m_iPWSize];   m_iPktWindowPtr = 0;   m_iProbeWindowPtr = 0;   m_LastArrTime = CTimer::getTime();   m_iLastSentTime = 0;   m_iMinPktSndInt = 1000000;   for (int i = 0; i < m_iAWSize; ++ i)      m_piPktWindow[i] = 1;   for (int k = 0; k < m_iPWSize; ++ k)      m_piProbeWindow[k] = 1000;}CPktTimeWindow::~CPktTimeWindow(){   delete [] m_piPktWindow;   delete [] m_piProbeWindow;}int CPktTimeWindow::getMinPktSndInt() const{   return m_iMinPktSndInt;}int CPktTimeWindow::getPktRcvSpeed() const{   // sorting   int* pi = m_piPktWindow;   for (int i = 0, n = (m_iAWSize >> 1) + 1; i < n; ++ i)   {      int* pj = pi;      for (int j = i, m = m_iAWSize; j < m; ++ j)      {         if (*pi > *pj)         {            int temp = *pi;            *pi = *pj;            *pj = temp;         }         ++ pj;      }      ++ pi;   }   // read the median value   int median = (m_piPktWindow[(m_iAWSize >> 1) - 1] + m_piPktWindow[m_iAWSize >> 1]) >> 1;   int count = 0;   int sum = 0;   int upper = median << 3;   int lower = median >> 3;   // median filtering   int* pk = m_piPktWindow;   for (int k = 0, l = m_iAWSize; k < l; ++ k)   {      if ((*pk < upper) && (*pk > lower))      {         ++ count;         sum += *pk;      }      ++ pk;   }   // claculate speed, or return 0 if not enough valid value   if (count > (m_iAWSize >> 1))      return (int)ceil(1000000.0 / (sum / count));   else      return 0;}int CPktTimeWindow::getBandwidth() const{   // sorting   int* pi = m_piProbeWindow;   for (int i = 0, n = (m_iPWSize >> 1) + 1; i < n; ++ i)   {      int* pj = pi;      for (int j = i, m = m_iPWSize; j < m; ++ j)      {         if (*pi > *pj)         {            int temp = *pi;            *pi = *pj;            *pj = temp;         }         ++ pj;      }      ++ pi;   }   // read the median value   int median = (m_piProbeWindow[(m_iPWSize >> 1) - 1] + m_piProbeWindow[m_iPWSize >> 1]) >> 1;   int count = 1;   int sum = median;   int upper = median << 3;   int lower = median >> 3;   // median filtering   int* pk = m_piProbeWindow;   for (int k = 0, l = m_iPWSize; k < l; ++ k)   {      if ((*pk < upper) && (*pk > lower))      {         ++ count;         sum += *pk;      }      ++ pk;   }   return (int)ceil(1000000.0 / (double(sum) / double(count)));}void CPktTimeWindow::onPktSent(const int& currtime){   int interval = currtime - m_iLastSentTime;   if ((interval < m_iMinPktSndInt) && (interval > 0))      m_iMinPktSndInt = interval;   m_iLastSentTime = currtime;}void CPktTimeWindow::onPktArrival(){   m_CurrArrTime = CTimer::getTime();   // record the packet interval between the current and the last one   *(m_piPktWindow + m_iPktWindowPtr) = int(m_CurrArrTime - m_LastArrTime);   // the window is logically circular   ++ m_iPktWindowPtr;   if (m_iPktWindowPtr == m_iAWSize)      m_iPktWindowPtr = 0;   // remember last packet arrival time   m_LastArrTime = m_CurrArrTime;}void CPktTimeWindow::probe1Arrival(){   m_ProbeTime = CTimer::getTime();}void CPktTimeWindow::probe2Arrival(){   m_CurrArrTime = CTimer::getTime();   // record the probing packets interval   *(m_piProbeWindow + m_iProbeWindowPtr) = int(m_CurrArrTime - m_ProbeTime);   // the window is logically circular   ++ m_iProbeWindowPtr;   if (m_iProbeWindowPtr == m_iPWSize)      m_iProbeWindowPtr = 0;}