#include <TCPSACKRexmitQueue.h>

Classes
struct	Region
Public Types
typedef std::list< Region >	RexmitQueue
Public Member Functions
	TCPSACKRexmitQueue ()
virtual	~TCPSACKRexmitQueue ()
virtual void	setConnection (TCPConnection *_conn)
virtual void	init (uint32 seqNum)
virtual std::string	str () const
virtual void	info ()
virtual uint32	getBufferStartSeq ()
virtual uint32	getBufferEndSeq ()
virtual void	discardUpTo (uint32 seqNum)
virtual void	enqueueSentData (uint32 fromSeqNum, uint32 toSeqNum)
virtual void	setSackedBit (uint32 fromSeqNum, uint32 toSeqNum)
virtual bool	getSackedBit (uint32 seqNum)
virtual uint32	getQueueLength ()
virtual uint32	getHighestSackedSeqNum ()
virtual uint32	getHighestRexmittedSeqNum ()
virtual uint32	checkRexmitQueueForSackedOrRexmittedSegments (uint32 fromSeq)
virtual void	resetSackedBit ()
virtual void	resetRexmittedBit ()
virtual uint32	getTotalAmountOfSackedBytes ()
virtual uint32	getAmountOfSackedBytes (uint32 seqNum)
virtual uint32	getNumOfDiscontiguousSacks (uint32 seqNum)
Public Attributes
TCPConnection *	conn
RexmitQueue	rexmitQueue
uint32	begin
uint32	end

Detailed Description

Retransmission data for SACK.

Definition at line 29 of file TCPSACKRexmitQueue.h.

Member Typedef Documentation

typedef std::list<Region> TCPSACKRexmitQueue::RexmitQueue

Definition at line 41 of file TCPSACKRexmitQueue.h.

Constructor & Destructor Documentation

TCPSACKRexmitQueue::TCPSACKRexmitQueue ( )

Ctor

Definition at line 22 of file TCPSACKRexmitQueue.cc.

{
    conn = NULL;
    begin = end = 0;
}

TCPSACKRexmitQueue::~TCPSACKRexmitQueue ( ) [virtual]

Virtual dtor.

Definition at line 28 of file TCPSACKRexmitQueue.cc.

{
    while (!rexmitQueue.empty())
        rexmitQueue.pop_front();
}

Member Function Documentation

uint32 TCPSACKRexmitQueue::checkRexmitQueueForSackedOrRexmittedSegments ( uint32 fromSeq ) [virtual]

Checks rexmit queue for sacked of rexmitted segments and returns a certain offset (contiguous sacked or rexmitted region) to forward snd->nxt. It is called before retransmitting data.

Definition at line 225 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::sendSegment().

{
    uint32 counter = 0;

    if (fromSeqNum==0 || rexmitQueue.empty() || !(seqLE(begin,fromSeqNum) && seqLE(fromSeqNum,end)))
        return counter;

    RexmitQueue::iterator i = rexmitQueue.begin();
    while (i!=rexmitQueue.end())
    {
        // search for fromSeqNum (snd_nxt)
        if (i->beginSeqNum == fromSeqNum)
            break;
        else
            i++;
    }

    // search for adjacent sacked/rexmitted regions
    while (i!=rexmitQueue.end())
    {
        if (i->sacked || i->rexmitted)
        {
            counter = counter + (i->endSeqNum - i->beginSeqNum);

            // adjacent regions?
            uint32 tmp = i->endSeqNum;
            i++;
            if (i->beginSeqNum != tmp)
                break;
        }
        else
            break;
    }
    return counter;
}

void TCPSACKRexmitQueue::discardUpTo ( uint32 seqNum ) [virtual]

Tells the queue that bytes up to (but NOT including) seqNum have been transmitted and ACKed, so they can be removed from the queue.

Definition at line 70 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::processAckInEstabEtc(), TCPConnection::processRstInSynReceived(), and TCPConnection::processSegmentInSynSent().

{
    if (rexmitQueue.empty())
        return;

    ASSERT(seqLE(begin,seqNum) && seqLE(seqNum,end));
    begin = seqNum;

    RexmitQueue::iterator i = rexmitQueue.begin();
    while (i!=rexmitQueue.end()) // discard/delete regions from rexmit queue, which have been acked
    {
        if (seqLess(i->beginSeqNum,begin))
            i = rexmitQueue.erase(i);
        else
            i++;
    }

    // update begin and end of rexmit queue
    if (rexmitQueue.empty())
        begin = end = 0;
    else
    {
        i = rexmitQueue.begin();
        begin = i->beginSeqNum;
        i = rexmitQueue.end();
        end = i->endSeqNum;
    }
}

void TCPSACKRexmitQueue::enqueueSentData	(	uint32	fromSeqNum,
		uint32	toSeqNum
	)			`[virtual]`

Inserts sent data to the rexmit queue.

Definition at line 99 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::sendSegment().

{
    bool found = false;

    tcpEV << "rexmitQ: " << str() << " enqueueSentData [" << fromSeqNum << ".." << toSeqNum << ")\n";

    Region region;
    region.beginSeqNum = fromSeqNum;
    region.endSeqNum = toSeqNum;
    region.sacked = false;
    region.rexmitted = false;

    if (getQueueLength()==0)
    {
        begin = fromSeqNum;
        end = toSeqNum;
        rexmitQueue.push_back(region);
//        tcpEV << "rexmitQ: rexmitQLength=" << getQueueLength() << "\n";
        return;
    }

    if (seqLE(begin,fromSeqNum) && seqLE(toSeqNum,end))
    {
        // Search for region in queue!
        RexmitQueue::iterator i = rexmitQueue.begin();
        while (i!=rexmitQueue.end())
        {
            if (i->beginSeqNum == fromSeqNum && i->endSeqNum == toSeqNum)
            {
                i->rexmitted = true; // set rexmitted bit
                found = true;
            }
            i++;
        }
    }

    if (!found)
    {
        end = toSeqNum;
        rexmitQueue.push_back(region);
    }
//    tcpEV << "rexmitQ: rexmitQLength=" << getQueueLength() << "\n";
}

uint32 TCPSACKRexmitQueue::getAmountOfSackedBytes ( uint32 seqNum ) [virtual]

Returns amount of sacked bytes above seqNum.

Definition at line 299 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::isLost().

{
    uint32 bytes = 0;
    uint32 counter = 0;

    if (rexmitQueue.empty() || seqGE(seqNum,end))
        return counter;

    RexmitQueue::iterator i = rexmitQueue.begin();
    while (i!=rexmitQueue.end() && seqLess(i->beginSeqNum, seqNum)) // search for seqNum
    {
        i++;
        if (i->beginSeqNum == seqNum)
            break;
    }

    ASSERT(seqLE(seqNum,i->beginSeqNum) || seqGE(seqNum,--i->endSeqNum));

    while (i!=rexmitQueue.end())
    {
        if (i->sacked)
        {
            counter++;
            bytes = bytes + (i->endSeqNum - i->beginSeqNum);
        }
        i++;
    }
    return bytes;
}

uint32 TCPSACKRexmitQueue::getBufferEndSeq ( ) [virtual]

Returns the sequence number of the last byte stored in the buffer plus one. (The first byte of the next send operation would get this sequence number.)

Definition at line 65 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::processRstInSynReceived().

{
    return end;
}

uint32 TCPSACKRexmitQueue::getBufferStartSeq ( ) [virtual]

Returns the sequence number of the first byte stored in the buffer.

Definition at line 60 of file TCPSACKRexmitQueue.cc.

{
    return begin;
}

uint32 TCPSACKRexmitQueue::getHighestRexmittedSeqNum ( ) [virtual]

Returns the highest sequence number rexmitted by data sender.

Definition at line 211 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::nextSeg(), TCPConnection::retransmitOneSegment(), TCPConnection::sendData(), TCPConnection::sendSegmentDuringLossRecoveryPhase(), and TCPConnection::setPipe().

{
    uint32 tmp_highest_rexmitted = 0;

    RexmitQueue::iterator i = rexmitQueue.begin();
    while (i!=rexmitQueue.end())
    {
        if (i->rexmitted)
            tmp_highest_rexmitted = i->endSeqNum;
        i++;
    }
    return tmp_highest_rexmitted;
}

uint32 TCPSACKRexmitQueue::getHighestSackedSeqNum ( ) [virtual]

Returns the highest sequence number sacked by data receiver.

Definition at line 197 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::nextSeg().

{
    uint32 tmp_highest_sacked = 0;

    RexmitQueue::iterator i = rexmitQueue.begin();
    while (i!=rexmitQueue.end())
    {
        if (i->sacked)
            tmp_highest_sacked = i->endSeqNum;
        i++;
    }
    return tmp_highest_sacked;
}

uint32 TCPSACKRexmitQueue::getNumOfDiscontiguousSacks ( uint32 seqNum ) [virtual]

Returns the number of discontiguous sacked regions (SACKed sequences) above seqNum.

Definition at line 330 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::isLost().

{
    uint32 counter = 0;

    if (rexmitQueue.empty() || seqGE(seqNum,end))
        return counter;

    RexmitQueue::iterator i = rexmitQueue.begin();
    while (i!=rexmitQueue.end() && seqLess(i->beginSeqNum, seqNum)) // search for seqNum
    {
        i++;
        if (i->beginSeqNum == seqNum)
            break;
    }

    ASSERT(seqLE(seqNum,i->beginSeqNum) || seqGE(seqNum,--i->endSeqNum));

    // search for discontiguous sacked regions
    while (i!=rexmitQueue.end())
    {
        if (i->sacked)
        {
            counter++;
            uint32 tmp = i->endSeqNum;
            i++;
            while (i->sacked && i->beginSeqNum == tmp && i!=rexmitQueue.end()) // adjacent sacked regions?
            {
                tmp = i->endSeqNum;
                i++;
            }
        }
        else
            i++;
    }
    return counter;
}

uint32 TCPSACKRexmitQueue::getQueueLength ( ) [virtual]

Returns the number of blocks currently buffered in queue.

Definition at line 192 of file TCPSACKRexmitQueue.cc.

Referenced by enqueueSentData().

{
    return rexmitQueue.size();
}

bool TCPSACKRexmitQueue::getSackedBit ( uint32 seqNum ) [virtual]

Returns SackedBit value of seqNum.

Definition at line 172 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::nextSeg(), and TCPConnection::setPipe().

{
    bool found = false;

    if (seqLE(begin,seqNum))
    {
        RexmitQueue::iterator i = rexmitQueue.begin();
        while (i!=rexmitQueue.end())
        {
            if (i->beginSeqNum == seqNum) // Search for region in queue!
            {
                found = i->sacked;
                break;
            }
            i++;
        }
    }
    return found;
}

uint32 TCPSACKRexmitQueue::getTotalAmountOfSackedBytes ( ) [virtual]

Returns total amount of sacked bytes. Corresponds to update() function from RFC 3517.

Definition at line 281 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::processSACKOption().

{
    uint32 bytes = 0;
    uint32 counter = 0;

    RexmitQueue::iterator i = rexmitQueue.begin();
    while (i!=rexmitQueue.end())
    {
        if (i->sacked)
        {
            counter++;
            bytes = bytes + (i->endSeqNum - i->beginSeqNum);
        }
        i++;
    }
    return bytes;
}

void TCPSACKRexmitQueue::info ( ) [virtual]

Prints the current rexmitQueue status for debug purposes.

Definition at line 47 of file TCPSACKRexmitQueue.cc.

{
    str();
    RexmitQueue::iterator i = rexmitQueue.begin();
    uint j = 1;
    while (i!=rexmitQueue.end())
    {
        tcpEV << j << ". region: [" << i->beginSeqNum << ".." << i->endSeqNum << ") \t sacked=" << i->sacked << "\t rexmitted=" << i->rexmitted << "\n";
        i++;
        j++;
    }
}

void TCPSACKRexmitQueue::init ( uint32 seqNum ) [virtual]

Initialize the object. The startSeq parameter tells what sequence number the first byte of app data should get. This is usually ISS+1 because SYN consumes one byte in the sequence number space.

init() may be called more than once; every call flushes the existing contents of the queue.

Definition at line 34 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::selectInitialSeqNum().

{
    begin = seqNum;
    end = seqNum;
}

void TCPSACKRexmitQueue::resetRexmittedBit ( ) [virtual]

Called when REXMIT timer expired. Resets rexmitted bit of all segments in rexmit queue.

Definition at line 271 of file TCPSACKRexmitQueue.cc.

Referenced by TCPBaseAlg::processRexmitTimer().

{
    RexmitQueue::iterator i = rexmitQueue.begin();
    while (i!=rexmitQueue.end())
    {
        i->rexmitted = false; // reset rexmitted bit
        i++;
    }
}

void TCPSACKRexmitQueue::resetSackedBit ( ) [virtual]

Called when REXMIT timer expired. Resets sacked bit of all segments in rexmit queue.

Definition at line 261 of file TCPSACKRexmitQueue.cc.

Referenced by TCPBaseAlg::processRexmitTimer().

{
    RexmitQueue::iterator i = rexmitQueue.begin();
    while (i!=rexmitQueue.end())
    {
        i->sacked = false; // reset sacked bit
        i++;
    }
}

virtual void TCPSACKRexmitQueue::setConnection ( TCPConnection * _conn ) [inline, virtual]

Set the connection that owns this queue.

Definition at line 61 of file TCPSACKRexmitQueue.h.

Referenced by TCPConnection::cloneListeningConnection(), and TCPConnection::initConnection().

{conn = _conn;}

void TCPSACKRexmitQueue::setSackedBit	(	uint32	fromSeqNum,
		uint32	toSeqNum
	)			`[virtual]`

Called when data sender received selective acknowledgments. Tells the queue which bytes have been transmitted and SACKed, so they can be skipped if retransmitting segments as long as REXMIT timer did not expired.

Definition at line 143 of file TCPSACKRexmitQueue.cc.

Referenced by TCPConnection::processSACKOption().

{
    bool found = false;

    if (seqLE(toSeqNum,end))
    {
        RexmitQueue::iterator i = rexmitQueue.begin();
        while (i!=rexmitQueue.end())
        {
            if (i->beginSeqNum == fromSeqNum && seqGE(toSeqNum, i->endSeqNum)) // Search for LE of region in queue!
            {
                i->sacked = true; // set sacked bit
                found = true;
                i++;
                while (seqGE(toSeqNum, i->endSeqNum) && i!=rexmitQueue.end()) // Search for RE of region in queue!
                {
                    i->sacked = true; // set sacked bit
                    i++;
                }
            }
            else
                i++;
        }
    }

    if (!found)
        tcpEV << "FAILED to set sacked bit for region: [" << fromSeqNum << ".." << toSeqNum << "). Not found in retransmission queue.\n";
}

std::string TCPSACKRexmitQueue::str ( ) const [virtual]

Returns a string for debug purposes.

Definition at line 40 of file TCPSACKRexmitQueue.cc.

Referenced by enqueueSentData(), and info().

{
    std::stringstream out;
    out << "[" << begin << ".." << end << ")";
    return out.str();
}

Member Data Documentation

uint32 TCPSACKRexmitQueue::begin

Definition at line 44 of file TCPSACKRexmitQueue.h.

Referenced by checkRexmitQueueForSackedOrRexmittedSegments(), discardUpTo(), enqueueSentData(), getBufferStartSeq(), getSackedBit(), init(), str(), and TCPSACKRexmitQueue().

TCPConnection* TCPSACKRexmitQueue::conn

Definition at line 32 of file TCPSACKRexmitQueue.h.

Referenced by TCPSACKRexmitQueue().

uint32 TCPSACKRexmitQueue::end

Definition at line 45 of file TCPSACKRexmitQueue.h.

Referenced by checkRexmitQueueForSackedOrRexmittedSegments(), discardUpTo(), enqueueSentData(), getAmountOfSackedBytes(), getBufferEndSeq(), getNumOfDiscontiguousSacks(), init(), setSackedBit(), str(), and TCPSACKRexmitQueue().

RexmitQueue TCPSACKRexmitQueue::rexmitQueue

Definition at line 42 of file TCPSACKRexmitQueue.h.

Referenced by checkRexmitQueueForSackedOrRexmittedSegments(), discardUpTo(), enqueueSentData(), getAmountOfSackedBytes(), getHighestRexmittedSeqNum(), getHighestSackedSeqNum(), getNumOfDiscontiguousSacks(), getQueueLength(), getSackedBit(), getTotalAmountOfSackedBytes(), info(), resetRexmittedBit(), resetSackedBit(), setSackedBit(), and ~TCPSACKRexmitQueue().

The documentation for this class was generated from the following files:

TCPSACKRexmitQueue Class Reference

Classes

Public Types

Public Member Functions

Public Attributes

Detailed Description

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation