inet::tcp::TcpSendQueue Class Reference

Send queue that manages Chunks. More...

#include <TcpSendQueue.h>

Inheritance diagram for inet::tcp::TcpSendQueue:

Public Member Functions
	TcpSendQueue ()
	Ctor. More...
virtual	~TcpSendQueue ()
	Virtual dtor. More...
virtual ChunkQueue &	getDataBuffer ()
virtual void	setConnection (TcpConnection *_conn)
	Set the connection that owns this queue. More...
virtual void	init (uint32_t startSeq)
	Initialize the object. More...
virtual std::string	str () const override
	Returns a string with the region stored. More...
virtual void	enqueueAppData (Packet *msg)
	Called on SEND app command, it inserts in the queue the data the user wants to send. More...
virtual uint32_t	getBufferStartSeq () const
	Returns the sequence number of the first byte stored in the buffer. More...
virtual uint32_t	getBufferEndSeq () const
	Returns the sequence number of the last byte stored in the buffer plus one. More...
virtual uint32_t	getBytesAvailable (uint32_t fromSeq) const
	Utility function: returns how many bytes are available in the queue, from (and including) the given sequence number. More...
virtual Packet *	createSegmentWithBytes (uint32_t fromSeq, uint32_t numBytes)
	Called when the TCP wants to send or retransmit data, it constructs a TCP segment which contains the data from the requested sequence number range. More...
virtual void	discardUpTo (uint32_t seqNum)
	Tells the queue that bytes up to (but NOT including) seqNum have been transmitted and ACKed, so they can be removed from the queue. More...

Protected Attributes
TcpConnection *	conn = nullptr
uint32_t	begin = 0
uint32_t	end = 0
ChunkQueue	dataBuffer

Detailed Description

Send queue that manages Chunks.

See also

TCPRcvQueue

Constructor & Destructor Documentation

TcpSendQueue()

inet::tcp::TcpSendQueue::TcpSendQueue

(

)

Ctor.

{
}

~TcpSendQueue()

inet::tcp::TcpSendQueue::~TcpSendQueue ( )

virtual

Virtual dtor.

{
}

Member Function Documentation

createSegmentWithBytes()

Packet * inet::tcp::TcpSendQueue::createSegmentWithBytes ( uint32_t  fromSeq, uint32_t  numBytes  )

virtual

Called when the TCP wants to send or retransmit data, it constructs a TCP segment which contains the data from the requested sequence number range.

The actually returned segment may contain less than maxNumBytes bytes if the subclass wants to reproduce the original segment boundaries when retransmitting.

{
    ASSERT(seqLE(begin, fromSeq) && seqLE(fromSeq + numBytes, end));
 
    char msgname[32];
    sprintf(msgname, "tcpseg(l=%u)", (unsigned int)numBytes);
 
    Packet *tcpSegment = new Packet(msgname);
    const auto& payload = dataBuffer.peekAt(B(fromSeq - begin), B(numBytes)); // get data from buffer
    tcpSegment->insertAtBack(payload);
    return tcpSegment;
}

Referenced by inet::tcp::TcpConnection::sendSegment().

discardUpTo()

void inet::tcp::TcpSendQueue::discardUpTo ( uint32_t  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.

{
    ASSERT(seqLE(begin, seqNum) && seqLE(seqNum, end));
 
    if (seqNum != begin) {
        dataBuffer.pop(B(seqNum - begin));
        begin = seqNum;
    }
}

Referenced by inet::tcp::TcpConnection::processAckInEstabEtc(), inet::tcp::TcpConnection::processRstInSynReceived(), and inet::tcp::TcpConnection::processSegmentInSynSent().

enqueueAppData()

void inet::tcp::TcpSendQueue::enqueueAppData ( Packet *  msg )

virtual

Called on SEND app command, it inserts in the queue the data the user wants to send.

Implementations of this abstract class will decide what this means: copying actual bytes, just increasing the "last byte queued" variable, or storing cMessage object(s). The msg object should not be referenced after this point (sendQueue may delete it.)

{
    dataBuffer.push(msg->peekDataAt(B(0), msg->getDataLength()));
    end += msg->getByteLength();
    if (seqLess(end, begin))
        throw cRuntimeError("Send queue is full");
    delete msg;
}

Referenced by inet::tcp::TcpConnection::process_SEND().

getBufferEndSeq()

uint32_t inet::tcp::TcpSendQueue::getBufferEndSeq ( ) const

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.)

{
    return end;
}

Referenced by inet::tcp::TcpConnection::process_CLOSE(), inet::tcp::TcpConnection::processRstInSynReceived(), inet::tcp::TcpConnection::retransmitData(), and inet::tcp::TcpConnection::retransmitOneSegment().

getBufferStartSeq()

uint32_t inet::tcp::TcpSendQueue::getBufferStartSeq ( ) const

virtual

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

{
    return begin;
}

Referenced by inet::tcp::TcpConnection::sendSegment().

getBytesAvailable()

uint32_t inet::tcp::TcpSendQueue::getBytesAvailable ( uint32_t  fromSeq ) const

virtual

Utility function: returns how many bytes are available in the queue, from (and including) the given sequence number.

{
    return seqLess(fromSeq, end) ? end - fromSeq : 0;
}

Referenced by inet::tcp::TcpConnection::isSendQueueEmpty(), inet::tcp::TcpConnection::nextSeg(), inet::tcp::TcpConnection::process_SEND(), inet::tcp::TcpConnection::retransmitData(), inet::tcp::TcpConnection::retransmitOneSegment(), inet::tcp::TcpConnection::sendData(), inet::tcp::TcpConnection::sendOneNewSegment(), inet::tcp::TcpConnection::sendProbe(), and inet::tcp::TcpConnection::sendSegment().

getDataBuffer()

virtual ChunkQueue& inet::tcp::TcpSendQueue::getDataBuffer ( )

inlinevirtual

{ return dataBuffer; }

init()

void inet::tcp::TcpSendQueue::init ( uint32_t  startSeq )

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.

{
    begin = startSeq;
    end = startSeq;
    dataBuffer.clear(); // clear dataBuffer
}

Referenced by inet::tcp::TcpConnection::selectInitialSeqNum().

setConnection()

virtual void inet::tcp::TcpSendQueue::setConnection ( TcpConnection *  _conn )

inlinevirtual

Set the connection that owns this queue.

{ conn = _conn; }

Referenced by inet::tcp::TcpConnection::initClonedConnection(), and inet::tcp::TcpConnection::initConnection().

str()

std::string inet::tcp::TcpSendQueue::str ( ) const

overridevirtual

Returns a string with the region stored.

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

Member Data Documentation

begin

uint32_t inet::tcp::TcpSendQueue::begin = 0

protected

Referenced by createSegmentWithBytes(), discardUpTo(), enqueueAppData(), getBufferStartSeq(), init(), and str().

conn

TcpConnection* inet::tcp::TcpSendQueue::conn = nullptr

protected

dataBuffer

ChunkQueue inet::tcp::TcpSendQueue::dataBuffer

protected

Referenced by createSegmentWithBytes(), discardUpTo(), enqueueAppData(), init(), and str().

end

uint32_t inet::tcp::TcpSendQueue::end = 0

protected

Referenced by createSegmentWithBytes(), discardUpTo(), enqueueAppData(), getBufferEndSeq(), getBytesAvailable(), init(), and str().

---

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

• TcpSendQueue.h
• TcpSendQueue.cc