/Users/yzchen/ns/ns-allinone-2.33/ns-2.33/tcp/tcp-session.h

/* -*-  Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */
/*
 * Copyright (c) 1997 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the Daedalus Research
 *      Group at the University of California Berkeley.
 * 4. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS 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, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * Contributed by the Daedalus Research Group, http://daedalus.cs.berkeley.edu
 *
 * @(#) $Header: /cvsroot/nsnam/ns-2/tcp/tcp-session.h,v 1.8 1999/09/09 03:25:26 salehi Exp $ (UCB)
 */

#ifndef nc_tcp_session_h
#define ns_tcp_session_h

#include "agent.h"
#include "timer-handler.h"
#include "chost.h"

#define FINE_ROUND_ROBIN 1
#define COARSE_ROUND_ROBIN 2
#define RANDOM 3

class TcpSessionAgent;

class SessionRtxTimer : public TimerHandler {
public: 
        SessionRtxTimer(TcpSessionAgent *a) : TimerHandler() { a_ = a; }
protected:
        virtual void expire(Event *e);
        TcpSessionAgent *a_;
};

class SessionResetTimer : public TimerHandler {
public: 
        SessionResetTimer(TcpSessionAgent *a) : TimerHandler() { a_ = a; }
protected:
        virtual void expire(Event *e);
        TcpSessionAgent *a_;
};

class SessionBurstSndTimer : public TimerHandler {
public: 
        SessionBurstSndTimer(TcpSessionAgent *a) : TimerHandler() { a_ = a; }
protected:
        virtual void expire(Event *e);
        TcpSessionAgent *a_;
};

/*
 * This class implements the notion of a TCP session. It integrates congestion 
 * control and loss detection functionality across the one or more IntTcp 
 * connections that comprise the session.
 */
class TcpSessionAgent : public CorresHost {
public:
        TcpSessionAgent();
        int command(int argc, const char*const* argv);
        void reset_rtx_timer(int mild, int backoff = 1); /* XXX mild needed ? */
        void set_rtx_timer();
        void cancel_rtx_timer();
        void cancel_timers();
        void newack(Packet *pkt);
        int fs_pkt();
        void rtt_update_exact(double tao);
        void timeout(int tno);
        virtual Segment* add_pkts(int size, int seqno, int sessionSeqno, int daddr, 
                        int dport, int sport, double ts, IntTcpAgent *sender); 
        virtual void add_agent(IntTcpAgent *agent, int size, double winMult,
                        int winInc, int ssthresh);
        int window();
        void set_weight(IntTcpAgent *tcp, int wt);
        void reset_dyn_weights();
        IntTcpAgent *who_to_snd(int how);
        void send_much(IntTcpAgent *agent, int force, int reason); 
        void recv(IntTcpAgent *agent, Packet *pkt, int amt_data_acked);
        void setflags(Packet *pkt);
        int findSessionSeqno(IntTcpAgent *sender, int seqno);
        void removeSessionSeqno(int sessionSeqno);
        void quench(int how, IntTcpAgent *sender, int seqno);
        virtual void traceVar(TracedVar* v);

//      inline nsaddr_t& addr() {return addr_;}
//      inline nsaddr_t& dst() {return dst_;}
        static Islist<TcpSessionAgent> sessionList_;

protected:
        SessionRtxTimer rtx_timer_;
        SessionBurstSndTimer burstsnd_timer_;
        int sessionSeqno_;
        double last_send_time_;
        Segment *last_seg_sent_;
        IntTcpAgent *curConn_;
        int numConsecSegs_;
        int schedDisp_;
        int wtSum_;
        int dynWtSum_;
};

#endif