session-rtp.cc

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/* -*-  Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */
/*
 * Copyright (c) 1997 Regents of the University of California.
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 * 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 MASH Research
 *      Group at the University of California Berkeley.
 * 4. Neither the name of the University nor of the Research Group may be
 *    used to endorse or promote products derived from this software without
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#ifndef lint
static const char rcsid[] =
    "@(#) $Header: /nfs/jade/vint/CVSROOT/ns-2/common/session-rtp.cc,v 1.13 2000/09/01 03:04:07 haoboy Exp $";
#endif

#include <stdlib.h>
#include "packet.h"
#include "ip.h"
#include "rtp.h"

static class RTPSourceClass : public TclClass {
public:
        RTPSourceClass() : TclClass("RTPSource") {}
        TclObject* create(int argc, const char*const* argv) {
                if (argc >= 5)
                        return (new RTPSource(atoi(argv[4])));

                return 0;
        }
} class_rtp_source;

static class RTPSessionClass : public TclClass {
public:
        RTPSessionClass() : TclClass("Session/RTP") {}
        TclObject* create(int, const char*const*) {
                return (new RTPSession());
        }
} class_rtp_session;

RTPSession::RTPSession() 
        : allsrcs_(0), localsrc_(0), last_np_(0)
{
}

RTPSession::~RTPSession() 
{
        while (allsrcs_ != 0) {
                RTPSource* p = allsrcs_;
                allsrcs_ = allsrcs_->next;
                delete p;
        }
        delete localsrc_;
}

void RTPSession::localsrc_update(int)
{
        localsrc_->np(1);
}

#define RTCP_HDRSIZE 8
#define RTCP_SR_SIZE 20
#define RTCP_RR_SIZE 48

int RTPSession::build_report(int bye)
{
        int nsrc = 0;
        int nrr = 0;
        int len = RTCP_HDRSIZE;
        int we_sent = 0;
        if (localsrc_->np() != last_np_) {
                last_np_ = localsrc_->np();
                we_sent = 1;
                len += RTCP_SR_SIZE;
        }
        for (RTPSource* sp = allsrcs_; sp != 0; sp = sp->next) {
                ++nsrc;
                int received = sp->np() - sp->snp();
                if (received == 0) {
                        continue;
                }
                sp->snp(sp->np());
                len += RTCP_RR_SIZE;
                if (++nrr >= 31)
                        break;
        }

        if (bye) 
                len += build_bye();
        else 
                len += build_sdes();

        Tcl::instance().evalf("%s adapt-timer %d %d %d", name(), 
                              nsrc, nrr, we_sent);
        Tcl::instance().evalf("%s sample-size %d", name(), len);

        return (len);
}

int RTPSession::build_bye() 
{
        return (8);
}

int RTPSession::build_sdes()
{
        /* XXX We'll get to this later... */
        return (20);
}

void RTPSession::recv(Packet* p, Handler*)
{
        hdr_rtp *rh = hdr_rtp::access(p);
        u_int32_t srcid = rh->srcid();
        RTPSource* s = lookup(srcid);
        if (s == 0) {
                Tcl& tcl = Tcl::instance();
                tcl.evalf("%s new-source %d", name(), srcid);
                s = (RTPSource*)TclObject::lookup(tcl.result());
        }
        s->np(1);
        s->ehsr(rh->seqno());
        Packet::free(p);
}

void RTPSession::recv_ctrl(Packet* p)
{
        hdr_cmn* ch = hdr_cmn::access(p);
        Tcl::instance().evalf("%s sample-size %d", name(), ch->size());
        Packet::free(p);
}

/* XXX Should hash this... */
RTPSource* RTPSession::lookup(u_int32_t srcid)
{
        RTPSource *p;
        for (p = allsrcs_; p != 0; p = p->next)
                if (p->srcid() == srcid)
                        return (p);

        return (0);
}

void RTPSession::enter(RTPSource* s)
{
        s->next = allsrcs_;
        allsrcs_ = s;
}

int RTPSession::command(int argc, const char*const* argv)
{
        if (argc == 3) {
                if (strcmp(argv[1], "enter") == 0) {
                        RTPSource* s = (RTPSource*)TclObject::lookup(argv[2]);
                        enter(s);
                        return (TCL_OK);
                }
                if (strcmp(argv[1], "localsrc") == 0) {
                        localsrc_ = (RTPSource*)TclObject::lookup(argv[2]);
                        enter(localsrc_);
                        return (TCL_OK);
                }
        }
        return (TclObject::command(argc, argv));
}

RTPSource::RTPSource(u_int32_t srcid)
        : next(0), np_(0), snp_(0), ehsr_(-1)
{
        bind("srcid_", (int*)&srcid_);
        srcid_ = srcid;
}

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