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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