network_cmds-176.tar.gz

[apple/network_cmds.git] / timed.tproj / timed.tproj / master.c

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*-
 * Copyright (c) 1985, 1993
 *      The 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 University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    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.
 */

#ifndef lint
static char sccsid[] = "@(#)master.c    8.1 (Berkeley) 6/6/93";
#endif /* not lint */

#ifdef sgi
#ident "$Revision: 1.1.1.1 $"
#endif

#include "globals.h"
#include <sys/file.h>
#include <sys/types.h>
#include <sys/times.h>
#include <setjmp.h>
#ifdef sgi
#include <sys/schedctl.h>
#endif /* sgi */
#include <utmp.h>
#include "pathnames.h"

extern int measure_delta;
extern jmp_buf jmpenv;
extern int Mflag;
extern int justquit;

static int dictate;
static int slvcount;                    /* slaves listening to our clock */

static void mchgdate __P((struct tsp *));

#ifdef sgi
extern void logwtmp __P((struct timeval *, struct timeval *));
#else
extern void logwtmp __P((char *, char *, char *));
#endif /* sgi */

/*
 * The main function of `master' is to periodically compute the differences
 * (deltas) between its clock and the clocks of the slaves, to compute the
 * network average delta, and to send to the slaves the differences between
 * their individual deltas and the network delta.
 * While waiting, it receives messages from the slaves (i.e. requests for
 * master's name, remote requests to set the network time, ...), and
 * takes the appropriate action.
 */
int
master()
{
        struct hosttbl *htp;
        long pollingtime;
#define POLLRATE 4
        int polls;
        struct timeval wait, ntime;
        struct tsp *msg, *answer, to;
        char newdate[32];
        struct sockaddr_in taddr;
        char tname[MAXHOSTNAMELEN];
        struct netinfo *ntp;
        int i;

        syslog(LOG_NOTICE, "This machine is master");
        if (trace)
                fprintf(fd, "This machine is master\n");
        for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
                if (ntp->status == MASTER)
                        masterup(ntp);
        }
        (void)gettimeofday(&ntime, 0);
        pollingtime = ntime.tv_sec+3;
        if (justquit)
                polls = 0;
        else
                polls = POLLRATE-1;

/* Process all outstanding messages before spending the long time necessary
 *      to update all timers.
 */
loop:
        (void)gettimeofday(&ntime, 0);
        wait.tv_sec = pollingtime - ntime.tv_sec;
        if (wait.tv_sec < 0)
                wait.tv_sec = 0;
        wait.tv_usec = 0;
        msg = readmsg(TSP_ANY, ANYADDR, &wait, 0);
        if (!msg) {
                (void)gettimeofday(&ntime, 0);
                if (ntime.tv_sec >= pollingtime) {
                        pollingtime = ntime.tv_sec + SAMPLEINTVL;
                        get_goodgroup(0);

/* If a bogus master told us to quit, we can have decided to ignore a
 * network.  Therefore, periodically try to take over everything.
 */
                        polls = (polls + 1) % POLLRATE;
                        if (0 == polls && nignorednets > 0) {
                                trace_msg("Looking for nets to re-master\n");
                                for (ntp = nettab; ntp; ntp = ntp->next) {
                                        if (ntp->status == IGNORE
                                            || ntp->status == NOMASTER) {
                                                lookformaster(ntp);
                                                if (ntp->status == MASTER) {
                                                        masterup(ntp);
                                                        polls = POLLRATE-1;
                                                }
                                        }
                                        if (ntp->status == MASTER
                                            && --ntp->quit_count < 0)
                                                ntp->quit_count = 0;
                                }
                                if (polls != 0)
                                        setstatus();
                        }

                        synch(0L);

                        for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
                                to.tsp_type = TSP_LOOP;
                                to.tsp_vers = TSPVERSION;
                                to.tsp_seq = sequence++;
                                to.tsp_hopcnt = MAX_HOPCNT;
                                (void)strcpy(to.tsp_name, hostname);
                                bytenetorder(&to);
                                if (sendto(sock, (char *)&to,
                                           sizeof(struct tsp), 0,
                                           (struct sockaddr*)&ntp->dest_addr,
                                           sizeof(ntp->dest_addr)) < 0) {
                                   trace_sendto_err(ntp->dest_addr.sin_addr);
                                }
                        }
                }


        } else {
                switch (msg->tsp_type) {

                case TSP_MASTERREQ:
                        break;

                case TSP_SLAVEUP:
                        newslave(msg);
                        break;

                case TSP_SETDATE:
                        /*
                         * XXX check to see it is from ourself
                         */
#ifdef sgi
                        (void)cftime(newdate, "%D %T", &msg->tsp_time.tv_sec);
#else
                        (void)strcpy(newdate, ctime(&msg->tsp_time.tv_sec));
#endif /* sgi */
                        if (!good_host_name(msg->tsp_name)) {
                                syslog(LOG_NOTICE,
                                       "attempted date change by %s to %s",
                                       msg->tsp_name, newdate);
                                spreadtime();
                                break;
                        }

                        mchgdate(msg);
                        (void)gettimeofday(&ntime, 0);
                        pollingtime = ntime.tv_sec + SAMPLEINTVL;
                        break;

                case TSP_SETDATEREQ:
                        if (!fromnet || fromnet->status != MASTER)
                                break;
#ifdef sgi
                        (void)cftime(newdate, "%D %T", &msg->tsp_time.tv_sec);
#else
                        (void)strcpy(newdate, ctime(&msg->tsp_time.tv_sec));
#endif /* sgi */
                        htp = findhost(msg->tsp_name);
                        if (htp == 0) {
                                syslog(LOG_ERR,
                                       "attempted SET DATEREQ by uncontrolled %s to %s",
                                       msg->tsp_name, newdate);
                                break;
                        }
                        if (htp->seq == msg->tsp_seq)
                                break;
                        htp->seq = msg->tsp_seq;
                        if (!htp->good) {
                                syslog(LOG_NOTICE,
                                "attempted SET DATEREQ by untrusted %s to %s",
                                       msg->tsp_name, newdate);
                                spreadtime();
                                break;
                        }

                        mchgdate(msg);
                        (void)gettimeofday(&ntime, 0);
                        pollingtime = ntime.tv_sec + SAMPLEINTVL;
                        break;

                case TSP_MSITE:
                        xmit(TSP_ACK, msg->tsp_seq, &from);
                        break;

                case TSP_MSITEREQ:
                        break;

                case TSP_TRACEON:
                        traceon();
                        break;

                case TSP_TRACEOFF:
                        traceoff("Tracing ended at %s\n");
                        break;

                case TSP_ELECTION:
                        if (!fromnet)
                                break;
                        if (fromnet->status == MASTER) {
                                pollingtime = 0;
                                (void)addmach(msg->tsp_name, &from,fromnet);
                        }
                        taddr = from;
                        (void)strcpy(tname, msg->tsp_name);
                        to.tsp_type = TSP_QUIT;
                        (void)strcpy(to.tsp_name, hostname);
                        answer = acksend(&to, &taddr, tname,
                                         TSP_ACK, 0, 1);
                        if (answer == NULL) {
                                syslog(LOG_ERR, "election error by %s",
                                       tname);
                        }
                        break;

                case TSP_CONFLICT:
                        /*
                         * After a network partition, there can be
                         * more than one master: the first slave to
                         * come up will notify here the situation.
                         */
                        if (!fromnet || fromnet->status != MASTER)
                                break;
                        (void)strcpy(to.tsp_name, hostname);

                        /* The other master often gets into the same state,
                         * with boring results if we stay at it forever.
                         */
                        ntp = fromnet;  /* (acksend() can leave fromnet=0 */
                        for (i = 0; i < 3; i++) {
                                to.tsp_type = TSP_RESOLVE;
                                (void)strcpy(to.tsp_name, hostname);
                                answer = acksend(&to, &ntp->dest_addr,
                                                 ANYADDR, TSP_MASTERACK,
                                                 ntp, 0);
                                if (!answer)
                                        break;
                                htp = addmach(answer->tsp_name,&from,ntp);
                                to.tsp_type = TSP_QUIT;
                                msg = acksend(&to, &htp->addr, htp->name,
                                              TSP_ACK, 0, htp->noanswer);
                                if (msg == NULL) {
                                        syslog(LOG_ERR,
                                    "no response from %s to CONFLICT-QUIT",
                                               htp->name);
                                }
                        }
                        masterup(ntp);
                        pollingtime = 0;
                        break;

                case TSP_RESOLVE:
                        if (!fromnet || fromnet->status != MASTER)
                                break;
                        /*
                         * do not want to call synch() while waiting
                         * to be killed!
                         */
                        (void)gettimeofday(&ntime, (struct timezone *)0);
                        pollingtime = ntime.tv_sec + SAMPLEINTVL;
                        break;

                case TSP_QUIT:
                        doquit(msg);            /* become a slave */
                        break;

                case TSP_LOOP:
                        if (!fromnet || fromnet->status != MASTER
                            || !strcmp(msg->tsp_name, hostname))
                                break;
                        /*
                         * We should not have received this from a net
                         * we are master on.  There must be two masters.
                         */
                        htp = addmach(msg->tsp_name, &from,fromnet);
                        to.tsp_type = TSP_QUIT;
                        (void)strcpy(to.tsp_name, hostname);
                        answer = acksend(&to, &htp->addr, htp->name,
                                         TSP_ACK, 0, 1);
                        if (!answer) {
                                syslog(LOG_WARNING,
                                "loop breakage: no reply from %s=%s to QUIT",
                                    htp->name, inet_ntoa(htp->addr.sin_addr));
                                (void)remmach(htp);
                        }

                case TSP_TEST:
                        if (trace) {
                                fprintf(fd,
                "\tnets = %d, masters = %d, slaves = %d, ignored = %d\n",
                nnets, nmasternets, nslavenets, nignorednets);
                                setstatus();
                        }
                        pollingtime = 0;
                        polls = POLLRATE-1;
                        break;

                default:
                        if (trace) {
                                fprintf(fd, "garbage message: ");
                                print(msg, &from);
                        }
                        break;
                }
        }
        goto loop;
}


/*
 * change the system date on the master
 */
static void
mchgdate(msg)
        struct tsp *msg;
{
        char tname[MAXHOSTNAMELEN];
        char olddate[32];
        struct timeval otime, ntime;

        (void)strcpy(tname, msg->tsp_name);

        xmit(TSP_DATEACK, msg->tsp_seq, &from);

        (void)strcpy(olddate, date());

        /* adjust time for residence on the queue */
        (void)gettimeofday(&otime, 0);
        adj_msg_time(msg,&otime);

        timevalsub(&ntime, &msg->tsp_time, &otime);
        if (ntime.tv_sec < MAXADJ && ntime.tv_sec > -MAXADJ) {
                /*
                 * do not change the clock if we can adjust it
                 */
                dictate = 3;
                synch(tvtomsround(ntime));
        } else {
#ifdef sgi
                if (0 > settimeofday(&msg->tsp_time, 0)) {
                        syslog(LOG_ERR, "settimeofday(): %m");
                }
                logwtmp(&otime, &msg->tsp_time);
#else
                logwtmp("|", "date", "");
                (void)settimeofday(&msg->tsp_time, 0);
                logwtmp("}", "date", "");
#endif /* sgi */
                spreadtime();
        }

        syslog(LOG_NOTICE, "date changed by %s from %s",
               tname, olddate);
}


/*
 * synchronize all of the slaves
 */
void
synch(mydelta)
        long mydelta;
{
        struct hosttbl *htp;
        int measure_status;
        struct timeval check, stop, wait;
#ifdef sgi
        int pri;
#endif /* sgi */

        if (slvcount > 0) {
                if (trace)
                        fprintf(fd, "measurements starting at %s\n", date());
                (void)gettimeofday(&check, 0);
#ifdef sgi
                /* run fast to get good time */
                pri = schedctl(NDPRI,0,NDPHIMIN);
                if (pri < 0)
                        syslog(LOG_ERR, "schedctl(): %m");
#endif /* sgi */
                for (htp = self.l_fwd; htp != &self; htp = htp->l_fwd) {
                        if (htp->noanswer != 0) {
                                measure_status = measure(500, 100,
                                                         htp->name,
                                                         &htp->addr,0);
                        } else {
                                measure_status = measure(3000, 100,
                                                         htp->name,
                                                         &htp->addr,0);
                        }
                        if (measure_status != GOOD) {
                                /* The slave did not respond.  We have
                                 * just wasted lots of time on it.
                                 */
                                htp->delta = HOSTDOWN;
                                if (++htp->noanswer >= LOSTHOST) {
                                        if (trace) {
                                                fprintf(fd,
                                        "purging %s for not answering ICMP\n",
                                                        htp->name);
                                                (void)fflush(fd);
                                        }
                                        htp = remmach(htp);
                                }
                        } else {
                                htp->delta = measure_delta;
                        }
                        (void)gettimeofday(&stop, 0);
                        timevalsub(&stop, &stop, &check);
                        if (stop.tv_sec >= 1) {
                                if (trace)
                                        (void)fflush(fd);
                                /*
                                 * ack messages periodically
                                 */
                                wait.tv_sec = 0;
                                wait.tv_usec = 0;
                                if (0 != readmsg(TSP_TRACEON,ANYADDR,
                                                 &wait,0))
                                        traceon();
                                (void)gettimeofday(&check, 0);
                        }
                }
#ifdef sgi
                if (pri >= 0)
                        (void)schedctl(NDPRI,0,pri);
#endif /* sgi */
                if (trace)
                        fprintf(fd, "measurements finished at %s\n", date());
        }
        if (!(status & SLAVE)) {
                if (!dictate) {
                        mydelta = networkdelta();
                } else {
                        dictate--;
                }
        }
        if (trace && (mydelta != 0 || (status & SLAVE)))
                fprintf(fd,"local correction of %ld ms.\n", mydelta);
        correct(mydelta);
}

/*
 * sends the time to each slave after the master
 * has received the command to set the network time
 */
void
spreadtime()
{
        struct hosttbl *htp;
        struct tsp to;
        struct tsp *answer;

/* Do not listen to the consensus after forcing the time.  This is because
 *      the consensus takes a while to reach the time we are dictating.
 */
        dictate = 2;
        for (htp = self.l_fwd; htp != &self; htp = htp->l_fwd) {
                to.tsp_type = TSP_SETTIME;
                (void)strcpy(to.tsp_name, hostname);
                (void)gettimeofday(&to.tsp_time, 0);
                answer = acksend(&to, &htp->addr, htp->name,
                                 TSP_ACK, 0, htp->noanswer);
                if (answer == 0) {
                        /* We client does not respond, then we have
                         * just wasted lots of time on it.
                         */
                        syslog(LOG_WARNING,
                               "no reply to SETTIME from %s", htp->name);
                        if (++htp->noanswer >= LOSTHOST) {
                                if (trace) {
                                        fprintf(fd,
                                             "purging %s for not answering",
                                                htp->name);
                                        (void)fflush(fd);
                                }
                                htp = remmach(htp);
                        }
                }
        }
}

void
prthp(delta)
        clock_t delta;
{
        static time_t next_time;
        time_t this_time;
        struct tms tm;
        struct hosttbl *htp;
        int length, l;
        int i;

        if (!fd)                        /* quit if tracing already off */
                return;

        this_time = times(&tm);
        if (this_time + delta < next_time)
                return;
        next_time = this_time + CLK_TCK;

        fprintf(fd, "host table: %d entries at %s\n", slvcount, date());
        htp = self.l_fwd;
        length = 1;
        for (i = 1; i <= slvcount; i++, htp = htp->l_fwd) {
                l = strlen(htp->name) + 1;
                if (length+l >= 80) {
                        fprintf(fd, "\n");
                        length = 0;
                }
                length += l;
                fprintf(fd, " %s", htp->name);
        }
        fprintf(fd, "\n");
}


static struct hosttbl *newhost_hash;
static struct hosttbl *lasthfree = &hosttbl[0];


struct hosttbl *                        /* answer or 0 */
findhost(name)
        char *name;
{
        int i, j;
        struct hosttbl *htp;
        char *p;

        j= 0;
        for (p = name, i = 0; i < 8 && *p != '\0'; i++, p++)
                j = (j << 2) ^ *p;
        newhost_hash = &hosttbl[j % NHOSTS];

        htp = newhost_hash;
        if (htp->name[0] == '\0')
                return(0);
        do {
                if (!strcmp(name, htp->name))
                        return(htp);
                htp = htp->h_fwd;
        } while (htp != newhost_hash);
        return(0);
}

/*
 * add a host to the list of controlled machines if not already there
 */
struct hosttbl *
addmach(name, addr, ntp)
        char *name;
        struct sockaddr_in *addr;
        struct netinfo *ntp;
{
        struct hosttbl *ret, *p, *b, *f;

        ret = findhost(name);
        if (ret == 0) {
                if (slvcount >= NHOSTS) {
                        if (trace) {
                                fprintf(fd, "no more slots in host table\n");
                                prthp(CLK_TCK);
                        }
                        syslog(LOG_ERR, "no more slots in host table");
                        Mflag = 0;
                        longjmp(jmpenv, 2); /* give up and be a slave */
                }

                /* if our home hash slot is occupied, find a free entry
                 * in the hash table
                 */
                if (newhost_hash->name[0] != '\0') {
                        do {
                                ret = lasthfree;
                                if (++lasthfree > &hosttbl[NHOSTS])
                                        lasthfree = &hosttbl[1];
                        } while (ret->name[0] != '\0');

                        if (!newhost_hash->head) {
                                /* Move an interloper using our home.  Use
                                 * scratch pointers in case the new head is
                                 * pointing to itself.
                                 */
                                f = newhost_hash->h_fwd;
                                b = newhost_hash->h_bak;
                                f->h_bak = ret;
                                b->h_fwd = ret;
                                f = newhost_hash->l_fwd;
                                b = newhost_hash->l_bak;
                                f->l_bak = ret;
                                b->l_fwd = ret;
                                bcopy(newhost_hash,ret,sizeof(*ret));
                                ret = newhost_hash;
                                ret->head = 1;
                                ret->h_fwd = ret;
                                ret->h_bak = ret;
                        } else {
                                /* link to an existing chain in our home
                                 */
                                ret->head = 0;
                                p = newhost_hash->h_bak;
                                ret->h_fwd = newhost_hash;
                                ret->h_bak = p;
                                p->h_fwd = ret;
                                newhost_hash->h_bak = ret;
                        }
                } else {
                        ret = newhost_hash;
                        ret->head = 1;
                        ret->h_fwd = ret;
                        ret->h_bak = ret;
                }
                ret->addr = *addr;
                ret->ntp = ntp;
                (void)strncpy(ret->name, name, sizeof(ret->name));
                ret->good = good_host_name(name);
                ret->l_fwd = &self;
                ret->l_bak = self.l_bak;
                self.l_bak->l_fwd = ret;
                self.l_bak = ret;
                slvcount++;

                ret->noanswer = 0;
                ret->need_set = 1;

        } else {
                ret->noanswer = (ret->noanswer != 0);
        }

        /* need to clear sequence number anyhow */
        ret->seq = 0;
        return(ret);
}

/*
 * remove the machine with the given index in the host table.
 */
struct hosttbl *
remmach(htp)
        struct hosttbl *htp;
{
        struct hosttbl *lprv, *hnxt, *f, *b;

        if (trace)
                fprintf(fd, "remove %s\n", htp->name);

        /* get out of the lists */
        htp->l_fwd->l_bak = lprv = htp->l_bak;
        htp->l_bak->l_fwd = htp->l_fwd;
        htp->h_fwd->h_bak = htp->h_bak;
        htp->h_bak->h_fwd = hnxt = htp->h_fwd;

        /* If we are in the home slot, pull up the chain */
        if (htp->head && hnxt != htp) {
                if (lprv == hnxt)
                        lprv = htp;

                /* Use scratch pointers in case the new head is pointing to
                 * itself.
                 */
                f = hnxt->h_fwd;
                b = hnxt->h_bak;
                f->h_bak = htp;
                b->h_fwd = htp;
                f = hnxt->l_fwd;
                b = hnxt->l_bak;
                f->l_bak = htp;
                b->l_fwd = htp;
                hnxt->head = 1;
                bcopy(hnxt, htp, sizeof(*htp));
                lasthfree = hnxt;
        } else {
                lasthfree = htp;
        }

        lasthfree->name[0] = '\0';
        lasthfree->h_fwd = 0;
        lasthfree->l_fwd = 0;
        slvcount--;

        return lprv;
}


/*
 * Remove all the machines from the host table that exist on the given
 * network.  This is called when a master transitions to a slave on a
 * given network.
 */
void
rmnetmachs(ntp)
        struct netinfo *ntp;
{
        struct hosttbl *htp;

        if (trace)
                prthp(CLK_TCK);
        for (htp = self.l_fwd; htp != &self; htp = htp->l_fwd) {
                if (ntp == htp->ntp)
                        htp = remmach(htp);
        }
        if (trace)
                prthp(CLK_TCK);
}

void
masterup(net)
        struct netinfo *net;
{
        xmit(TSP_MASTERUP, 0, &net->dest_addr);

        /*
         * Do not tell new slaves our time for a while.  This ensures
         * we do not tell them to start using our time, before we have
         * found a good master.
         */
        (void)gettimeofday(&net->slvwait, 0);
}

void
newslave(msg)
        struct tsp *msg;
{
        struct hosttbl *htp;
        struct tsp *answer, to;
        struct timeval now;

        if (!fromnet || fromnet->status != MASTER)
                return;

        htp = addmach(msg->tsp_name, &from,fromnet);
        htp->seq = msg->tsp_seq;
        if (trace)
                prthp(0);

        /*
         * If we are stable, send our time to the slave.
         * Do not go crazy if the date has been changed.
         */
        (void)gettimeofday(&now, 0);
        if (now.tv_sec >= fromnet->slvwait.tv_sec+3
            || now.tv_sec < fromnet->slvwait.tv_sec) {
                to.tsp_type = TSP_SETTIME;
                (void)strcpy(to.tsp_name, hostname);
                (void)gettimeofday(&to.tsp_time, 0);
                answer = acksend(&to, &htp->addr,
                                 htp->name, TSP_ACK,
                                 0, htp->noanswer);
                if (answer) {
                        htp->need_set = 0;
                } else {
                        syslog(LOG_WARNING,
                               "no reply to initial SETTIME from %s",
                               htp->name);
                        htp->noanswer = LOSTHOST;
                }
        }
}


/*
 * react to a TSP_QUIT:
 */
void
doquit(msg)
        struct tsp *msg;
{
        if (fromnet->status == MASTER) {
                if (!good_host_name(msg->tsp_name)) {
                        if (fromnet->quit_count <= 0) {
                                syslog(LOG_NOTICE,"untrusted %s told us QUIT",
                                       msg->tsp_name);
                                suppress(&from, msg->tsp_name, fromnet);
                                fromnet->quit_count = 1;
                                return;
                        }
                        syslog(LOG_NOTICE, "untrusted %s told us QUIT twice",
                               msg->tsp_name);
                        fromnet->quit_count = 2;
                        fromnet->status = NOMASTER;
                } else {
                        fromnet->status = SLAVE;
                }
                rmnetmachs(fromnet);
                longjmp(jmpenv, 2);             /* give up and be a slave */

        } else {
                if (!good_host_name(msg->tsp_name)) {
                        syslog(LOG_NOTICE, "untrusted %s told us QUIT",
                               msg->tsp_name);
                        fromnet->quit_count = 2;
                }
        }
}

void
traceon()
{
        if (!fd) {
                fd = fopen(_PATH_TIMEDLOG, "w");
                if (!fd) {
                        trace = 0;
                        return;
                }
                fprintf(fd,"Tracing started at %s\n", date());
        }
        trace = 1;
        get_goodgroup(1);
        setstatus();
        prthp(CLK_TCK);
}


void
traceoff(msg)
        char *msg;
{
        get_goodgroup(1);
        setstatus();
        prthp(CLK_TCK);
        if (trace) {
                fprintf(fd, msg, date());
                (void)fclose(fd);
                fd = 0;
        }
#ifdef GPROF
        moncontrol(0);
        _mcleanup();
        moncontrol(1);
#endif
        trace = OFF;
}


#ifdef sgi
void
logwtmp(otime, ntime)
        struct timeval *otime, *ntime;
{
        static struct utmp wtmp[2] = {
                {"","",OTIME_MSG,0,OLD_TIME,0,0,0},
                {"","",NTIME_MSG,0,NEW_TIME,0,0,0}
        };
        static char *wtmpfile = WTMP_FILE;
        int f;

        wtmp[0].ut_time = otime->tv_sec + (otime->tv_usec + 500000) / 1000000;
        wtmp[1].ut_time = ntime->tv_sec + (ntime->tv_usec + 500000) / 1000000;
        if (wtmp[0].ut_time == wtmp[1].ut_time)
                return;

        setutent();
        (void)pututline(&wtmp[0]);
        (void)pututline(&wtmp[1]);
        endutent();
        if ((f = open(wtmpfile, O_WRONLY|O_APPEND)) >= 0) {
                (void) write(f, (char *)wtmp, sizeof(wtmp));
                (void) close(f);
        }
}
#endif /* sgi */