usr/src/usr.sbin/timed/timed/correct.c

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#ifndef lint
static char sccsid[] = "@(#)correct.c   1.1 (Berkeley) %G%";
#endif not lint

#include "globals.h"
#include <protocols/timed.h>

extern int slvcount;
extern struct host hp[];
extern char hostname[];
extern struct sockaddr_in server;
#ifdef MEASURE
extern FILE *fp;
#endif

/*
 * `correct' sends to the slaves the corrections for their clocks
 */

correct(avdelta)
long avdelta;
{
        int i;
        int corr;
        char *strcpy();
        struct timeval adjlocal;
        struct tsp msgs;
        struct timeval mstotvround();
        struct tsp *answer, *acksend();

#ifdef MEASURE
        for(i=0; i<slvcount; i++) {
                if (hp[i].delta == HOSTDOWN)
                        fprintf(fp, "%s\t", "down");
                else {
                        fprintf(fp, "%d\t", hp[i].delta);
                }
        }
        fprintf(fp, "\n");
#endif
        corr = avdelta - hp[0].delta;
        adjlocal = mstotvround(&corr);
        adjclock(&adjlocal);
#ifdef MEASURE
        fprintf(fp, "%d\t", corr);
#endif

        for(i=1; i<slvcount; i++) {
                if (hp[i].delta != HOSTDOWN)  {
                        bcopy((char *)&hp[i].addr,
                                        (char *)&(server.sin_addr.s_addr),
                                                hp[i].length);
                        corr = avdelta - hp[i].delta;
                        msgs.tsp_time = mstotvround(&corr);
                        msgs.tsp_type = (u_char)TSP_ADJTIME;
                        (void)strcpy(msgs.tsp_name, hostname);
                        answer = acksend(&msgs, hp[i].name, TSP_ACK);
                        if (answer == NULL) {
                                hp[i].delta = HOSTDOWN;
#ifdef MEASURE
                                fprintf(fp, "%s\t", "down");
                        } else {
                                fprintf(fp, "%d\t", corr);
#endif
                        }
                } else {
#ifdef MEASURE
                        fprintf(fp, "%s\t", "down");
#endif
                }
        }
#ifdef MEASURE
        fprintf(fp, "\n");
        (void)fflush(fp);
#endif
}

/*
 * `mstotvround' rounds up the value of the argument to the
 * nearest multiple of five, and converts it into a timeval
 */

struct timeval mstotvround(x)
int *x;
{
        int temp;
        struct timeval adj;

        temp = *x % 5;
        if (temp >= 3)
                *x = *x-temp+5;
        else {
                if (temp <= -3)
                        *x = *x - temp -5;
                else
                        *x = *x-temp;
        }
        adj.tv_sec = *x/1000;
        adj.tv_usec = (*x-adj.tv_sec*1000)*1000;
        if (adj.tv_usec < 0) {
                adj.tv_usec += 1000000;
                adj.tv_sec--;
        }
        return(adj);
}

adjclock(corr)
struct timeval *corr;
{
        if (timerisset(corr)) {
                if (corr->tv_sec < SAMPLEINTVL/10 &&
                                        corr->tv_sec > - SAMPLEINTVL/10) {
                        (void)adjtime(corr, (struct timeval *)0);
                } else {
                        corr->tv_usec = 0;
                        if (corr->tv_sec > 0)
                                corr->tv_sec = SAMPLEINTVL/10 - 2;
                        else
                                corr->tv_sec = - SAMPLEINTVL/10 + 2;
                        (void)adjtime(corr, (struct timeval *)0);
                        syslog(LOG_WARNING, "timed: adjclock called with too large a parameter\n");
                }
        }
}