freebsd-dev/contrib/ntp/libntp/systime.c
2001-08-29 14:35:15 +00:00

361 lines
7.9 KiB
C

/*
* systime -- routines to fiddle a UNIX clock.
*/
#include "ntp_proto.h" /* for MAX_FREQ */
#include "ntp_machine.h"
#include "ntp_fp.h"
#include "ntp_syslog.h"
#include "ntp_unixtime.h"
#include "ntp_stdlib.h"
#ifdef HAVE_SYS_PARAM_H
# include <sys/param.h>
#endif
#ifdef HAVE_UTMP_H
# include <utmp.h>
#endif /* HAVE_UTMP_H */
#ifdef HAVE_UTMPX_H
# include <utmpx.h>
#endif /* HAVE_UTMPX_H */
int systime_10ms_ticks = 0; /* adj sysclock in 10ms increments */
/*
* These routines (init_systime, get_systime, step_systime, adj_systime)
* implement an interface between the (more or less) system independent
* bits of NTP and the peculiarities of dealing with the Unix system
* clock.
*/
double sys_residual = 0; /* residual from previous adjustment */
/*
* get_systime - return the system time in timestamp format biased by
* the current time offset.
*/
void
get_systime(
l_fp *now
)
{
#if defined(HAVE_CLOCK_GETTIME) || defined(HAVE_GETCLOCK)
struct timespec ts;
#else
struct timeval tv;
#endif
double dtemp;
/*
* We use nanosecond time if we can get it. Watch out for
* rounding wiggles, which may overflow the fraction.
*/
#if defined(HAVE_CLOCK_GETTIME) || defined(HAVE_GETCLOCK)
# ifdef HAVE_CLOCK_GETTIME
(void) clock_gettime(CLOCK_REALTIME, &ts);
# else
(void) getclock(TIMEOFDAY, &ts);
# endif
now->l_i = ts.tv_sec + JAN_1970;
dtemp = ts.tv_nsec * FRAC / 1e9;
if (dtemp >= FRAC)
now->l_i++;
now->l_uf = (u_int32)dtemp;
#else /* HAVE_CLOCK_GETTIME */
(void) GETTIMEOFDAY(&tv, (struct timezone *)0);
now->l_i = tv.tv_sec + JAN_1970;
#if defined RELIANTUNIX_CLOCK || defined SCO5_CLOCK
if (systime_10ms_ticks) {
/* fake better than 10ms resolution by interpolating
accumulated residual (in adj_systime(), see below) */
dtemp = tv.tv_usec / 1e6;
if (sys_residual < 5000e-6 && sys_residual > -5000e-6) {
dtemp += sys_residual;
if (dtemp < 0) {
now->l_i--;
dtemp++;
}
}
dtemp *= FRAC;
} else
#endif
dtemp = tv.tv_usec * FRAC / 1e6;
if (dtemp >= FRAC)
now->l_i++;
now->l_uf = (u_int32)dtemp;
#endif /* HAVE_CLOCK_GETTIME */
}
/*
* adj_systime - called once every second to make system time adjustments.
* Returns 1 if okay, 0 if trouble.
*/
#if !defined SYS_WINNT
int
adj_systime(
double now
)
{
double dtemp;
struct timeval adjtv;
u_char isneg = 0;
struct timeval oadjtv;
/*
* Add the residual from the previous adjustment to the new
* adjustment, bound and round.
*/
dtemp = sys_residual + now;
sys_residual = 0;
if (dtemp < 0) {
isneg = 1;
dtemp = -dtemp;
}
#if defined RELIANTUNIX_CLOCK || defined SCO5_CLOCK
if (systime_10ms_ticks) {
/* accumulate changes until we have enough to adjust a tick */
if (dtemp < 5000e-6) {
if (isneg) sys_residual = -dtemp;
else sys_residual = dtemp;
dtemp = 0;
} else {
if (isneg) sys_residual = 10000e-6 - dtemp;
else sys_residual = dtemp - 10000e-6;
dtemp = 10000e-6;
}
} else
#endif
if (dtemp > NTP_MAXFREQ)
dtemp = NTP_MAXFREQ;
dtemp = dtemp * 1e6 + .5;
if (isneg)
dtemp = -dtemp;
adjtv.tv_sec = 0;
adjtv.tv_usec = (int32)dtemp;
/*
* Here we do the actual adjustment. If for some reason the adjtime()
* call fails, like it is not implemented or something like that,
* we honk to the log. If the previous adjustment did not complete,
* we correct the residual offset.
*/
/* casey - we need a posix type thang here */
if (adjtime(&adjtv, &oadjtv) < 0)
{
msyslog(LOG_ERR, "Can't adjust time (%ld sec, %ld usec): %m",
(long)adjtv.tv_sec, (long)adjtv.tv_usec);
return 0;
}
else {
sys_residual += oadjtv.tv_usec / 1e6;
}
#ifdef DEBUG
if (debug > 6)
printf("adj_systime: adj %.9f -> remaining residual %.9f\n", now, sys_residual);
#endif
return 1;
}
#endif
/*
* step_systime - step the system clock.
*/
int
step_systime(
double now
)
{
struct timeval timetv, adjtv, oldtimetv;
int isneg = 0;
double dtemp;
#if defined(HAVE_CLOCK_GETTIME) || defined(HAVE_GETCLOCK)
struct timespec ts;
#endif
dtemp = sys_residual + now;
if (dtemp < 0) {
isneg = 1;
dtemp = - dtemp;
adjtv.tv_sec = (int32)dtemp;
adjtv.tv_usec = (u_int32)((dtemp - (double)adjtv.tv_sec) *
1e6 + .5);
} else {
adjtv.tv_sec = (int32)dtemp;
adjtv.tv_usec = (u_int32)((dtemp - (double)adjtv.tv_sec) *
1e6 + .5);
}
#if defined(HAVE_CLOCK_GETTIME) || defined(HAVE_GETCLOCK)
#ifdef HAVE_CLOCK_GETTIME
(void) clock_gettime(CLOCK_REALTIME, &ts);
#else
(void) getclock(TIMEOFDAY, &ts);
#endif
timetv.tv_sec = ts.tv_sec;
timetv.tv_usec = ts.tv_nsec / 1000;
#else /* not HAVE_GETCLOCK */
(void) GETTIMEOFDAY(&timetv, (struct timezone *)0);
#endif /* not HAVE_GETCLOCK */
oldtimetv = timetv;
#ifdef DEBUG
if (debug)
printf("step_systime: step %.6f residual %.6f\n", now, sys_residual);
#endif
if (isneg) {
timetv.tv_sec -= adjtv.tv_sec;
timetv.tv_usec -= adjtv.tv_usec;
if (timetv.tv_usec < 0) {
timetv.tv_sec--;
timetv.tv_usec += 1000000;
}
} else {
timetv.tv_sec += adjtv.tv_sec;
timetv.tv_usec += adjtv.tv_usec;
if (timetv.tv_usec >= 1000000) {
timetv.tv_sec++;
timetv.tv_usec -= 1000000;
}
}
if (ntp_set_tod(&timetv, (struct timezone *)0) != 0) {
msyslog(LOG_ERR, "Can't set time of day: %m");
return (0);
}
sys_residual = 0;
#ifdef NEED_HPUX_ADJTIME
/*
* CHECKME: is this correct when called by ntpdate?????
*/
_clear_adjtime();
#endif
/*
* FreeBSD, for example, has:
* struct utmp {
* char ut_line[UT_LINESIZE];
* char ut_name[UT_NAMESIZE];
* char ut_host[UT_HOSTSIZE];
* long ut_time;
* };
* and appends line="|", name="date", host="", time for the OLD
* and appends line="{", name="date", host="", time for the NEW
* to _PATH_WTMP .
*
* Some OSes have utmp, some have utmpx.
*/
/*
* Write old and new time entries in utmp and wtmp if step adjustment
* is greater than one second.
*
* This might become even Uglier...
*/
if (oldtimetv.tv_sec != timetv.tv_sec)
{
#ifdef HAVE_UTMP_H
struct utmp ut;
#endif
#ifdef HAVE_UTMPX_H
struct utmpx utx;
#endif
#ifdef HAVE_UTMP_H
memset((char *)&ut, 0, sizeof(ut));
#endif
#ifdef HAVE_UTMPX_H
memset((char *)&utx, 0, sizeof(utx));
#endif
/* UTMP */
#ifdef UPDATE_UTMP
# ifdef HAVE_PUTUTLINE
ut.ut_type = OLD_TIME;
(void)strcpy(ut.ut_line, OTIME_MSG);
ut.ut_time = oldtimetv.tv_sec;
pututline(&ut);
setutent();
ut.ut_type = NEW_TIME;
(void)strcpy(ut.ut_line, NTIME_MSG);
ut.ut_time = timetv.tv_sec;
pututline(&ut);
endutent();
# else /* not HAVE_PUTUTLINE */
# endif /* not HAVE_PUTUTLINE */
#endif /* UPDATE_UTMP */
/* UTMPX */
#ifdef UPDATE_UTMPX
# ifdef HAVE_PUTUTXLINE
utx.ut_type = OLD_TIME;
(void)strcpy(utx.ut_line, OTIME_MSG);
utx.ut_tv = oldtimetv;
pututxline(&utx);
setutxent();
utx.ut_type = NEW_TIME;
(void)strcpy(utx.ut_line, NTIME_MSG);
utx.ut_tv = timetv;
pututxline(&utx);
endutxent();
# else /* not HAVE_PUTUTXLINE */
# endif /* not HAVE_PUTUTXLINE */
#endif /* UPDATE_UTMPX */
/* WTMP */
#ifdef UPDATE_WTMP
# ifdef HAVE_PUTUTLINE
utmpname(WTMP_FILE);
ut.ut_type = OLD_TIME;
(void)strcpy(ut.ut_line, OTIME_MSG);
ut.ut_time = oldtimetv.tv_sec;
pututline(&ut);
ut.ut_type = NEW_TIME;
(void)strcpy(ut.ut_line, NTIME_MSG);
ut.ut_time = timetv.tv_sec;
pututline(&ut);
endutent();
# else /* not HAVE_PUTUTLINE */
# endif /* not HAVE_PUTUTLINE */
#endif /* UPDATE_WTMP */
/* WTMPX */
#ifdef UPDATE_WTMPX
# ifdef HAVE_PUTUTXLINE
utx.ut_type = OLD_TIME;
utx.ut_tv = oldtimetv;
(void)strcpy(utx.ut_line, OTIME_MSG);
# ifdef HAVE_UPDWTMPX
updwtmpx(WTMPX_FILE, &utx);
# else /* not HAVE_UPDWTMPX */
# endif /* not HAVE_UPDWTMPX */
# else /* not HAVE_PUTUTXLINE */
# endif /* not HAVE_PUTUTXLINE */
# ifdef HAVE_PUTUTXLINE
utx.ut_type = NEW_TIME;
utx.ut_tv = timetv;
(void)strcpy(utx.ut_line, NTIME_MSG);
# ifdef HAVE_UPDWTMPX
updwtmpx(WTMPX_FILE, &utx);
# else /* not HAVE_UPDWTMPX */
# endif /* not HAVE_UPDWTMPX */
# else /* not HAVE_PUTUTXLINE */
# endif /* not HAVE_PUTUTXLINE */
#endif /* UPDATE_WTMPX */
}
return (1);
}