1
/*************************************************************************/
2
/* (c) Copyright Tai Jin, 1988. All Rights Reserved. */
3
/* Hewlett-Packard Laboratories. */
5
/* Permission is hereby granted for unlimited modification, use, and */
6
/* distribution. This software is made available with no warranty of */
7
/* any kind, express or implied. This copyright notice must remain */
8
/* intact in all versions of this software. */
10
/* The author would appreciate it if any bug fixes and enhancements were */
11
/* to be sent back to him for incorporation into future versions of this */
12
/* software. Please send changes to tai@iag.hp.com or ken@sdd.hp.com. */
13
/*************************************************************************/
16
static char RCSid[] = "adjtimed.c,v 3.1 1993/07/06 01:04:45 jbj Exp";
21
* This daemon adjusts the rate of the system clock a la BSD's adjtime().
22
* The adjtime() routine uses SYSV messages to communicate with this daemon.
24
* Caveat: This emulation uses an undocumented kernel variable. As such, it
25
* cannot be guaranteed to work in future HP-UX releases. Fortunately,
26
* it will no longer be needed in HPUX 10.01 and later.
29
#include <sys/param.h>
30
#include <sys/types.h>
41
#include "ntp_syslog.h"
42
#include "ntp_stdlib.h"
46
double atof (const char *);
48
int InitClockRate (void);
49
int AdjustClockRate (register struct timeval *delta, register struct timeval *olddelta);
50
long GetClockRate (void);
51
int SetClockRate (long);
52
void ResetClockRate (void);
56
#define MILLION 1000000L
58
/* emacs cc-mode goes nuts if we split the next line... */
59
#define tvtod(tv) ((double)tv.tv_sec + ((double)tv.tv_usec / (double)MILLION))
61
char *progname = NULL;
65
static double oldrate = 0.0;
73
struct timeval remains;
83
openlog("adjtimed", LOG_PID, LOG_LOCAL6);
85
openlog("adjtimed", LOG_PID);
88
while ((ch = ntp_getopt(argc, argv, "hkrvdfp:")) != EOF) {
92
if ((mqid = msgget(KEY, 0)) != -1) {
93
if (msgctl(mqid, IPC_RMID, (struct msqid_ds *)0) == -1) {
94
msyslog(LOG_ERR, "remove old message queue: %m");
95
perror("adjtimed: remove old message queue");
106
++verbose, nofork = 1;
118
fputs("adjtimed: -p option ignored\n", stderr);
122
puts("usage: adjtimed -hkrvdf");
124
puts("-k\tkill existing adjtimed, if any");
125
puts("-r\trestart (kills existing adjtimed, if any)");
126
puts("-v\tdebug output (repeat for more output)");
127
puts("-d\tsyslog output (repeat for more output)");
129
msyslog(LOG_ERR, "usage error");
137
close(fileno(stdin));
138
close(fileno(stdout));
139
close(fileno(stderr));
142
if ((fd = open("/dev/tty")) != -1) {
143
ioctl(fd, TIOCNOTTY, 0);
152
msyslog(LOG_ERR, "fork: %m");
153
perror("adjtimed: fork");
162
setvbuf(stdout, NULL, _IONBF, BUFSIZ);
163
setvbuf(stderr, NULL, _IONBF, BUFSIZ);
166
msyslog(LOG_INFO, "started");
167
if (verbose) printf("adjtimed: started\n");
169
if (InitClockRate() == -1)
172
(void)signal(SIGHUP, SIG_IGN);
173
(void)signal(SIGINT, SIG_IGN);
174
(void)signal(SIGQUIT, SIG_IGN);
175
(void)signal(SIGTERM, Cleanup);
177
vec.sv_handler = ResetClockRate;
180
sigvector(SIGALRM, &vec, (struct sigvec *)0);
182
if (msgget(KEY, IPC_CREAT|IPC_EXCL) == -1) {
183
if (errno == EEXIST) {
184
msyslog(LOG_ERR, "message queue already exists, use -r to remove it");
185
fputs("adjtimed: message queue already exists, use -r to remove it\n",
190
msyslog(LOG_ERR, "create message queue: %m");
191
perror("adjtimed: create message queue");
195
if ((mqid = msgget(KEY, 0)) == -1) {
196
msyslog(LOG_ERR, "get message queue id: %m");
197
perror("adjtimed: get message queue id");
201
/* Lock process in memory to improve response time */
202
if (plock(PROCLOCK)) {
203
msyslog(LOG_ERR, "plock: %m");
204
perror("adjtimed: plock");
208
/* Also raise process priority.
209
* If we do not get run when we want, this leads to bad timekeeping
210
* and "Previous time adjustment didn't complete" gripes from xntpd.
212
if (nice(-10) == -1) {
213
msyslog(LOG_ERR, "nice: %m");
214
perror("adjtimed: nice");
219
if (msgrcv(mqid, &msg.msgp, MSGSIZE, CLIENT, 0) == -1) {
220
if (errno == EINTR) continue;
221
msyslog(LOG_ERR, "read message: %m");
222
perror("adjtimed: read message");
226
switch (msg.msgb.code) {
229
AdjustClockRate(&msg.msgb.tv, &remains);
231
if (msg.msgb.code == DELTA2) {
232
msg.msgb.tv = remains;
233
msg.msgb.mtype = SERVER;
235
while (msgsnd(mqid, &msg.msgp, MSGSIZE, 0) == -1) {
236
if (errno == EINTR) continue;
237
msyslog(LOG_ERR, "send message: %m");
238
perror("adjtimed: send message");
243
if (remains.tv_sec + remains.tv_usec != 0L) {
245
printf("adjtimed: previous correction remaining %.6fs\n",
249
msyslog(LOG_INFO, "previous correction remaining %.6fs",
256
fprintf(stderr, "adjtimed: unknown message code %d\n", msg.msgb.code);
257
msyslog(LOG_ERR, "unknown message code %d", msg.msgb.code);
263
* Default clock rate (old_tick).
265
#define DEFAULT_RATE (MILLION / HZ)
266
#define UNKNOWN_RATE 0L
267
#define TICK_ADJ 5 /* standard adjustment rate, microsec/tick */
269
static long default_rate = DEFAULT_RATE;
270
static long tick_rate = HZ; /* ticks per sec */
271
static long slew_rate = TICK_ADJ * HZ; /* in microsec/sec */
275
register struct timeval *delta,
276
register struct timeval *olddelta
279
register long rate, dt, leftover;
280
struct itimerval period, remains;
282
dt = (delta->tv_sec * MILLION) + delta->tv_usec;
285
printf("adjtimed: new correction %.6fs\n", (double)dt / (double)MILLION);
287
msyslog(LOG_INFO, "new correction %.6fs", (double)dt / (double)MILLION);
288
if (verbose > 2) printf("adjtimed: leftover %ldus\n", leftover);
289
if (sysdebug > 2) msyslog(LOG_INFO, "leftover %ldus", leftover);
293
* Apply a slew rate of slew_rate over a period of dt/slew_rate seconds.
301
period.it_value.tv_sec = dt / slew_rate;
302
period.it_value.tv_usec = (dt % slew_rate) * (MILLION / slew_rate);
304
* Note: we assume the kernel will convert the specified period into ticks
305
* using the modified clock rate rather than an assumed nominal clock rate,
306
* and therefore will generate the timer interrupt after the specified
307
* number of true seconds, not skewed seconds.
311
printf("adjtimed: will be complete in %lds %ldus\n",
312
period.it_value.tv_sec, period.it_value.tv_usec);
314
msyslog(LOG_INFO, "will be complete in %lds %ldus",
315
period.it_value.tv_sec, period.it_value.tv_usec);
317
* adjust the clock rate
320
if (SetClockRate((rate / tick_rate) + default_rate) == -1) {
321
msyslog(LOG_ERR, "set clock rate: %m");
322
perror("adjtimed: set clock rate");
327
* (do this after changing the rate because the period has been rounded down)
329
period.it_interval.tv_sec = period.it_interval.tv_usec = 0L;
330
setitimer(ITIMER_REAL, &period, &remains);
335
dt = ((remains.it_value.tv_sec * MILLION) + remains.it_value.tv_usec) *
337
olddelta->tv_sec = dt / MILLION;
338
olddelta->tv_usec = dt - (olddelta->tv_sec * MILLION);
341
oldrate = (double)rate / (double)MILLION;
343
} /* AdjustClockRate */
345
static struct nlist nl[] = {
361
* The return value is the clock rate in old_tick units or -1 if error.
368
if (lseek(kmem, (off_t)nl[0].n_value, 0) == -1L)
371
mask = sigblock(sigmask(SIGALRM));
373
if (read(kmem, (caddr_t)&rate, sizeof(rate)) != sizeof(rate))
381
* The argument is the new rate in old_tick units.
390
if (lseek(kmem, (off_t)nl[0].n_value, 0) == -1L)
393
mask = sigblock(sigmask(SIGALRM));
395
if (write(kmem, (caddr_t)&rate, sizeof(rate)) != sizeof(rate)) {
402
if (rate != default_rate) {
404
printf("adjtimed: clock rate (%lu) %ldus/s\n", rate,
405
(rate - default_rate) * tick_rate);
408
msyslog(LOG_INFO, "clock rate (%lu) %ldus/s", rate,
409
(rate - default_rate) * tick_rate);
419
if ((kmem = open("/dev/kmem", O_RDWR)) == -1) {
420
msyslog(LOG_ERR, "open(/dev/kmem): %m");
421
perror("adjtimed: open(/dev/kmem)");
427
if (nl[0].n_type == 0) {
428
fputs("adjtimed: /hp-ux has no symbol table\n", stderr);
429
msyslog(LOG_ERR, "/hp-ux has no symbol table");
433
* Set the default to the system's original value
435
default_rate = GetClockRate();
436
if (default_rate == UNKNOWN_RATE) default_rate = DEFAULT_RATE;
437
tick_rate = (MILLION / default_rate);
438
slew_rate = TICK_ADJ * tick_rate;
439
fprintf(stderr,"default_rate=%ld, tick_rate=%ld, slew_rate=%ld\n",default_rate,tick_rate,slew_rate);
442
} /* InitClockRate */
445
* Reset the clock rate to the default value.
452
it.it_value.tv_sec = it.it_value.tv_usec = 0L;
453
setitimer(ITIMER_REAL, &it, (struct itimerval *)0);
455
if (verbose > 2) puts("adjtimed: resetting the clock");
456
if (sysdebug > 2) msyslog(LOG_INFO, "resetting the clock");
458
if (GetClockRate() != default_rate) {
459
if (SetClockRate(default_rate) == -1) {
460
msyslog(LOG_ERR, "set clock rate: %m");
461
perror("adjtimed: set clock rate");
466
} /* ResetClockRate */
473
if (msgctl(mqid, IPC_RMID, (struct msqid_ds *)0) == -1) {
474
if (errno != EINVAL) {
475
msyslog(LOG_ERR, "remove message queue: %m");
476
perror("adjtimed: remove message queue");
487
msyslog(LOG_ERR, "terminated");
489
if (kmem != -1) close(kmem);