/* $OpenBSD: watchdogd.c,v 1.6 2006/01/17 11:38:50 mbalmer Exp $ */ /* * Copyright (c) 2005 Marc Balmer * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include #include #include #include #include #include #include #include volatile sig_atomic_t quit = 0; __dead void usage(void); void sighdlr(int); int main(int, char *[]); __dead void usage(void) { extern char *__progname; fprintf(stderr, "usage: %s [-d] [-i interval] [-p period]\n", __progname); exit(1); } void sighdlr(int signum) { quit = 1; } int main(int argc, char *argv[]) { const char *errstr; size_t len; u_int interval, period, nperiod; int ch, trigauto, sauto, speriod; int daemonize, retval; int mib[3]; interval = 0; period = 30; daemonize = 1; retval = 1; while ((ch = getopt(argc, argv, "di:p:")) != -1) { switch (ch) { case 'd': daemonize = 0; break; case 'i': interval = (int)strtonum(optarg, 1LL, 86400LL, &errstr); if (errstr) errx(1, "interval is %s: %s", errstr, optarg); break; case 'p': period = (int)strtonum(optarg, 2LL, 86400LL, &errstr); if (errstr) errx(1, "period is %s: %s", errstr, optarg); break; default: usage(); /* NOTREACHED */ } } if (interval == 0 && (interval = period / 3) == 0) interval = 1; if (period <= interval) errx(1, "retrigger interval too long"); /* save kern.watchdog.period and kern.watchdog.auto for restore */ mib[0] = CTL_KERN; mib[1] = KERN_WATCHDOG; mib[2] = KERN_WATCHDOG_PERIOD; len = sizeof(speriod); if (sysctl(mib, 3, &speriod, &len, &period, sizeof(period)) == -1) { if (errno == EOPNOTSUPP) errx(1, "no watchdog timer available"); else err(1, "can't access kern.watchdog.period"); } mib[2] = KERN_WATCHDOG_AUTO; len = sizeof(sauto); trigauto = 0; if (sysctl(mib, 3, &sauto, &len, &trigauto, sizeof(trigauto)) == -1) err(1, "can't access kern.watchdog.auto"); /* Double check the timeout period, some devices change the value */ mib[2] = KERN_WATCHDOG_PERIOD; len = sizeof(nperiod); if (sysctl(mib, 3, &nperiod, &len, NULL, 0) == -1) { warnx("can't read back kern.watchdog.period, " "restoring original values"); goto restore; } if (nperiod != period) warnx("period adjusted to %d by device", nperiod); if (nperiod <= interval) { warnx("retrigger interval %d too long, " "restoring original values", interval); goto restore; } if (daemonize && daemon(0, 0)) { warn("can't daemonize, restoring original values"); goto restore; } (void)mlockall(MCL_CURRENT | MCL_FUTURE); setpriority(PRIO_PROCESS, getpid(), -5); signal(SIGTERM, sighdlr); retval = 0; while (!quit) { if (sysctl(mib, 3, NULL, 0, &period, sizeof(period)) == -1) quit = retval = 1; sleep(interval); } restore: sysctl(mib, 3, NULL, 0, &speriod, sizeof(speriod)); mib[2] = KERN_WATCHDOG_AUTO; sysctl(mib, 3, NULL, 0, &sauto, sizeof(sauto)); return (retval); }