/*
* Used for handling errors that occur before we daemonize.
*/
static void
early_error(const char *str)
{
const char *cp;
cp = mystrerror(errno);
if (isatty(2)) {
(void) fprintf(stderr, "%s: %s: %s\n", myname, str, cp);
} else {
reopen_log();
logerr("%s: %s", str, cp);
}
exit(1);
}
/*
* Become a daemon.
*/
static void
daemonize(void)
{
pid_t cpid;
/*
* A little bit of magic here. By the first fork+setsid, we
* disconnect from our current controlling terminal and become
* a session group leader. By forking again without setsid,
* we make certain that we're not the session group leader and
* can never reacquire a controlling terminal.
*/
if ((cpid = fork()) == (pid_t)-1) {
early_error("fork 1");
}
if (cpid != 0) {
(void) wait(NULL);
_exit(0);
}
if (setsid() == (pid_t)-1) {
early_error("setsid");
}
if ((cpid = fork()) == (pid_t)-1) {
early_error("fork 2");
}
if (cpid != 0) {
/* Parent just exits */
(void) printf("%d\n", (int)cpid);
(void) fflush(stdout);
_exit(0);
}
(void) chdir("/");
(void) umask(0);
(void) fdwalk(fdcloser, NULL);
reopen_log();
}
int main(int argc, char **argv)
{
int interval = 30, i;
const char *prog = xbasename(argv[0]);
time_t now, nextpoll = 0;
const char *user = NULL;
struct passwd *new_uid = NULL;
const char *pidfilebase = prog;
logformat = DEFAULT_LOGFORMAT;
user = RUN_AS_USER;
printf("Network UPS Tools %s %s\n", prog, UPS_VERSION);
while ((i = getopt(argc, argv, "+hs:l:i:f:u:Vp:")) != -1) {
switch(i) {
case 'h':
help(prog);
break;
case 's':
monhost = optarg;
break;
case 'l':
logfn = optarg;
break;
case 'i':
interval = atoi(optarg);
break;
case 'f':
logformat = optarg;
break;
case 'u':
user = optarg;
break;
case 'V':
exit(EXIT_SUCCESS);
case 'p':
pidfilebase = optarg;
break;
}
}
argc -= optind;
argv += optind;
/* not enough args for the old way? */
if ((argc == 1) || (argc == 2))
help(prog);
/* see if it's being called in the old style - 3 or 4 args */
/* <system> <logfn> <interval> [<format>] */
if (argc >= 3) {
monhost = argv[0];
logfn = argv[1];
interval = atoi(argv[2]);
}
if (argc >= 4) {
/* read out the remaining argv entries to the format string */
logformat = xmalloc(LARGEBUF);
memset(logformat, '\0', LARGEBUF);
for (i = 3; i < argc; i++)
snprintfcat(logformat, LARGEBUF, "%s ", argv[i]);
}
if (!monhost)
fatalx(EXIT_FAILURE, "No UPS defined for monitoring - use -s <system>");
if (!logfn)
fatalx(EXIT_FAILURE, "No filename defined for logging - use -l <file>");
/* shouldn't happen */
if (!logformat)
fatalx(EXIT_FAILURE, "No format defined - but this should be impossible");
printf("logging status of %s to %s (%is intervals)\n",
monhost, logfn, interval);
if (upscli_splitname(monhost, &upsname, &hostname, &port) != 0) {
fatalx(EXIT_FAILURE, "Error: invalid UPS definition. Required format: upsname[@hostname[:port]]\n");
}
if (upscli_connect(&ups, hostname, port, UPSCLI_CONN_TRYSSL) < 0)
fprintf(stderr, "Warning: initial connect failed: %s\n",
upscli_strerror(&ups));
if (strcmp(logfn, "-") == 0)
logfile = stdout;
else
logfile = fopen(logfn, "a");
if (logfile == NULL)
fatal_with_errno(EXIT_FAILURE, "could not open logfile %s", logfn);
/* now drop root if we have it */
new_uid = get_user_pwent(user);
open_syslog(prog);
if (logfile != stdout)
background();
setup_signals();
writepid(pidfilebase);
become_user(new_uid);
compile_format();
while (exit_flag == 0) {
time(&now);
if (nextpoll > now) {
/* there is still time left, so sleep it off */
sleep(difftime(nextpoll, now));
nextpoll += interval;
} else {
/* we spent more time in polling than the interval allows */
nextpoll = now + interval;
}
if (reopen_flag) {
upslogx(LOG_INFO, "Signal %d: reopening log file",
reopen_flag);
reopen_log();
reopen_flag = 0;
}
/* reconnect if necessary */
if (upscli_fd(&ups) < 0) {
upscli_connect(&ups, hostname, port, 0);
}
run_flist();
/* don't keep connection open if we don't intend to use it shortly */
if (interval > 30) {
upscli_disconnect(&ups);
}
}
upslogx(LOG_INFO, "Signal %d: exiting", exit_flag);
if (logfile != stdout)
fclose(logfile);
upscli_disconnect(&ups);
exit(EXIT_SUCCESS);
}
