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/* vi: set sw=4 ts=4: */
/*
* Mini update implementation for busybox; much pasted from update-2.11
*
*
* Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
* Copyright (c) 1996, 1997, 1999 Torsten Poulin.
* Copyright (c) 2000 by Karl M. Hegbloom <karlheg@debian.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include "internal.h"
#include <linux/unistd.h>
#include <sys/param.h>
#include <sys/syslog.h>
#if defined(__GLIBC__)
#include <sys/kdaemon.h>
#else
_syscall2(int, bdflush, int, func, int, data);
#endif /* __GLIBC__ */
static char update_usage[] =
"update [options]\n"
#ifndef BB_FEATURE_TRIVIAL_HELP
"\nPeriodically flushes filesystem buffers.\n\n"
"Options:\n"
"\t-S\tforce use of sync(2) instead of flushing\n"
"\t-s SECS\tcall sync this often (default 30)\n"
"\t-f SECS\tflush some buffers this often (default 5)\n"
#endif
;
static unsigned int sync_duration = 30;
static unsigned int flush_duration = 5;
static int use_sync = 0;
extern int update_main(int argc, char **argv)
{
int pid;
argc--;
argv++;
while (argc>0 && **argv == '-') {
while (*++(*argv)) {
switch (**argv) {
case 'S':
use_sync = 1;
break;
case 's':
if (--argc < 1) usage(update_usage);
sync_duration = atoi(*(++argv));
break;
case 'f':
if (--argc < 1) usage(update_usage);
flush_duration = atoi(*(++argv));
break;
default:
usage(update_usage);
}
}
argc--;
argv++;
}
pid = fork();
if (pid < 0)
exit(FALSE);
else if (pid == 0) {
/* Become a proper daemon */
setsid();
chdir("/");
for (pid = 0; pid < OPEN_MAX; pid++) close(pid);
/*
* This is no longer necessary since 1.3.5x, but it will harmlessly
* exit if that is the case.
*/
argv[0] = "bdflush (update)";
argv[1] = NULL;
argv[2] = NULL;
for (;;) {
if (use_sync) {
sleep(sync_duration);
sync();
} else {
sleep(flush_duration);
if (bdflush(1, 0) < 0) {
openlog("update", LOG_CONS, LOG_DAEMON);
syslog(LOG_INFO,
"This kernel does not need update(8). Exiting.");
closelog();
exit(TRUE);
}
}
}
}
exit( TRUE);
}
/*
Local Variables:
c-file-style: "linux"
c-basic-offset: 4
tab-width: 4
End:
*/
|
