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/* $Id: daemon.c,v 0.2 1997/08/30 17:59:36 yoichi v0_70 $
*
* dhcpcd - DHCP client daemon -
* Copyright (C) 1996 - 1997 Yoichi Hariguchi <yoichi@fore.com>
*
* Dhcpcd is an RFC2131 and RFC1541 compliant DHCP client daemon.
*
* This 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "error-handler.h"
#include "daemon.h"
#ifdef OPEN_MAX
static int OpenMax = OPEN_MAX;
#else
static int OpenMax = 0;
#endif
#define OPEN_MAX_GUESS 256
void
daemonInit(const char *pidfile)
{
char s[10];
pid_t pid;
int fd;
int i;
if ( (pid = fork() ) < 0 ) {
errSysExit("fork (daemonInit)");
} else if ( pid != 0 ) {
/* parent saves pid into *pidfile, and goes bye-bye
*/
if ( pidfile != NULL ) {
if ( (fd = creat(pidfile,
S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)) < 0 ) {
logSysRet("creat (daemonInit)");
return;
}
sprintf(s, "%d\n", pid);
if ( write(fd, s, strlen(s)) < 0 ) {
logSysRet("write (daemonInit)");
}
close(fd);
}
exit(0);
}
/* child continues
*/
setsid();
chdir("/");
umask(0);
for ( i = 0; i < openMax(); ++i ) {
close(i);
}
}
int
openMax()
{
if ( OpenMax == 0 ) {
errno = 0;
if ( (OpenMax = sysconf(_SC_OPEN_MAX)) < 0 ) {
if ( errno == 0 ) {
OpenMax = OPEN_MAX_GUESS; /* it's indeterminate */
} else {
errSysExit("sysconf (openMax)");
}
}
}
return OpenMax;
}
void
killCurProc(char *pidfile)
{
int fd;
int len;
int pid;
char pidStr[8];
if ( (fd = open(pidfile, O_RDONLY)) < 0 ) {
errSysExit("open (killCurProc) %s", pidfile);
}
if ( (len = read(fd, pidStr, 8)) < 0 ) {
errSysExit("read (killCurProc)");
}
pidStr[len] = '\0';
pid = atoi(pidStr);
if ( kill(pid, SIGTERM) < 0 ) {
if ( unlink(pidfile) < 0 ) {
errSysRet("unlink (killCurProc)");
}
errSysExit("kill (killCurProc) pid %d", pid);
}
errMsg("Process (pid %d) has been successfully terminated", pid);
if ( unlink(pidfile) < 0 ) {
errSysExit("unlink (killCurProc)");
}
exit(0);
}
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