Permalink
Find file
Fetching contributors…
Cannot retrieve contributors at this time
204 lines (143 sloc) 3.92 KB
/*
* Copyright (C) 2011 Tildeslash Ltd. All rights reserved.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 3.
*
* 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, see <http://www.gnu.org/licenses/>.
*
* In addition, as a special exception, the copyright holders give
* permission to link the code of portions of this program with the
* OpenSSL library under certain conditions as described in each
* individual source file, and distribute linked combinations
* including the two.
*
* You must obey the GNU General Public License in all respects
* for all of the code used other than OpenSSL. If you modify
* file(s) with this exception, you may extend this exception to your
* version of the file(s), but you are not obligated to do so. If you
* do not wish to do so, delete this exception statement from your
* version. If you delete this exception statement from all source
* files in the program, then also delete it here.
*/
#include <config.h>
#ifdef HAVE_STDIO_H
#include <stdio.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_SIGNAL_H
#include <signal.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include "monitor.h"
/**
* Transform this program into a daemon and provide methods for
* managing the daemon.
*
* @author Jan-Henrik Haukeland, <hauk@tildeslash.com>
*
* @file
*/
/* ------------------------------------------------------------------ Public */
/**
* Transform a program into a daemon. Inspired by code from Stephen
* A. Rago's book, Unix System V Network Programming.
*/
void daemonize() {
pid_t pid;
/*
* Clear file creation mask
*/
umask(0);
/*
* Become a session leader to lose our controlling terminal
*/
if((pid= fork ()) < 0) {
LogError("Cannot fork of a new process\n");
exit (1);
}
else if(pid != 0) {
_exit(0);
}
setsid();
if((pid= fork ()) < 0) {
LogError("Cannot fork of a new process\n");
exit (1);
}
else if(pid != 0) {
_exit(0);
}
/*
* Change current directory to the root so that other file systems
* can be unmounted while we're running
*/
if(chdir("/") < 0) {
LogError("Cannot chdir to / -- %s\n", STRERROR);
exit(1);
}
/*
* Attach standard descriptors to /dev/null. Other descriptors
* should be closed in env.c
*/
Util_redirectStdFds();
}
/**
* Send signal to a daemon process
* @param sig Signal to send daemon to
* @return TRUE if signal was send, otherwise FALSE
*/
int kill_daemon(int sig) {
pid_t pid;
if ( (pid= exist_daemon()) > 0 ) {
if ( kill(pid, sig) < 0 ) {
LogError("%s: Cannot send signal to daemon process -- %s\n",
prog, STRERROR);
return FALSE;
}
} else {
LogInfo("%s: No daemon process found\n", prog);
return TRUE;
}
if(sig == SIGTERM) {
fprintf(stdout, "%s daemon with pid [%d] killed\n", prog, (int)pid);
fflush(stdout);
}
return TRUE;
}
/**
* @return TRUE (i.e. the daemons pid) if a daemon process is running,
* otherwise FALSE
*/
int exist_daemon() {
pid_t pid;
errno= 0;
if( (pid= Util_getPid(Run.pidfile)) )
if( (getpgid(pid)) > -1 || (errno == EPERM) )
return( (int)pid );
return(FALSE);
}