miniupnpc/miniupnpd/daemonize.c
2018-04-20 17:19:52 +02:00

130 lines
2.1 KiB
C

/* $Id: daemonize.c,v 1.12 2011/05/27 09:35:02 nanard Exp $ */
/* MiniUPnP project
* http://miniupnp.free.fr/ or http://miniupnp.tuxfamily.org/
* (c) 2006 Thomas Bernard
* This software is subject to the conditions detailed
* in the LICENCE file provided within the distribution */
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <syslog.h>
#include <string.h>
#include <signal.h>
#include "daemonize.h"
#include "config.h"
#ifndef USE_DAEMON
int
daemonize(void)
{
int pid, i;
switch(fork())
{
/* fork error */
case -1:
perror("fork()");
exit(1);
/* child process */
case 0:
/* obtain a new process group */
if( (pid = setsid()) < 0)
{
perror("setsid()");
exit(1);
}
/* close all descriptors */
for (i=getdtablesize();i>=0;--i) close(i);
i = open("/dev/null", O_RDWR); /* open stdin */
dup(i); /* stdout */
dup(i); /* stderr */
umask(027);
chdir("/"); /* chdir to /tmp ? */
return pid;
/* parent process */
default:
exit(0);
}
}
#endif
int
writepidfile(const char * fname, int pid)
{
char pidstring[16];
int pidstringlen;
int pidfile;
if(!fname || fname[0] == '\0')
return -1;
if( (pidfile = open(fname, O_WRONLY|O_CREAT, 0644)) < 0)
{
syslog(LOG_ERR, "Unable to open pidfile for writing %s: %m", fname);
return -1;
}
pidstringlen = snprintf(pidstring, sizeof(pidstring), "%d\n", pid);
if(pidstringlen <= 0)
{
syslog(LOG_ERR,
"Unable to write to pidfile %s: snprintf(): FAILED", fname);
close(pidfile);
return -1;
}
else
{
if(write(pidfile, pidstring, pidstringlen) < 0)
syslog(LOG_ERR, "Unable to write to pidfile %s: %m", fname);
}
close(pidfile);
return 0;
}
int
checkforrunning(const char * fname)
{
char buffer[64];
int pidfile;
pid_t pid;
if(!fname || fname[0] == '\0')
return -1;
if( (pidfile = open(fname, O_RDONLY)) < 0)
return 0;
memset(buffer, 0, 64);
if(read(pidfile, buffer, 63))
{
if( (pid = atol(buffer)) > 0)
{
if(!kill(pid, 0))
{
close(pidfile);
return -2;
}
}
}
close(pidfile);
return 0;
}