Initial checkin

daemonize.c

@@ -0,0 +1,129 @@
+/* $Id$ */
+/* 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 || (strlen(fname) == 0))
+		return -1;
+	
+	if( (pidfile = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0666)) < 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 || (strlen(fname) == 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;
+}
+