meillo@0: /*  MasqMail
meillo@0:     Copyright (C) 2001 Oliver Kurth
meillo@0: 
meillo@0:     This program is free software; you can redistribute it and/or modify
meillo@0:     it under the terms of the GNU General Public License as published by
meillo@0:     the Free Software Foundation; either version 2 of the License, or
meillo@0:     (at your option) any later version.
meillo@0: 
meillo@0:     This program is distributed in the hope that it will be useful,
meillo@0:     but WITHOUT ANY WARRANTY; without even the implied warranty of
meillo@0:     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
meillo@0:     GNU General Public License for more details.
meillo@0: 
meillo@0:     You should have received a copy of the GNU General Public License
meillo@0:     along with this program; if not, write to the Free Software
meillo@0:     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
meillo@0: */
meillo@0: 
meillo@0: #include <glib.h>
meillo@0: #include <unistd.h>
meillo@0: #include <fcntl.h>
meillo@0: #include <sys/stat.h>
meillo@0: #include <sys/types.h>
meillo@0: #include <syslog.h>
meillo@0: #include <errno.h>
meillo@0: #include <string.h>
meillo@0: #include <time.h>
meillo@0: 
meillo@0: #include "masqmail.h"
meillo@0: #include "dotlock.h"
meillo@0: 
meillo@10: gboolean
meillo@10: dot_lock(gchar * lock_name, gchar * hitch_name)
meillo@0: {
meillo@10: 	gboolean ok = FALSE;
meillo@10: 	int fd;
meillo@0: 
meillo@10: 	fd = open(hitch_name, O_WRONLY | O_CREAT | O_EXCL, 0);
meillo@10: 	if (fd != -1) {
meillo@10: 		struct stat stat_buf;
meillo@0: 
meillo@10: 		close(fd);
meillo@10: 		link(hitch_name, lock_name);
meillo@10: 		if (stat(hitch_name, &stat_buf) == 0) {
meillo@10: 			if (stat_buf.st_nlink == 2) {
meillo@10: 				unlink(hitch_name);
meillo@10: 				ok = TRUE;
meillo@10: 			} else {
meillo@10: 				if (stat(lock_name, &stat_buf) == 0) {
meillo@10: 					if ((time(NULL) - stat_buf.st_mtime) > MAX_LOCKAGE) {
meillo@10: 						/* remove lock if uncredibly old */
meillo@10: 						unlink(lock_name);
meillo@0: 
meillo@10: 						link(hitch_name, lock_name);
meillo@10: 						if (stat(hitch_name, &stat_buf) == 0) {
meillo@10: 							if (stat_buf.st_nlink == 2) {
meillo@10: 								unlink(hitch_name);
meillo@10: 								ok = TRUE;
meillo@10: 							}
meillo@10: 						}
meillo@10: 					}
meillo@10: 				}
meillo@10: 			}
meillo@10: 		}
meillo@10: 		if (!ok) {
meillo@10: 			unlink(hitch_name);
meillo@10: 		}
meillo@10: 	} else
meillo@10: 		logwrite(LOG_WARNING, "could not create lock file %s: %s\n", lock_name, strerror(errno));
meillo@0: 
meillo@10: 	return ok;
meillo@0: }
meillo@0: 
meillo@10: gboolean
meillo@10: dot_unlock(gchar * lock_name)
meillo@0: {
meillo@10: 	unlink(lock_name);
meillo@0: 
meillo@10: 	return TRUE;
meillo@0: }