xref: /freebsd/contrib/mandoc/compat_mkdtemp.c (revision 0957b409)
1 #include "config.h"
2 
3 #if HAVE_MKDTEMP
4 
5 int dummy;
6 
7 #else
8 
9 /*	$Id: compat_mkdtemp.c,v 1.2 2015/10/06 18:32:19 schwarze Exp $	*/
10 /*
11  * Copyright (c) 2015 Ingo Schwarze <schwarze@openbsd.org>
12  *
13  * Permission to use, copy, modify, and distribute this software for any
14  * purpose with or without fee is hereby granted, provided that the above
15  * copyright notice and this permission notice appear in all copies.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
18  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
20  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
21  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
22  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
23  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
24  *
25  * The algorithm of this function is inspired by OpenBSD mkdtemp(3)
26  * by Theo de Raadt and Todd Miller, but the code differs.
27  */
28 
29 #include <sys/stat.h>
30 #include <errno.h>
31 #include <limits.h>
32 #include <stdlib.h>
33 #include <string.h>
34 
35 char *
36 mkdtemp(char *path)
37 {
38 	char		*start, *cp;
39 	unsigned	 int tries;
40 
41 	start = strchr(path, '\0');
42 	while (start > path && start[-1] == 'X')
43 		start--;
44 
45 	for (tries = INT_MAX; tries; tries--) {
46 		if (mktemp(path) == NULL) {
47 			errno = EEXIST;
48 			return NULL;
49 		}
50 		if (mkdir(path, S_IRUSR | S_IWUSR | S_IXUSR) == 0)
51 			return path;
52 		if (errno != EEXIST)
53 			return NULL;
54 		for (cp = start; *cp != '\0'; cp++)
55 			*cp = 'X';
56 	}
57 	errno = EEXIST;
58 	return NULL;
59 }
60 
61 #endif
62