dirname.c revision 126274 
1/* OPENBSD ORIGINAL: lib/libc/gen/dirname.c */
2
3/*      $OpenBSD: dirname.c,v 1.10 2003/06/17 21:56:23 millert Exp $    */
4
5/*
6 * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
7 *
8 * Permission to use, copy, modify, and distribute this software for any
9 * purpose with or without fee is hereby granted, provided that the above
10 * copyright notice and this permission notice appear in all copies.
11 *
12 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 */
20
21#include "includes.h"
22#ifndef HAVE_DIRNAME
23
24#ifndef lint
25static char rcsid[] = "$OpenBSD: dirname.c,v 1.10 2003/06/17 21:56:23 millert Exp $";
26#endif /* not lint */
27
28#include <errno.h>
29#include <string.h>
30#include <sys/param.h>
31
32char *
33dirname(const char *path)
34{
35	static char bname[MAXPATHLEN];
36	register const char *endp;
37
38	/* Empty or NULL string gets treated as "." */
39	if (path == NULL || *path == '\0') {
40		(void)strlcpy(bname, ".", sizeof bname);
41		return(bname);
42	}
43
44	/* Strip trailing slashes */
45	endp = path + strlen(path) - 1;
46	while (endp > path && *endp == '/')
47		endp--;
48
49	/* Find the start of the dir */
50	while (endp > path && *endp != '/')
51		endp--;
52
53	/* Either the dir is "/" or there are no slashes */
54	if (endp == path) {
55		(void)strlcpy(bname, *endp == '/' ? "/" : ".", sizeof bname);
56		return(bname);
57	} else {
58		do {
59			endp--;
60		} while (endp > path && *endp == '/');
61	}
62
63	if (endp - path + 2 > sizeof(bname)) {
64		errno = ENAMETOOLONG;
65		return(NULL);
66	}
67	strlcpy(bname, path, endp - path + 2);
68	return(bname);
69}
70#endif
71