dirname.c revision 124208 
1/*      $OpenBSD: dirname.c,v 1.10 2003/06/17 21:56:23 millert Exp $    */
2
3/*
4 * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19#include "includes.h"
20#ifndef HAVE_DIRNAME
21
22#ifndef lint
23static char rcsid[] = "$OpenBSD: dirname.c,v 1.10 2003/06/17 21:56:23 millert Exp $";
24#endif /* not lint */
25
26#include <errno.h>
27#include <string.h>
28#include <sys/param.h>
29
30char *
31dirname(const char *path)
32{
33	static char bname[MAXPATHLEN];
34	register const char *endp;
35
36	/* Empty or NULL string gets treated as "." */
37	if (path == NULL || *path == '\0') {
38		(void)strlcpy(bname, ".", sizeof bname);
39		return(bname);
40	}
41
42	/* Strip trailing slashes */
43	endp = path + strlen(path) - 1;
44	while (endp > path && *endp == '/')
45		endp--;
46
47	/* Find the start of the dir */
48	while (endp > path && *endp != '/')
49		endp--;
50
51	/* Either the dir is "/" or there are no slashes */
52	if (endp == path) {
53		(void)strlcpy(bname, *endp == '/' ? "/" : ".", sizeof bname);
54		return(bname);
55	} else {
56		do {
57			endp--;
58		} while (endp > path && *endp == '/');
59	}
60
61	if (endp - path + 2 > sizeof(bname)) {
62		errno = ENAMETOOLONG;
63		return(NULL);
64	}
65	strlcpy(bname, path, endp - path + 2);
66	return(bname);
67}
68#endif
69