1/*	$OpenBSD: dirname.c,v 1.13 2005/08/08 08:05:33 espie Exp $	*/
2
3/*
4 * Copyright (c) 1997, 2004 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/* OPENBSD ORIGINAL: lib/libc/gen/dirname.c */
20
21#include "includes.h"
22#ifndef HAVE_DIRNAME
23
24#include <errno.h>
25#include <string.h>
26
27char *
28dirname(const char *path)
29{
30	static char dname[MAXPATHLEN];
31	size_t len;
32	const char *endp;
33
34	/* Empty or NULL string gets treated as "." */
35	if (path == NULL || *path == '\0') {
36		dname[0] = '.';
37		dname[1] = '\0';
38		return (dname);
39	}
40
41	/* Strip any trailing slashes */
42	endp = path + strlen(path) - 1;
43	while (endp > path && *endp == '/')
44		endp--;
45
46	/* Find the start of the dir */
47	while (endp > path && *endp != '/')
48		endp--;
49
50	/* Either the dir is "/" or there are no slashes */
51	if (endp == path) {
52		dname[0] = *endp == '/' ? '/' : '.';
53		dname[1] = '\0';
54		return (dname);
55	} else {
56		/* Move forward past the separating slashes */
57		do {
58			endp--;
59		} while (endp > path && *endp == '/');
60	}
61
62	len = endp - path + 1;
63	if (len >= sizeof(dname)) {
64		errno = ENAMETOOLONG;
65		return (NULL);
66	}
67	memcpy(dname, path, len);
68	dname[len] = '\0';
69	return (dname);
70}
71#endif
72