xref: /freebsd/crypto/openssh/openbsd-compat/basename.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
1 /*	$OpenBSD: basename.c,v 1.14 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/basename.c */
20 
21 #include "includes.h"
22 #ifndef HAVE_BASENAME
23 #include <errno.h>
24 #include <string.h>
25 
26 char *
27 basename(const char *path)
28 {
29 	static char bname[MAXPATHLEN];
30 	size_t len;
31 	const char *endp, *startp;
32 
33 	/* Empty or NULL string gets treated as "." */
34 	if (path == NULL || *path == '\0') {
35 		bname[0] = '.';
36 		bname[1] = '\0';
37 		return (bname);
38 	}
39 
40 	/* Strip any trailing slashes */
41 	endp = path + strlen(path) - 1;
42 	while (endp > path && *endp == '/')
43 		endp--;
44 
45 	/* All slashes becomes "/" */
46 	if (endp == path && *endp == '/') {
47 		bname[0] = '/';
48 		bname[1] = '\0';
49 		return (bname);
50 	}
51 
52 	/* Find the start of the base */
53 	startp = endp;
54 	while (startp > path && *(startp - 1) != '/')
55 		startp--;
56 
57 	len = endp - startp + 1;
58 	if (len >= sizeof(bname)) {
59 		errno = ENAMETOOLONG;
60 		return (NULL);
61 	}
62 	memcpy(bname, startp, len);
63 	bname[len] = '\0';
64 	return (bname);
65 }
66 
67 #endif /* !defined(HAVE_BASENAME) */
68