xref: /titanic_41/usr/src/lib/libast/common/comp/basename.c (revision 15d9d0b528387242011cdcc6190c9e598cfe3a07)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *           Copyright (c) 1985-2007 AT&T Knowledge Ventures            *
5 *                      and is licensed under the                       *
6 *                  Common Public License, Version 1.0                  *
7 *                      by AT&T Knowledge Ventures                      *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                  David Korn <dgk@research.att.com>                   *
19 *                   Phong Vo <kpv@research.att.com>                    *
20 *                                                                      *
21 ***********************************************************************/
22 #pragma prototyped
23 /*
24  * basename(3) implementation
25  */
26 
27 #include <ast_std.h>
28 
29 #if defined(__EXPORT__)
30 #define extern	__EXPORT__
31 #endif
32 
33 extern char *basename(register char *pathname)
34 {
35 	register char *first, *last;
36 	for(first=last=pathname; *last; last++);
37 	/* back over trailing '/' */
38 	if(last>first)
39 		while(*--last=='/' && last > first);
40 	if(last==first && *last=='/')
41 	{
42 		/* all '/' or "" */
43 		if(*first=='/')
44 			if(*++last=='/')	/* keep leading // */
45 				last++;
46 	}
47 	else
48 	{
49 		for(first=last++;first>pathname && *first!='/';first--);
50 		if(*first=='/')
51 			first++;
52 	}
53 	*last = 0;
54 	return(first);
55 }
56