xref: /netbsd-src/usr.bin/basename/basename.c (revision 1c9b56c830954ccf3b57004ac65562e3d6afacf6)
1 /*	$NetBSD: basename.c,v 1.12 2005/02/17 16:57:27 xtraeme Exp $	*/
2 
3 /*-
4  * Copyright (c) 1991, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1991, 1993, 1994\n\
35 	The Regents of the University of California.  All rights reserved.\n");
36 #endif /* not lint */
37 
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)basename.c	8.4 (Berkeley) 5/4/95";
41 #endif
42 __RCSID("$NetBSD: basename.c,v 1.12 2005/02/17 16:57:27 xtraeme Exp $");
43 #endif /* not lint */
44 
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <locale.h>
49 #include <unistd.h>
50 
51 void usage(void);
52 
53 int
54 main(int argc, char **argv)
55 {
56 	char *p;
57 	int ch;
58 
59 	setlocale(LC_ALL, "");
60 
61 	while ((ch = getopt(argc, argv, "")) != -1)
62 		switch(ch) {
63 		case '?':
64 		default:
65 			usage();
66 		}
67 	argc -= optind;
68 	argv += optind;
69 
70 	if (argc != 1 && argc != 2)
71 		usage();
72 
73 	/*
74 	 * (1) If string is // it is implementation defined whether steps (2)
75 	 *     through (5) are skipped or processed.
76 	 *
77 	 * (2) If string consists entirely of slash characters, string shall
78 	 *     be set to a single slash character.  In this case, skip steps
79 	 *     (3) through (5).
80 	 */
81 	for (p = *argv;; ++p) {
82 		if (!*p) {
83 			if (p > *argv)
84 				(void)printf("/\n");
85 			else
86 				(void)printf("\n");
87 			exit(0);
88 		}
89 		if (*p != '/')
90 			break;
91 	}
92 
93 	/*
94 	 * (3) If there are any trailing slash characters in string, they
95 	 *     shall be removed.
96 	 */
97 	for (; *p; ++p)
98 		continue;
99 	while (*--p == '/')
100 		continue;
101 	*++p = '\0';
102 
103 	/*
104 	 * (4) If there are any slash characters remaining in string, the
105 	 *     prefix of string up to an including the last slash character
106 	 *     in string shall be removed.
107 	 */
108 	while (--p >= *argv)
109 		if (*p == '/')
110 			break;
111 	++p;
112 
113 	/*
114 	 * (5) If the suffix operand is present, is not identical to the
115 	 *     characters remaining in string, and is identical to a suffix
116 	 *     of the characters remaining in string, the suffix suffix
117 	 *     shall be removed from string.
118 	 */
119 	if (*++argv) {
120 		int suffixlen, stringlen, off;
121 
122 		suffixlen = strlen(*argv);
123 		stringlen = strlen(p);
124 
125 		if (suffixlen < stringlen) {
126 			off = stringlen - suffixlen;
127 			if (!strcmp(p + off, *argv))
128 				p[off] = '\0';
129 		}
130 	}
131 	(void)printf("%s\n", p);
132 	exit(0);
133 }
134 
135 void
136 usage(void)
137 {
138 
139 	(void)fprintf(stderr, "usage: basename string [suffix]\n");
140 	exit(1);
141 }
142