xref: /netbsd-src/usr.bin/basename/basename.c (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1 /*	$NetBSD: basename.c,v 1.9 1995/09/02 05:29:46 jtc 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 static char copyright[] =
38 "@(#) Copyright (c) 1991, 1993, 1994\n\
39 	The Regents of the University of California.  All rights reserved.\n";
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)basename.c	8.4 (Berkeley) 5/4/95";
45 #endif
46 static char rcsid[] = "$NetBSD: basename.c,v 1.9 1995/09/02 05:29:46 jtc Exp $";
47 #endif /* not lint */
48 
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <locale.h>
53 #include <unistd.h>
54 
55 void usage __P((void));
56 
57 int
58 main(argc, argv)
59 	int argc;
60 	char **argv;
61 {
62 	char *p;
63 	int ch;
64 
65 	setlocale(LC_ALL, "");
66 
67 	while ((ch = getopt(argc, argv, "")) != -1)
68 		switch(ch) {
69 		case '?':
70 		default:
71 			usage();
72 		}
73 	argc -= optind;
74 	argv += optind;
75 
76 	if (argc != 1 && argc != 2)
77 		usage();
78 
79 	/*
80 	 * (1) If string is // it is implementation defined whether steps (2)
81 	 *     through (5) are skipped or processed.
82 	 *
83 	 * (2) If string consists entirely of slash characters, string shall
84 	 *     be set to a single slash character.  In this case, skip steps
85 	 *     (3) through (5).
86 	 */
87 	for (p = *argv;; ++p) {
88 		if (!*p) {
89 			if (p > *argv)
90 				(void)printf("/\n");
91 			else
92 				(void)printf("\n");
93 			exit(0);
94 		}
95 		if (*p != '/')
96 			break;
97 	}
98 
99 	/*
100 	 * (3) If there are any trailing slash characters in string, they
101 	 *     shall be removed.
102 	 */
103 	for (; *p; ++p)
104 		continue;
105 	while (*--p == '/')
106 		continue;
107 	*++p = '\0';
108 
109 	/*
110 	 * (4) If there are any slash characters remaining in string, the
111 	 *     prefix of string up to an including the last slash character
112 	 *     in string shall be removed.
113 	 */
114 	while (--p >= *argv)
115 		if (*p == '/')
116 			break;
117 	++p;
118 
119 	/*
120 	 * (5) If the suffix operand is present, is not identical to the
121 	 *     characters remaining in string, and is identical to a suffix
122 	 *     of the characters remaining in string, the suffix suffix
123 	 *     shall be removed from string.
124 	 */
125 	if (*++argv) {
126 		int suffixlen, stringlen, off;
127 
128 		suffixlen = strlen(*argv);
129 		stringlen = strlen(p);
130 
131 		if (suffixlen < stringlen) {
132 			off = stringlen - suffixlen;
133 			if (!strcmp(p + off, *argv))
134 				p[off] = '\0';
135 		}
136 	}
137 	(void)printf("%s\n", p);
138 	exit(0);
139 }
140 
141 void
142 usage()
143 {
144 
145 	(void)fprintf(stderr, "usage: basename string [suffix]\n");
146 	exit(1);
147 }
148