xref: /netbsd-src/usr.bin/basename/basename.c (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
1 /*-
2  * Copyright (c) 1991 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 char copyright[] =
36 "@(#) Copyright (c) 1991 The Regents of the University of California.\n\
37  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 /*static char sccsid[] = "from: @(#)basename.c	5.1 (Berkeley) 3/9/91";*/
42 static char rcsid[] = "$Id: basename.c,v 1.5 1993/11/19 19:58:46 jtc Exp $";
43 #endif /* not lint */
44 
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <locale.h>
49 
50 static void usage __P((void));
51 
52 int
53 main(argc, argv)
54 	int argc;
55 	char **argv;
56 {
57 	register char *p;
58 	int ch;
59 
60 	setlocale(LC_ALL, "");
61 
62 	while ((ch = getopt(argc, argv, "")) != -1)
63 		switch(ch) {
64 		case '?':
65 		default:
66 			usage();
67 		}
68 	argc -= optind;
69 	argv += optind;
70 
71 	if (argc != 1 && argc != 2)
72 		usage();
73 
74 	/*
75 	 * (1) If string is // it is implementation defined whether steps (2)
76 	 *     through (5) are skipped or processed.
77 	 *
78 	 * (2) If string consists entirely of slash characters, string shall
79 	 *     be set to a single slash character.  In this case, skip steps
80 	 *     (3) through (5).
81 	 */
82 	for (p = *argv;; ++p) {
83 		if (!*p) {
84 			if (p > *argv)
85 				(void)printf("/\n");
86 			else
87 				(void)printf("\n");
88 			exit(0);
89 		}
90 		if (*p != '/')
91 			break;
92 	}
93 
94 	/*
95 	 * (3) If there are any trailing slash characters in string, they
96 	 *     shall be removed.
97 	 */
98 	for (; *p; ++p)
99 		;
100 	while (*--p == '/')
101 		;
102 	*++p = '\0';
103 
104 	/*
105 	 * (4) If there are any slash characters remaining in string, the
106 	 *     prefix of string up to an including the last slash character
107 	 *     in string shall be removed.
108 	 */
109 	while (--p >= *argv)
110 		if (*p == '/')
111 			break;
112 	++p;
113 
114 	/*
115 	 * (5) If the suffix operand is present, is not identical to the
116 	 *     characters remaining in string, and is identical to a suffix
117 	 *     of the characters remaining in string, the suffix suffix
118 	 *     shall be removed from string.
119 	 */
120 	if (*++argv) {
121 		int suffixlen, stringlen, off;
122 
123 		suffixlen = strlen(*argv);
124 		stringlen = strlen(p);
125 
126 		if (suffixlen < stringlen) {
127 			off = stringlen - suffixlen;
128 			if (!strcmp(p + off, *argv))
129 				p[off] = '\0';
130 		}
131 	}
132 	(void)printf("%s\n", p);
133 	exit(0);
134 }
135 
136 static void
137 usage()
138 {
139 	(void)fprintf(stderr, "usage: basename string [suffix]\n");
140 	exit(1);
141 }
142