xref: /netbsd-src/usr.bin/basename/basename.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: basename.c,v 1.11 2003/08/07 11:13:10 agc 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 1.11 2003/08/07 11:13:10 agc 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 int main __P((int, char **));
52 void usage __P((void));
53 
54 int
55 main(argc, argv)
56 	int argc;
57 	char **argv;
58 {
59 	char *p;
60 	int ch;
61 
62 	setlocale(LC_ALL, "");
63 
64 	while ((ch = getopt(argc, argv, "")) != -1)
65 		switch(ch) {
66 		case '?':
67 		default:
68 			usage();
69 		}
70 	argc -= optind;
71 	argv += optind;
72 
73 	if (argc != 1 && argc != 2)
74 		usage();
75 
76 	/*
77 	 * (1) If string is // it is implementation defined whether steps (2)
78 	 *     through (5) are skipped or processed.
79 	 *
80 	 * (2) If string consists entirely of slash characters, string shall
81 	 *     be set to a single slash character.  In this case, skip steps
82 	 *     (3) through (5).
83 	 */
84 	for (p = *argv;; ++p) {
85 		if (!*p) {
86 			if (p > *argv)
87 				(void)printf("/\n");
88 			else
89 				(void)printf("\n");
90 			exit(0);
91 		}
92 		if (*p != '/')
93 			break;
94 	}
95 
96 	/*
97 	 * (3) If there are any trailing slash characters in string, they
98 	 *     shall be removed.
99 	 */
100 	for (; *p; ++p)
101 		continue;
102 	while (*--p == '/')
103 		continue;
104 	*++p = '\0';
105 
106 	/*
107 	 * (4) If there are any slash characters remaining in string, the
108 	 *     prefix of string up to an including the last slash character
109 	 *     in string shall be removed.
110 	 */
111 	while (--p >= *argv)
112 		if (*p == '/')
113 			break;
114 	++p;
115 
116 	/*
117 	 * (5) If the suffix operand is present, is not identical to the
118 	 *     characters remaining in string, and is identical to a suffix
119 	 *     of the characters remaining in string, the suffix suffix
120 	 *     shall be removed from string.
121 	 */
122 	if (*++argv) {
123 		int suffixlen, stringlen, off;
124 
125 		suffixlen = strlen(*argv);
126 		stringlen = strlen(p);
127 
128 		if (suffixlen < stringlen) {
129 			off = stringlen - suffixlen;
130 			if (!strcmp(p + off, *argv))
131 				p[off] = '\0';
132 		}
133 	}
134 	(void)printf("%s\n", p);
135 	exit(0);
136 }
137 
138 void
139 usage()
140 {
141 
142 	(void)fprintf(stderr, "usage: basename string [suffix]\n");
143 	exit(1);
144 }
145