xref: /netbsd-src/usr.bin/dirname/dirname.c (revision ce0bb6e8d2e560ecacbe865a848624f94498063b)
1 /*	$NetBSD: dirname.c,v 1.5 1995/03/28 16:50:12 glass 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[] = "@(#)dirname.c	8.3 (Berkeley) 4/2/94";
45 #else
46 static char rcsid[] = "$NetBSD: dirname.c,v 1.5 1995/03/28 16:50:12 glass Exp $";
47 #endif
48 #endif /* not lint */
49 
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <locale.h>
53 
54 static void usage __P((void));
55 
56 int
57 main(argc, argv)
58 	int argc;
59 	char **argv;
60 {
61 	register char *p;
62 	int ch;
63 
64 	setlocale(LC_ALL, "");
65 
66 	while ((ch = getopt(argc, argv, "")) != -1)
67 		switch(ch) {
68 		case '?':
69 		default:
70 			usage();
71 		}
72 	argc -= optind;
73 	argv += optind;
74 
75 	if (argc != 1)
76 		usage();
77 
78 	/*
79 	 * (1) If string is //, skip steps (2) through (5).
80 	 * (2) If string consists entirely of slash characters, string
81 	 *     shall be set to a single slash character.  In this case,
82 	 *     skip steps (3) through (8).
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 	while (*--p == '/')
102 		continue;
103 	*++p = '\0';
104 
105 	/*
106 	 * (4) If there are no slash characters remaining in string,
107 	 *     string shall be set to a single period character.  In this
108 	 *     case skip steps (5) through (8).
109 	 *
110 	 * (5) If there are any trailing nonslash characters in string,
111 	 *     they shall be removed.
112 	 */
113 	while (--p >= *argv)
114 		if (*p == '/')
115 			break;
116 	++p;
117 	if (p == *argv) {
118 		(void)printf(".\n");
119 		exit(0);
120 	}
121 
122 	/*
123 	 * (6) If the remaining string is //, it is implementation defined
124 	 *     whether steps (7) and (8) are skipped or processed.
125 	 *
126 	 * This case has already been handled, as part of steps (1) and (2).
127 	 */
128 
129 	/*
130 	 * (7) If there are any trailing slash characters in string, they
131 	 *     shall be removed.
132 	 */
133 	while (--p >= *argv)
134 		if (*p != '/')
135 			break;
136 	++p;
137 
138 	/*
139 	 * (8) If the remaining string is empty, string shall be set to
140 	 *     a single slash character.
141 	 */
142 	*p = '\0';
143 	(void)printf("%s\n", p == *argv ? "/" : *argv);
144 	exit(0);
145 }
146 
147 static void
148 usage()
149 {
150 
151 	(void)fprintf(stderr, "usage: dirname path\n");
152 	exit(1);
153 }
154 
155