xref: /freebsd/usr.bin/basename/basename.c (revision d11f81afd5a4a71d5f725950b0592ca212084780)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
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 #ifndef lint
33 static const char copyright[] =
34 "@(#) Copyright (c) 1991, 1993, 1994\n\
35 	The Regents of the University of California.  All rights reserved.\n";
36 #endif
37 
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)basename.c	8.4 (Berkeley) 5/4/95";
41 #endif /* not lint */
42 #endif
43 
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 #include <capsicum_helpers.h>
48 #include <err.h>
49 #include <libgen.h>
50 #include <limits.h>
51 #include <locale.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 #include <wchar.h>
57 
58 void stripsuffix(char *, const char *, size_t);
59 void usage(void);
60 
61 int
62 main(int argc, char **argv)
63 {
64 	char *p, *suffix;
65 	size_t suffixlen;
66 	int aflag, ch;
67 
68 	setlocale(LC_ALL, "");
69 
70 	if (caph_limit_stdio() < 0 || caph_enter() < 0)
71 		err(1, "capsicum");
72 
73 	aflag = 0;
74 	suffix = NULL;
75 	suffixlen = 0;
76 
77 	while ((ch = getopt(argc, argv, "as:")) != -1)
78 		switch(ch) {
79 		case 'a':
80 			aflag = 1;
81 			break;
82 		case 's':
83 			suffix = optarg;
84 			break;
85 		case '?':
86 		default:
87 			usage();
88 		}
89 	argc -= optind;
90 	argv += optind;
91 
92 	if (argc < 1)
93 		usage();
94 
95 	if (!*argv[0]) {
96 		printf("\n");
97 		exit(0);
98 	}
99 	if ((p = basename(argv[0])) == NULL)
100 		err(1, "%s", argv[0]);
101 	if ((suffix == NULL && !aflag) && argc == 2) {
102 		suffix = argv[1];
103 		argc--;
104 	}
105 	if (suffix != NULL)
106 		suffixlen = strlen(suffix);
107 	while (argc--) {
108 		if ((p = basename(*argv)) == NULL)
109 			err(1, "%s", argv[0]);
110 		stripsuffix(p, suffix, suffixlen);
111 		argv++;
112 		(void)printf("%s\n", p);
113 	}
114 	exit(0);
115 }
116 
117 void
118 stripsuffix(char *p, const char *suffix, size_t suffixlen)
119 {
120 	char *q, *r;
121 	mbstate_t mbs;
122 	size_t n;
123 
124 	if (suffixlen && (q = strchr(p, '\0') - suffixlen) > p &&
125 	    strcmp(suffix, q) == 0) {
126 		/* Ensure that the match occurred on a character boundary. */
127 		memset(&mbs, 0, sizeof(mbs));
128 		for (r = p; r < q; r += n) {
129 			n = mbrlen(r, MB_LEN_MAX, &mbs);
130 			if (n == (size_t)-1 || n == (size_t)-2) {
131 				memset(&mbs, 0, sizeof(mbs));
132 				n = 1;
133 			}
134 		}
135 		/* Chop off the suffix. */
136 		if (q == r)
137 			*q = '\0';
138 	}
139 }
140 
141 void
142 usage(void)
143 {
144 
145 	(void)fprintf(stderr,
146 "usage: basename string [suffix]\n"
147 "       basename [-a] [-s suffix] string [...]\n");
148 	exit(1);
149 }
150