xref: /freebsd/usr.bin/biff/biff.c (revision 5b31cc94b10d4bb7109c6b27940a0fc76a44a331)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1993
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) 1980, 1993\n\
35 	The Regents of the University of California.  All rights reserved.\n";
36 #endif
37 
38 #if 0
39 #endif
40 
41 #include <sys/cdefs.h>
42 #include <sys/stat.h>
43 
44 #include <err.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <unistd.h>
48 
49 static void usage(void) __dead2;
50 
51 int
52 main(int argc, char *argv[])
53 {
54 	struct stat sb;
55 	int ch;
56 	char *name;
57 
58 
59 	while ((ch = getopt(argc, argv, "")) != -1)
60 		switch(ch) {
61 		case '?':
62 		default:
63 			usage();
64 		}
65 	argc -= optind;
66 	argv += optind;
67 
68 	if ((name = ttyname(STDIN_FILENO)) == NULL &&
69 	    (name = ttyname(STDOUT_FILENO)) == NULL &&
70 	    (name = ttyname(STDERR_FILENO)) == NULL)
71 		err(2, "unknown tty");
72 
73 	if (stat(name, &sb))
74 		err(2, "stat");
75 
76 	if (*argv == NULL) {
77 		(void)printf("is %s\n",
78 		    sb.st_mode & S_IXUSR ? "y" :
79 		    sb.st_mode & S_IXGRP ? "b" : "n");
80 		return (sb.st_mode & (S_IXUSR | S_IXGRP) ? 0 : 1);
81 
82 	}
83 
84 	switch (argv[0][0]) {
85 	case 'n':
86 		if (chmod(name, sb.st_mode & ~(S_IXUSR | S_IXGRP)) < 0)
87 			err(2, "%s", name);
88 		break;
89 	case 'y':
90 		if (chmod(name, (sb.st_mode & ~(S_IXUSR | S_IXGRP)) | S_IXUSR)
91 		    < 0)
92 			err(2, "%s", name);
93 		break;
94 	case 'b':
95 		if (chmod(name, (sb.st_mode & ~(S_IXUSR | S_IXGRP)) | S_IXGRP)
96 		    < 0)
97 			err(2, "%s", name);
98 		break;
99 	default:
100 		usage();
101 	}
102 	return (sb.st_mode & (S_IXUSR | S_IXGRP) ? 0 : 1);
103 }
104 
105 static void
106 usage(void)
107 {
108 	(void)fprintf(stderr, "usage: biff [n | y | b]\n");
109 	exit(2);
110 }
111