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#include <sys/stat.h>
33
34#include <err.h>
35#include <stdio.h>
36#include <stdlib.h>
37#include <unistd.h>
38
39static void usage(void) __dead2;
40
41int
42main(int argc, char *argv[])
43{
44	struct stat sb;
45	int ch;
46	char *name;
47
48
49	while ((ch = getopt(argc, argv, "")) != -1)
50		switch(ch) {
51		case '?':
52		default:
53			usage();
54		}
55	argc -= optind;
56	argv += optind;
57
58	if ((name = ttyname(STDIN_FILENO)) == NULL &&
59	    (name = ttyname(STDOUT_FILENO)) == NULL &&
60	    (name = ttyname(STDERR_FILENO)) == NULL)
61		err(2, "unknown tty");
62
63	if (stat(name, &sb))
64		err(2, "stat");
65
66	if (*argv == NULL) {
67		(void)printf("is %s\n",
68		    sb.st_mode & S_IXUSR ? "y" :
69		    sb.st_mode & S_IXGRP ? "b" : "n");
70		return (sb.st_mode & (S_IXUSR | S_IXGRP) ? 0 : 1);
71
72	}
73
74	switch (argv[0][0]) {
75	case 'n':
76		if (chmod(name, sb.st_mode & ~(S_IXUSR | S_IXGRP)) < 0)
77			err(2, "%s", name);
78		break;
79	case 'y':
80		if (chmod(name, (sb.st_mode & ~(S_IXUSR | S_IXGRP)) | S_IXUSR)
81		    < 0)
82			err(2, "%s", name);
83		break;
84	case 'b':
85		if (chmod(name, (sb.st_mode & ~(S_IXUSR | S_IXGRP)) | S_IXGRP)
86		    < 0)
87			err(2, "%s", name);
88		break;
89	default:
90		usage();
91	}
92	return (sb.st_mode & (S_IXUSR | S_IXGRP) ? 0 : 1);
93}
94
95static void
96usage(void)
97{
98	(void)fprintf(stderr, "usage: biff [n | y | b]\n");
99	exit(2);
100}
101