xref: /freebsd/usr.bin/biff/biff.c (revision 21fdc27a054f668c8b6c2be503fa68622e5226da)
1 /*
2  * Copyright (c) 1980, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1980, 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif
39 
40 #if 0
41 #ifndef lint
42 static char sccsid[] = "@(#)biff.c	8.1 (Berkeley) 6/6/93";
43 #endif
44 #endif
45 
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
48 
49 #include <sys/stat.h>
50 
51 #include <err.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <unistd.h>
55 
56 static void usage(void);
57 
58 int
59 main(int argc, char *argv[])
60 {
61 	struct stat sb;
62 	int ch;
63 	char *name;
64 
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 ((name = ttyname(STDIN_FILENO)) == NULL &&
76 	    (name = ttyname(STDOUT_FILENO)) == NULL &&
77 	    (name = ttyname(STDERR_FILENO)) == NULL)
78 		err(2, "unknown tty");
79 
80 	if (stat(name, &sb))
81 		err(2, "stat");
82 
83 	if (*argv == NULL) {
84 		(void)printf("is %s\n",
85 		    sb.st_mode & S_IXUSR ? "y" :
86 		    sb.st_mode & S_IXGRP ? "b" : "n");
87 		return (sb.st_mode & (S_IXUSR | S_IXGRP) ? 0 : 1);
88 
89 	}
90 
91 	switch (argv[0][0]) {
92 	case 'n':
93 		if (chmod(name, sb.st_mode & ~(S_IXUSR | S_IXGRP)) < 0)
94 			err(2, "%s", name);
95 		break;
96 	case 'y':
97 		if (chmod(name, (sb.st_mode & ~(S_IXUSR | S_IXGRP)) | S_IXUSR)
98 		    < 0)
99 			err(2, "%s", name);
100 		break;
101 	case 'b':
102 		if (chmod(name, (sb.st_mode & ~(S_IXUSR | S_IXGRP)) | S_IXGRP)
103 		    < 0)
104 			err(2, "%s", name);
105 		break;
106 	default:
107 		usage();
108 	}
109 	return (sb.st_mode & (S_IXUSR | S_IXGRP) ? 0 : 1);
110 }
111 
112 static void
113 usage(void)
114 {
115 	(void)fprintf(stderr, "usage: biff [n | y | b]\n");
116 	exit(2);
117 }
118