xref: /freebsd/sbin/conscontrol/conscontrol.c (revision 0f8f86b71f022b803e99151c19db81b280f245dc)
1 /*-
2  * Copyright (c) 2001 Jonathan Lemon <jlemon@FreeBSD.org>
3  * 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  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/types.h>
31 #include <sys/sysctl.h>
32 
33 #include <err.h>
34 #include <errno.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <unistd.h>
39 
40 #define DEVDIR	"/dev/"
41 
42 static void __dead2
43 usage(void)
44 {
45 
46 	(void)fprintf(stderr, "%s\n%s\n%s\n",
47 	    "usage: conscontrol [list]",
48 	    "       conscontrol mute on | off",
49 	    "       conscontrol add | delete console");
50 	exit(1);
51 }
52 
53 static void
54 consstatus(void)
55 {
56 	int mute;
57 	size_t len;
58 	char *buf, *p, *avail;
59 
60 	len = sizeof(mute);
61 	if (sysctlbyname("kern.consmute", &mute, &len, NULL, 0) == -1)
62 		err(1, "kern.consmute retrieval failed");
63 	if (sysctlbyname("kern.console", NULL, &len, NULL, 0) == -1)
64 		err(1, "kern.console estimate failed");
65 	if ((buf = malloc(len)) == NULL)
66 		errx(1, "kern.console malloc failed");
67 	if (sysctlbyname("kern.console", buf, &len, NULL, 0) == -1)
68 		err(1, "kern.console retrieval failed");
69 	if ((avail = strchr(buf, '/')) == NULL)
70 		errx(1, "kern.console format not understood");
71 	p = avail;
72 	*avail++ = '\0';
73 	if (p != buf)
74 		*--p = '\0';			/* remove trailing ',' */
75 	p = avail + strlen(avail);
76 	if (p != avail)
77 		*--p = '\0';			/* remove trailing ',' */
78 	printf("Configured: %s\n", buf);
79 	printf(" Available: %s\n", avail);
80 	printf("    Muting: %s\n", mute ? "on" : "off");
81 	free(buf);
82 }
83 
84 static void
85 consmute(const char *onoff)
86 {
87 	int mute;
88 	size_t len;
89 
90 	if (strcmp(onoff, "on") == 0)
91 		mute = 1;
92 	else if (strcmp(onoff, "off") == 0)
93 		mute = 0;
94 	else
95 		usage();
96 	len = sizeof(mute);
97 	if (sysctlbyname("kern.consmute", NULL, NULL, &mute, len) == -1)
98 		err(1, "could not change console muting");
99 }
100 
101 /*
102  * The name we supply to the sysctls should be an entry in /dev.  If
103  * the user has specified the full pathname in /dev, DTRT.  If he
104  * specifies a name in some other directory, it's an error.
105  */
106 
107 static char*
108 stripdev(char *devnam)
109 {
110 	if (memcmp (devnam, DEVDIR, strlen(DEVDIR)) == 0)
111 		return (&devnam[strlen(DEVDIR)]);	    /* remove /dev */
112 	else if (strchr (devnam, '/')) {
113 		fprintf(stderr, "Not a device in /dev: %s\n", devnam);
114 		return (NULL);				    /* end of string */
115 	} else
116 		return (devnam);			    /* passed */
117 }
118 
119 static void
120 consadd(char *devnam)
121 {
122 	size_t len;
123 
124 	devnam = stripdev(devnam);
125 	if (devnam == NULL)
126 		return;
127 	len = strlen(devnam);
128 	if (sysctlbyname("kern.console", NULL, NULL, devnam, len) == -1)
129 		err(1, "could not add %s as a console", devnam);
130 }
131 
132 static void
133 consdel(char *devnam)
134 {
135 	char *buf;
136 	size_t len;
137 
138 	devnam = stripdev(devnam);
139 	if (devnam == NULL)
140 		return;
141 	len = strlen(devnam) + sizeof("-");
142 	if ((buf = malloc(len)) == NULL)
143 		errx(1, "malloc failed");
144 	buf[0] = '-';
145 	strcpy(buf + 1, devnam);
146 	if (sysctlbyname("kern.console", NULL, NULL, buf, len) == -1)
147 		err(1, "could not remove %s as a console", devnam);
148 	free(buf);
149 }
150 
151 int
152 main(int argc, char **argv)
153 {
154 
155 	if (getopt(argc, argv, "") != -1)
156 		usage();
157 	argc -= optind;
158 	argv += optind;
159 
160 	if (argc > 0 && strcmp(argv[0], "list") != 0) {
161 		if (argc != 2)
162 			usage();
163 		if (strcmp(argv[0], "mute") == 0)
164 			consmute(argv[1]);
165 		else if (strcmp(argv[0], "add") == 0)
166 			consadd(argv[1]);
167 		else if (strcmp(argv[0], "delete") == 0)
168 			consdel(argv[1]);
169 		else
170 			usage();
171 	}
172 	consstatus();
173 	exit(0);
174 }
175