xref: /freebsd/sbin/conscontrol/conscontrol.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2001 Jonathan Lemon <jlemon@FreeBSD.org>
5  * 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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/types.h>
30 #include <sys/sysctl.h>
31 #include <sys/ioctl.h>
32 #include <sys/ttycom.h>
33 
34 #include <err.h>
35 #include <errno.h>
36 #include <fcntl.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <unistd.h>
41 
42 #define DEVDIR	"/dev/"
43 
44 static void __dead2
45 usage(void)
46 {
47 
48 	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n",
49 	    "usage: conscontrol [list]",
50 	    "       conscontrol mute on | off",
51 	    "       conscontrol add | delete console",
52 	    "       conscontrol set | unset console");
53 	exit(1);
54 }
55 
56 static void
57 consstatus(void)
58 {
59 	int mute;
60 	size_t len;
61 	char *buf, *p, *avail;
62 
63 	len = sizeof(mute);
64 	if (sysctlbyname("kern.consmute", &mute, &len, NULL, 0) == -1)
65 		err(1, "kern.consmute retrieval failed");
66 	if (sysctlbyname("kern.console", NULL, &len, NULL, 0) == -1)
67 		err(1, "kern.console estimate failed");
68 	if ((buf = malloc(len)) == NULL)
69 		errx(1, "kern.console malloc failed");
70 	if (sysctlbyname("kern.console", buf, &len, NULL, 0) == -1)
71 		err(1, "kern.console retrieval failed");
72 	if ((avail = strchr(buf, '/')) == NULL)
73 		errx(1, "kern.console format not understood");
74 	p = avail;
75 	*avail++ = '\0';
76 	if (p != buf)
77 		*--p = '\0';			/* remove trailing ',' */
78 	p = avail + strlen(avail);
79 	if (p != avail)
80 		*--p = '\0';			/* remove trailing ',' */
81 	printf("Configured: %s\n", buf);
82 	printf(" Available: %s\n", avail);
83 	printf("    Muting: %s\n", mute ? "on" : "off");
84 	free(buf);
85 }
86 
87 static void
88 consmute(const char *onoff)
89 {
90 	int mute;
91 	size_t len;
92 
93 	if (strcmp(onoff, "on") == 0)
94 		mute = 1;
95 	else if (strcmp(onoff, "off") == 0)
96 		mute = 0;
97 	else
98 		usage();
99 	len = sizeof(mute);
100 	if (sysctlbyname("kern.consmute", NULL, NULL, &mute, len) == -1)
101 		err(1, "could not change console muting");
102 }
103 
104 /*
105  * The name we supply to the sysctls should be an entry in /dev.  If
106  * the user has specified the full pathname in /dev, DTRT.  If he
107  * specifies a name in some other directory, it's an error.
108  */
109 
110 static char*
111 stripdev(char *devnam)
112 {
113 	if (memcmp (devnam, DEVDIR, strlen(DEVDIR)) == 0)
114 		return (&devnam[strlen(DEVDIR)]);	    /* remove /dev */
115 	else if (strchr (devnam, '/')) {
116 		fprintf(stderr, "Not a device in /dev: %s\n", devnam);
117 		return (NULL);				    /* end of string */
118 	} else
119 		return (devnam);			    /* passed */
120 }
121 
122 static void
123 consadd(char *devnam)
124 {
125 	size_t len;
126 
127 	devnam = stripdev(devnam);
128 	if (devnam == NULL)
129 		return;
130 	len = strlen(devnam);
131 	if (sysctlbyname("kern.console", NULL, NULL, devnam, len) == -1)
132 		err(1, "could not add %s as a console", devnam);
133 }
134 
135 static void
136 consdel(char *devnam)
137 {
138 	char *buf;
139 	size_t len;
140 
141 	devnam = stripdev(devnam);
142 	if (devnam == NULL)
143 		return;
144 	len = strlen(devnam) + sizeof("-");
145 	if ((buf = malloc(len)) == NULL)
146 		errx(1, "malloc failed");
147 	buf[0] = '-';
148 	strcpy(buf + 1, devnam);
149 	if (sysctlbyname("kern.console", NULL, NULL, buf, len) == -1)
150 		err(1, "could not remove %s as a console", devnam);
151 	free(buf);
152 }
153 
154 static void
155 consset(char *devnam, int flag)
156 {
157 	int ttyfd;
158 
159 	ttyfd = open(devnam, O_RDONLY);
160 	if (ttyfd == -1)
161 		err(1, "opening %s", devnam);
162 	if (ioctl(ttyfd, TIOCCONS, &flag) == -1)
163 		err(1, "could not %s %s as virtual console",
164 		    flag ? "set" : "unset", devnam);
165 	close(ttyfd);
166 }
167 
168 int
169 main(int argc, char **argv)
170 {
171 
172 	if (getopt(argc, argv, "") != -1)
173 		usage();
174 	argc -= optind;
175 	argv += optind;
176 
177 	if (argc > 0 && strcmp(argv[0], "list") != 0) {
178 		if (argc != 2)
179 			usage();
180 		else if (strcmp(argv[0], "mute") == 0)
181 			consmute(argv[1]);
182 		else if (strcmp(argv[0], "add") == 0)
183 			consadd(argv[1]);
184 		else if (strcmp(argv[0], "delete") == 0)
185 			consdel(argv[1]);
186 		else if (strcmp(argv[0], "set") == 0)
187 			consset(argv[1], 1);
188 		else if (strcmp(argv[0], "unset") == 0)
189 			consset(argv[1], 0);
190 		else
191 			usage();
192 	}
193 	consstatus();
194 	exit(0);
195 }
196