freebsd-dev/sbin/conscontrol/conscontrol.c
Greg Lehey ffb19b1385 Recognize if the user supplies the full pathname to /dev/console and friends,
and DTRT.

Explain if he supplies a pathname that is not in /dev.
2004-02-17 04:51:06 +00:00

175 lines
4.5 KiB
C

/*-
* Copyright (c) 2001 Jonathan Lemon <jlemon@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/sysctl.h>
#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define DEVDIR "/dev/"
static void __dead2
usage(void)
{
(void)fprintf(stderr, "%s\n%s\n%s\n",
"usage: conscontrol [list]",
" conscontrol mute on | off",
" conscontrol add | delete console");
exit(1);
}
static void
consstatus(void)
{
int mute;
size_t len;
char *buf, *p, *avail;
len = sizeof(mute);
if (sysctlbyname("kern.consmute", &mute, &len, NULL, 0) == -1)
err(1, "kern.consmute retrieval failed");
if (sysctlbyname("kern.console", NULL, &len, NULL, 0) == -1)
err(1, "kern.console estimate failed");
if ((buf = malloc(len)) == NULL)
errx(1, "kern.console malloc failed");
if (sysctlbyname("kern.console", buf, &len, NULL, 0) == -1)
err(1, "kern.console retrieval failed");
if ((avail = strchr(buf, '/')) == NULL)
errx(1, "kern.console format not understood");
p = avail;
*avail++ = '\0';
if (p != buf)
*--p = '\0'; /* remove trailing ',' */
p = avail + strlen(avail);
if (p != avail)
*--p = '\0'; /* remove trailing ',' */
printf("Configured: %s\n", buf);
printf(" Available: %s\n", avail);
printf(" Muting: %s\n", mute ? "on" : "off");
free(buf);
}
static void
consmute(const char *onoff)
{
int mute;
size_t len;
if (strcmp(onoff, "on") == 0)
mute = 1;
else if (strcmp(onoff, "off") == 0)
mute = 0;
else
usage();
len = sizeof(mute);
if (sysctlbyname("kern.consmute", NULL, NULL, &mute, len) == -1)
err(1, "could not change console muting");
}
/*
* The name we supply to the sysctls should be an entry in /dev. If
* the user has specified the full pathname in /dev, DTRT. If he
* specifies a name in some other directory, it's an error.
*/
static char*
stripdev(char *devnam)
{
if (memcmp (devnam, DEVDIR, strlen(DEVDIR)) == 0)
return (&devnam[strlen(DEVDIR)]); /* remove /dev */
else if (strchr (devnam, '/')) {
fprintf(stderr, "Not a device in /dev: %s\n", devnam);
return (NULL); /* end of string */
} else
return (devnam); /* passed */
}
static void
consadd(char *devnam)
{
size_t len;
devnam = stripdev(devnam);
if (devnam == NULL)
return;
len = strlen(devnam);
if (sysctlbyname("kern.console", NULL, NULL, devnam, len) == -1)
err(1, "could not add %s as a console", devnam);
}
static void
consdel(char *devnam)
{
char *buf;
size_t len;
devnam = stripdev(devnam);
if (devnam == NULL)
return;
len = strlen(devnam) + sizeof("-");
if ((buf = malloc(len)) == NULL)
errx(1, "malloc failed");
buf[0] = '-';
strcpy(buf + 1, devnam);
if (sysctlbyname("kern.console", NULL, NULL, buf, len) == -1)
err(1, "could not remove %s as a console", devnam);
free(buf);
}
int
main(int argc, char **argv)
{
if (getopt(argc, argv, "") != -1)
usage();
argc -= optind;
argv += optind;
if (argc > 0 && strcmp(argv[0], "list") != 0) {
if (argc != 2)
usage();
if (strcmp(argv[0], "mute") == 0)
consmute(argv[1]);
else if (strcmp(argv[0], "add") == 0)
consadd(argv[1]);
else if (strcmp(argv[0], "delete") == 0)
consdel(argv[1]);
else
usage();
}
consstatus();
exit(0);
}