1/*-
2 * Copyright (c) 2008 Bruce Simpson.
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 * $FreeBSD$
27 */
28
29#include <sys/param.h>
30#include <sys/types.h>
31#include <sys/ioctl.h>
32
33#include <stdlib.h>
34#include <stdio.h>
35#include <string.h>
36#include <errno.h>
37#include <err.h>
38#include <fcntl.h>
39#include <unistd.h>
40
41#include <libgen.h>
42#include <sysexits.h>
43
44#define DEVPATHNAME "/dev"
45
46int
47main(int argc, char *argv[])
48{
49	char *progname;
50	char *ttyname;
51	int fd;
52	int dofree;
53
54	dofree = 0;
55
56	progname = basename(argv[0]);
57	if (argc != 2)
58		errx(EX_USAGE, "usage: %s <ttyname>\n", progname);
59	if (geteuid() != 0)
60		errx(EX_NOPERM, "Sorry\n");
61
62	if (argv[1][0] == '/') {
63		ttyname = argv[1];
64	} else {
65		size_t len, maxpath, result;
66
67		len = strlen(argv[1]) + sizeof(DEVPATHNAME) + 1;
68
69		maxpath = pathconf(DEVPATHNAME, _PC_PATH_MAX);
70		if (len > maxpath) {
71			warnc(ENAMETOOLONG, ttyname);
72			exit(EX_DATAERR);
73		}
74
75		ttyname = malloc(len);
76		if (ttyname == NULL) {
77			warnc(ENOMEM, "malloc");
78			exit(EX_OSERR);
79		}
80		dofree = 1;
81
82		result = snprintf(ttyname, len, "%s/%s", DEVPATHNAME, argv[1]);
83		if (result >= len)
84			warnc(ENOMEM, "snprintf");
85	}
86
87	fd = open(ttyname, O_RDWR);
88	if (fd == -1) {
89		warnc(errno, "open %s", ttyname);
90		if (dofree)
91			free(ttyname);
92		exit(EX_OSERR);
93	}
94
95	if (0 != ioctl(fd, TIOCNXCL, 0))
96		warnc(errno, "ioctl TIOCNXCL %s", ttyname);
97
98	if (dofree)
99		free(ttyname);
100	exit(0);
101}
102