1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2010 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 /*
28 * Copyright (c) 1984 Regents of the University of California.
29 * All rights reserved. The Berkeley software License Agreement
30 * specifies the terms and conditions for redistribution.
31 */
32
33 /*
34 * Return the number of the slot in the utmp file
35 * corresponding to the current user: try for file 0, 1, 2.
36 * To mimic the behavior of getttyent, we loop through utmp
37 * and try to find an entry with a matching line number.
38 * If we don't find one we return the index of the end of
39 * the file, so that the record can be added to the end of
40 * the file.
41 */
42 #include "../../sys/common/compat.h"
43 #include <sys/syscall.h>
44 #include <sys/fcntl.h>
45 #include <stdio.h>
46 #include <unistd.h>
47 #include <strings.h>
48
49 int
ttyslot(void)50 ttyslot(void)
51 {
52 char *tp, *p;
53 int s;
54 int fd;
55 struct utmpx utx;
56
57
58 if ((tp = ttyname(0)) == NULL &&
59 (tp = ttyname(1)) == NULL &&
60 (tp = ttyname(2)) == NULL)
61 return (0);
62 if ((p = rindex(tp, '/')) == NULL)
63 p = tp;
64 else
65 p++;
66
67 if ((fd = _syscall(SYS_openat,
68 AT_FDCWD, "/etc/utmpx", O_RDONLY)) == -1) {
69 perror("ttyslot: open of /etc/utmpx failed:");
70 return (0);
71 }
72
73 s = 0;
74 while (_read(fd, &utx, sizeof (struct utmpx)) > 0) {
75 s++;
76 if (strncmp(utx.ut_line, p, sizeof (utx.ut_line)) == 0) {
77 _syscall(SYS_close, fd);
78 return (s);
79 }
80 }
81 _syscall(SYS_close, fd);
82 return (s);
83 }
84