get_names.c revision 1.2 
1/*	$OpenBSD: get_names.c,v 1.2 1996/06/26 05:40:22 deraadt Exp $	*/
2/*	$NetBSD: get_names.c,v 1.4 1994/12/09 02:14:16 jtc Exp $	*/
3
4/*
5 * Copyright (c) 1983, 1993
6 *	The Regents of the University of California.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#ifndef lint
38#if 0
39static char sccsid[] = "@(#)get_names.c	8.1 (Berkeley) 6/6/93";
40#endif
41static char rcsid[] = "$OpenBSD: get_names.c,v 1.2 1996/06/26 05:40:22 deraadt Exp $";
42#endif /* not lint */
43
44#include <sys/param.h>
45#include <sys/socket.h>
46#include <protocols/talkd.h>
47#include <pwd.h>
48#include <string.h>
49#include "talk.h"
50
51char	*getlogin();
52char	*ttyname();
53char	*rindex();
54extern	CTL_MSG msg;
55
56/*
57 * Determine the local and remote user, tty, and machines
58 */
59get_names(argc, argv)
60	int argc;
61	char *argv[];
62{
63	char hostname[MAXHOSTNAMELEN];
64	char *his_name, *my_name;
65	char *my_machine_name, *his_machine_name;
66	char *my_tty, *his_tty;
67	register char *cp;
68	char *names;
69
70	if (argc < 2 ) {
71		printf("Usage: talk user [ttyname]\n");
72		exit(-1);
73	}
74	if (!isatty(0)) {
75		printf("Standard input must be a tty, not a pipe or a file\n");
76		exit(-1);
77	}
78	if ((my_name = getlogin()) == NULL) {
79		struct passwd *pw;
80
81		if ((pw = getpwuid(getuid())) == NULL) {
82			printf("You don't exist. Go away.\n");
83			exit(-1);
84		}
85		my_name = pw->pw_name;
86	}
87	gethostname(hostname, sizeof (hostname));
88	my_machine_name = hostname;
89	/* check for, and strip out, the machine name of the target */
90	names = strdup(argv[1]);
91	for (cp = names; *cp && !index("@:!.", *cp); cp++)
92		;
93	if (*cp == '\0') {
94		/* this is a local to local talk */
95		his_name = names;
96		his_machine_name = my_machine_name;
97	} else {
98		if (*cp++ == '@') {
99			/* user@host */
100			his_name = names;
101			his_machine_name = cp;
102		} else {
103			/* host.user or host!user or host:user */
104			his_name = cp;
105			his_machine_name = names;
106		}
107		*--cp = '\0';
108	}
109	if (argc > 2)
110		his_tty = argv[2];	/* tty name is arg 2 */
111	else
112		his_tty = "";
113	get_addrs(my_machine_name, his_machine_name);
114	/*
115	 * Initialize the message template.
116	 */
117	msg.vers = TALK_VERSION;
118	msg.addr.sa_family = htons(AF_INET);
119	msg.ctl_addr.sa_family = htons(AF_INET);
120	msg.id_num = htonl(0);
121	strncpy(msg.l_name, my_name, NAME_SIZE);
122	msg.l_name[NAME_SIZE - 1] = '\0';
123	strncpy(msg.r_name, his_name, NAME_SIZE);
124	msg.r_name[NAME_SIZE - 1] = '\0';
125	strncpy(msg.r_tty, his_tty, TTY_SIZE);
126	msg.r_tty[TTY_SIZE - 1] = '\0';
127}
128