get_names.c revision 1.1 
1/*	$NetBSD: get_names.c,v 1.4 1994/12/09 02:14:16 jtc Exp $	*/
2
3/*
4 * Copyright (c) 1983, 1993
5 *	The Regents of the University of California.  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 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#ifndef lint
37#if 0
38static char sccsid[] = "@(#)get_names.c	8.1 (Berkeley) 6/6/93";
39#endif
40static char rcsid[] = "$NetBSD: get_names.c,v 1.4 1994/12/09 02:14:16 jtc Exp $";
41#endif /* not lint */
42
43#include <sys/param.h>
44#include <sys/socket.h>
45#include <protocols/talkd.h>
46#include <pwd.h>
47#include <string.h>
48#include "talk.h"
49
50char	*getlogin();
51char	*ttyname();
52char	*rindex();
53extern	CTL_MSG msg;
54
55/*
56 * Determine the local and remote user, tty, and machines
57 */
58get_names(argc, argv)
59	int argc;
60	char *argv[];
61{
62	char hostname[MAXHOSTNAMELEN];
63	char *his_name, *my_name;
64	char *my_machine_name, *his_machine_name;
65	char *my_tty, *his_tty;
66	register char *cp;
67	char *names;
68
69	if (argc < 2 ) {
70		printf("Usage: talk user [ttyname]\n");
71		exit(-1);
72	}
73	if (!isatty(0)) {
74		printf("Standard input must be a tty, not a pipe or a file\n");
75		exit(-1);
76	}
77	if ((my_name = getlogin()) == NULL) {
78		struct passwd *pw;
79
80		if ((pw = getpwuid(getuid())) == NULL) {
81			printf("You don't exist. Go away.\n");
82			exit(-1);
83		}
84		my_name = pw->pw_name;
85	}
86	gethostname(hostname, sizeof (hostname));
87	my_machine_name = hostname;
88	/* check for, and strip out, the machine name of the target */
89	names = strdup(argv[1]);
90	for (cp = names; *cp && !index("@:!.", *cp); cp++)
91		;
92	if (*cp == '\0') {
93		/* this is a local to local talk */
94		his_name = names;
95		his_machine_name = my_machine_name;
96	} else {
97		if (*cp++ == '@') {
98			/* user@host */
99			his_name = names;
100			his_machine_name = cp;
101		} else {
102			/* host.user or host!user or host:user */
103			his_name = cp;
104			his_machine_name = names;
105		}
106		*--cp = '\0';
107	}
108	if (argc > 2)
109		his_tty = argv[2];	/* tty name is arg 2 */
110	else
111		his_tty = "";
112	get_addrs(my_machine_name, his_machine_name);
113	/*
114	 * Initialize the message template.
115	 */
116	msg.vers = TALK_VERSION;
117	msg.addr.sa_family = htons(AF_INET);
118	msg.ctl_addr.sa_family = htons(AF_INET);
119	msg.id_num = htonl(0);
120	strncpy(msg.l_name, my_name, NAME_SIZE);
121	msg.l_name[NAME_SIZE - 1] = '\0';
122	strncpy(msg.r_name, his_name, NAME_SIZE);
123	msg.r_name[NAME_SIZE - 1] = '\0';
124	strncpy(msg.r_tty, his_tty, TTY_SIZE);
125	msg.r_tty[TTY_SIZE - 1] = '\0';
126}
127