get_names.c revision 1.21 
1/*	$OpenBSD: get_names.c,v 1.21 2016/02/01 07:29:25 mestre 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. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#include <sys/socket.h>
34
35#include <err.h>
36#include <limits.h>
37#include <pwd.h>
38#include <stdlib.h>
39#include <string.h>
40#include <unistd.h>
41
42#include "talk.h"
43
44extern	CTL_MSG msg;
45
46/*
47 * Determine the local and remote user, tty, and machines
48 */
49void
50get_names(int argc, char *argv[])
51{
52	char hostname[HOST_NAME_MAX+1];
53	char *his_name, *my_name;
54	char *my_machine_name, *his_machine_name;
55	char *his_tty;
56	char *cp;
57	char *names;
58
59	if (argc > 1 && !strcmp(argv[1], "-H")) {
60		argv[1] = argv[0];
61		++argv;
62		--argc;
63		high_print = 1;
64	}
65
66	if (argc > 1 && !strcmp(argv[1], "-s")) {
67		argv[1] = argv[0];
68		++argv;
69		--argc;
70		smooth_scroll = TRUE;
71	}
72
73	if ((argc < 2 ) || ('@' == argv[1][0])) {
74		extern char *__progname;
75		fprintf(stderr, "usage: %s [-Hs] person [ttyname]\n", __progname);
76		exit(1);
77	}
78	if (!isatty(STDIN_FILENO))
79		errx(1, "standard input must be a tty, not a pipe or a file");
80
81	if ((my_name = getlogin()) == NULL) {
82		struct passwd *pw;
83
84		if ((pw = getpwuid(getuid())) == NULL)
85			errx(1, "you don't exist in the passwd file.");
86		my_name = pw->pw_name;
87	}
88	gethostname(hostname, sizeof (hostname));
89	my_machine_name = hostname;
90	/* check for, and strip out, the machine name of the target */
91	names = strdup(argv[1]);
92	if (names == NULL)
93		errx(1, "out of memory");
94	for (cp = names; *cp && !strchr("@:!.", *cp); cp++)
95		;
96	if (*cp == '\0') {
97		/* this is a local to local talk */
98		his_name = names;
99		his_machine_name = my_machine_name;
100	} else {
101		if (*cp++ == '@') {
102			/* user@host */
103			his_name = names;
104			his_machine_name = cp;
105		} else {
106			/* host.user or host!user or host:user */
107			his_name = cp;
108			his_machine_name = names;
109		}
110		*--cp = '\0';
111	}
112	if (argc > 2)
113		his_tty = argv[2];	/* tty name is arg 2 */
114	else
115		his_tty = "";
116	get_addrs(my_machine_name, his_machine_name);
117	/*
118	 * Initialize the message template.
119	 */
120	msg.vers = TALK_VERSION;
121	msg.addr.sa_family = htons(AF_INET);
122	msg.ctl_addr.sa_family = htons(AF_INET);
123	msg.id_num = htonl(0);
124	strncpy(msg.l_name, my_name, NAME_SIZE);
125	msg.l_name[NAME_SIZE - 1] = '\0';
126	strncpy(msg.r_name, his_name, NAME_SIZE);
127	msg.r_name[NAME_SIZE - 1] = '\0';
128	strncpy(msg.r_tty, his_tty, TTY_SIZE);
129	msg.r_tty[TTY_SIZE - 1] = '\0';
130	free(names);
131}
132