xref: /netbsd-src/usr.bin/talk/get_names.c (revision 5f7096188587a2c7c95fa3c69b78e1ec9c7923d0)
1 /*
2  * Copyright (c) 1983 Regents of the University of California.
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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 /*static char sccsid[] = "from: @(#)get_names.c	5.9 (Berkeley) 3/1/91";*/
36 static char rcsid[] = "$Id: get_names.c,v 1.2 1993/08/01 18:07:51 mycroft Exp $";
37 #endif /* not lint */
38 
39 #include <sys/param.h>
40 #include <sys/socket.h>
41 #include <protocols/talkd.h>
42 #include <pwd.h>
43 #include "talk.h"
44 
45 char	*getlogin();
46 char	*ttyname();
47 char	*rindex();
48 extern	CTL_MSG msg;
49 
50 /*
51  * Determine the local and remote user, tty, and machines
52  */
53 get_names(argc, argv)
54 	int argc;
55 	char *argv[];
56 {
57 	char hostname[MAXHOSTNAMELEN];
58 	char *his_name, *my_name;
59 	char *my_machine_name, *his_machine_name;
60 	char *my_tty, *his_tty;
61 	register char *cp;
62 
63 	if (argc < 2 ) {
64 		printf("Usage: talk user [ttyname]\n");
65 		exit(-1);
66 	}
67 	if (!isatty(0)) {
68 		printf("Standard input must be a tty, not a pipe or a file\n");
69 		exit(-1);
70 	}
71 	if ((my_name = getlogin()) == NULL) {
72 		struct passwd *pw;
73 
74 		if ((pw = getpwuid(getuid())) == NULL) {
75 			printf("You don't exist. Go away.\n");
76 			exit(-1);
77 		}
78 		my_name = pw->pw_name;
79 	}
80 	gethostname(hostname, sizeof (hostname));
81 	my_machine_name = hostname;
82 	/* check for, and strip out, the machine name of the target */
83 	for (cp = argv[1]; *cp && !index("@:!.", *cp); cp++)
84 		;
85 	if (*cp == '\0') {
86 		/* this is a local to local talk */
87 		his_name = argv[1];
88 		his_machine_name = my_machine_name;
89 	} else {
90 		if (*cp++ == '@') {
91 			/* user@host */
92 			his_name = argv[1];
93 			his_machine_name = cp;
94 		} else {
95 			/* host.user or host!user or host:user */
96 			his_name = cp;
97 			his_machine_name = argv[1];
98 		}
99 		*--cp = '\0';
100 	}
101 	if (argc > 2)
102 		his_tty = argv[2];	/* tty name is arg 2 */
103 	else
104 		his_tty = "";
105 	get_addrs(my_machine_name, his_machine_name);
106 	/*
107 	 * Initialize the message template.
108 	 */
109 	msg.vers = TALK_VERSION;
110 	msg.addr.sa_family = htons(AF_INET);
111 	msg.ctl_addr.sa_family = htons(AF_INET);
112 	msg.id_num = htonl(0);
113 	strncpy(msg.l_name, my_name, NAME_SIZE);
114 	msg.l_name[NAME_SIZE - 1] = '\0';
115 	strncpy(msg.r_name, his_name, NAME_SIZE);
116 	msg.r_name[NAME_SIZE - 1] = '\0';
117 	strncpy(msg.r_tty, his_tty, TTY_SIZE);
118 	msg.r_tty[TTY_SIZE - 1] = '\0';
119 }
120