1 /*
2 * Copyright (c) 1983, 1993
3 * The Regents of the University of California. 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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #include <sys/cdefs.h>
31
32 __FBSDID("$FreeBSD: stable/9/usr.bin/talk/get_names.c 216370 2010-12-11 08:32:16Z joel $");
33
34 #ifndef lint
35 static const char sccsid[] = "@(#)get_names.c 8.1 (Berkeley) 6/6/93";
36 #endif
37
38 #include <sys/param.h>
39
40 #include <err.h>
41 #include <pwd.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45
46 #include "talk.h"
47
48 extern CTL_MSG msg;
49
50 static void
usage(void)51 usage(void)
52 {
53 fprintf(stderr, "usage: talk person [ttyname]\n");
54 exit(1);
55 }
56
57 /*
58 * Determine the local and remote user, tty, and machines
59 */
60 void
get_names(int argc,char * argv[])61 get_names(int argc, char *argv[])
62 {
63 char hostname[MAXHOSTNAMELEN];
64 char *his_name, *my_name;
65 const char *my_machine_name, *his_machine_name;
66 const char *his_tty;
67 char *cp;
68
69 if (argc < 2 )
70 usage();
71 if (!isatty(0))
72 errx(1, "standard input must be a tty, not a pipe or a file");
73 if ((my_name = getlogin()) == NULL) {
74 struct passwd *pw;
75
76 if ((pw = getpwuid(getuid())) == NULL)
77 errx(1, "you don't exist. Go away");
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 my_machine_name = his_machine_name = "localhost";
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 */
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 strlcpy(msg.l_name, my_name, NAME_SIZE);
114 strlcpy(msg.r_name, his_name, NAME_SIZE);
115 strlcpy(msg.r_tty, his_tty, TTY_SIZE);
116 }
117