xref: /illumos-gate/usr/src/cmd/cmd-inet/usr.bin/talk/get_names.c (revision b7daf79982d77b491ef9662483cd4549e0e5da9a)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * University Copyright- Copyright (c) 1982, 1986, 1988
32  * The Regents of the University of California
33  * All Rights Reserved
34  *
35  * University Acknowledgment- Portions of this document are derived from
36  * software developed by the University of California, Berkeley, and its
37  * contributors.
38  */
39 
40 #pragma ident	"%Z%%M%	%I%	%E% SMI"
41 
42 #include "talk.h"
43 #include "ctl.h"
44 #include <locale.h>
45 #include <pwd.h>
46 #include <sys/systeminfo.h>
47 
48 char *getlogin(), *ttyname(int);
49 
50 extern CTL_MSG msg;
51 
52 /*
53  * Determine the local and remote user, tty, and machines
54  */
55 
56 struct hostent *gethostbyname();
57 
58 void
59 get_names(argc, argv)
60 int argc;
61 char *argv[];
62 {
63 	char hostname[HOST_NAME_LENGTH + 1];
64 	char *rem_name;
65 	char *my_name;
66 	char *my_machine_name;
67 	char *rem_machine_name;
68 	char *my_tty;
69 	char *rem_tty;
70 	char *ptr;
71 	int name_length;
72 
73 	if (argc < 2) {
74 		fprintf(stderr,
75 		    "Usage: talk %s\n", gettext("address [terminal]"));
76 		exit(1);
77 	}
78 	if (!isatty(0)) {
79 		fprintf(stderr,
80 	gettext("Standard input must be a tty, not a pipe or a file\n"));
81 		exit(1);
82 	}
83 
84 	if (!isatty(1)) {
85 		fprintf(stderr,
86 	gettext("Standard output must be a tty, not a pipe or a file\n"));
87 		exit(1);
88 	}
89 
90 	if ((my_name = getlogin()) == NULL) {
91 	struct passwd *pass = getpwuid(getuid());
92 	if (pass != NULL)
93 		my_name = pass->pw_name;
94 	}
95 	if (my_name == NULL) {
96 		fprintf(stderr,
97 	gettext("Who are you?  You have no entry in /etc/utmp!  Aborting..\n"));
98 		exit(1);
99 	}
100 
101 	name_length = HOST_NAME_LENGTH;
102 	(void) sysinfo(SI_HOSTNAME, hostname, name_length);
103 	my_machine_name = hostname;
104 
105 	my_tty = strrchr(ttyname(0), '/') + 1;
106 
107 	/*
108 	 * check for, and strip out, the machine name of the target
109 	 */
110 
111 	for (ptr = argv[1]; *ptr != '\0' &&
112 			 *ptr != '@' &&
113 			 *ptr != ':' &&
114 			 *ptr != '!' &&
115 			 *ptr != '.'; ptr++) {
116 	}
117 
118 	if (*ptr == '\0') {
119 
120 		/* this is a local to local talk */
121 
122 	rem_name = argv[1];
123 	rem_machine_name = my_machine_name;
124 
125 	} else {
126 
127 	if (*ptr == '@') {
128 		/* user@host */
129 		rem_name = argv[1];
130 		rem_machine_name = ptr + 1;
131 	} else {
132 		/* host.user or host!user or host:user */
133 		rem_name = ptr + 1;
134 		rem_machine_name = argv[1];
135 	}
136 	*ptr = '\0';
137 	}
138 
139 
140 	if (argc > 2) {
141 	rem_tty = argv[2];	/* tty name is arg 2 */
142 	} else {
143 	rem_tty = "";
144 	}
145 
146 	get_addrs(my_machine_name, rem_machine_name);
147 
148 	/* Load these useful values into the standard message header */
149 
150 	msg.id_num = 0;
151 
152 	strncpy(msg.l_name, my_name, NAME_SIZE);
153 	msg.l_name[NAME_SIZE - 1] = '\0';
154 
155 	strncpy(msg.r_name, rem_name, NAME_SIZE);
156 	msg.r_name[NAME_SIZE - 1] = '\0';
157 
158 	strncpy(msg.r_tty, rem_tty, TTY_SIZE);
159 	msg.r_tty[TTY_SIZE - 1] = '\0';
160 }
161