xref: /illumos-gate/usr/src/cmd/cmd-inet/usr.bin/talk/get_names.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
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 2017 Gary Mills
24  * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  */
27 
28 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
29 /*	  All Rights Reserved  	*/
30 
31 /*
32  * University Copyright- Copyright (c) 1982, 1986, 1988
33  * The Regents of the University of California
34  * All Rights Reserved
35  *
36  * University Acknowledgment- Portions of this document are derived from
37  * software developed by the University of California, Berkeley, and its
38  * contributors.
39  */
40 
41 #include "talk.h"
42 #include "ctl.h"
43 #include <locale.h>
44 #include <pwd.h>
45 #include <sys/systeminfo.h>
46 
47 char *getlogin(), *ttyname(int);
48 
49 extern CTL_MSG msg;
50 
51 /*
52  * Determine the local and remote user, tty, and machines
53  */
54 
55 struct hostent *gethostbyname();
56 
57 void
58 get_names(argc, argv)
59 int argc;
60 char *argv[];
61 {
62 	char hostname[HOST_NAME_LENGTH + 1];
63 	char *rem_name;
64 	char *my_name;
65 	char *my_machine_name;
66 	char *rem_machine_name;
67 	char *rem_tty;
68 	char *ptr;
69 	int name_length;
70 
71 	if (argc < 2) {
72 		fprintf(stderr,
73 		    "Usage: talk %s\n", gettext("address [terminal]"));
74 		exit(1);
75 	}
76 	if (!isatty(0)) {
77 		fprintf(stderr,
78 	gettext("Standard input must be a tty, not a pipe or a file\n"));
79 		exit(1);
80 	}
81 
82 	if (!isatty(1)) {
83 		fprintf(stderr,
84 	gettext("Standard output must be a tty, not a pipe or a file\n"));
85 		exit(1);
86 	}
87 
88 	if ((my_name = getlogin()) == NULL) {
89 	struct passwd *pass = getpwuid(getuid());
90 	if (pass != NULL)
91 		my_name = pass->pw_name;
92 	}
93 	if (my_name == NULL) {
94 		fprintf(stderr,
95 	gettext("Who are you?  You have no entry in /etc/utmp!  Aborting..\n"));
96 		exit(1);
97 	}
98 
99 	name_length = HOST_NAME_LENGTH;
100 	(void) sysinfo(SI_HOSTNAME, hostname, name_length);
101 	my_machine_name = hostname;
102 
103 	/*
104 	 * check for, and strip out, the machine name of the target
105 	 */
106 
107 	for (ptr = argv[1]; *ptr != '\0' &&
108 			 *ptr != '@' &&
109 			 *ptr != ':' &&
110 			 *ptr != '!' &&
111 			 *ptr != '.'; ptr++) {
112 	}
113 
114 	if (*ptr == '\0') {
115 
116 		/* this is a local to local talk */
117 
118 	rem_name = argv[1];
119 	rem_machine_name = my_machine_name;
120 
121 	} else {
122 
123 	if (*ptr == '@') {
124 		/* user@host */
125 		rem_name = argv[1];
126 		rem_machine_name = ptr + 1;
127 	} else {
128 		/* host.user or host!user or host:user */
129 		rem_name = ptr + 1;
130 		rem_machine_name = argv[1];
131 	}
132 	*ptr = '\0';
133 	}
134 
135 
136 	if (argc > 2) {
137 	rem_tty = argv[2];	/* tty name is arg 2 */
138 	} else {
139 	rem_tty = "";
140 	}
141 
142 	get_addrs(my_machine_name, rem_machine_name);
143 
144 	/* Load these useful values into the standard message header */
145 
146 	msg.id_num = 0;
147 
148 	strncpy(msg.l_name, my_name, NAME_SIZE);
149 	msg.l_name[NAME_SIZE - 1] = '\0';
150 
151 	strncpy(msg.r_name, rem_name, NAME_SIZE);
152 	msg.r_name[NAME_SIZE - 1] = '\0';
153 
154 	strncpy(msg.r_tty, rem_tty, TTY_SIZE);
155 	msg.r_tty[TTY_SIZE - 1] = '\0';
156 }
157