xref: /openbsd-src/usr.bin/talk/get_names.c (revision 8d6884437550829c4e2b7b4e92288a52f1b1c398)
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 
44 extern	CTL_MSG msg;
45 
46 /*
47  * Determine the local and remote user, tty, and machines
48  */
49 void
get_names(int argc,char * argv[])50 get_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