xref: /netbsd-src/libexec/talkd/talkd.c (revision 2a399c6883d870daece976daec6ffa7bb7f934ce)
1 /*	$NetBSD: talkd.c,v 1.7 1997/06/29 19:19:15 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 __COPYRIGHT("@(#) Copyright (c) 1983, 1993\n\
39 	The Regents of the University of California.  All rights reserved.\n");
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)talkd.c	8.1 (Berkeley) 6/4/93";
45 #else
46 __RCSID("$NetBSD: talkd.c,v 1.7 1997/06/29 19:19:15 christos Exp $");
47 #endif
48 #endif /* not lint */
49 
50 /*
51  * The top level of the daemon, the format is heavily borrowed
52  * from rwhod.c. Basically: find out who and where you are;
53  * disconnect all descriptors and ttys, and then endless
54  * loop on waiting for and processing requests
55  */
56 #include <sys/types.h>
57 #include <sys/socket.h>
58 #include <sys/param.h>
59 
60 #include <protocols/talkd.h>
61 #include <signal.h>
62 #include <syslog.h>
63 #include <time.h>
64 #include <errno.h>
65 #include <unistd.h>
66 #include <stdio.h>
67 #include <stdlib.h>
68 #include <string.h>
69 #include <paths.h>
70 #include "extern.h"
71 
72 CTL_MSG		request;
73 CTL_RESPONSE	response;
74 
75 int	sockt = STDIN_FILENO;
76 int	debug = 0;
77 long	lastmsgtime;
78 
79 char	hostname[MAXHOSTNAMELEN + 1];
80 
81 #define TIMEOUT 30
82 #define MAXIDLE 120
83 
84 static void timeout __P((int));
85 int	main __P((int, char *[]));
86 
87 int
88 main(argc, argv)
89 	int argc;
90 	char *argv[];
91 {
92 	CTL_MSG *mp = &request;
93 	int cc;
94 
95 	openlog("talkd", LOG_PID, LOG_DAEMON);
96 	if (gethostname(hostname, sizeof (hostname) - 1) < 0) {
97 		syslog(LOG_ERR, "gethostname: %m");
98 		_exit(1);
99 	}
100 	hostname[MAXHOSTNAMELEN] = '\0';  /* ensure null termination */
101 	if (chdir(_PATH_DEV) < 0) {
102 		syslog(LOG_ERR, "chdir: %s: %m", _PATH_DEV);
103 		_exit(1);
104 	}
105 	if (argc > 1 && strcmp(argv[1], "-d") == 0)
106 		debug = 1;
107 	signal(SIGALRM, timeout);
108 	alarm(TIMEOUT);
109 	for (;;) {
110 		extern int errno;
111 
112 		cc = recv(0, (char *)mp, sizeof (*mp), 0);
113 		if (cc != sizeof (*mp)) {
114 			if (cc < 0 && errno != EINTR)
115 				syslog(LOG_WARNING, "recv: %m");
116 			continue;
117 		}
118 		lastmsgtime = time(0);
119 		process_request(mp, &response);
120 		/* can block here, is this what I want? */
121 		cc = sendto(sockt, (char *)&response,
122 		    sizeof (response), 0, (struct sockaddr *)&mp->ctl_addr,
123 		    sizeof (mp->ctl_addr));
124 		if (cc != sizeof (response))
125 			syslog(LOG_WARNING, "sendto: %m");
126 	}
127 }
128 
129 void
130 timeout(n)
131 	int n;
132 {
133 
134 	if (time(0) - lastmsgtime >= MAXIDLE)
135 		_exit(0);
136 	alarm(TIMEOUT);
137 }
138