xref: /openbsd-src/usr.bin/talk/ctl_transact.c (revision a4afd6dad3fba28f80e70208181c06c482259988)
1 /*	$OpenBSD: ctl_transact.c,v 1.3 1996/06/26 05:40:20 deraadt Exp $	*/
2 /*	$NetBSD: ctl_transact.c,v 1.3 1994/12/09 02:14:12 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. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)ctl_transact.c	8.1 (Berkeley) 6/6/93";
40 #endif
41 static char rcsid[] = "$OpenBSD: ctl_transact.c,v 1.3 1996/06/26 05:40:20 deraadt Exp $";
42 #endif /* not lint */
43 
44 #include <sys/types.h>
45 #include <sys/socket.h>
46 #include <sys/time.h>
47 #include <netinet/in.h>
48 #include <protocols/talkd.h>
49 #include <errno.h>
50 #include "talk_ctl.h"
51 
52 #define CTL_WAIT 2	/* time to wait for a response, in seconds */
53 
54 /*
55  * SOCKDGRAM is unreliable, so we must repeat messages if we have
56  * not recieved an acknowledgement within a reasonable amount
57  * of time
58  */
59 ctl_transact(target, msg, type, rp)
60 	struct in_addr target;
61 	CTL_MSG msg;
62 	int type;
63 	CTL_RESPONSE *rp;
64 {
65 	int read_mask, ctl_mask, nready, cc;
66 	struct timeval wait;
67 
68 	msg.type = type;
69 	daemon_addr.sin_addr = target;
70 	daemon_addr.sin_port = daemon_port;
71 	ctl_mask = 1 << ctl_sockt;
72 
73 	/*
74 	 * Keep sending the message until a response of
75 	 * the proper type is obtained.
76 	 */
77 	do {
78 		wait.tv_sec = CTL_WAIT;
79 		wait.tv_usec = 0;
80 		/* resend message until a response is obtained */
81 		do {
82 			cc = sendto(ctl_sockt, (char *)&msg, sizeof (msg), 0,
83 			    (struct sockaddr *)&daemon_addr,
84 			    sizeof (daemon_addr));
85 			if (cc != sizeof (msg)) {
86 				if (errno == EINTR)
87 					continue;
88 				p_error("Error on write to talk daemon");
89 			}
90 			read_mask = ctl_mask;
91 			nready = select(32, &read_mask, 0, 0, &wait);
92 			if (nready < 0) {
93 				if (errno == EINTR)
94 					continue;
95 				p_error("Error waiting for daemon response");
96 			}
97 		} while (nready == 0);
98 		/*
99 		 * Keep reading while there are queued messages
100 		 * (this is not necessary, it just saves extra
101 		 * request/acknowledgements being sent)
102 		 */
103 		do {
104 			cc = recv(ctl_sockt, (char *)rp, sizeof (*rp), 0);
105 			if (cc < 0) {
106 				if (errno == EINTR)
107 					continue;
108 				p_error("Error on read from talk daemon");
109 			}
110 			read_mask = ctl_mask;
111 			/* an immediate poll */
112 			timerclear(&wait);
113 			nready = select(32, &read_mask, 0, 0, &wait);
114 		} while (nready > 0 && (rp->vers != TALK_VERSION ||
115 		    rp->type != type));
116 	} while (rp->vers != TALK_VERSION || rp->type != type);
117 	rp->id_num = ntohl(rp->id_num);
118 }
119