xref: /netbsd-src/usr.bin/talk/ctl_transact.c (revision ce0bb6e8d2e560ecacbe865a848624f94498063b)
1 /*	$NetBSD: ctl_transact.c,v 1.3 1994/12/09 02:14:12 jtc 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 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)ctl_transact.c	8.1 (Berkeley) 6/6/93";
39 #endif
40 static char rcsid[] = "$NetBSD: ctl_transact.c,v 1.3 1994/12/09 02:14:12 jtc Exp $";
41 #endif /* not lint */
42 
43 #include <sys/types.h>
44 #include <sys/socket.h>
45 #include <sys/time.h>
46 #include <netinet/in.h>
47 #include <protocols/talkd.h>
48 #include <errno.h>
49 #include "talk_ctl.h"
50 
51 #define CTL_WAIT 2	/* time to wait for a response, in seconds */
52 
53 /*
54  * SOCKDGRAM is unreliable, so we must repeat messages if we have
55  * not recieved an acknowledgement within a reasonable amount
56  * of time
57  */
58 ctl_transact(target, msg, type, rp)
59 	struct in_addr target;
60 	CTL_MSG msg;
61 	int type;
62 	CTL_RESPONSE *rp;
63 {
64 	int read_mask, ctl_mask, nready, cc;
65 	struct timeval wait;
66 
67 	msg.type = type;
68 	daemon_addr.sin_addr = target;
69 	daemon_addr.sin_port = daemon_port;
70 	ctl_mask = 1 << ctl_sockt;
71 
72 	/*
73 	 * Keep sending the message until a response of
74 	 * the proper type is obtained.
75 	 */
76 	do {
77 		wait.tv_sec = CTL_WAIT;
78 		wait.tv_usec = 0;
79 		/* resend message until a response is obtained */
80 		do {
81 			cc = sendto(ctl_sockt, (char *)&msg, sizeof (msg), 0,
82 			    (struct sockaddr *)&daemon_addr,
83 			    sizeof (daemon_addr));
84 			if (cc != sizeof (msg)) {
85 				if (errno == EINTR)
86 					continue;
87 				p_error("Error on write to talk daemon");
88 			}
89 			read_mask = ctl_mask;
90 			nready = select(32, &read_mask, 0, 0, &wait);
91 			if (nready < 0) {
92 				if (errno == EINTR)
93 					continue;
94 				p_error("Error waiting for daemon response");
95 			}
96 		} while (nready == 0);
97 		/*
98 		 * Keep reading while there are queued messages
99 		 * (this is not necessary, it just saves extra
100 		 * request/acknowledgements being sent)
101 		 */
102 		do {
103 			cc = recv(ctl_sockt, (char *)rp, sizeof (*rp), 0);
104 			if (cc < 0) {
105 				if (errno == EINTR)
106 					continue;
107 				p_error("Error on read from talk daemon");
108 			}
109 			read_mask = ctl_mask;
110 			/* an immediate poll */
111 			timerclear(&wait);
112 			nready = select(32, &read_mask, 0, 0, &wait);
113 		} while (nready > 0 && (rp->vers != TALK_VERSION ||
114 		    rp->type != type));
115 	} while (rp->vers != TALK_VERSION || rp->type != type);
116 	rp->id_num = ntohl(rp->id_num);
117 	rp->addr.sa_family = ntohs(rp->addr.sa_family);
118 }
119