xref: /illumos-gate/usr/src/cmd/cmd-inet/usr.bin/talk/ctl_transact.c (revision 41e0a469c3dbc14deb2b200f6ca6f6e00b5865d0)
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 1997 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * University Copyright- Copyright (c) 1982, 1986, 1988
32  * The Regents of the University of California
33  * All Rights Reserved
34  *
35  * University Acknowledgment- Portions of this document are derived from
36  * software developed by the University of California, Berkeley, and its
37  * contributors.
38  */
39 
40 #include "talk_ctl.h"
41 #include <sys/time.h>
42 #include <libintl.h>
43 
44 #define	CTL_WAIT	2
45 	/* the amount of time to wait for a response, in seconds */
46 
47 
48 /*
49  * SOCKDGRAM is unreliable, so we must repeat messages if we have
50  * not recieved an acknowledgement within a reasonable amount of time
51  */
52 
53 void
54 ctl_transact(target, msg, type, response)
55 struct in_addr target;
56 CTL_MSG msg;
57 int type;
58 CTL_RESPONSE *response;
59 {
60 	struct sockaddr junk;
61 	int read_mask;
62 	int ctl_mask;
63 	int nready;
64 	int cc;
65 	socklen_t junk_size;
66 	struct timeval wait;
67 
68 	wait.tv_sec = CTL_WAIT;
69 	wait.tv_usec = 0;
70 
71 	msg.type = type;
72 
73 	daemon_addr.sin_addr = target;
74 	daemon_addr.sin_port = daemon_port;
75 
76 	ctl_mask = 1 << ctl_sockt;
77 
78 	/*
79 	 * keep sending the message until a response of the right
80 	 * type is obtained
81 	 */
82 
83 	do {
84 		/* keep sending the message until a response is obtained */
85 
86 		do {
87 			cc = sendto(ctl_sockt,
88 				(char *)&msg, sizeof (CTL_MSG), 0,
89 			(struct sockaddr *)&daemon_addr, sizeof (daemon_addr));
90 
91 			if (cc != sizeof (CTL_MSG)) {
92 				if (errno == EINTR) {
93 			/* we are returning from an interupt */
94 					continue;
95 				} else {
96 					p_error(
97 				gettext("Error on write to talk daemon"));
98 				}
99 			}
100 
101 			read_mask = ctl_mask;
102 
103 			while ((nready = select(32, (fd_set *)&read_mask,
104 				0, 0, &wait)) < 0) {
105 			if (errno == EINTR) {
106 			/* we are returning from an interupt */
107 				continue;
108 			} else {
109 				p_error(
110 			gettext("Error on waiting for response from daemon"));
111 			}
112 		}
113 	} while (nready == 0);
114 
115 	/*
116 	 * keep reading while there are queued messages
117 	 * (this is not necessary, it just saves extra
118 	 * request/acknowledgements being sent)
119 	 */
120 
121 	do {
122 
123 		junk_size = (socklen_t)sizeof (junk);
124 		cc = recvfrom(ctl_sockt, (char *)response,
125 			sizeof (CTL_RESPONSE), 0, &junk, &junk_size);
126 		if (cc < 0) {
127 			if (errno == EINTR) {
128 				continue;
129 			}
130 			p_error(gettext("Error on read from talk daemon"));
131 		}
132 
133 		read_mask = ctl_mask;
134 
135 		/* an immediate poll */
136 
137 		timerclear(&wait);
138 		nready = select(32, (fd_set *)&read_mask, 0, 0, &wait);
139 
140 	} while (nready > 0 && response->type != type);
141 
142 	} while (response->type != type);
143 }
144