ctl_transact.c revision 1.1 1 /*
2 * Copyright (c) 1983 Regents of the University of California.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #ifndef lint
35 static char sccsid[] = "@(#)ctl_transact.c 5.8 (Berkeley) 3/1/91";
36 #endif /* not lint */
37
38 #include <sys/types.h>
39 #include <sys/socket.h>
40 #include <sys/time.h>
41 #include <netinet/in.h>
42 #include <protocols/talkd.h>
43 #include <errno.h>
44 #include "talk_ctl.h"
45
46 #define CTL_WAIT 2 /* time to wait for a response, in seconds */
47
48 /*
49 * SOCKDGRAM is unreliable, so we must repeat messages if we have
50 * not recieved an acknowledgement within a reasonable amount
51 * of time
52 */
53 ctl_transact(target, msg, type, rp)
54 struct in_addr target;
55 CTL_MSG msg;
56 int type;
57 CTL_RESPONSE *rp;
58 {
59 int read_mask, ctl_mask, nready, cc;
60 struct timeval wait;
61
62 msg.type = type;
63 daemon_addr.sin_addr = target;
64 daemon_addr.sin_port = daemon_port;
65 ctl_mask = 1 << ctl_sockt;
66
67 /*
68 * Keep sending the message until a response of
69 * the proper type is obtained.
70 */
71 do {
72 wait.tv_sec = CTL_WAIT;
73 wait.tv_usec = 0;
74 /* resend message until a response is obtained */
75 do {
76 cc = sendto(ctl_sockt, (char *)&msg, sizeof (msg), 0,
77 (struct sockaddr *)&daemon_addr,
78 sizeof (daemon_addr));
79 if (cc != sizeof (msg)) {
80 if (errno == EINTR)
81 continue;
82 p_error("Error on write to talk daemon");
83 }
84 read_mask = ctl_mask;
85 nready = select(32, &read_mask, 0, 0, &wait);
86 if (nready < 0) {
87 if (errno == EINTR)
88 continue;
89 p_error("Error waiting for daemon response");
90 }
91 } while (nready == 0);
92 /*
93 * Keep reading while there are queued messages
94 * (this is not necessary, it just saves extra
95 * request/acknowledgements being sent)
96 */
97 do {
98 cc = recv(ctl_sockt, (char *)rp, sizeof (*rp), 0);
99 if (cc < 0) {
100 if (errno == EINTR)
101 continue;
102 p_error("Error on read from talk daemon");
103 }
104 read_mask = ctl_mask;
105 /* an immediate poll */
106 timerclear(&wait);
107 nready = select(32, &read_mask, 0, 0, &wait);
108 } while (nready > 0 && (rp->vers != TALK_VERSION ||
109 rp->type != type));
110 } while (rp->vers != TALK_VERSION || rp->type != type);
111 rp->id_num = ntohl(rp->id_num);
112 rp->addr.sa_family = ntohs(rp->addr.sa_family);
113 }
114