1 /*
2 * Copyright (c) 1983, 1993
3 * The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)ctl_transact.c 8.1 (Berkeley) 6/6/93
30 * $FreeBSD: src/usr.bin/talk/ctl_transact.c,v 1.5 1999/08/28 01:06:11 peter Exp $
31 */
32
33 #include <errno.h>
34 #include <string.h>
35 #include "talk.h"
36 #include "talk_ctl.h"
37
38 #define CTL_WAIT 2 /* time to wait for a response, in seconds */
39
40 /*
41 * SOCKDGRAM is unreliable, so we must repeat messages if we have
42 * not recieved an acknowledgement within a reasonable amount
43 * of time
44 */
45 void
ctl_transact(struct in_addr target,CTL_MSG lmsg,int type,CTL_RESPONSE * rp)46 ctl_transact(struct in_addr target, CTL_MSG lmsg, int type, CTL_RESPONSE *rp)
47 {
48 fd_set read_mask, ctl_mask;
49 int nready = 0, cc;
50 struct timeval wait;
51
52 lmsg.type = type;
53 daemon_addr.sin_addr = target;
54 daemon_addr.sin_port = daemon_port;
55 FD_ZERO(&ctl_mask);
56 FD_SET(ctl_sockt, &ctl_mask);
57
58 /*
59 * Keep sending the message until a response of
60 * the proper type is obtained.
61 */
62 do {
63 wait.tv_sec = CTL_WAIT;
64 wait.tv_usec = 0;
65 /* resend message until a response is obtained */
66 do {
67 cc = sendto(ctl_sockt, (char *)&lmsg, sizeof (lmsg), 0,
68 (struct sockaddr *)&daemon_addr,
69 sizeof (daemon_addr));
70 if (cc != sizeof (lmsg)) {
71 if (errno == EINTR)
72 continue;
73 p_error("Error on write to talk daemon");
74 }
75 read_mask = ctl_mask;
76 nready = select(32, &read_mask, 0, 0, &wait);
77 if (nready < 0) {
78 if (errno == EINTR)
79 continue;
80 p_error("Error waiting for daemon response");
81 }
82 } while (nready == 0);
83 /*
84 * Keep reading while there are queued messages
85 * (this is not necessary, it just saves extra
86 * request/acknowledgements being sent)
87 */
88 do {
89 cc = recv(ctl_sockt, (char *)rp, sizeof (*rp), 0);
90 if (cc < 0) {
91 if (errno == EINTR)
92 continue;
93 p_error("Error on read from talk daemon");
94 }
95 read_mask = ctl_mask;
96 /* an immediate poll */
97 timerclear(&wait);
98 nready = select(32, &read_mask, 0, 0, &wait);
99 } while (nready > 0 && (rp->vers != TALK_VERSION ||
100 rp->type != type));
101 } while (rp->vers != TALK_VERSION || rp->type != type);
102 rp->id_num = ntohl(rp->id_num);
103 rp->addr.sa_family = ntohs(rp->addr.sa_family);
104 }
105