usr/src/cmd/cmd-inet/usr.bin/talk/ctl_transact.c

   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 #pragma ident   "%Z%%M% %I%     %E% SMI"
  41
  42 #include "talk_ctl.h"
  43 #include <sys/time.h>
  44 #include <libintl.h>
  45
  46 #define CTL_WAIT        2
  47         /* the amount of time to wait for a response, in seconds */
  48
  49
  50 /*
  51  * SOCKDGRAM is unreliable, so we must repeat messages if we have
  52  * not recieved an acknowledgement within a reasonable amount of time
  53  */
  54
  55 void
  56 ctl_transact(target, msg, type, response)
  57 struct in_addr target;
  58 CTL_MSG msg;
  59 int type;
  60 CTL_RESPONSE *response;
  61 {
  62         struct sockaddr junk;
  63         int read_mask;
  64         int ctl_mask;
  65         int nready;
  66         int cc;
  67         socklen_t junk_size;
  68         struct timeval wait;
  69
  70         wait.tv_sec = CTL_WAIT;
  71         wait.tv_usec = 0;
  72
  73         msg.type = type;
  74
  75         daemon_addr.sin_addr = target;
  76         daemon_addr.sin_port = daemon_port;
  77
  78         ctl_mask = 1 << ctl_sockt;
  79
  80         /*
  81          * keep sending the message until a response of the right
  82          * type is obtained
  83          */
  84
  85         do {
  86                 /* keep sending the message until a response is obtained */
  87
  88                 do {
  89                         cc = sendto(ctl_sockt,
  90                                 (char *)&msg, sizeof (CTL_MSG), 0,
  91                         (struct sockaddr *)&daemon_addr, sizeof (daemon_addr));
  92
  93                         if (cc != sizeof (CTL_MSG)) {
  94                                 if (errno == EINTR) {
  95                         /* we are returning from an interupt */
  96                                         continue;
  97                                 } else {
  98                                         p_error(
  99                                 gettext("Error on write to talk daemon"));
 100                                 }
 101                         }
 102
 103                         read_mask = ctl_mask;
 104
 105                         while ((nready = select(32, (fd_set *)&read_mask,
 106                                 0, 0, &wait)) < 0) {
 107                         if (errno == EINTR) {
 108                         /* we are returning from an interupt */
 109                                 continue;
 110                         } else {
 111                                 p_error(
 112                         gettext("Error on waiting for response from daemon"));
 113                         }
 114                 }
 115         } while (nready == 0);
 116
 117         /*
 118          * keep reading while there are queued messages
 119          * (this is not necessary, it just saves extra
 120          * request/acknowledgements being sent)
 121          */
 122
 123         do {
 124
 125                 junk_size = (socklen_t)sizeof (junk);
 126                 cc = recvfrom(ctl_sockt, (char *)response,
 127                         sizeof (CTL_RESPONSE), 0, &junk, &junk_size);
 128                 if (cc < 0) {
 129                         if (errno == EINTR) {
 130                                 continue;
 131                         }
 132                         p_error(gettext("Error on read from talk daemon"));
 133                 }
 134
 135                 read_mask = ctl_mask;
 136
 137                 /* an immediate poll */
 138
 139                 timerclear(&wait);
 140                 nready = select(32, (fd_set *)&read_mask, 0, 0, &wait);
 141
 142         } while (nready > 0 && response->type != type);
 143
 144         } while (response->type != type);
 145 }