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[] = "from: @(#)ctl_transact.c 5.8 (Berkeley) 3/1/91";*/ 36 static char rcsid[] = "$Id: ctl_transact.c,v 1.2 1993/08/01 18:07:54 mycroft Exp $"; 37 #endif /* not lint */ 38 39 #include <sys/types.h> 40 #include <sys/socket.h> 41 #include <sys/time.h> 42 #include <netinet/in.h> 43 #include <protocols/talkd.h> 44 #include <errno.h> 45 #include "talk_ctl.h" 46 47 #define CTL_WAIT 2 /* time to wait for a response, in seconds */ 48 49 /* 50 * SOCKDGRAM is unreliable, so we must repeat messages if we have 51 * not recieved an acknowledgement within a reasonable amount 52 * of time 53 */ 54 ctl_transact(target, msg, type, rp) 55 struct in_addr target; 56 CTL_MSG msg; 57 int type; 58 CTL_RESPONSE *rp; 59 { 60 int read_mask, ctl_mask, nready, cc; 61 struct timeval wait; 62 63 msg.type = type; 64 daemon_addr.sin_addr = target; 65 daemon_addr.sin_port = daemon_port; 66 ctl_mask = 1 << ctl_sockt; 67 68 /* 69 * Keep sending the message until a response of 70 * the proper type is obtained. 71 */ 72 do { 73 wait.tv_sec = CTL_WAIT; 74 wait.tv_usec = 0; 75 /* resend message until a response is obtained */ 76 do { 77 cc = sendto(ctl_sockt, (char *)&msg, sizeof (msg), 0, 78 (struct sockaddr *)&daemon_addr, 79 sizeof (daemon_addr)); 80 if (cc != sizeof (msg)) { 81 if (errno == EINTR) 82 continue; 83 p_error("Error on write to talk daemon"); 84 } 85 read_mask = ctl_mask; 86 nready = select(32, &read_mask, 0, 0, &wait); 87 if (nready < 0) { 88 if (errno == EINTR) 89 continue; 90 p_error("Error waiting for daemon response"); 91 } 92 } while (nready == 0); 93 /* 94 * Keep reading while there are queued messages 95 * (this is not necessary, it just saves extra 96 * request/acknowledgements being sent) 97 */ 98 do { 99 cc = recv(ctl_sockt, (char *)rp, sizeof (*rp), 0); 100 if (cc < 0) { 101 if (errno == EINTR) 102 continue; 103 p_error("Error on read from talk daemon"); 104 } 105 read_mask = ctl_mask; 106 /* an immediate poll */ 107 timerclear(&wait); 108 nready = select(32, &read_mask, 0, 0, &wait); 109 } while (nready > 0 && (rp->vers != TALK_VERSION || 110 rp->type != type)); 111 } while (rp->vers != TALK_VERSION || rp->type != type); 112 rp->id_num = ntohl(rp->id_num); 113 rp->addr.sa_family = ntohs(rp->addr.sa_family); 114 } 115