1 /* $NetBSD: ctl_transact.c,v 1.10 2009/04/13 23:43:36 lukem Exp $ */ 2 3 /* 4 * Copyright (c) 1983, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)ctl_transact.c 8.1 (Berkeley) 6/6/93"; 36 #endif 37 __RCSID("$NetBSD: ctl_transact.c,v 1.10 2009/04/13 23:43:36 lukem Exp $"); 38 #endif /* not lint */ 39 40 #include "talk.h" 41 #include <sys/time.h> 42 #include <errno.h> 43 #include <unistd.h> 44 #include <poll.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 received an acknowledgement within a reasonable amount 52 * of time 53 */ 54 void 55 ctl_transact(target, tmsg, type, rp) 56 struct in_addr target; 57 CTL_MSG tmsg; 58 int type; 59 CTL_RESPONSE *rp; 60 { 61 struct pollfd set[1]; 62 int nready, cc; 63 64 nready = 0; 65 tmsg.type = type; 66 daemon_addr.sin_addr = target; 67 daemon_addr.sin_port = daemon_port; 68 set[0].fd = ctl_sockt; 69 set[0].events = POLLIN; 70 71 /* 72 * Keep sending the message until a response of 73 * the proper type is obtained. 74 */ 75 do { 76 /* resend message until a response is obtained */ 77 do { 78 cc = sendto(ctl_sockt, (char *)&tmsg, sizeof (tmsg), 0, 79 (struct sockaddr *)&daemon_addr, 80 sizeof (daemon_addr)); 81 if (cc != sizeof (tmsg)) { 82 if (errno == EINTR) 83 continue; 84 p_error("Error on write to talk daemon"); 85 } 86 nready = poll(set, 1, CTL_WAIT * 1000); 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 /* an immediate poll */ 106 nready = poll(set, 1, 0); 107 } while (nready > 0 && (rp->vers != TALK_VERSION || 108 rp->type != type)); 109 } while (rp->vers != TALK_VERSION || rp->type != type); 110 rp->id_num = ntohl(rp->id_num); 111 rp->addr.sa_family = ntohs(rp->addr.sa_family); 112 } 113