1 /* $NetBSD: ctl_transact.c,v 1.8 2002/09/23 12:48:03 mycroft 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)ctl_transact.c 8.1 (Berkeley) 6/6/93"; 40 #endif 41 __RCSID("$NetBSD: ctl_transact.c,v 1.8 2002/09/23 12:48:03 mycroft Exp $"); 42 #endif /* not lint */ 43 44 #include "talk.h" 45 #include <sys/time.h> 46 #include <errno.h> 47 #include <unistd.h> 48 #include <poll.h> 49 #include "talk_ctl.h" 50 51 #define CTL_WAIT 2 /* time to wait for a response, in seconds */ 52 53 /* 54 * SOCKDGRAM is unreliable, so we must repeat messages if we have 55 * not received an acknowledgement within a reasonable amount 56 * of time 57 */ 58 void 59 ctl_transact(target, msg, type, rp) 60 struct in_addr target; 61 CTL_MSG msg; 62 int type; 63 CTL_RESPONSE *rp; 64 { 65 struct pollfd set[1]; 66 int nready, cc; 67 68 nready = 0; 69 msg.type = type; 70 daemon_addr.sin_addr = target; 71 daemon_addr.sin_port = daemon_port; 72 set[0].fd = ctl_sockt; 73 set[0].events = POLLIN; 74 75 /* 76 * Keep sending the message until a response of 77 * the proper type is obtained. 78 */ 79 do { 80 /* resend message until a response is obtained */ 81 do { 82 cc = sendto(ctl_sockt, (char *)&msg, sizeof (msg), 0, 83 (struct sockaddr *)&daemon_addr, 84 sizeof (daemon_addr)); 85 if (cc != sizeof (msg)) { 86 if (errno == EINTR) 87 continue; 88 p_error("Error on write to talk daemon"); 89 } 90 nready = poll(set, 1, CTL_WAIT * 1000); 91 if (nready < 0) { 92 if (errno == EINTR) 93 continue; 94 p_error("Error waiting for daemon response"); 95 } 96 } while (nready == 0); 97 /* 98 * Keep reading while there are queued messages 99 * (this is not necessary, it just saves extra 100 * request/acknowledgements being sent) 101 */ 102 do { 103 cc = recv(ctl_sockt, (char *)rp, sizeof (*rp), 0); 104 if (cc < 0) { 105 if (errno == EINTR) 106 continue; 107 p_error("Error on read from talk daemon"); 108 } 109 /* an immediate poll */ 110 nready = poll(set, 1, 0); 111 } while (nready > 0 && (rp->vers != TALK_VERSION || 112 rp->type != type)); 113 } while (rp->vers != TALK_VERSION || rp->type != type); 114 rp->id_num = ntohl(rp->id_num); 115 rp->addr.sa_family = ntohs(rp->addr.sa_family); 116 } 117