1 /* $OpenBSD: ctl_transact.c,v 1.12 2010/08/12 23:31:29 tedu Exp $ */ 2 /* $NetBSD: ctl_transact.c,v 1.3 1994/12/09 02:14:12 jtc Exp $ */ 3 4 /* 5 * Copyright (c) 1983, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include "talk.h" 34 #include <sys/time.h> 35 #include <errno.h> 36 #include <unistd.h> 37 #include <poll.h> 38 #include "talk_ctl.h" 39 40 #define CTL_WAIT 2 /* time to wait for a response, in seconds */ 41 42 /* 43 * SOCKDGRAM is unreliable, so we must repeat messages if we have 44 * not received an acknowledgement within a reasonable amount 45 * of time 46 */ 47 void 48 ctl_transact(struct in_addr target, CTL_MSG msg, int type, CTL_RESPONSE *rp) 49 { 50 struct pollfd pfd[1]; 51 int nready, cc; 52 53 msg.type = type; 54 daemon_addr.sin_addr = target; 55 daemon_addr.sin_port = daemon_port; 56 pfd[0].fd = ctl_sockt; 57 pfd[0].events = POLLIN; 58 59 /* 60 * Keep sending the message until a response of 61 * the proper type is obtained. 62 */ 63 do { 64 /* resend message until a response is obtained */ 65 do { 66 cc = sendto(ctl_sockt, (char *)&msg, sizeof (msg), 0, 67 (struct sockaddr *)&daemon_addr, 68 sizeof (daemon_addr)); 69 if (cc != sizeof (msg)) { 70 if (errno == EINTR) 71 continue; 72 quit("Error on write to talk daemon", 1); 73 } 74 nready = poll(pfd, 1, CTL_WAIT * 1000); 75 if (nready < 0) { 76 if (errno == EINTR) 77 continue; 78 quit("Error waiting for daemon response", 1); 79 } 80 } while (nready == 0); 81 /* 82 * Keep reading while there are queued messages 83 * (this is not necessary, it just saves extra 84 * request/acknowledgements being sent) 85 */ 86 do { 87 cc = recv(ctl_sockt, (char *)rp, sizeof (*rp), 0); 88 if (cc < 0) { 89 if (errno == EINTR) 90 continue; 91 quit("Error on read from talk daemon", 1); 92 } 93 nready = poll(pfd, 1, 0); 94 } while (nready > 0 && (rp->vers != TALK_VERSION || 95 rp->type != type)); 96 } while (rp->vers != TALK_VERSION || rp->type != type); 97 rp->id_num = ntohl(rp->id_num); 98 } 99