1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 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 33 #ifndef lint 34 static const char sccsid[] = "@(#)ctl_transact.c 8.1 (Berkeley) 6/6/93"; 35 #endif 36 37 #include <arpa/inet.h> 38 39 #include <errno.h> 40 #include <poll.h> 41 42 #include "talk.h" 43 #include "talk_ctl.h" 44 45 #define CTL_WAIT 2 /* time to wait for a response, in seconds */ 46 47 /* 48 * SOCKDGRAM is unreliable, so we must repeat messages if we have 49 * not received an acknowledgement within a reasonable amount 50 * of time 51 */ 52 void 53 ctl_transact(struct in_addr target, CTL_MSG lmsg, int type, CTL_RESPONSE *rp) 54 { 55 struct pollfd pfd[1]; 56 int nready = 0, cc; 57 58 lmsg.type = type; 59 daemon_addr.sin_addr = target; 60 daemon_addr.sin_port = daemon_port; 61 pfd[0].fd = ctl_sockt; 62 pfd[0].events = POLLIN; 63 64 /* 65 * Keep sending the message until a response of 66 * the proper type is obtained. 67 */ 68 do { 69 /* resend message until a response is obtained */ 70 do { 71 cc = sendto(ctl_sockt, (char *)&lmsg, sizeof (lmsg), 0, 72 (struct sockaddr *)&daemon_addr, 73 sizeof (daemon_addr)); 74 if (cc != sizeof (lmsg)) { 75 if (errno == EINTR) 76 continue; 77 p_error("Error on write to talk daemon"); 78 } 79 nready = poll(pfd, 1, CTL_WAIT * 1000); 80 if (nready < 0) { 81 if (errno == EINTR) 82 continue; 83 p_error("Error waiting for daemon response"); 84 } 85 } while (nready == 0); 86 /* 87 * Keep reading while there are queued messages 88 * (this is not necessary, it just saves extra 89 * request/acknowledgements being sent) 90 */ 91 do { 92 cc = recv(ctl_sockt, (char *)rp, sizeof (*rp), 0); 93 if (cc < 0) { 94 if (errno == EINTR) 95 continue; 96 p_error("Error on read from talk daemon"); 97 } 98 nready = poll(pfd, 1, 0); 99 } while (nready > 0 && (rp->vers != TALK_VERSION || 100 rp->type != type)); 101 } while (rp->vers != TALK_VERSION || rp->type != type); 102 rp->id_num = ntohl(rp->id_num); 103 rp->addr.sa_family = ntohs(rp->addr.sa_family); 104 } 105