1 /* 2 * Copyright (c) 1983, 1993 3 * The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 32 __FBSDID("$FreeBSD$"); 33 34 #ifndef lint 35 static const char sccsid[] = "@(#)ctl_transact.c 8.1 (Berkeley) 6/6/93"; 36 #endif 37 38 #include <arpa/inet.h> 39 40 #include <errno.h> 41 #include <poll.h> 42 43 #include "talk.h" 44 #include "talk_ctl.h" 45 46 #define CTL_WAIT 2 /* time to wait for a response, in seconds */ 47 48 /* 49 * SOCKDGRAM is unreliable, so we must repeat messages if we have 50 * not received an acknowledgement within a reasonable amount 51 * of time 52 */ 53 void 54 ctl_transact(struct in_addr target, CTL_MSG lmsg, int type, CTL_RESPONSE *rp) 55 { 56 struct pollfd pfd[1]; 57 int nready = 0, cc; 58 59 lmsg.type = type; 60 daemon_addr.sin_addr = target; 61 daemon_addr.sin_port = daemon_port; 62 pfd[0].fd = ctl_sockt; 63 pfd[0].events = POLLIN; 64 65 /* 66 * Keep sending the message until a response of 67 * the proper type is obtained. 68 */ 69 do { 70 /* resend message until a response is obtained */ 71 do { 72 cc = sendto(ctl_sockt, (char *)&lmsg, sizeof (lmsg), 0, 73 (struct sockaddr *)&daemon_addr, 74 sizeof (daemon_addr)); 75 if (cc != sizeof (lmsg)) { 76 if (errno == EINTR) 77 continue; 78 p_error("Error on write to talk daemon"); 79 } 80 nready = poll(pfd, 1, CTL_WAIT * 1000); 81 if (nready < 0) { 82 if (errno == EINTR) 83 continue; 84 p_error("Error waiting for daemon response"); 85 } 86 } while (nready == 0); 87 /* 88 * Keep reading while there are queued messages 89 * (this is not necessary, it just saves extra 90 * request/acknowledgements being sent) 91 */ 92 do { 93 cc = recv(ctl_sockt, (char *)rp, sizeof (*rp), 0); 94 if (cc < 0) { 95 if (errno == EINTR) 96 continue; 97 p_error("Error on read from talk daemon"); 98 } 99 nready = poll(pfd, 1, 0); 100 } while (nready > 0 && (rp->vers != TALK_VERSION || 101 rp->type != type)); 102 } while (rp->vers != TALK_VERSION || rp->type != type); 103 rp->id_num = ntohl(rp->id_num); 104 rp->addr.sa_family = ntohs(rp->addr.sa_family); 105 } 106