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 * @(#)look_up.c 8.1 (Berkeley) 6/6/93 30 * $FreeBSD: src/usr.bin/talk/look_up.c,v 1.5 1999/08/28 01:06:14 peter Exp $ 31 */ 32 33 #include <sys/param.h> 34 #include <sys/socket.h> 35 #include <protocols/talkd.h> 36 #include <errno.h> 37 #include "talk_ctl.h" 38 #include "talk.h" 39 40 /* 41 * See if the local daemon has an invitation for us. 42 */ 43 int 44 check_local(void) 45 { 46 CTL_RESPONSE response; 47 CTL_RESPONSE *rp = &response; 48 49 /* the rest of msg was set up in get_names */ 50 #ifdef MSG_EOR 51 /* copy new style sockaddr to old, swap family (short in old) */ 52 msg.ctl_addr = *(struct osockaddr *)&ctl_addr; 53 msg.ctl_addr.sa_family = htons(ctl_addr.sin_family); 54 #else 55 msg.ctl_addr = *(struct sockaddr *)&ctl_addr; 56 #endif 57 /* must be initiating a talk */ 58 if (!look_for_invite(rp)) 59 return (0); 60 /* 61 * There was an invitation waiting for us, 62 * so connect with the other (hopefully waiting) party 63 */ 64 current_state = "Waiting to connect with caller"; 65 do { 66 if (rp->addr.sa_family != AF_INET) 67 p_error("Response uses invalid network address"); 68 errno = 0; 69 if (connect(sockt, 70 (struct sockaddr *)&rp->addr, sizeof (rp->addr)) != -1) 71 return (1); 72 } while (errno == EINTR); 73 if (errno == ECONNREFUSED) { 74 /* 75 * The caller gave up, but his invitation somehow 76 * was not cleared. Clear it and initiate an 77 * invitation. (We know there are no newer invitations, 78 * the talkd works LIFO.) 79 */ 80 ctl_transact(his_machine_addr, msg, DELETE, rp); 81 close(sockt); 82 open_sockt(); 83 return (0); 84 } 85 p_error("Unable to connect with initiator"); 86 /*NOTREACHED*/ 87 return (0); 88 } 89 90 /* 91 * Look for an invitation on 'machine' 92 */ 93 int 94 look_for_invite(CTL_RESPONSE *rp) 95 { 96 current_state = "Checking for invitation on caller's machine"; 97 ctl_transact(his_machine_addr, msg, LOOK_UP, rp); 98 /* the switch is for later options, such as multiple invitations */ 99 switch (rp->answer) { 100 101 case SUCCESS: 102 msg.id_num = htonl(rp->id_num); 103 return (1); 104 105 default: 106 /* there wasn't an invitation waiting for us */ 107 return (0); 108 } 109 } 110