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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 #if 0 36 static char sccsid[] = "@(#)look_up.c 8.1 (Berkeley) 6/6/93"; 37 #endif 38 static const char rcsid[] = 39 "$Id$"; 40 #endif /* not lint */ 41 42 #include <errno.h> 43 #include <sys/types.h> 44 #include <sys/socket.h> 45 #include <protocols/talkd.h> 46 #include "talk_ctl.h" 47 #include "talk.h" 48 49 /* 50 * See if the local daemon has an invitation for us. 51 */ 52 int 53 check_local() 54 { 55 CTL_RESPONSE response; 56 register CTL_RESPONSE *rp = &response; 57 58 /* the rest of msg was set up in get_names */ 59 #ifdef MSG_EOR 60 /* copy new style sockaddr to old, swap family (short in old) */ 61 msg.ctl_addr = *(struct osockaddr *)&ctl_addr; 62 msg.ctl_addr.sa_family = htons(ctl_addr.sin_family); 63 #else 64 msg.ctl_addr = *(struct sockaddr *)&ctl_addr; 65 #endif 66 /* must be initiating a talk */ 67 if (!look_for_invite(rp)) 68 return (0); 69 /* 70 * There was an invitation waiting for us, 71 * so connect with the other (hopefully waiting) party 72 */ 73 current_state = "Waiting to connect with caller"; 74 do { 75 if (rp->addr.sa_family != AF_INET) 76 p_error("Response uses invalid network address"); 77 errno = 0; 78 if (connect(sockt, 79 (struct sockaddr *)&rp->addr, sizeof (rp->addr)) != -1) 80 return (1); 81 } while (errno == EINTR); 82 if (errno == ECONNREFUSED) { 83 /* 84 * The caller gave up, but his invitation somehow 85 * was not cleared. Clear it and initiate an 86 * invitation. (We know there are no newer invitations, 87 * the talkd works LIFO.) 88 */ 89 ctl_transact(his_machine_addr, msg, DELETE, rp); 90 close(sockt); 91 open_sockt(); 92 return (0); 93 } 94 p_error("Unable to connect with initiator"); 95 /*NOTREACHED*/ 96 return (0); 97 } 98 99 /* 100 * Look for an invitation on 'machine' 101 */ 102 int 103 look_for_invite(rp) 104 CTL_RESPONSE *rp; 105 { 106 struct in_addr machine_addr; 107 108 current_state = "Checking for invitation on caller's machine"; 109 ctl_transact(his_machine_addr, msg, LOOK_UP, rp); 110 /* the switch is for later options, such as multiple invitations */ 111 switch (rp->answer) { 112 113 case SUCCESS: 114 msg.id_num = htonl(rp->id_num); 115 return (1); 116 117 default: 118 /* there wasn't an invitation waiting for us */ 119 return (0); 120 } 121 } 122