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/* $OpenBSD: look_up.c,v 1.12 2010/08/12 23:31:29 tedu Exp $ */
/* $NetBSD: look_up.c,v 1.3 1994/12/09 02:14:21 jtc Exp $ */
/*
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "talk.h"
#include <errno.h>
#include <unistd.h>
#include "talk_ctl.h"
/*
* See if the local daemon has an invitation for us.
*/
int
check_local(void)
{
CTL_RESPONSE response;
/* the rest of msg was set up in get_names */
#ifdef MSG_EOR
/* copy new style sockaddr to old, swap family (short in old) */
msg.ctl_addr = *(struct osockaddr *)&ctl_addr;
msg.ctl_addr.sa_family = htons(ctl_addr.sin_family);
#else
msg.ctl_addr = *(struct sockaddr *)&ctl_addr;
#endif
/* must be initiating a talk */
if (!look_for_invite(&response))
return (0);
/*
* There was an invitation waiting for us,
* so connect with the other (hopefully waiting) party
*/
current_state = "Waiting to connect with caller";
do {
if (ntohs(response.addr.sa_family) != AF_INET)
quit("Response uses invalid network address", 1);
errno = 0;
if (connect(sockt, (struct sockaddr *)&response.addr,
sizeof (response.addr)) != -1)
return (1);
} while (errno == EINTR);
if (errno == ECONNREFUSED) {
/*
* The caller gave up, but his invitation somehow
* was not cleared. Clear it and initiate an
* invitation. (We know there are no newer invitations,
* the talkd works LIFO.)
*/
ctl_transact(his_machine_addr, msg, DELETE, &response);
close(sockt);
open_sockt();
return (0);
}
quit("Unable to connect with initiator", 1);
/*NOTREACHED*/
return (0);
}
/*
* Look for an invitation on 'machine'
*/
int
look_for_invite(CTL_RESPONSE *rp)
{
current_state = "Checking for invitation on caller's machine";
ctl_transact(his_machine_addr, msg, LOOK_UP, rp);
/* the switch is for later options, such as multiple invitations */
switch (rp->answer) {
case SUCCESS:
msg.id_num = htonl(rp->id_num);
return (1);
default:
/* there wasn't an invitation waiting for us */
return (0);
}
}
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