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/*
* Copyright (c) 1983 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
/*
* From: @(#)look_up.c 5.7 (Berkeley) 3/1/91
*/
char lu_rcsid[] =
"$Id: look_up.c,v 1.4 1996/12/29 17:07:41 dholland Exp $";
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <unistd.h>
#include <errno.h>
#include "talk.h"
#include "talk_ctl.h"
static int look_for_invite(CTL_RESPONSE *rp);
/*
* See if the local daemon has an invitation for us.
*/
int
check_local(void)
{
CTL_RESPONSE response;
register CTL_RESPONSE *rp = &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(rp))
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 (rp->addr.sa_family != AF_INET)
p_error("Response uses invalid network address");
errno = 0;
if (connect(sockt,
(struct sockaddr *)&rp->addr, sizeof (rp->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, rp);
close(sockt);
open_sockt();
return 0;
}
p_error("Unable to connect with initiator");
/*NOTREACHED*/
return 0;
}
/*
* Look for an invitation on 'machine'
*/
static int
look_for_invite(CTL_RESPONSE *rp)
{
/* struct in_addr machine_addr; */
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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