/*      $NetBSD: look_up.c,v 1.8 2012/03/20 20:34:59 matt 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 <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)look_up.c   8.1 (Berkeley) 6/6/93";
#endif
__RCSID("$NetBSD: look_up.c,v 1.8 2012/03/20 20:34:59 matt Exp $");
#endif /* not lint */

#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;
       CTL_RESPONSE *rp = &response;
       struct sockaddr addr;

       /* 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 talkd_sockaddr *)(void *)&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");

               (void)memcpy(&addr, &rp->addr.sa_family, sizeof(addr));
               addr.sa_family = rp->addr.sa_family;
               addr.sa_len = sizeof(addr);

               errno = 0;
               if (connect(sockt, &addr, sizeof(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'
*/
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);
       }
}