/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * 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/types.h>
#include <sys/socket.h>
#include <protocols/talkd.h>

#include <errno.h>
#include <string.h>
#include <unistd.h>

#include "talk_ctl.h"
#include "talk.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 */
        /* copy new style sockaddr to old, swap family (short in old) */
        msg.ctl_addr = *(struct tsockaddr *)&ctl_addr;
        msg.ctl_addr.sa_family = htons(ctl_addr.sin_family);
        /* 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);
        }
}