usr.bin/talk/ctl_transact.c

	ctl_transact.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/*    All Rights Reserved   */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include "talk_ctl.h"
#include <sys/time.h>
#include <libintl.h>

#define CTL_WAIT    2
    /* the amount of time to wait for a response, in seconds */


/*
 * SOCKDGRAM is unreliable, so we must repeat messages if we have
 * not recieved an acknowledgement within a reasonable amount of time
 */

void
ctl_transact(target, msg, type, response)
struct in_addr target;
CTL_MSG msg;
int type;
CTL_RESPONSE *response;
{
    struct sockaddr junk;
    int read_mask;
    int ctl_mask;
    int nready;
    int cc;
    socklen_t junk_size;
    struct timeval wait;

    wait.tv_sec = CTL_WAIT;
    wait.tv_usec = 0;

    msg.type = type;

    daemon_addr.sin_addr = target;
    daemon_addr.sin_port = daemon_port;

    ctl_mask = 1 << ctl_sockt;

    /*
     * keep sending the message until a response of the right
     * type is obtained
     */

    do {
        /* keep sending the message until a response is obtained */

        do {
            cc = sendto(ctl_sockt,
                (char *)&msg, sizeof (CTL_MSG), 0,
            (struct sockaddr *)&daemon_addr, sizeof (daemon_addr));

            if (cc != sizeof (CTL_MSG)) {
                if (errno == EINTR) {
            /* we are returning from an interupt */
                    continue;
                } else {
                    p_error(
                gettext("Error on write to talk daemon"));
                }
            }

            read_mask = ctl_mask;

            while ((nready = select(32, (fd_set *)&read_mask,
                0, 0, &wait)) < 0) {
            if (errno == EINTR) {
            /* we are returning from an interupt */
                continue;
            } else {
                p_error(
            gettext("Error on waiting for response from daemon"));
            }
        }
    } while (nready == 0);

    /*
     * keep reading while there are queued messages
     * (this is not necessary, it just saves extra
     * request/acknowledgements being sent)
     */

    do {

        junk_size = (socklen_t)sizeof (junk);
        cc = recvfrom(ctl_sockt, (char *)response,
            sizeof (CTL_RESPONSE), 0, &junk, &junk_size);
        if (cc < 0) {
            if (errno == EINTR) {
                continue;
            }
            p_error(gettext("Error on read from talk daemon"));
        }

        read_mask = ctl_mask;

        /* an immediate poll */

        timerclear(&wait);
        nready = select(32, (fd_set *)&read_mask, 0, 0, &wait);

    } while (nready > 0 && response->type != type);

    } while (response->type != type);
}