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

/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include "mt.h"
#include <errno.h>
#include <unistd.h>
#include <stropts.h>
#include <sys/stream.h>
#define _SUN_TPI_VERSION 2
#include <sys/tihdr.h>
#include <sys/timod.h>
#include <xti.h>
#include <signal.h>
#include <syslog.h>
#include "tx.h"

int
_tx_snddis(int fd, const struct t_call *call, int api_semantics)
{
        struct T_discon_req dreq;
        struct strbuf ctlbuf;
        struct strbuf databuf;
        struct _ti_user *tiptr;
        int sv_errno;
        int retval;

        if ((tiptr = _t_checkfd(fd, 0, api_semantics)) == NULL)
                return (-1);
        sig_mutex_lock(&tiptr->ti_lock);

        if (tiptr->ti_servtype == T_CLTS) {
                t_errno = TNOTSUPPORT;
                sig_mutex_unlock(&tiptr->ti_lock);
                return (-1);
        }

        if (_T_IS_XTI(api_semantics)) {
                /*
                 * User level state verification only done for XTI
                 * because doing for TLI may break existing applications
                 * Note: This is documented in TLI man page but never
                 * done.
                 */
                if (!(tiptr->ti_state == T_DATAXFER ||
                    tiptr->ti_state == T_OUTCON ||
                    tiptr->ti_state == T_OUTREL ||
                    tiptr->ti_state == T_INREL ||
                    (tiptr->ti_state == T_INCON && tiptr->ti_ocnt > 0))) {
                        t_errno = TOUTSTATE;
                        sig_mutex_unlock(&tiptr->ti_lock);
                        return (-1);
                }

                /*
                 * Following check only done for XTI as it may be a risk
                 * to existing buggy TLI applications.
                 */
        }

        if (call != NULL && call->udata.len) {
                if ((tiptr->ti_ddatasize == T_INVALID /* -2 */) ||
                    ((tiptr->ti_ddatasize != T_INFINITE /* -1*/) &&
                        (call->udata.len >
                            (uint32_t)tiptr->ti_ddatasize))) {
                        /*
                         * user data not valid with disconnect or it
                         * exceeds the limits specified by the
                         * transport provider
                         */
                        t_errno = TBADDATA;
                        sig_mutex_unlock(&tiptr->ti_lock);
                        return (-1);
                }
        }

        /*
         * If disconnect is done on a listener, the 'call' parameter
         * must be non-null
         */
        if ((tiptr->ti_state == T_INCON) &&
            (call == NULL)) {
                t_errno = TBADSEQ;
                sig_mutex_unlock(&tiptr->ti_lock);
                return (-1);
        }

        /*
         * look at look buffer to see if there is a discon there
         */

        if (_t_look_locked(fd, tiptr, 0, api_semantics) == T_DISCONNECT) {
                t_errno = TLOOK;
                sig_mutex_unlock(&tiptr->ti_lock);
                return (-1);
        }

        if ((tiptr->ti_lookcnt > 0) && (call == 0))
                _t_flush_lookevents(tiptr); /* flush but not on listener */

        do {
                retval = ioctl(fd, I_FLUSH, FLUSHW);
        } while (retval < 0 && errno == EINTR);
        if (retval < 0) {
                sv_errno = errno;
                t_errno = TSYSERR;
                sig_mutex_unlock(&tiptr->ti_lock);
                errno = sv_errno;
                return (-1);
        }

        ctlbuf.len = (int)sizeof (struct T_discon_req);
        ctlbuf.maxlen = (int)sizeof (struct T_discon_req);
        ctlbuf.buf = (char *)&dreq;

        dreq.PRIM_type = T_DISCON_REQ;
        dreq.SEQ_number = (call? call->sequence: -1);

        databuf.maxlen = (call? call->udata.len: 0);
        databuf.len = (call? call->udata.len: 0);
        databuf.buf = (call? call->udata.buf: NULL);

        /*
         * Calls to send data (write or putmsg) can potentially
         * block, for MT case, we drop the lock and enable signals here
         * and acquire it back
         */
        sig_mutex_unlock(&tiptr->ti_lock);
        if (putmsg(fd, &ctlbuf, (databuf.len? &databuf: NULL), 0) < 0) {
                t_errno = TSYSERR;
                return (-1);
        }
        sig_mutex_lock(&tiptr->ti_lock);

        if (_t_is_ok(fd, tiptr, T_DISCON_REQ) < 0) {
                sv_errno = errno;
                sig_mutex_unlock(&tiptr->ti_lock);
                errno = sv_errno;
                return (-1);
        }

        tiptr->ti_flags &= ~(MORE|EXPEDITED);

        if (tiptr->ti_ocnt <= 1) {
                if (tiptr->ti_state == T_INCON) {
                        tiptr->ti_ocnt--;
                        tiptr->ti_flags &= ~TX_TQFULL_NOTIFIED;
                }
                _T_TX_NEXTSTATE(T_SNDDIS1, tiptr,
                                "t_snddis: invalid state event T_SNDDIS1");
        } else {
                if (tiptr->ti_state == T_INCON) {
                        tiptr->ti_ocnt--;
                        tiptr->ti_flags &= ~TX_TQFULL_NOTIFIED;
                }
                _T_TX_NEXTSTATE(T_SNDDIS2, tiptr,
                                "t_snddis: invalid state event T_SNDDIS2");
        }

        sig_mutex_unlock(&tiptr->ti_lock);
        return (0);
}