/*
 * 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 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include "mt.h"
#include <errno.h>
#include <stdlib.h>
#include <string.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 <syslog.h>
#include "tx.h"

int
_tx_listen(int fd, struct t_call *call, int api_semantics)
{
        struct strbuf ctlbuf;
        struct strbuf databuf;
        int retval;
        union T_primitives *pptr;
        struct _ti_user *tiptr;
        int sv_errno;
        int didalloc, didralloc;
        int flg = 0;

        if ((tiptr = _t_checkfd(fd, 0, api_semantics)) == NULL)
                return (-1);

        sig_mutex_lock(&tiptr->ti_lock);

        if (tiptr->ti_servtype == T_CLTS) {
                sv_errno = errno;
                t_errno = TNOTSUPPORT;
                sig_mutex_unlock(&tiptr->ti_lock);
                errno = sv_errno;
                return (-1);
        }
        if (_T_IS_XTI(api_semantics)) {
                /*
                 * User level state verification only done for XTI
                 * because doing for TLI may break existing applications
                 */
                if (!(tiptr->ti_state == T_IDLE ||
                    tiptr->ti_state == T_INCON)) {
                        t_errno = TOUTSTATE;
                        sig_mutex_unlock(&tiptr->ti_lock);
                        return (-1);
                }

                if (tiptr->ti_qlen == 0) {
                        t_errno = TBADQLEN;
                        sig_mutex_unlock(&tiptr->ti_lock);
                        return (-1);
                }

                if (tiptr->ti_ocnt == tiptr->ti_qlen) {
                        if (!(tiptr->ti_flags & TX_TQFULL_NOTIFIED)) {
                                tiptr->ti_flags |= TX_TQFULL_NOTIFIED;
                                t_errno = TQFULL;
                                sig_mutex_unlock(&tiptr->ti_lock);
                                return (-1);
                        }
                }

        }

        /*
         * check if something in look buffer
         */
        if (tiptr->ti_lookcnt > 0) {
                t_errno = TLOOK;
                sig_mutex_unlock(&tiptr->ti_lock);
                return (-1);
        }

        /*
         * Acquire ctlbuf for use in sending/receiving control part
         * of the message.
         */
        if (_t_acquire_ctlbuf(tiptr, &ctlbuf, &didalloc) < 0) {
                sv_errno = errno;
                sig_mutex_unlock(&tiptr->ti_lock);
                errno = sv_errno;
                return (-1);
        }
        /*
         * Acquire databuf for use in sending/receiving data part
         */
        if (_t_acquire_databuf(tiptr, &databuf, &didralloc) < 0) {
                int sv_errno = errno;

                if (didalloc)
                        free(ctlbuf.buf);
                else
                        tiptr->ti_ctlbuf = ctlbuf.buf;
                sig_mutex_unlock(&tiptr->ti_lock);
                errno = sv_errno;
                return (-1);
        }

        /*
         * This is a call that may block indefinitely so we drop the
         * lock and allow signals in MT case here and reacquire it.
         * Error case should roll back state changes done above
         * (happens to be no state change here)
         */
        sig_mutex_unlock(&tiptr->ti_lock);
        if ((retval = getmsg(fd, &ctlbuf, &databuf, &flg)) < 0) {
                if (errno == EAGAIN)
                        t_errno = TNODATA;
                else
                        t_errno = TSYSERR;
                sv_errno = errno;
                sig_mutex_lock(&tiptr->ti_lock);
                errno = sv_errno;
                goto err_out;
        }
        sig_mutex_lock(&tiptr->ti_lock);

        if (databuf.len == -1) databuf.len = 0;

        /*
         * did I get entire message?
         */
        if (retval > 0) {
                t_errno = TSYSERR;
                errno = EIO;
                goto err_out;
        }

        /*
         * is ctl part large enough to determine type
         */
        if (ctlbuf.len < (int)sizeof (t_scalar_t)) {
                t_errno = TSYSERR;
                errno = EPROTO;
                goto err_out;
        }

        /* LINTED pointer cast */
        pptr = (union T_primitives *)ctlbuf.buf;

        switch (pptr->type) {

        case T_CONN_IND:
                if ((ctlbuf.len < (int)sizeof (struct T_conn_ind)) ||
                    (ctlbuf.len < (int)(pptr->conn_ind.OPT_length
                    + pptr->conn_ind.OPT_offset))) {
                        t_errno = TSYSERR;
                        errno = EPROTO;
                        goto err_out;
                }
                /*
                 * Change state and increment outstanding connection
                 * indication count and instantiate "sequence" return
                 * parameter.
                 * Note: It is correct semantics accoring to spec to
                 * do this despite possibility of TBUFOVFLW error later.
                 * The spec treats TBUFOVFLW error in general as a special case
                 * which can be ignored by applications that do not
                 * really need the stuff returned in 'netbuf' structures.
                 */
                _T_TX_NEXTSTATE(T_LISTN, tiptr,
                                "t_listen:invalid state event T_LISTN");
                tiptr->ti_ocnt++;
                call->sequence = pptr->conn_ind.SEQ_number;

                if (_T_IS_TLI(api_semantics) || call->addr.maxlen > 0) {
                        if (TLEN_GT_NLEN(pptr->conn_ind.SRC_length,
                            call->addr.maxlen)) {
                                t_errno = TBUFOVFLW;
                                goto err_out;
                        }
                        (void) memcpy(call->addr.buf, ctlbuf.buf +
                            (size_t)pptr->conn_ind.SRC_offset,
                        (unsigned int)pptr->conn_ind.SRC_length);
                        call->addr.len = pptr->conn_ind.SRC_length;
                }
                if (_T_IS_TLI(api_semantics) || call->opt.maxlen > 0) {
                        if (TLEN_GT_NLEN(pptr->conn_ind.OPT_length,
                            call->opt.maxlen)) {
                                t_errno = TBUFOVFLW;
                                goto err_out;
                        }
                        (void) memcpy(call->opt.buf, ctlbuf.buf +
                            pptr->conn_ind.OPT_offset,
                            (size_t)pptr->conn_ind.OPT_length);
                        call->opt.len = pptr->conn_ind.OPT_length;
                }
                if (_T_IS_TLI(api_semantics) || call->udata.maxlen > 0) {
                        if (databuf.len > (int)call->udata.maxlen) {
                                t_errno = TBUFOVFLW;
                                goto err_out;
                        }
                        (void) memcpy(call->udata.buf, databuf.buf,
                            (size_t)databuf.len);
                        call->udata.len = databuf.len;
                }

                if (didalloc)
                        free(ctlbuf.buf);
                else
                        tiptr->ti_ctlbuf = ctlbuf.buf;
                if (didralloc)
                        free(databuf.buf);
                else
                        tiptr->ti_rcvbuf = databuf.buf;
                sig_mutex_unlock(&tiptr->ti_lock);
                return (0);

        case T_DISCON_IND:
                /*
                 * Append to the events in the "look buffer"
                 * list of events. This routine may defer signals.
                 */
                if (_t_register_lookevent(tiptr, databuf.buf,
                                        databuf.len, ctlbuf.buf,
                                        ctlbuf.len) < 0) {
                        t_errno = TSYSERR;
                        errno = ENOMEM;
                        goto err_out;
                }
                t_errno = TLOOK;
                goto err_out;

        default:
                break;
        }

        t_errno = TSYSERR;
        errno = EPROTO;
err_out:
        sv_errno = errno;

        if (didalloc)
                free(ctlbuf.buf);
        else
                tiptr->ti_ctlbuf = ctlbuf.buf;
        if (didralloc)
                free(databuf.buf);
        else
                tiptr->ti_rcvbuf = databuf.buf;
        sig_mutex_unlock(&tiptr->ti_lock);
        errno = sv_errno;
        return (-1);
}