/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at 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 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 1994-2003 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <euc.h>
#define JFP_ICONV_STATELESS
#include "japanese.h"

void *
_icv_open(void)
{
        return (_icv_open_stateless());
}

void
_icv_close(void *cd)
{
        _icv_close_stateless(cd);
        return;
}

size_t
_icv_iconv(void *cd, char **inbuf, size_t *inbytesleft,
                                char **outbuf, size_t *outbytesleft)
{
        int stat;
        unsigned char *ip, ic;
        char *op;
        size_t ileft, oleft;
        size_t retval;

        stat = ST_INIT;

        /*
         * If inbuf and/or *inbuf are NULL, reset conversion descriptor
         * and put escape sequence if needed.
         */
        if ((inbuf == NULL) || (*inbuf == NULL)) {
                /* nothing to do here for this module */
                return ((size_t)0);
        }

        ip = (unsigned char *)*inbuf;
        op = *outbuf;
        ileft = *inbytesleft;
        oleft = *outbytesleft;

        /*
         * Main loop; basically 1 loop per 1 input byte
         */

        while ((int)ileft > 0) {
                GET(ic);
                if (stat == ST_INCS1) {
                        PUT(((ic & CMASK) - 0x20));
                        stat = ST_INIT;
                        continue;
                } else if (stat == ST_INCS3) {
                        PUT(((ic & CMASK) - 0x20));
                        GET(ic);
                        PUT(((ic & CMASK) - 0x20));
                        stat = ST_INIT;
                        continue;
                }
                if (ISASC((int)ic)) { /* ASCII */
                        errno = EILSEQ;
                        retval = (size_t)ERR_RETURN;
                        goto ret;
                } else if (ISCS1(ic)) { /* CS_1 starts */
                        if ((int)ileft > 0) {
                                if (ISCS1(ic) && ISCS1(*ip)) {
                                        if (oleft < JISW1) {
                                                UNGET();
                                                errno = E2BIG;
                                                retval = (size_t)ERR_RETURN;
                                                goto ret;
                                        }
                                        stat = ST_INCS1;
                                        PUT(((ic & CMASK) - 0x20));
                                        continue;
                                } else {
                                        errno = EILSEQ;
                                        retval = (size_t)ERR_RETURN;
                                        goto ret;
                                }
                        } else {                /* input fragment of Kanji */
                                UNGET();
                                errno = EINVAL;
                                retval = (size_t)ERR_RETURN;
                                goto ret;
                        }
                } else if (ic == SS2) { /* Kana starts */
                        errno = EILSEQ;
                        retval = (size_t)ERR_RETURN;
                        goto ret;
                } else if (ic == SS3) { /* JISX0212 starts */
                        if (ileft >= EUCW3) {
                                if (ISCS3(*ip) && ISCS3(*(ip + 1))) {
                                        if (oleft < JISW3) {
                                                UNGET();
                                                errno = E2BIG;
                                                retval = (size_t)ERR_RETURN;
                                                goto ret;
                                        }
                                        stat = ST_INCS3;
                                        continue;
                                } else {
                                        errno = EILSEQ;
                                        retval = (size_t)ERR_RETURN;
                                        goto ret;
                                }
                        } else {        /* input fragment of JISX0212 */
                                UNGET();
                                errno = EINVAL;
                                retval = (size_t)ERR_RETURN;
                                goto ret;
                        }
                } else {
                        UNGET();
                        errno = EILSEQ;
                        retval = (size_t)ERR_RETURN;
                        goto ret;
                }
        }
        retval = ileft;
ret:
        *inbuf = (char *)ip;
        *inbytesleft = ileft;
ret2:
        *outbuf = op;
        *outbytesleft = oleft;

        return (retval);
}