/*-

 * Copyright (c)2002 Citrus Project,

 * 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.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.

 */

/*-

 * Copyright (c) 1993

 *  The Regents of the University of California.  All rights reserved.

 *

 * This code is derived from software contributed to Berkeley by

 * Paul Borman at Krystal Technologies.

 *

 * 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 "dcmtk/config/osconfig.h"

#include "citrus_euc.h"

#include <sys/types.h>

#include <errno.h>

#include <limits.h>

#include <stddef.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <wchar.h>

#include "citrus_bcs.h"

#include "citrus_types.h"

#include "citrus_module.h"

#include "citrus_stdenc.h"

/* ----------------------------------------------------------------------

 * private stuffs used by templates

 */

typedef struct {

    int  chlen;

    char     ch[3];

} _EUCState;

typedef struct {

    _citrus_wc_t      bits[4];

    _citrus_wc_t      mask;

    unsigned     count[4];

    unsigned     mb_cur_max;

} _EUCEncodingInfo;

#define _SS2    0x008e

#define _SS3    0x008f

#define _CEI_TO_EI(_cei_)       (&(_cei_)->ei)

#define _CEI_TO_STATE(_cei_, _func_)    (_cei_)->states.s_##_func_

#define _FUNCNAME(m)            _citrus_EUC_##m

#define _ENCODING_INFO          _EUCEncodingInfo

#define _ENCODING_STATE         _EUCState

#define _ENCODING_MB_CUR_MAX(_ei_)  (_ei_)->mb_cur_max

#define _ENCODING_IS_STATE_DEPENDENT    0

#define _STATE_NEEDS_EXPLICIT_INIT(_ps_)    0

static __inline int

_citrus_EUC_cs(unsigned int c)

{

    c &= 0xff;

    return ((c & 0x80) ? c == _SS3 ? 3 : c == _SS2 ? 2 : 1 : 0);

}

/* suppress MSVC 'assignment within conditional expression' warning  */

#ifdef _MSC_VER

#pragma warning(push)

#pragma warning(disable: 4706)

#endif

static __inline int

_citrus_EUC_parse_variable(_EUCEncodingInfo *ei, const void *var,

    size_t lenvar )

{

    char *e;

    const char *v;

    int x;

    (void) lenvar;

    /* parse variable string */

    if (!var)

        return (EFTYPE);

    v = (const char *)var;

    while (*v == ' ' || *v == '\t')

        ++v;

    ei->mb_cur_max = 1;

    for (x = 0; x < 4; ++x) {

        ei->count[x] = (int)_citrus_bcs_strtol(v, (char **)&e, 0);

        if (v == e || !(v = e) || ei->count[x] < 1 || ei->count[x] > 4) {

            return (EFTYPE);

        }

        if (ei->mb_cur_max < ei->count[x])

            ei->mb_cur_max = ei->count[x];

        while (*v == ' ' || *v == '\t')

            ++v;

        ei->bits[x] = (int)_citrus_bcs_strtol(v, (char **)&e, 0);

        if (v == e || !(v = e)) {

            return (EFTYPE);

        }

        while (*v == ' ' || *v == '\t')

            ++v;

    }

    ei->mask = (int)_citrus_bcs_strtol(v, (char **)&e, 0);

    if (v == e || !(v = e)) {

        return (EFTYPE);

    }

    return (0);

}

#ifdef _MSC_VER

#pragma warning(pop)

#endif

static __inline void

/*ARGSUSED*/

_citrus_EUC_init_state(_EUCEncodingInfo *ei , _EUCState *s)

{

    (void) ei;

    memset(s, 0, sizeof(*s));

}

static int

_citrus_EUC_mbrtowc_priv(_EUCEncodingInfo *ei, _citrus_wc_t *pwc, char **s,

    size_t n, _EUCState *psenc, size_t *nresult)

{

    _citrus_wc_t wchar;

    int c, chlenbak, cs, len;

    char *s0, *s1 = NULL;

    s0 = *s;

    if (s0 == NULL) {

        _citrus_EUC_init_state(ei, psenc);

        *nresult = 0; /* state independent */

        return (0);

    }

    chlenbak = psenc->chlen;

    /* make sure we have the first byte in the buffer */

    switch (psenc->chlen) {

    case 0:

        if (n < 1)

            goto restart;

        psenc->ch[0] = *s0++;

        psenc->chlen = 1;

        n--;

        break;

    case 1:

    case 2:

        break;

    default:

        /* illgeal state */

        goto encoding_error;

    }

    c = ei->count[cs = _citrus_EUC_cs(psenc->ch[0] & 0xff)];

    if (c == 0)

        goto encoding_error;

    while (psenc->chlen < c) {

        if (n < 1)

            goto restart;

        psenc->ch[psenc->chlen] = *s0++;

        psenc->chlen++;

        n--;

    }

    *s = s0;

    switch (cs) {

    case 3:

    case 2:

        /* skip SS2/SS3 */

        len = c - 1;

        s1 = &psenc->ch[1];

        break;

    case 1:

    case 0:

        len = c;

        s1 = &psenc->ch[0];

        break;

    default:

        goto encoding_error;

    }

    wchar = 0;

    while (len-- > 0)

        wchar = (wchar << 8) | (*s1++ & 0xff);

    wchar = (wchar & ~ei->mask) | ei->bits[cs];

    psenc->chlen = 0;

    if (pwc)

        *pwc = wchar;

    *nresult = wchar ? (size_t)(c - chlenbak) : 0;

    return (0);

encoding_error:

    psenc->chlen = 0;

    *nresult = (size_t)-1;

    return (EILSEQ);

restart:

    *nresult = (size_t)-2;

    *s = s0;

    return (0);

}

static int

_citrus_EUC_wcrtomb_priv(_EUCEncodingInfo *ei, char *s, size_t n, _citrus_wc_t wc,

    _EUCState *psenc , size_t *nresult)

{

    _citrus_wc_t m, nm;

    unsigned int cs;

    int ret;

    int i;

    (void) psenc;

    m = wc & ei->mask;

    nm = wc & ~m;

    for (cs = 0; cs < sizeof(ei->count) / sizeof(ei->count[0]); cs++)

        if (m == ei->bits[cs])

            break;

    /* fallback case - not sure if it is necessary */

    if (cs == sizeof(ei->count) / sizeof(ei->count[0]))

        cs = 1;

    i = ei->count[cs];

    if (n < (unsigned)i) {

        ret = E2BIG;

        goto err;

    }

    m = (cs) ? 0x80 : 0x00;

    switch (cs) {

    case 2:

        *s++ = _SS2;

        i--;

        break;

    case 3:

        *s++ = _SS3;

        i--;

        break;

    }

    while (i-- > 0)

        *s++ = (char)(((nm >> (i << 3)) & 0xff) | m);

    *nresult = (size_t)ei->count[cs];

    return (0);

err:

    *nresult = (size_t)-1;

    return (ret);

}

static __inline int

/*ARGSUSED*/

_citrus_EUC_stdenc_wctocs(_EUCEncodingInfo * ei,

    _citrus_csid_t * csid, _citrus_index_t * idx, _citrus_wc_t wc)

{

    _citrus_wc_t m, nm;

    m = wc & ei->mask;

    nm = wc & ~m;

    *csid = (_citrus_csid_t)m;

    *idx  = (_citrus_index_t)nm;

    return (0);

}

static __inline int

/*ARGSUSED*/

_citrus_EUC_stdenc_cstowc(_EUCEncodingInfo * ei,

    _citrus_wc_t * wc, _citrus_csid_t csid, _citrus_index_t idx)

{

    if ((csid & ~ei->mask) != 0 || (idx & ei->mask) != 0)

        return (EINVAL);

    *wc = (_citrus_wc_t)csid | (_citrus_wc_t)idx;

    return (0);

}

static __inline int

/*ARGSUSED*/

_citrus_EUC_stdenc_get_state_desc_generic(_EUCEncodingInfo * ei ,

    _EUCState * psenc, int * rstate)

{

    (void) ei;

    *rstate = (psenc->chlen == 0) ? _CITRUS_STDENC_SDGEN_INITIAL :

        _CITRUS_STDENC_SDGEN_INCOMPLETE_CHAR;

    return (0);

}

static int

/*ARGSUSED*/

_citrus_EUC_encoding_module_init(_EUCEncodingInfo * ei,

    const void * var, size_t lenvar)

{

    return (_citrus_EUC_parse_variable(ei, var, lenvar));

}

static void

/*ARGSUSED*/

_citrus_EUC_encoding_module_uninit(_EUCEncodingInfo * ei )

{

    (void) ei;

}

/* ----------------------------------------------------------------------

 * public interface for stdenc

 */

_CITRUS_STDENC_DECLS(EUC);

_CITRUS_STDENC_DEF_OPS(EUC);

#include "citrus_stdenc_template.h"