root/mbstring/libmbfl/filters/mbfilter_cp850.c

DEFINITIONS

1. mbfl_filt_conv_cp850_wchar
2. mbfl_filt_conv_wchar_cp850
3. mbfl_filt_ident_cp850

/*
 * "streamable kanji code filter and converter"
 * Copyright (c) 1998-2002 HappySize, Inc. All rights reserved.
 *
 * LICENSE NOTICES
 *
 * This file is part of "streamable kanji code filter and converter",
 * which is distributed under the terms of GNU Lesser General Public 
 * License (version 2) as published by the Free Software Foundation.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with "streamable kanji code filter and converter";
 * if not, write to the Free Software Foundation, Inc., 59 Temple Place,
 * Suite 330, Boston, MA  02111-1307  USA
 *
 * The author of this part: Den V. Tsopa <tdv@edisoft.ru>
 * Adaption for CP850: D. Giffeler <dg@artegic.de>
 *
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "mbfilter.h"
#include "mbfilter_cp850.h"
#include "unicode_table_cp850.h"

static int mbfl_filt_ident_cp850(int c, mbfl_identify_filter *filter);

static const char *mbfl_encoding_cp850_aliases[] = {"CP850", "CP-850", "IBM850", "IBM-850", NULL};

const mbfl_encoding mbfl_encoding_cp850 = {
        mbfl_no_encoding_cp850,
        "CP850",
        "CP850",
        (const char *(*)[])&mbfl_encoding_cp850_aliases,
        NULL,
        MBFL_ENCTYPE_SBCS
};

const struct mbfl_identify_vtbl vtbl_identify_cp850 = {
        mbfl_no_encoding_cp850,
        mbfl_filt_ident_common_ctor,
        mbfl_filt_ident_common_dtor,
        mbfl_filt_ident_cp850
};

const struct mbfl_convert_vtbl vtbl_wchar_cp850 = {
        mbfl_no_encoding_wchar,
        mbfl_no_encoding_cp850,
        mbfl_filt_conv_common_ctor,
        mbfl_filt_conv_common_dtor,
        mbfl_filt_conv_wchar_cp850,
        mbfl_filt_conv_common_flush
};

const struct mbfl_convert_vtbl vtbl_cp850_wchar = {
        mbfl_no_encoding_cp850,
        mbfl_no_encoding_wchar,
        mbfl_filt_conv_common_ctor,
        mbfl_filt_conv_common_dtor,
        mbfl_filt_conv_cp850_wchar,
        mbfl_filt_conv_common_flush
};

#define CK(statement)   do { if ((statement) < 0) return (-1); } while (0)

/*
 * cp850 => wchar
 */
int
mbfl_filt_conv_cp850_wchar(int c, mbfl_convert_filter *filter)
{
        int s;

        if (c >= 0 && c < cp850_ucs_table_min) {
                s = c;
        } else if (c >= cp850_ucs_table_min && c < 0x100) {
                s = cp850_ucs_table[c - cp850_ucs_table_min];
                if (s <= 0) {
                        s = c;
                        s &= MBFL_WCSPLANE_MASK;
                        s |= MBFL_WCSPLANE_CP850;
                }
        } else {
                s = c;
                s &= MBFL_WCSGROUP_MASK;
                s |= MBFL_WCSGROUP_THROUGH;
        }

        CK((*filter->output_function)(s, filter->data));

        return c;
}

/*
 * wchar => cp850
 */
int
mbfl_filt_conv_wchar_cp850(int c, mbfl_convert_filter *filter)
{
        int s, n;

        if (c < 0x80) {
                s = c;
        } else {
                s = -1;
                n = cp850_ucs_table_len-1;
                while (n >= 0) {
                        if (c == cp850_ucs_table[n]) {
                                s = cp850_ucs_table_min + n;
                                break;
                        }
                        n--;
                }
                if (s <= 0 && (c & ~MBFL_WCSPLANE_MASK) == MBFL_WCSPLANE_CP850) {
                        s = c & MBFL_WCSPLANE_MASK;
                }
        }

        if (s >= 0) {
                CK((*filter->output_function)(s, filter->data));
        } else {
                if (filter->illegal_mode != MBFL_OUTPUTFILTER_ILLEGAL_MODE_NONE) {
                        CK(mbfl_filt_conv_illegal_output(c, filter));
                }
        }

        return c;
}

static int mbfl_filt_ident_cp850(int c, mbfl_identify_filter *filter)
{
        if (c >= 0x80 && c < 0xff)
                filter->flag = 0;
        else
                filter->flag = 1; /* not it */
        return c;       
}