root/mbstring/libmbfl/filters/mbfilter_utf7.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. mbfl_filt_conv_utf7_wchar
  2. mbfl_filt_conv_wchar_utf7
  3. mbfl_filt_conv_wchar_utf7_flush
  4. mbfl_filt_ident_utf7

/*
 * "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 file:
 *
 */
/*
 * The source code included in this files was separated from mbfilter.c
 * by moriyoshi koizumi <moriyoshi@php.net> on 4 dec 2002.
 * 
 */

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

#include "mbfilter.h"
#include "mbfilter_utf7.h"

static int mbfl_filt_ident_utf7(int c, mbfl_identify_filter *filter);

static const unsigned char mbfl_base64_table[] = {
 /* 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', */
   0x41,0x42,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x4b,0x4c,0x4d,
 /* 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', */
   0x4e,0x4f,0x50,0x51,0x52,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5a,
 /* 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', */
   0x61,0x62,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x6b,0x6c,0x6d,
 /* 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', */
   0x6e,0x6f,0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,
 /* '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/', '\0' */
   0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39,0x2b,0x2f,0x00
};

static const char *mbfl_encoding_utf7_aliases[] = {"utf7", NULL};

const mbfl_encoding mbfl_encoding_utf7 = {
        mbfl_no_encoding_utf7,
        "UTF-7",
        "UTF-7",
        (const char *(*)[])&mbfl_encoding_utf7_aliases,
        NULL,
        MBFL_ENCTYPE_MBCS | MBFL_ENCTYPE_SHFTCODE | MBFL_ENCTYPE_GL_UNSAFE
};

const struct mbfl_identify_vtbl vtbl_identify_utf7 = {
        mbfl_no_encoding_utf7,
        mbfl_filt_ident_common_ctor,
        mbfl_filt_ident_common_dtor,
        mbfl_filt_ident_utf7
};

const struct mbfl_convert_vtbl vtbl_utf7_wchar = {
        mbfl_no_encoding_utf7,
        mbfl_no_encoding_wchar,
        mbfl_filt_conv_common_ctor,
        mbfl_filt_conv_common_dtor,
        mbfl_filt_conv_utf7_wchar,
        mbfl_filt_conv_common_flush
};

const struct mbfl_convert_vtbl vtbl_wchar_utf7 = {
        mbfl_no_encoding_wchar,
        mbfl_no_encoding_utf7,
        mbfl_filt_conv_common_ctor,
        mbfl_filt_conv_common_dtor,
        mbfl_filt_conv_wchar_utf7,
        mbfl_filt_conv_wchar_utf7_flush
};


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

/*
 * UTF-7 => wchar
 */
int mbfl_filt_conv_utf7_wchar(int c, mbfl_convert_filter *filter)
{
        int s, n;

        n = -1;
        if (filter->status != 0) {              /* Modified Base64 */
                if (c >= 0x41 && c <= 0x5a) {           /* A - Z */
                        n = c - 65;
                } else if (c >= 0x61 && c <= 0x7a) {    /* a - z */
                        n = c - 71;
                } else if (c >= 0x30 && c <= 0x39) {    /* 0 - 9 */
                        n = c + 4;
                } else if (c == 0x2b) {                 /* '+' */
                        n = 62;
                } else if (c == 0x2f) {                 /* '/' */
                        n = 63;
                }
                if (n < 0 || n > 63) {
                        if (c == 0x2d) {
                                if (filter->status == 1) {              /* "+-" -> "+" */
                                        CK((*filter->output_function)(0x2b, filter->data));
                                }
                        } else if (c >= 0 && c < 0x80) {        /* ASCII exclude '-' */
                                CK((*filter->output_function)(c, filter->data));
                        } else {                /* illegal character */
                                s = c & MBFL_WCSGROUP_MASK;
                                s |= MBFL_WCSGROUP_THROUGH;
                                CK((*filter->output_function)(s, filter->data));
                        }
                        filter->cache = 0;
                        filter->status = 0;
                        return c;
                }
        }

        switch (filter->status) {
        /* directly encoded characters */
        case 0:
                if (c == 0x2b) {        /* '+'  shift character */
                        filter->status = 1;
                } else if (c >= 0 && c < 0x80) {        /* ASCII */
                        CK((*filter->output_function)(c, filter->data));
                } else {                /* illegal character */
                        s = c & MBFL_WCSGROUP_MASK;
                        s |= MBFL_WCSGROUP_THROUGH;
                        CK((*filter->output_function)(s, filter->data));
                }
                break;

        /* decode Modified Base64 */
        case 1:
        case 2:
                filter->cache |= n << 10;
                filter->status = 3;
                break;
        case 3:
                filter->cache |= n << 4;
                filter->status = 4;
                break;
        case 4:
                s = ((n >> 2) & 0xf) | (filter->cache & 0xffff);
                n = (n & 0x3) << 14;
                filter->status = 5;
                if (s >= 0xd800 && s < 0xdc00) {
                        s = (((s & 0x3ff) << 16) + 0x400000) | n;
                        filter->cache = s;
                } else if (s >= 0xdc00 && s < 0xe000) {
                        s &= 0x3ff;
                        s |= (filter->cache & 0xfff0000) >> 6;
                        filter->cache = n;
                        if (s >= MBFL_WCSPLANE_SUPMIN && s < MBFL_WCSPLANE_SUPMAX) {
                                CK((*filter->output_function)(s, filter->data));
                        } else {                /* illegal character */
                                s &= MBFL_WCSGROUP_MASK;
                                s |= MBFL_WCSGROUP_THROUGH;
                                CK((*filter->output_function)(s, filter->data));
                        }
                } else {
                        filter->cache = n;
                        CK((*filter->output_function)(s, filter->data));
                }
                break;

        case 5:
                filter->cache |= n << 8;
                filter->status = 6;
                break;
        case 6:
                filter->cache |= n << 2;
                filter->status = 7;
                break;
        case 7:
                s = ((n >> 4) & 0x3) | (filter->cache & 0xffff);
                n = (n & 0xf) << 12;
                filter->status = 8;
                if (s >= 0xd800 && s < 0xdc00) {
                        s = (((s & 0x3ff) << 16) + 0x400000) | n;
                        filter->cache = s;
                } else if (s >= 0xdc00 && s < 0xe000) {
                        s &= 0x3ff;
                        s |= (filter->cache & 0xfff0000) >> 6;
                        filter->cache = n;
                        if (s >= MBFL_WCSPLANE_SUPMIN && s < MBFL_WCSPLANE_SUPMAX) {
                                CK((*filter->output_function)(s, filter->data));
                        } else {                /* illegal character */
                                s &= MBFL_WCSGROUP_MASK;
                                s |= MBFL_WCSGROUP_THROUGH;
                                CK((*filter->output_function)(s, filter->data));
                        }
                } else {
                        filter->cache = n;
                        CK((*filter->output_function)(s, filter->data));
                }
                break;

        case 8:
                filter->cache |= n << 6;
                filter->status = 9;
                break;
        case 9:
                s = n | (filter->cache & 0xffff);
                filter->status = 2;
                if (s >= 0xd800 && s < 0xdc00) {
                        s = (((s & 0x3ff) << 16) + 0x400000);
                        filter->cache = s;
                } else if (s >= 0xdc00 && s < 0xe000) {
                        s &= 0x3ff;
                        s |= (filter->cache & 0xfff0000) >> 6;
                        filter->cache = 0;
                        if (s >= MBFL_WCSPLANE_SUPMIN && s < MBFL_WCSPLANE_SUPMAX) {
                                CK((*filter->output_function)(s, filter->data));
                        } else {                /* illegal character */
                                s &= MBFL_WCSGROUP_MASK;
                                s |= MBFL_WCSGROUP_THROUGH;
                                CK((*filter->output_function)(s, filter->data));
                        }
                } else {
                        filter->cache = 0;
                        CK((*filter->output_function)(s, filter->data));
                }
                break;

        default:
                filter->status = 0;
                break;
        }

        return c;
}

/*
 * wchar => UTF-7
 */
int mbfl_filt_conv_wchar_utf7(int c, mbfl_convert_filter *filter)
{
        int s, n;

        n = 0;
        if (c >= 0 && c < 0x80) {       /* ASCII */
                if (c >= 0x41 && c <= 0x5a) {           /* A - Z */
                        n = 1;
                } else if (c >= 0x61 && c <= 0x7a) {    /* a - z */
                        n = 1;
                } else if (c >= 0x30 && c <= 0x39) {    /* 0 - 9 */
                        n = 1;
                } else if (c == '\0') {                 /* '\0' */
                        n = 1;
                } else if (c == 0x2f) {                 /* '/' */
                        n = 1;
                } else if (c == 0x2d) {                 /* '-' */
                        n = 1;
                } else if (c == 0x20) {                 /* SPACE */
                        n = 2;
                } else if (c == 0x09) {                 /* HTAB */
                        n = 2;
                } else if (c == 0x0d) {                 /* CR */
                        n = 2;
                } else if (c == 0x0a) {                 /* LF */
                        n = 2;
                } else if (c == 0x27) {                 /* "'" */
                        n = 2;
                } else if (c == 0x28) {                 /* '(' */
                        n = 2;
                } else if (c == 0x29) {                 /* ')' */
                        n = 2;
                } else if (c == 0x2c) {                 /* ',' */
                        n = 2;
                } else if (c == 0x2e) {                 /* '.' */
                        n = 2;
                } else if (c == 0x3a) {                 /* ':' */
                        n = 2;
                } else if (c == 0x3f) {                 /* '?' */
                        n = 2;
                }
        } else if (c >= 0 && c < MBFL_WCSPLANE_UCS2MAX) {
                ;
        } else if (c >= MBFL_WCSPLANE_SUPMIN && c < MBFL_WCSPLANE_SUPMAX) {
                s = ((c >> 10) - 0x40) | 0xd800;
                CK((*filter->filter_function)(s, filter));
                s = (c & 0x3ff) | 0xdc00;
                CK((*filter->filter_function)(s, filter));
                return c;
        } else {
                if (filter->illegal_mode != MBFL_OUTPUTFILTER_ILLEGAL_MODE_NONE) {
                        CK(mbfl_filt_conv_illegal_output(c, filter));
                }
                return c;
        }

        switch (filter->status) {
        case 0:
                if (n != 0) {   /* directly encode characters */
                        CK((*filter->output_function)(c, filter->data));
                } else {        /* Modified Base64 */
                        CK((*filter->output_function)(0x2b, filter->data));             /* '+' */
                        filter->status++;
                        filter->cache = c;
                }
                break;

        /* encode Modified Base64 */
        case 1:
                s = filter->cache;
                CK((*filter->output_function)(mbfl_base64_table[(s >> 10) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[(s >> 4) & 0x3f], filter->data));
                if (n != 0) {
                        CK((*filter->output_function)(mbfl_base64_table[(s << 2) & 0x3c], filter->data));
                        if (n == 1) {
                                CK((*filter->output_function)(0x2d, filter->data));             /* '-' */
                        }
                        CK((*filter->output_function)(c, filter->data));
                        filter->status = 0;
                } else {
                        filter->status++;
                        filter->cache = ((s & 0xf) << 16) | c;
                }
                break;

        case 2:
                s = filter->cache;
                CK((*filter->output_function)(mbfl_base64_table[(s >> 14) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[(s >> 8) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[(s >> 2) & 0x3f], filter->data));
                if (n != 0) {
                        CK((*filter->output_function)(mbfl_base64_table[(s << 4) & 0x30], filter->data));
                        if (n == 1) {
                                CK((*filter->output_function)(0x2d, filter->data));             /* '-' */
                        }
                        CK((*filter->output_function)(c, filter->data));
                        filter->status = 0;
                } else {
                        filter->status++;
                        filter->cache = ((s & 0x3) << 16) | c;
                }
                break;

        case 3:
                s = filter->cache;
                CK((*filter->output_function)(mbfl_base64_table[(s >> 12) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[(s >> 6) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[s & 0x3f], filter->data));
                if (n != 0) {
                        if (n == 1) {
                                CK((*filter->output_function)(0x2d, filter->data));             /* '-' */
                        }
                        CK((*filter->output_function)(c, filter->data));
                        filter->status = 0;
                } else {
                        filter->status = 1;
                        filter->cache = c;
                }
                break;

        default:
                filter->status = 0;
                break;
        }

        return c;

}

int mbfl_filt_conv_wchar_utf7_flush(mbfl_convert_filter *filter)
{
        int status, cache;

        status = filter->status;
        cache = filter->cache;
        filter->status = 0;
        filter->cache = 0;
        /* flush fragments */
        switch (status) {
        case 1:
                CK((*filter->output_function)(mbfl_base64_table[(cache >> 10) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[(cache >> 4) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[(cache << 2) & 0x3c], filter->data));
                CK((*filter->output_function)(0x2d, filter->data));             /* '-' */
                break;

        case 2:
                CK((*filter->output_function)(mbfl_base64_table[(cache >> 14) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[(cache >> 8) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[(cache >> 2) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[(cache << 4) & 0x30], filter->data));
                CK((*filter->output_function)(0x2d, filter->data));             /* '-' */
                break;

        case 3:
                CK((*filter->output_function)(mbfl_base64_table[(cache >> 12) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[(cache >> 6) & 0x3f], filter->data));
                CK((*filter->output_function)(mbfl_base64_table[cache & 0x3f], filter->data));
                CK((*filter->output_function)(0x2d, filter->data));             /* '-' */
                break;
        }

        if (filter->flush_function != NULL) {
                (*filter->flush_function)(filter->data);
        }

        return 0;
}

static int mbfl_filt_ident_utf7(int c, mbfl_identify_filter *filter)
{
        int n;

        switch (filter->status) {
        /* directly encoded characters */
        case 0:
                if (c == 0x2b) {        /* '+'  shift character */
                        filter->status++;
                } else if (c == 0x5c || c == 0x7e || c < 0 || c > 0x7f) {       /* illegal character */
                        filter->flag = 1;       /* bad */
                }
                break;

        /* Modified Base64 */
        case 1:
        case 2:
                n = 0;
                if (c >= 0x41 && c <= 0x5a) {           /* A - Z */
                        n = 1;
                } else if (c >= 0x61 && c <= 0x7a) {    /* a - z */
                        n = 1;
                } else if (c >= 0x30 && c <= 0x39) {    /* 0 - 9 */
                        n = 1;
                } else if (c == 0x2b) {                 /* '+' */
                        n = 1;
                } else if (c == 0x2f) {                 /* '/' */
                        n = 1;
                }
                if (n <= 0) {
                        if (filter->status == 1 && c != 0x2d) {
                                filter->flag = 1;       /* bad */
                        } else if (c < 0 || c > 0x7f) {
                                filter->flag = 1;       /* bad */
                        }
                        filter->status = 0;
                } else {
                        filter->status = 2;
                }
                break;

        default:
                filter->status = 0;
                break;
        }

        return c;
}



/* [<][>][^][v][top][bottom][index][help] */