release/src/router/libiconv/lib/big5hkscs2001.h

   1 /*
   2  * Copyright (C) 1999-2002, 2006 Free Software Foundation, Inc.
   3  * This file is part of the GNU LIBICONV Library.
   4  *
   5  * The GNU LIBICONV Library is free software; you can redistribute it
   6  * and/or modify it under the terms of the GNU Library General Public
   7  * License as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * The GNU LIBICONV Library is distributed in the hope that it will be
  11  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Library General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Library General Public
  16  * License along with the GNU LIBICONV Library; see the file COPYING.LIB.
  17  * If not, write to the Free Software Foundation, Inc., 51 Franklin Street,
  18  * Fifth Floor, Boston, MA 02110-1301, USA.
  19  */
  20
  21 /*
  22  * BIG5-HKSCS:2001
  23  */
  24
  25 /*
  26  * BIG5-HKSCS:2001 can be downloaded from
  27  *   http://www.info.gov.hk/digital21/eng/hkscs/download.html
  28  *   http://www.info.gov.hk/digital21/eng/hkscs/index.html
  29  *
  30  * It extends BIG5-HKSCS:1999 through 116 characters.
  31  *
  32  * It extends BIG5 (without the rows 0xC6..0xC7) through the ranges
  33  *
  34  *   0x{88..8D}{40..7E,A1..FE}      757 characters
  35  *   0x{8E..A0}{40..7E,A1..FE}     2898 characters
  36  *   0x{C6..C8}{40..7E,A1..FE}      359 characters
  37  *   0xF9{D6..FE}                    41 characters
  38  *   0x{FA..FE}{40..7E,A1..FE}      763 characters
  39  *
  40  * Note that some HKSCS characters are not contained in Unicode 3.2
  41  * and are therefore best represented as sequences of Unicode characters:
  42  *   0x8862  U+00CA U+0304  LATIN CAPITAL LETTER E WITH CIRCUMFLEX AND MACRON
  43  *   0x8864  U+00CA U+030C  LATIN CAPITAL LETTER E WITH CIRCUMFLEX AND CARON
  44  *   0x88A3  U+00EA U+0304  LATIN SMALL LETTER E WITH CIRCUMFLEX AND MACRON
  45  *   0x88A5  U+00EA U+030C  LATIN SMALL LETTER E WITH CIRCUMFLEX AND CARON
  46  */
  47
  48 #include "hkscs2001.h"
  49 #include "flushwc.h"
  50
  51 static int
  52 big5hkscs2001_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n)
  53 {
  54   ucs4_t last_wc = conv->istate;
  55   if (last_wc) {
  56     /* Output the buffered character. */
  57     conv->istate = 0;
  58     *pwc = last_wc;
  59     return 0; /* Don't advance the input pointer. */
  60   } else {
  61     unsigned char c = *s;
  62     /* Code set 0 (ASCII) */
  63     if (c < 0x80)
  64       return ascii_mbtowc(conv,pwc,s,n);
  65     /* Code set 1 (BIG5 extended) */
  66     if (c >= 0xa1 && c < 0xff) {
  67       if (n < 2)
  68         return RET_TOOFEW(0);
  69       {
  70         unsigned char c2 = s[1];
  71         if ((c2 >= 0x40 && c2 < 0x7f) || (c2 >= 0xa1 && c2 < 0xff)) {
  72           if (!((c == 0xc6 && c2 >= 0xa1) || c == 0xc7)) {
  73             int ret = big5_mbtowc(conv,pwc,s,2);
  74             if (ret != RET_ILSEQ)
  75               return ret;
  76           }
  77         }
  78       }
  79     }
  80     {
  81       int ret = hkscs1999_mbtowc(conv,pwc,s,n);
  82       if (ret != RET_ILSEQ)
  83         return ret;
  84     }
  85     {
  86       int ret = hkscs2001_mbtowc(conv,pwc,s,n);
  87       if (ret != RET_ILSEQ)
  88         return ret;
  89     }
  90     if (c == 0x88) {
  91       if (n < 2)
  92         return RET_TOOFEW(0);
  93       {
  94         unsigned char c2 = s[1];
  95         if (c2 == 0x62 || c2 == 0x64 || c2 == 0xa3 || c2 == 0xa5) {
  96           /* It's a composed character. */
  97           ucs4_t wc1 = ((c2 >> 3) << 2) + 0x009a; /* = 0x00ca or 0x00ea */
  98           ucs4_t wc2 = ((c2 & 6) << 2) + 0x02fc; /* = 0x0304 or 0x030c */
  99           /* We cannot output two Unicode characters at once. So,
 100              output the first character and buffer the second one. */
 101           *pwc = wc1;
 102           conv->istate = wc2;
 103           return 2;
 104         }
 105       }
 106     }
 107     return RET_ILSEQ;
 108   }
 109 }
 110
 111 #define big5hkscs2001_flushwc normal_flushwc
 112
 113 static int
 114 big5hkscs2001_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n)
 115 {
 116   int count = 0;
 117   unsigned char last = conv->ostate;
 118
 119   if (last) {
 120     /* last is = 0x66 or = 0xa7. */
 121     if (wc == 0x0304 || wc == 0x030c) {
 122       /* Output the combined character. */
 123       if (n >= 2) {
 124         r[0] = 0x88;
 125         r[1] = last + ((wc & 24) >> 2) - 4; /* = 0x62 or 0x64 or 0xa3 or 0xa5 */
 126         conv->ostate = 0;
 127         return 2;
 128       } else
 129         return RET_TOOSMALL;
 130     }
 131
 132     /* Output the buffered character. */
 133     if (n < 2)
 134       return RET_TOOSMALL;
 135     r[0] = 0x88;
 136     r[1] = last;
 137     r += 2;
 138     count = 2;
 139   }
 140
 141   /* Code set 0 (ASCII) */
 142   if (wc < 0x0080) {
 143     /* Plain ASCII character. */
 144     if (n > count) {
 145       r[0] = (unsigned char) wc;
 146       conv->ostate = 0;
 147       return count+1;
 148     } else
 149       return RET_TOOSMALL;
 150   } else {
 151     unsigned char buf[2];
 152     int ret;
 153
 154     /* Code set 1 (BIG5 extended) */
 155     ret = big5_wctomb(conv,buf,wc,2);
 156     if (ret != RET_ILUNI) {
 157       if (ret != 2) abort();
 158       if (!((buf[0] == 0xc6 && buf[1] >= 0xa1) || buf[0] == 0xc7)) {
 159         if (n >= count+2) {
 160           r[0] = buf[0];
 161           r[1] = buf[1];
 162           conv->ostate = 0;
 163           return count+2;
 164         } else
 165           return RET_TOOSMALL;
 166       }
 167     }
 168     ret = hkscs1999_wctomb(conv,buf,wc,2);
 169     if (ret != RET_ILUNI) {
 170       if (ret != 2) abort();
 171       if ((wc & ~0x0020) == 0x00ca) {
 172         /* A possible first character of a multi-character sequence. We have to
 173            buffer it. */
 174         if (!(buf[0] == 0x88 && (buf[1] == 0x66 || buf[1] == 0xa7))) abort();
 175         conv->ostate = buf[1]; /* = 0x66 or = 0xa7 */
 176         return count+0;
 177       }
 178       if (n >= count+2) {
 179         r[0] = buf[0];
 180         r[1] = buf[1];
 181         conv->ostate = 0;
 182         return count+2;
 183       } else
 184         return RET_TOOSMALL;
 185     }
 186     ret = hkscs2001_wctomb(conv,buf,wc,2);
 187     if (ret != RET_ILUNI) {
 188       if (ret != 2) abort();
 189       if (n >= count+2) {
 190         r[0] = buf[0];
 191         r[1] = buf[1];
 192         conv->ostate = 0;
 193         return count+2;
 194       } else
 195         return RET_TOOSMALL;
 196     }
 197     return RET_ILUNI;
 198   }
 199 }
 200
 201 static int
 202 big5hkscs2001_reset (conv_t conv, unsigned char *r, int n)
 203 {
 204   unsigned char last = conv->ostate;
 205
 206   if (last) {
 207     if (n < 2)
 208       return RET_TOOSMALL;
 209     r[0] = 0x88;
 210     r[1] = last;
 211     /* conv->ostate = 0; will be done by the caller */
 212     return 2;
 213   } else
 214     return 0;
 215 }