enc/big5.c

   1 /**********************************************************************
   2   big5.c -  Oniguruma (regular expression library)
   3 **********************************************************************/
   4 /*-
   5  * Copyright (c) 2002-2007  K.Kosako  <sndgk393 AT ybb DOT ne DOT jp>
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #include "regenc.h"
  31
  32 static const int EncLen_BIG5[] = {
  33   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  34   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  35   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  36   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  37   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  38   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  39   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  40   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  41   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  42   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  43   1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
  44   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
  45   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
  46   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
  47   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
  48   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1
  49 };
  50
  51 typedef enum { FAILURE = -2, ACCEPT = -1, S0 = 0, S1 } state_t;
  52 #define A ACCEPT
  53 #define F FAILURE
  54 static const signed char trans[][0x100] = {
  55   { /* S0   0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f */
  56     /* 0 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  57     /* 1 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  58     /* 2 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  59     /* 3 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  60     /* 4 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  61     /* 5 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  62     /* 6 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  63     /* 7 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  64     /* 8 */ F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F,
  65     /* 9 */ F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F,
  66     /* a */ F, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  67     /* b */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  68     /* c */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  69     /* d */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  70     /* e */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  71     /* f */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, F
  72   },
  73   { /* S1   0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f */
  74     /* 0 */ F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F,
  75     /* 1 */ F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F,
  76     /* 2 */ F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F,
  77     /* 3 */ F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F,
  78     /* 4 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  79     /* 5 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  80     /* 6 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  81     /* 7 */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, F,
  82     /* 8 */ F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F,
  83     /* 9 */ F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F,
  84     /* a */ F, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  85     /* b */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  86     /* c */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  87     /* d */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  88     /* e */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, A,
  89     /* f */ A, A, A, A, A, A, A, A, A, A, A, A, A, A, A, F
  90   }
  91 };
  92 #undef A
  93 #undef F
  94
  95 static int
  96 big5_mbc_enc_len(const UChar* p, const UChar* e, OnigEncoding enc ARG_UNUSED)
  97 {
  98   int firstbyte = *p++;
  99   state_t s = trans[0][firstbyte];
 100 #define RETURN(n) \
 101     return s == ACCEPT ? ONIGENC_CONSTRUCT_MBCLEN_CHARFOUND(n) : \
 102                          ONIGENC_CONSTRUCT_MBCLEN_INVALID()
 103   if (s < 0) RETURN(1);
 104   if (p == e) return ONIGENC_CONSTRUCT_MBCLEN_NEEDMORE(EncLen_BIG5[firstbyte]-1);
 105   s = trans[s][*p++];
 106   RETURN(2);
 107 #undef RETURN
 108 }
 109
 110 static OnigCodePoint
 111 big5_mbc_to_code(const UChar* p, const UChar* end, OnigEncoding enc)
 112 {
 113   return onigenc_mbn_mbc_to_code(enc, p, end);
 114 }
 115
 116 static int
 117 big5_code_to_mbc(OnigCodePoint code, UChar *buf, OnigEncoding enc)
 118 {
 119   return onigenc_mb2_code_to_mbc(enc, code, buf);
 120 }
 121
 122 static int
 123 big5_mbc_case_fold(OnigCaseFoldType flag, const UChar** pp, const UChar* end,
 124                    UChar* lower, OnigEncoding enc)
 125 {
 126   return onigenc_mbn_mbc_case_fold(enc, flag,
 127                                    pp, end, lower);
 128 }
 129
 130 #if 0
 131 static int
 132 big5_is_mbc_ambiguous(OnigCaseFoldType flag,
 133                       const UChar** pp, const UChar* end, OnigEncoding enc)
 134 {
 135   return onigenc_mbn_is_mbc_ambiguous(enc, flag, pp, end);
 136 }
 137 #endif
 138
 139 static int
 140 big5_is_code_ctype(OnigCodePoint code, unsigned int ctype, OnigEncoding enc)
 141 {
 142   return onigenc_mb2_is_code_ctype(enc, code, ctype);
 143 }
 144
 145 static const char BIG5_CAN_BE_TRAIL_TABLE[256] = {
 146   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 147   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 148   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 149   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 150   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 151   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 152   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 153   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0,
 154   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 155   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 156   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 157   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 158   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 159   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 160   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 161   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0
 162 };
 163
 164 #define BIG5_ISMB_FIRST(byte)  (EncLen_BIG5[byte] > 1)
 165 #define BIG5_ISMB_TRAIL(byte)  BIG5_CAN_BE_TRAIL_TABLE[(byte)]
 166
 167 static UChar*
 168 big5_left_adjust_char_head(const UChar* start, const UChar* s, OnigEncoding enc)
 169 {
 170   const UChar *p;
 171   int len;
 172
 173   if (s <= start) return (UChar* )s;
 174   p = s;
 175
 176   if (BIG5_ISMB_TRAIL(*p)) {
 177     while (p > start) {
 178       if (! BIG5_ISMB_FIRST(*--p)) {
 179         p++;
 180         break;
 181       }
 182     }
 183   }
 184   len = enclen(enc, p, s);
 185   if (p + len > s) return (UChar* )p;
 186   p += len;
 187   return (UChar* )(p + ((s - p) & ~1));
 188 }
 189
 190 static int
 191 big5_is_allowed_reverse_match(const UChar* s, const UChar* end ARG_UNUSED, OnigEncoding enc ARG_UNUSED)
 192 {
 193   const UChar c = *s;
 194
 195   return (BIG5_ISMB_TRAIL(c) ? FALSE : TRUE);
 196 }
 197
 198 OnigEncodingDefine(big5, BIG5) = {
 199   big5_mbc_enc_len,
 200   "Big5",     /* name */
 201   2,          /* max enc length */
 202   1,          /* min enc length */
 203   onigenc_is_mbc_newline_0x0a,
 204   big5_mbc_to_code,
 205   onigenc_mb2_code_to_mbclen,
 206   big5_code_to_mbc,
 207   big5_mbc_case_fold,
 208   onigenc_ascii_apply_all_case_fold,
 209   onigenc_ascii_get_case_fold_codes_by_str,
 210   onigenc_minimum_property_name_to_ctype,
 211   big5_is_code_ctype,
 212   onigenc_not_support_get_ctype_code_range,
 213   big5_left_adjust_char_head,
 214   big5_is_allowed_reverse_match
 215 };
 216 ENC_ALIAS("CP950", "BIG5");