source/stringcodec/jisx0208.cpp

   1 #include "jisx0208.h"
   2
   3 #include "jisx0208.table"
   4
   5 using namespace std;
   6
   7 namespace Msp {
   8 namespace StringCodec {
   9
  10 void JisX0208::Encoder::encode_char(unichar ucs, string &buf)
  11 {
  12         unsigned short jis = ucs_to_jisx0208(ucs);
  13         if(jis)
  14         {
  15                 char jbuf[2] = {jis>>8, jis};
  16                 buf.append(jbuf, 2);
  17         }
  18         else
  19                 error(ucs, buf, invalid_character(ucs, "JIS X 0208"));
  20 }
  21
  22 void JisX0208::Encoder::transliterate(unichar, string &buf)
  23 {
  24         buf.append("!)", 2);
  25 }
  26
  27
  28 unichar JisX0208::Decoder::decode_char(const string &str, string::const_iterator &i)
  29 {
  30         if(i==str.end())
  31                 return -1;
  32
  33         string::const_iterator j = i;
  34         Kuten jis;
  35         jis.ku = *j++-0x20;
  36
  37         unichar result;
  38         if(j==str.end())
  39                 result = error(invalid_sequence(i, j, "incomplete JIS X 0208 character"));
  40         else
  41         {
  42                 jis.ten = *j++-0x20;
  43                 result = jisx0208_to_ucs(jis);
  44                 if(result==-1)
  45                         result = error(invalid_sequence(i, j, "invalid JIS X 0208 ku-ten"));
  46                 if(result==0)
  47                         result = error(invalid_sequence(i, j, "undefined JIS X 0208 character"));
  48         }
  49
  50         i = j;
  51         return result;
  52 }
  53
  54
  55 unichar jisx0208_to_ucs(Kuten jis)
  56 {
  57         if(jis.ku==0 || jis.ku>0x5E || jis.ten==0 || jis.ten>0x5E)
  58                 return -1;
  59
  60         return jisx0208_to_ucs_table[jis.ku*94 + jis.ten - 95];
  61 }
  62
  63 Kuten ucs_to_jisx0208(unichar c)
  64 {
  65         if(c<0 || c>0xFFFF)
  66                 return Kuten();
  67
  68         unsigned i = 0;
  69         for(unsigned bit=0x1000; bit; bit>>=1)
  70         {
  71                 if(i+bit>=ucs_to_jisx0208_table_size)
  72                         continue;
  73                 if(ucs_to_jisx0208_table[i+bit].ucs<=static_cast<unsigned short>(c))
  74                         i += bit;
  75         }
  76
  77         Kuten result;
  78         if(ucs_to_jisx0208_table[i].ucs==static_cast<unsigned short>(c))
  79         {
  80                 result.ku = (ucs_to_jisx0208_table[i].jis>>8)+1;
  81                 result.ten = ucs_to_jisx0208_table[i].jis+1;
  82         }
  83
  84         return result;
  85 }
  86
  87 } // namespace StringCodec
  88 } // namespace Msp