source/stringcodec/iso2022jp.cpp

   1 #include "ascii.h"
   2 #include "iso2022jp.h"
   3 #include "jisx0201.h"
   4 #include "jisx0208.h"
   5
   6 using namespace std;
   7
   8 namespace Msp {
   9 namespace StringCodec {
  10
  11 void Iso2022Jp::Encoder::encode_char(unichar ch, string &buf)
  12 {
  13         if(ch>=0 && ch<=0x7F && ch!=0x5C && ch!=0x7E)
  14         {
  15                 if(mode!=ASCII && mode!=JISX0201)
  16                         switch_mode(ASCII, buf);
  17                 buf += ch;
  18         }
  19         else if(ch==0x5C || ch==0x7E)
  20         {
  21                 if(mode!=ASCII)
  22                         switch_mode(ASCII, buf);
  23                 buf += ch;
  24         }
  25         else if(ch==0xA5 || ch==0x203E)
  26         {
  27                 if(mode!=JISX0201)
  28                         switch_mode(JISX0201, buf);
  29                 if(ch==0xA5)
  30                         buf += 0x5C;
  31                 else if(ch==0x203E)
  32                         buf += 0x7E;
  33         }
  34         else
  35         {
  36                 Kuten jis = ucs_to_jisx0208(ch);
  37                 if(!jis)
  38                         return error(ch, buf, invalid_character(ch, "ISO-2022-JP"));
  39
  40                 if(mode!=JISX0208)
  41                         switch_mode(JISX0208, buf);
  42
  43                 char jbuf[2];
  44                 jbuf[0] = jis.ku+0x20;
  45                 jbuf[1] = jis.ten+0x20;
  46                 buf.append(jbuf, 2);
  47         }
  48 }
  49
  50 void Iso2022Jp::Encoder::sync(string &buf)
  51 {
  52         if(mode!=ASCII)
  53                 switch_mode(ASCII, buf);
  54 }
  55
  56 void Iso2022Jp::Encoder::reset()
  57 {
  58         mode = ASCII;
  59 }
  60
  61 void Iso2022Jp::Encoder::switch_mode(Mode m, string &buf)
  62 {
  63         mode = m;
  64         switch(mode)
  65         {
  66         case ASCII:    buf.append("\033(B", 3); break;
  67         case JISX0201: buf.append("\033(J", 3); break;
  68         case JISX0208: buf.append("\033$B", 3); break;
  69         default: throw invalid_argument("Iso2022Jp::Encoder::switch_mode");
  70         }
  71 }
  72
  73 void Iso2022Jp::Encoder::transliterate(unichar, string &buf)
  74 {
  75         if(mode!=ASCII)
  76                 switch_mode(ASCII, buf);
  77         buf += '?';
  78 }
  79
  80
  81 Iso2022Jp::Decoder::Decoder(ErrorMode em):
  82         Codec::Decoder(em),
  83         dec(new Ascii::Decoder)
  84 { }
  85
  86 unichar Iso2022Jp::Decoder::decode_char(const string &str, string::const_iterator &i)
  87 {
  88         if(i==str.end())
  89                 return -1;
  90
  91         while(i!=str.end())
  92         {
  93                 auto j = i;
  94
  95                 unichar result = -1;
  96                 if(*j==033)
  97                 {
  98                         unsigned escape = 0;
  99                         for(++j; j!=str.end(); ++j)
 100                         {
 101                                 escape = escape<<8 | static_cast<unsigned char>(*j);
 102                                 if(*j>='@' && *j<='Z')
 103                                         break;
 104                         }
 105
 106                         bool ok = true;
 107                         switch(escape)
 108                         {
 109                         case 0x2842: switch_mode(ASCII); break;    // ESC ( B
 110                         case 0x284A: switch_mode(JISX0201); break; // ESC ( J
 111                         case 0x2440:                               // ESC $ @
 112                         case 0x2442: switch_mode(JISX0208); break; // ESC $ B
 113                         default: ok = false;
 114                         }
 115
 116                         if(ok)
 117                                 i = j;
 118                         else
 119                                 result = *i;
 120                         ++i;
 121                 }
 122                 else if(dec)
 123                         return dec->decode_char(str, i);
 124                 else
 125                         throw logic_error("no sub-decoder");
 126
 127                 if(result>=0)
 128                         return result;
 129         }
 130
 131         return -1;
 132 }
 133
 134 void Iso2022Jp::Decoder::reset()
 135 {
 136         delete dec;
 137         mode = ASCII;
 138         dec = new Ascii::Decoder;
 139 }
 140
 141 void Iso2022Jp::Decoder::switch_mode(Mode m)
 142 {
 143         delete dec;
 144
 145         mode = m;
 146         switch(mode)
 147         {
 148         case ASCII: dec = new Ascii::Decoder; break;
 149         case JISX0201: dec = new JisX0201::Decoder; break;
 150         case JISX0208: dec = new JisX0208::Decoder; break;
 151         }
 152 }
 153
 154 } // namespace StringCodec
 155 } // namespace Msp