source/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
  10 void Iso2022Jp::Encoder::encode_char(wchar_t c)
  11 {
  12         if(c>=0 && c<=0x7F && c!=0x5C && c!=0x7E)
  13         {
  14                 if(mode!=ASCII && mode!=JISX0201)
  15                         switch_mode(ASCII);
  16                 append(c);
  17         }
  18         else if(c==0x5C || c==0x7E)
  19         {
  20                 if(mode!=ASCII)
  21                         switch_mode(ASCII);
  22                 append(c);
  23         }
  24         else if(c==0xA5 || c==0x203E)
  25         {
  26                 if(mode!=JISX0201)
  27                         switch_mode(JISX0201);
  28                 if(c==0xA5)
  29                         append(0x5C);
  30                 else if(c==0x203E)
  31                         append(0x7E);
  32         }
  33         else
  34         {
  35                 unsigned short jis=ucs_to_jisx0208(c);
  36                 if(!jis)
  37                         throw CodecError("Can't express character in ISO-2022-JP");
  38                 if(mode!=JISX0208)
  39                         switch_mode(JISX0208);
  40         }
  41 }
  42
  43 void Iso2022Jp::Encoder::switch_mode(Mode m)
  44 {
  45         mode=m;
  46         switch(mode)
  47         {
  48         case ASCII:    append("\033(B", 3); break;
  49         case JISX0201: append("\033(J", 3); break;
  50         case JISX0208: append("\033$B", 3); break;
  51         }
  52 }
  53
  54 Iso2022Jp::Decoder::Decoder():
  55         mode(ASCII),
  56         dec(new Ascii::Decoder),
  57         escape(0)
  58 { }
  59
  60 void Iso2022Jp::Decoder::decode_char(const string &str, string::const_iterator &i)
  61 {
  62         while(i!=str.end())
  63         {
  64                 if(escape)
  65                 {
  66                         escape=escape<<8 | (unsigned char)*i;
  67                         if(*i>='@' && *i<='Z')
  68                         {
  69                                 switch(escape)
  70                                 {
  71                                 case 0x1B2842: switch_mode(ASCII); break;    // ESC ( B
  72                                 case 0x1B284A: switch_mode(JISX0201); break; // ESC ( J
  73                                 case 0x1B2440:                               // ESC $ @
  74                                 case 0x1B2442: switch_mode(JISX0208); break; // ESC $ B
  75                                 default: throw CodecError("Invalid ISO-2022-JP escape sequence");
  76                                 }
  77                                 escape=0;
  78                         }
  79                         ++i;
  80                 }
  81                 else if(*i==0x1B)
  82                 {
  83                         escape=0x1B;
  84                         ++i;
  85                 }
  86                 else
  87                 {
  88                         dec->decode_char(str, i);
  89                         break;
  90                 }
  91         }
  92 }
  93
  94 void Iso2022Jp::Decoder::sync()
  95 {
  96         if(escape)
  97                 throw CodecError("Sync in middle of ISO-2022-JP escape sequence");
  98         if(mode!=ASCII)
  99                 throw CodecError("Sync while not in ASCII mode");
 100         append(dec->get());
 101         dec->flush();
 102 }
 103
 104 void Iso2022Jp::Decoder::switch_mode(Mode m)
 105 {
 106         append(dec->get());
 107         delete dec;
 108
 109         mode=m;
 110         switch(mode)
 111         {
 112         case ASCII: dec=new Ascii::Decoder; break;
 113         case JISX0201: dec=new JisX0201::Decoder; break;
 114         case JISX0208: dec=new JisX0208::Decoder; break;
 115         }
 116 }
 117
 118 } // namespace Msp