source/iso2022jp.cpp

   1 /* $Id$
   2
   3 This file is part of libmspstrings
   4 Copyright © 2006-2007 Mikko Rasa
   5 Distributed under the LGPL
   6 */
   7
   8 #include "ascii.h"
   9 #include "iso2022jp.h"
  10 #include "jisx0201.h"
  11 #include "jisx0208.h"
  12
  13 using namespace std;
  14
  15 namespace Msp {
  16
  17 void Iso2022Jp::Encoder::encode_char(wchar_t c_)
  18 {
  19         // Win32 has typedef unsigned short wchar_t
  20         int c=c_;
  21
  22         if(c>=0 && c<=0x7F && c!=0x5C && c!=0x7E)
  23         {
  24                 if(mode!=ASCII && mode!=JISX0201)
  25                         switch_mode(ASCII);
  26                 append(c);
  27         }
  28         else if(c==0x5C || c==0x7E)
  29         {
  30                 if(mode!=ASCII)
  31                         switch_mode(ASCII);
  32                 append(c);
  33         }
  34         else if(c==0xA5 || c==0x203E)
  35         {
  36                 if(mode!=JISX0201)
  37                         switch_mode(JISX0201);
  38                 if(c==0xA5)
  39                         append(0x5C);
  40                 else if(c==0x203E)
  41                         append(0x7E);
  42         }
  43         else
  44         {
  45                 unsigned short jis=ucs_to_jisx0208(c);
  46                 if(!jis)
  47                         error("Can't express character in ISO-2022-JP");
  48                 else
  49                 {
  50                         if(mode!=JISX0208)
  51                                 switch_mode(JISX0208);
  52
  53                         char buf[2]={jis>>8, jis};
  54                         append(buf, 2);
  55                 }
  56         }
  57 }
  58
  59 void Iso2022Jp::Encoder::sync()
  60 {
  61         if(mode!=ASCII)
  62                 switch_mode(ASCII);
  63 }
  64
  65 void Iso2022Jp::Encoder::switch_mode(Mode m)
  66 {
  67         mode=m;
  68         switch(mode)
  69         {
  70         case ASCII:    append("\033(B", 3); break;
  71         case JISX0201: append("\033(J", 3); break;
  72         case JISX0208: append("\033$B", 3); break;
  73         }
  74 }
  75
  76 void Iso2022Jp::Encoder::append_replacement()
  77 {
  78         if(mode!=ASCII)
  79                 switch_mode(ASCII);
  80         append(032);
  81 }
  82
  83 Iso2022Jp::Decoder::Decoder(ErrorMode em):
  84         StringCodec::Decoder(em),
  85         mode(ASCII),
  86         dec(new Ascii::Decoder),
  87         escape(0)
  88 { }
  89
  90 void Iso2022Jp::Decoder::decode_char(const string &str, string::const_iterator &i)
  91 {
  92         while(i!=str.end())
  93         {
  94                 if(escape)
  95                 {
  96                         escape=escape<<8 | static_cast<unsigned char>(*i);
  97                         if(*i>='@' && *i<='Z')
  98                         {
  99                                 switch(escape)
 100                                 {
 101                                 case 0x1B2842: switch_mode(ASCII); break;    // ESC ( B
 102                                 case 0x1B284A: switch_mode(JISX0201); break; // ESC ( J
 103                                 case 0x1B2440:                               // ESC $ @
 104                                 case 0x1B2442: switch_mode(JISX0208); break; // ESC $ B
 105                                 default: error("Invalid ISO-2022-JP escape sequence");
 106                                 }
 107                                 escape=0;
 108                         }
 109                         ++i;
 110                 }
 111                 else if(*i==0x1B)
 112                 {
 113                         escape=0x1B;
 114                         ++i;
 115                 }
 116                 else
 117                 {
 118                         dec->decode_char(str, i);
 119                         break;
 120                 }
 121         }
 122 }
 123
 124 void Iso2022Jp::Decoder::sync()
 125 {
 126         if(escape)
 127         {
 128                 error("Sync in middle of ISO-2022-JP escape sequence");
 129                 escape=0;
 130         }
 131
 132         if(mode!=ASCII)
 133         {
 134                 error("Sync while not in ASCII mode");
 135                 switch_mode(ASCII);
 136         }
 137         else
 138         {
 139                 append(dec->get());
 140                 dec->flush();
 141         }
 142 }
 143
 144 void Iso2022Jp::Decoder::switch_mode(Mode m)
 145 {
 146         append(dec->get());
 147         delete dec;
 148
 149         mode=m;
 150         switch(mode)
 151         {
 152         case ASCII: dec=new Ascii::Decoder; break;
 153         case JISX0201: dec=new JisX0201::Decoder; break;
 154         case JISX0208: dec=new JisX0208::Decoder; break;
 155         }
 156 }
 157
 158 } // namespace Msp