usr/src/cmd/man/src/util/nsgmls.src/lib/Big5CodingSystem.cxx

   1 // Copyright (c) 1997 James Clark
   2 // See the file COPYING for copying permission.
   3 #pragma ident   "%Z%%M% %I%     %E% SMI"
   4
   5 #include "splib.h"
   6
   7 #ifdef SP_MULTI_BYTE
   8
   9 #include "Big5CodingSystem.h"
  10
  11 #ifdef SP_NAMESPACE
  12 namespace SP_NAMESPACE {
  13 #endif
  14
  15 class Big5Decoder : public Decoder {
  16 public:
  17   Big5Decoder() { }
  18   size_t decode(Char *, const char *, size_t, const char **);
  19 private:
  20 };
  21
  22 class Big5Encoder : public Encoder {
  23 public:
  24   Big5Encoder() { }
  25   void output(const Char *, size_t, OutputByteStream *);
  26   void output(Char *tmp_char, size_t tmp_size_t, OutputByteStream *tmp_obs) {
  27         output((const Char *)tmp_char, (size_t) tmp_size_t, (OutputByteStream *)tmp_obs);
  28   }
  29
  30 };
  31
  32 Decoder *Big5CodingSystem::makeDecoder() const
  33 {
  34   return new Big5Decoder;
  35 }
  36
  37 Encoder *Big5CodingSystem::makeEncoder() const
  38 {
  39   return new Big5Encoder;
  40 }
  41
  42 size_t Big5Decoder::decode(Char *to, const char *s,
  43                            size_t slen, const char **rest)
  44 {
  45   Char *start = to;
  46   const unsigned char *us = (const unsigned char *)s;
  47   while (slen > 0) {
  48     if (!(*us & 0x80)) {
  49       *to++ = *us++;
  50       slen--;
  51     }
  52     else {
  53       if (slen < 2)
  54         break;
  55       slen -= 2;
  56       unsigned short n = *us++ << 8;
  57       n |= *us++;
  58       *to++ = n;
  59     }
  60   }
  61   *rest = (const char *)us;
  62   return to - start;
  63 }
  64
  65 void Big5Encoder::output(const Char *s, size_t n, OutputByteStream *sb)
  66 {
  67   for (; n > 0; s++, n--) {
  68     Char c = *s;
  69     if (c < 0x80)
  70       sb->sputc((unsigned char)c);
  71     else if (c & 0x8000) {
  72       sb->sputc((unsigned char)(c >> 8));
  73       sb->sputc((unsigned char)(c & 0xff));
  74     }
  75     else
  76       handleUnencodable(c, sb);
  77   }
  78 }
  79
  80 #ifdef SP_NAMESPACE
  81 }
  82 #endif
  83
  84 #else /* not SP_MULTI_BYTE */
  85
  86 #ifndef __GNUG__
  87 static char non_empty_translation_unit; // sigh
  88 #endif
  89
  90 #endif /* not SP_MULTI_BYTE */