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:
Big5Decoder()17   Big5Decoder() { }
18   size_t decode(Char *, const char *, size_t, const char **);
19 private:
20 };
21 
22 class Big5Encoder : public Encoder {
23 public:
Big5Encoder()24   Big5Encoder() { }
25   void output(const Char *, size_t, OutputByteStream *);
output(Char * tmp_char,size_t tmp_size_t,OutputByteStream * tmp_obs)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 
makeDecoder() const32 Decoder *Big5CodingSystem::makeDecoder() const
33 {
34   return new Big5Decoder;
35 }
36 
makeEncoder() const37 Encoder *Big5CodingSystem::makeEncoder() const
38 {
39   return new Big5Encoder;
40 }
41 
decode(Char * to,const char * s,size_t slen,const char ** rest)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 
output(const Char * s,size_t n,OutputByteStream * sb)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 */
91