1 /*
2 	following astonishing goo courtesy of kogure.
3 */
4 /*
5  * MicroSoft Kanji Encoding (SJIS) Transformation
6  */
7 
8 /*
9  * void
10  * J2S(unsigned char *_h, unsigned char *_l)
11  *	JIS X 208 to MS kanji transformation.
12  *
13  * Calling/Exit State:
14  *	_h and _l should be in their valid range.
15  *	No return value.
16  */
17 #define J2S(_h, _l) { \
18 	/* lower: 21-7e >> 40-9d,9e-fb >> 40-7e,(skip 7f),80-fc */ \
19 	if (((_l) += (((_h)-- % 2) ? 0x1f : 0x7d)) > 0x7e) (_l)++; \
20 	/* upper: 21-7e >> 81-af >> 81-9f,(skip a0-df),e0-ef */ \
21 	if (((_h) = ((_h) / 2 + 0x71)) > 0x9f) (_h) += 0x40; \
22 }
23 
24 /*
25  * void
26  * S2J(unsigned char *_h, unsigned char *_l)
27  *	MS kanji to JIS X 208 transformation.
28  *
29  * Calling/Exit State:
30  *	_h and _l should be in valid range.
31  *	No return value.
32  */
33 #define S2J(_h, _l) { \
34 	/* lower: 40-7e,80-fc >> 21-5f,61-dd >> 21-7e,7f-dc */ \
35 	if (((_l) -= 0x1f) > 0x60) (_l)--; \
36 	/* upper: 81-9f,e0-ef >> 00-1e,5f-6e >> 00-2e >> 21-7d */ \
37 	if (((_h) -= 0x81) > 0x5e) (_h) -= 0x40; (_h) *= 2, (_h) += 0x21; \
38 	/* upper: ,21-7d >> ,22-7e ; lower: ,7f-dc >> ,21-7e */ \
39 	if ((_l) > 0x7e) (_h)++, (_l) -= 0x5e; \
40 }
41 
42 /*
43  * int
44  * ISJKANA(const unsigned char *_b)
45  *	Tests given byte is in the range of JIS X 0201 katakana.
46  *
47  * Calling/Exit State:
48  *	Returns 1 if it is, or 0 otherwise.
49  */
50 #define	ISJKANA(_b)	(0xa0 <= (_b) && (_b) < 0xe0)
51 
52 /*
53  * int
54  * CANS2JH(const unsigned char *_h)
55  *	Tests given byte is in the range of valid first byte of MS
56  *	kanji code; either acts as a subroutine of CANS2J() macro
57  *	or can be used to parse MS kanji encoded strings.
58  *
59  * Calling/Exit State:
60  *	Returns 1 if it is, or 0 otherwise.
61  */
62 #define CANS2JH(_h)	((0x81 <= (_h) && (_h) < 0xf0) && !ISJKANA(_h))
63 
64 /*
65  * int
66  * CANS2JL(const unsigned char *_l)
67  *	Tests given byte is in the range of valid second byte of MS
68  *	kanji code; acts as a subroutine of CANS2J() macro.
69  *
70  * Calling/Exit State:
71  *	Returns 1 if it is, or 0 otherwise.
72  */
73 #define CANS2JL(_l)	(0x40 <= (_l) && (_l) < 0xfd && (_l) != 0x7f)
74 
75 /*
76  * int
77  * CANS2J(const unsigned char *_h, const unsinged char *_l)
78  *	Tests given bytes form a MS kanji code point which can be
79  *	transformed to a valid JIS X 208 code point.
80  *
81  * Calling/Exit State:
82  *	Returns 1 if they are, or 0 otherwise.
83  */
84 #define CANS2J(_h, _l)  (CANS2JH(_h) && CANS2JL(_l))
85 
86 /*
87  * int
88  * CANJ2SB(const unsigned char *_b)
89  *	Tests given bytes is in the range of valid 94 graphic
90  *	character set; acts as a subroutine of CANJ2S() macro.
91  *
92  * Calling/Exit State:
93  *	Returns 1 if it is, or 0 otherwise.
94  */
95 #define CANJ2SB(_b)	(0x21 <= (_b) && (_b) < 0x7f)
96 
97 /*
98  * int
99  * CANJ2S(const unsigned char *_h, const unsigned char *_l)
100  *	Tests given bytes form valid JIS X 208 code points
101  *	(which can be transformed to MS kanji).
102  *
103  * Calling/Exit State:
104  *	Returns 1 if they are, or 0 otherwise.
105  */
106 #define CANJ2S(_h, _l)	(CANJ2SB(_h) && CANJ2SB(_l))
107 
108 #define		JIS208MAX	8407
109 #define		GB2312MAX	8795
110 #define		BIG5MAX		13973
111 
112 extern Rune tabjis208[JIS208MAX];	/* runes indexed by kuten */
113 extern Rune tabgb2312[GB2312MAX];
114 extern Rune tabbig5[BIG5MAX];
115