summaryrefslogtreecommitdiffstats
path: root/Modules/cjkcodecs/_codecs_hk.c
blob: aaf103db888bc0a0a20b2f78a193144f84a4b5eb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
/*
 * _codecs_hk.c: Codecs collection for encodings from Hong Kong
 *
 * Written by Hye-Shik Chang <perky@FreeBSD.org>
 */

#define USING_IMPORTED_MAPS

#include "cjkcodecs.h"
#include "mappings_hk.h"

/*
 * BIG5HKSCS codec
 */

static const encode_map *big5_encmap = NULL;
static const decode_map *big5_decmap = NULL;

CODEC_INIT(big5hkscs)
{
    static int initialized = 0;

    if (!initialized && IMPORT_MAP(tw, big5, &big5_encmap, &big5_decmap))
        return -1;
    initialized = 1;
    return 0;
}

/*
 * There are four possible pair unicode -> big5hkscs maps as in HKSCS 2004:
 *  U+00CA U+0304 -> 8862  (U+00CA alone is mapped to 8866)
 *  U+00CA U+030C -> 8864
 *  U+00EA U+0304 -> 88a3  (U+00EA alone is mapped to 88a7)
 *  U+00EA U+030C -> 88a5
 * These are handled by not mapping tables but a hand-written code.
 */
static const DBCHAR big5hkscs_pairenc_table[4] = {0x8862, 0x8864, 0x88a3, 0x88a5};

ENCODER(big5hkscs)
{
    while (inleft > 0) {
        ucs4_t c = **inbuf;
        DBCHAR code;
        Py_ssize_t insize;

        if (c < 0x80) {
            REQUIRE_OUTBUF(1)
            **outbuf = (unsigned char)c;
            NEXT(1, 1)
            continue;
        }

        DECODE_SURROGATE(c)
        insize = GET_INSIZE(c);

        REQUIRE_OUTBUF(2)

        if (c < 0x10000) {
            TRYMAP_ENC(big5hkscs_bmp, code, c) {
                if (code == MULTIC) {
                    if (inleft >= 2 &&
                        ((c & 0xffdf) == 0x00ca) &&
                        (((*inbuf)[1] & 0xfff7) == 0x0304)) {
                        code = big5hkscs_pairenc_table[
                            ((c >> 4) |
                             ((*inbuf)[1] >> 3)) & 3];
                        insize = 2;
                    }
                    else if (inleft < 2 &&
                             !(flags & MBENC_FLUSH))
                        return MBERR_TOOFEW;
                    else {
                        if (c == 0xca)
                            code = 0x8866;
                        else /* c == 0xea */
                            code = 0x88a7;
                    }
                }
            }
            else TRYMAP_ENC(big5, code, c);
            else return 1;
        }
        else if (c < 0x20000)
            return insize;
        else if (c < 0x30000) {
            TRYMAP_ENC(big5hkscs_nonbmp, code, c & 0xffff);
            else return insize;
        }
        else
            return insize;

        OUT1(code >> 8)
        OUT2(code & 0xFF)
        NEXT(insize, 2)
    }

    return 0;
}

#define BH2S(c1, c2) (((c1) - 0x87) * (0xfe - 0x40 + 1) + ((c2) - 0x40))

DECODER(big5hkscs)
{
    while (inleft > 0) {
        unsigned char c = IN1;
        ucs4_t decoded;

        REQUIRE_OUTBUF(1)

        if (c < 0x80) {
            OUT1(c)
            NEXT(1, 1)
            continue;
        }

        REQUIRE_INBUF(2)

        if (0xc6 <= c && c <= 0xc8 && (c >= 0xc7 || IN2 >= 0xa1))
            goto hkscsdec;

        TRYMAP_DEC(big5, **outbuf, c, IN2) {
            NEXT(2, 1)
        }
        else
hkscsdec:       TRYMAP_DEC(big5hkscs, decoded, c, IN2) {
                        int s = BH2S(c, IN2);
                        const unsigned char *hintbase;

                        assert(0x87 <= c && c <= 0xfe);
                        assert(0x40 <= IN2 && IN2 <= 0xfe);

                        if (BH2S(0x87, 0x40) <= s && s <= BH2S(0xa0, 0xfe)) {
                                hintbase = big5hkscs_phint_0;
                                s -= BH2S(0x87, 0x40);
                        }
                        else if (BH2S(0xc6,0xa1) <= s && s <= BH2S(0xc8,0xfe)){
                                hintbase = big5hkscs_phint_12130;
                                s -= BH2S(0xc6, 0xa1);
                        }
                        else if (BH2S(0xf9,0xd6) <= s && s <= BH2S(0xfe,0xfe)){
                                hintbase = big5hkscs_phint_21924;
                                s -= BH2S(0xf9, 0xd6);
                        }
                        else
                                return MBERR_INTERNAL;

                        if (hintbase[s >> 3] & (1 << (s & 7))) {
                                WRITEUCS4(decoded | 0x20000)
                                NEXT_IN(2)
                        }
                        else {
                                OUT1(decoded)
                                NEXT(2, 1)
                        }
                }
                else {
                        switch ((c << 8) | IN2) {
                        case 0x8862: WRITE2(0x00ca, 0x0304); break;
                        case 0x8864: WRITE2(0x00ca, 0x030c); break;
                        case 0x88a3: WRITE2(0x00ea, 0x0304); break;
                        case 0x88a5: WRITE2(0x00ea, 0x030c); break;
                        default: return 2;
                        }

                        NEXT(2, 2) /* all decoded codepoints are pairs, above. */
        }
    }

    return 0;
}


BEGIN_MAPPINGS_LIST
  MAPPING_DECONLY(big5hkscs)
  MAPPING_ENCONLY(big5hkscs_bmp)
  MAPPING_ENCONLY(big5hkscs_nonbmp)
END_MAPPINGS_LIST

BEGIN_CODECS_LIST
  CODEC_STATELESS_WINIT(big5hkscs)
END_CODECS_LIST

I_AM_A_MODULE_FOR(hk)