/Modules/cjkcodecs/_codecs_hk.c

  1/*
  2 * _codecs_hk.c: Codecs collection for encodings from Hong Kong
  3 *
  4 * Written by Hye-Shik Chang <perky@FreeBSD.org>
  5 */
  6
  7#define USING_IMPORTED_MAPS
  8
  9#include "cjkcodecs.h"
 10#include "mappings_hk.h"
 11
 12/*
 13 * BIG5HKSCS codec
 14 */
 15
 16static const encode_map *big5_encmap = NULL;
 17static const decode_map *big5_decmap = NULL;
 18
 19CODEC_INIT(big5hkscs)
 20{
 21	static int initialized = 0;
 22
 23	if (!initialized && IMPORT_MAP(tw, big5, &big5_encmap, &big5_decmap))
 24		return -1;
 25	initialized = 1;
 26	return 0;
 27}
 28
 29/*
 30 * There are four possible pair unicode -> big5hkscs maps as in HKSCS 2004:
 31 *  U+00CA U+0304 -> 8862  (U+00CA alone is mapped to 8866)
 32 *  U+00CA U+030C -> 8864
 33 *  U+00EA U+0304 -> 88a3  (U+00EA alone is mapped to 88a7)
 34 *  U+00EA U+030C -> 88a5
 35 * These are handled by not mapping tables but a hand-written code.
 36 */
 37static const DBCHAR big5hkscs_pairenc_table[4] = {0x8862, 0x8864, 0x88a3, 0x88a5};
 38
 39ENCODER(big5hkscs)
 40{
 41	while (inleft > 0) {
 42		ucs4_t c = **inbuf;
 43		DBCHAR code;
 44		Py_ssize_t insize;
 45
 46		if (c < 0x80) {
 47			REQUIRE_OUTBUF(1)
 48			**outbuf = (unsigned char)c;
 49			NEXT(1, 1)
 50			continue;
 51		}
 52
 53		DECODE_SURROGATE(c)
 54		insize = GET_INSIZE(c);
 55
 56		REQUIRE_OUTBUF(2)
 57
 58		if (c < 0x10000) {
 59			TRYMAP_ENC(big5hkscs_bmp, code, c) {
 60				if (code == MULTIC) {
 61					if (inleft >= 2 &&
 62					    ((c & 0xffdf) == 0x00ca) &&
 63					    (((*inbuf)[1] & 0xfff7) == 0x0304)) {
 64						code = big5hkscs_pairenc_table[
 65							((c >> 4) |
 66							 ((*inbuf)[1] >> 3)) & 3];
 67						insize = 2;
 68					}
 69					else if (inleft < 2 &&
 70						 !(flags & MBENC_FLUSH))
 71						return MBERR_TOOFEW;
 72					else {
 73						if (c == 0xca)
 74							code = 0x8866;
 75						else /* c == 0xea */
 76							code = 0x88a7;
 77					}
 78				}
 79			}
 80			else TRYMAP_ENC(big5, code, c);
 81			else return 1;
 82		}
 83		else if (c < 0x20000)
 84			return insize;
 85		else if (c < 0x30000) {
 86			TRYMAP_ENC(big5hkscs_nonbmp, code, c & 0xffff);
 87			else return insize;
 88		}
 89		else
 90			return insize;
 91
 92		OUT1(code >> 8)
 93		OUT2(code & 0xFF)
 94		NEXT(insize, 2)
 95	}
 96
 97	return 0;
 98}
 99
100#define BH2S(c1, c2) (((c1) - 0x87) * (0xfe - 0x40 + 1) + ((c2) - 0x40))
101
102DECODER(big5hkscs)
103{
104	while (inleft > 0) {
105		unsigned char c = IN1;
106		ucs4_t decoded;
107
108		REQUIRE_OUTBUF(1)
109
110		if (c < 0x80) {
111			OUT1(c)
112			NEXT(1, 1)
113			continue;
114		}
115
116		REQUIRE_INBUF(2)
117
118		if (0xc6 <= c && c <= 0xc8 && (c >= 0xc7 || IN2 >= 0xa1))
119			goto hkscsdec;
120
121		TRYMAP_DEC(big5, **outbuf, c, IN2) {
122			NEXT(2, 1)
123		}
124		else
125hkscsdec:	TRYMAP_DEC(big5hkscs, decoded, c, IN2) {
126			int s = BH2S(c, IN2);
127			const unsigned char *hintbase;
128
129			assert(0x87 <= c && c <= 0xfe);
130			assert(0x40 <= IN2 && IN2 <= 0xfe);
131
132			if (BH2S(0x87, 0x40) <= s && s <= BH2S(0xa0, 0xfe)) {
133				hintbase = big5hkscs_phint_0;
134				s -= BH2S(0x87, 0x40);
135			}
136			else if (BH2S(0xc6,0xa1) <= s && s <= BH2S(0xc8,0xfe)){
137				hintbase = big5hkscs_phint_12130;
138				s -= BH2S(0xc6, 0xa1);
139			}
140			else if (BH2S(0xf9,0xd6) <= s && s <= BH2S(0xfe,0xfe)){
141				hintbase = big5hkscs_phint_21924;
142				s -= BH2S(0xf9, 0xd6);
143			}
144			else
145				return MBERR_INTERNAL;
146
147			if (hintbase[s >> 3] & (1 << (s & 7))) {
148				WRITEUCS4(decoded | 0x20000)
149				NEXT_IN(2)
150			}
151			else {
152				OUT1(decoded)
153				NEXT(2, 1)
154			}
155		}
156		else {
157			switch ((c << 8) | IN2) {
158			case 0x8862: WRITE2(0x00ca, 0x0304); break;
159			case 0x8864: WRITE2(0x00ca, 0x030c); break;
160			case 0x88a3: WRITE2(0x00ea, 0x0304); break;
161			case 0x88a5: WRITE2(0x00ea, 0x030c); break;
162			default: return 2;
163			}
164
165			NEXT(2, 2) /* all decoded codepoints are pairs, above. */
166		}
167	}
168
169	return 0;
170}
171
172
173BEGIN_MAPPINGS_LIST
174  MAPPING_DECONLY(big5hkscs)
175  MAPPING_ENCONLY(big5hkscs_bmp)
176  MAPPING_ENCONLY(big5hkscs_nonbmp)
177END_MAPPINGS_LIST
178
179BEGIN_CODECS_LIST
180  CODEC_STATELESS_WINIT(big5hkscs)
181END_CODECS_LIST
182
183I_AM_A_MODULE_FOR(hk)