1 /*
2 * Copyright (C) 1999-2002, 2006 Free Software Foundation, Inc.
3 * This file is part of the GNU LIBICONV Library.
4 *
5 * The GNU LIBICONV Library is free software; you can redistribute it
6 * and/or modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either version 2
8 * of the License, or (at your option) any later version.
9 *
10 * The GNU LIBICONV Library is distributed in the hope that it will be
11 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
14 *
15 * You should have received a copy of the GNU Library General Public
16 * License along with the GNU LIBICONV Library; see the file COPYING.LIB.
17 * If not, write to the Free Software Foundation, Inc., 51 Franklin Street,
18 * Fifth Floor, Boston, MA 02110-1301, USA.
19 */
20
21 /*
22 * BIG5-HKSCS:1999
23 */
24
25 /*
26 * BIG5-HKSCS:1999 can be downloaded from
27 * http://www.info.gov.hk/digital21/eng/hkscs/download.html
28 * http://www.info.gov.hk/digital21/eng/hkscs/index.html
29 *
30 * It extends BIG5 (without the rows 0xC6..0xC7) through the ranges
31 *
32 * 0x{88..8D}{40..7E,A1..FE} 641 characters
33 * 0x{8E..A0}{40..7E,A1..FE} 2898 characters
34 * 0x{C6..C8}{40..7E,A1..FE} 359 characters
35 * 0xF9{D6..FE} 41 characters
36 * 0x{FA..FE}{40..7E,A1..FE} 763 characters
37 *
38 * Note that some HKSCS characters are not contained in Unicode 3.2
39 * and are therefore best represented as sequences of Unicode characters:
40 * 0x8862 U+00CA U+0304 LATIN CAPITAL LETTER E WITH CIRCUMFLEX AND MACRON
41 * 0x8864 U+00CA U+030C LATIN CAPITAL LETTER E WITH CIRCUMFLEX AND CARON
42 * 0x88A3 U+00EA U+0304 LATIN SMALL LETTER E WITH CIRCUMFLEX AND MACRON
43 * 0x88A5 U+00EA U+030C LATIN SMALL LETTER E WITH CIRCUMFLEX AND CARON
44 */
45
46 #include "hkscs1999.h"
47 #include "flushwc.h"
48
49 static int
big5hkscs1999_mbtowc(conv_t conv,ucs4_t * pwc,const unsigned char * s,int n)50 big5hkscs1999_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n)
51 {
52 ucs4_t last_wc = conv->istate;
53 if (last_wc) {
54 /* Output the buffered character. */
55 conv->istate = 0;
56 *pwc = last_wc;
57 return 0; /* Don't advance the input pointer. */
58 } else {
59 unsigned char c = *s;
60 /* Code set 0 (ASCII) */
61 if (c < 0x80)
62 return ascii_mbtowc(conv,pwc,s,n);
63 /* Code set 1 (BIG5 extended) */
64 if (c >= 0xa1 && c < 0xff) {
65 if (n < 2)
66 return RET_TOOFEW(0);
67 {
68 unsigned char c2 = s[1];
69 if ((c2 >= 0x40 && c2 < 0x7f) || (c2 >= 0xa1 && c2 < 0xff)) {
70 if (!((c == 0xc6 && c2 >= 0xa1) || c == 0xc7)) {
71 int ret = big5_mbtowc(conv,pwc,s,2);
72 if (ret != RET_ILSEQ)
73 return ret;
74 }
75 }
76 }
77 }
78 {
79 int ret = hkscs1999_mbtowc(conv,pwc,s,n);
80 if (ret != RET_ILSEQ)
81 return ret;
82 }
83 if (c == 0x88) {
84 if (n < 2)
85 return RET_TOOFEW(0);
86 {
87 unsigned char c2 = s[1];
88 if (c2 == 0x62 || c2 == 0x64 || c2 == 0xa3 || c2 == 0xa5) {
89 /* It's a composed character. */
90 ucs4_t wc1 = ((c2 >> 3) << 2) + 0x009a; /* = 0x00ca or 0x00ea */
91 ucs4_t wc2 = ((c2 & 6) << 2) + 0x02fc; /* = 0x0304 or 0x030c */
92 /* We cannot output two Unicode characters at once. So,
93 output the first character and buffer the second one. */
94 *pwc = wc1;
95 conv->istate = wc2;
96 return 2;
97 }
98 }
99 }
100 return RET_ILSEQ;
101 }
102 }
103
104 #define big5hkscs1999_flushwc normal_flushwc
105
106 static int
big5hkscs1999_wctomb(conv_t conv,unsigned char * r,ucs4_t wc,int n)107 big5hkscs1999_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n)
108 {
109 int count = 0;
110 unsigned char last = conv->ostate;
111
112 if (last) {
113 /* last is = 0x66 or = 0xa7. */
114 if (wc == 0x0304 || wc == 0x030c) {
115 /* Output the combined character. */
116 if (n >= 2) {
117 r[0] = 0x88;
118 r[1] = last + ((wc & 24) >> 2) - 4; /* = 0x62 or 0x64 or 0xa3 or 0xa5 */
119 conv->ostate = 0;
120 return 2;
121 } else
122 return RET_TOOSMALL;
123 }
124
125 /* Output the buffered character. */
126 if (n < 2)
127 return RET_TOOSMALL;
128 r[0] = 0x88;
129 r[1] = last;
130 r += 2;
131 count = 2;
132 }
133
134 /* Code set 0 (ASCII) */
135 if (wc < 0x0080) {
136 /* Plain ASCII character. */
137 if (n > count) {
138 r[0] = (unsigned char) wc;
139 conv->ostate = 0;
140 return count+1;
141 } else
142 return RET_TOOSMALL;
143 } else {
144 unsigned char buf[2];
145 int ret;
146
147 /* Code set 1 (BIG5 extended) */
148 ret = big5_wctomb(conv,buf,wc,2);
149 if (ret != RET_ILUNI) {
150 if (ret != 2) abort();
151 if (!((buf[0] == 0xc6 && buf[1] >= 0xa1) || buf[0] == 0xc7)) {
152 if (n >= count+2) {
153 r[0] = buf[0];
154 r[1] = buf[1];
155 conv->ostate = 0;
156 return count+2;
157 } else
158 return RET_TOOSMALL;
159 }
160 }
161 ret = hkscs1999_wctomb(conv,buf,wc,2);
162 if (ret != RET_ILUNI) {
163 if (ret != 2) abort();
164 if ((wc & ~0x0020) == 0x00ca) {
165 /* A possible first character of a multi-character sequence. We have to
166 buffer it. */
167 if (!(buf[0] == 0x88 && (buf[1] == 0x66 || buf[1] == 0xa7))) abort();
168 conv->ostate = buf[1]; /* = 0x66 or = 0xa7 */
169 return count+0;
170 }
171 if (n >= count+2) {
172 r[0] = buf[0];
173 r[1] = buf[1];
174 conv->ostate = 0;
175 return count+2;
176 } else
177 return RET_TOOSMALL;
178 }
179 return RET_ILUNI;
180 }
181 }
182
183 static int
big5hkscs1999_reset(conv_t conv,unsigned char * r,int n)184 big5hkscs1999_reset (conv_t conv, unsigned char *r, int n)
185 {
186 unsigned char last = conv->ostate;
187
188 if (last) {
189 if (n < 2)
190 return RET_TOOSMALL;
191 r[0] = 0x88;
192 r[1] = last;
193 /* conv->ostate = 0; will be done by the caller */
194 return 2;
195 } else
196 return 0;
197 }
198