/*
* Copyright (C) 1999-2001 Free Software Foundation, Inc.
* This file is part of the GNU LIBICONV Library.
*
* The GNU LIBICONV Library is free software; you can redistribute it
* and/or modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* The GNU LIBICONV Library is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with the GNU LIBICONV Library; see the file COPYING.LIB.
* If not, write to the Free Software Foundation, Inc., 51 Franklin Street,
* Fifth Floor, Boston, MA 02110-1301, USA.
*/
/*
* JOHAB Hangul
*
* Ken Lunde writes in his "CJKV Information Processing" book, p. 114:
* "Hangul can be composed of two or three jamo (some jamo are considered
* compound). Johab uses 19 initial jamo (consonants), 21 medial jamo (vowels)
* and 27 final jamo (consonants; 28 when you include the "fill" character
* for Hangul containing only two jamo). Multiplying these numbers results in
* 11172."
*
* Structure of the Johab encoding (see p. 181-184):
* bit 15 = 1
* bit 14..10 = initial jamo, only 19+1 out of 32 possible values are used
* bit 9..5 = medial jamo, only 21+1 out of 32 possible values are used
* bit 4..0 = final jamo, only 27+1 out of 32 possible values are used
*
* Structure of the Unicode encoding:
* grep '^0x\([8-C]...\|D[0-7]..\)' unicode.org-mappings/EASTASIA/KSC/JOHAB.TXT
* You see that all characters there are marked "HANGUL LETTER" or "HANGUL
* SYLLABLE". If you eliminate the "HANGUL LETTER"s, the table is sorted
* in ascending order according to Johab encoding and according to the Unicode
* encoding. Now look a little more carefully, and you see that the following
* formula holds:
* unicode == 0xAC00
* + 21 * 28 * (jamo_initial_index[(johab >> 10) & 31] - 1)
* + 28 * (jamo_medial_index[(johab >> 5) & 31] - 1)
* + jamo_final_index[johab & 31]
* where the index tables are defined as below.
*/
/* Tables mapping 5-bit groups to jamo letters. */
/* Note that Jamo XX = UHC 0xA4A0+XX = Unicode 0x3130+XX */
#define NONE 0xfd
#define FILL 0xff
static const unsigned char jamo_initial[32] = {
NONE, FILL, 0x01, 0x02, 0x04, 0x07, 0x08, 0x09,
0x11, 0x12, 0x13, 0x15, 0x16, 0x17, 0x18, 0x19,
0x1a, 0x1b, 0x1c, 0x1d, 0x1e, NONE, NONE, NONE,
NONE, NONE, NONE, NONE, NONE, NONE, NONE, NONE,
};
static const unsigned char jamo_medial[32] = {
NONE, NONE, FILL, 0x1f, 0x20, 0x21, 0x22, 0x23,
NONE, NONE, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29,
NONE, NONE, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
NONE, NONE, 0x30, 0x31, 0x32, 0x33, NONE, NONE,
};
static const unsigned char jamo_final[32] = {
NONE, FILL, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
0x07, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x10, 0x11, NONE, 0x12, 0x14, 0x15, 0x16, 0x17,
0x18, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, NONE, NONE,
};
/* Same as jamo_final, except that it excludes characters already
contained in jamo_initial. 11 characters instead of 27. */
static const unsigned char jamo_final_notinitial[32] = {
NONE, NONE, NONE, NONE, 0x03, NONE, 0x05, 0x06,
NONE, NONE, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x10, NONE, NONE, NONE, 0x14, NONE, NONE, NONE,
NONE, NONE, NONE, NONE, NONE, NONE, NONE, NONE,
};
/* Tables mapping 5-bit groups to packed indices. */
#define none -1
#define fill 0
static const signed char jamo_initial_index[32] = {
none, fill, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e,
0x0f, 0x10, 0x11, 0x12, 0x13, none, none, none,
none, none, none, none, none, none, none, none,
};
static const signed char jamo_medial_index[32] = {
none, none, fill, 0x01, 0x02, 0x03, 0x04, 0x05,
none, none, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
none, none, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11,
none, none, 0x12, 0x13, 0x14, 0x15, none, none,
};
static const signed char jamo_final_index[32] = {
none, fill, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e,
0x0f, 0x10, none, 0x11, 0x12, 0x13, 0x14, 0x15,
0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, none, none,
};
static int
johab_hangul_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n)
{
unsigned char c1 = s[0];
if ((c1 >= 0x84 && c1 <= 0xd3)) {
if (n >= 2) {
unsigned char c2 = s[1];
if ((c2 >= 0x41 && c2 < 0x7f) || (c2 >= 0x81 && c2 < 0xff)) {
unsigned int johab = (c1 << 8) | c2;
unsigned int bitspart1 = (johab >> 10) & 31;
unsigned int bitspart2 = (johab >> 5) & 31;
unsigned int bitspart3 = johab & 31;
int index1 = jamo_initial_index[bitspart1];
int index2 = jamo_medial_index[bitspart2];
int index3 = jamo_final_index[bitspart3];
/* Exclude "none" values. */
if (index1 >= 0 && index2 >= 0 && index3 >= 0) {
/* Deal with "fill" values in initial or medial position. */
if (index1 == fill) {
if (index2 == fill) {
unsigned char jamo3 = jamo_final_notinitial[bitspart3];
if (jamo3 != NONE) {
*pwc = (ucs4_t) 0x3130 + jamo3;
return 2;
}
} else if (index3 == fill) {
unsigned char jamo2 = jamo_medial[bitspart2];
if (jamo2 != NONE && jamo2 != FILL) {
*pwc = (ucs4_t) 0x3130 + jamo2;
return 2;
}
}
/* Syllables composed only of medial and final don't exist. */
} else if (index2 == fill) {
if (index3 == fill) {
unsigned char jamo1 = jamo_initial[bitspart1];
if (jamo1 != NONE && jamo1 != FILL) {
*pwc = (ucs4_t) 0x3130 + jamo1;
return 2;
}
}
/* Syllables composed only of initial and final don't exist. */
} else {
/* index1 and index2 are not fill, but index3 may be fill. */
/* Nothing more to exclude. All 11172 code points are valid. */
*pwc = 0xac00 + ((index1 - 1) * 21 + (index2 - 1)) * 28 + index3;
return 2;
}
}
}
return RET_ILSEQ;
}
return RET_TOOFEW(0);
}
return RET_ILSEQ;
}
/* 51 Jamo: 19 initial, 21 medial, 11 final not initial. */
static const unsigned short johab_hangul_page31[51] = {
0x8841, 0x8c41, 0x8444, 0x9041, 0x8446, 0x8447, 0x9441, /*0x30-0x37*/
0x9841, 0x9c41, 0x844a, 0x844b, 0x844c, 0x844d, 0x844e, 0x844f, /*0x38-0x3f*/
0x8450, 0xa041, 0xa441, 0xa841, 0x8454, 0xac41, 0xb041, 0xb441, /*0x40-0x47*/
0xb841, 0xbc41, 0xc041, 0xc441, 0xc841, 0xcc41, 0xd041, 0x8461, /*0x48-0x4f*/
0x8481, 0x84a1, 0x84c1, 0x84e1, 0x8541, 0x8561, 0x8581, 0x85a1, /*0x50-0x57*/
0x85c1, 0x85e1, 0x8641, 0x8661, 0x8681, 0x86a1, 0x86c1, 0x86e1, /*0x58-0x5f*/
0x8741, 0x8761, 0x8781, 0x87a1, /*0x60-0x67*/
};
/* Tables mapping packed indices to 5-bit groups. */
/* index1+1 = jamo_initial_index[bitspart1] <==>
bitspart1 = jamo_initial_index_inverse[index1] */
static const char jamo_initial_index_inverse[19] = {
0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x10, 0x11, 0x12, 0x13, 0x14,
};
/* index2+1 = jamo_medial_index[bitspart2] <==>
bitspart2 = jamo_medial_index_inverse[index2] */
static const char jamo_medial_index_inverse[21] = {
0x03, 0x04, 0x05, 0x06, 0x07,
0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
0x1a, 0x1b, 0x1c, 0x1d,
};
/* index3 = jamo_final_index[bitspart3] <==>
bitspart3 = jamo_final_index_inverse[index3] */
static const char jamo_final_index_inverse[28] = {
0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x10, 0x11, 0x13, 0x14, 0x15, 0x16, 0x17,
0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d,
};
static int
johab_hangul_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n)
{
if (n >= 2) {
if (wc >= 0x3131 && wc < 0x3164) {
unsigned short c = johab_hangul_page31[wc-0x3131];
r[0] = (c >> 8); r[1] = (c & 0xff);
return 2;
} else if (wc >= 0xac00 && wc < 0xd7a4) {
unsigned int index1;
unsigned int index2;
unsigned int index3;
unsigned short c;
unsigned int tmp = wc - 0xac00;
index3 = tmp % 28; tmp = tmp / 28;
index2 = tmp % 21; tmp = tmp / 21;
index1 = tmp;
c = (((((1 << 5)
| jamo_initial_index_inverse[index1]) << 5)
| jamo_medial_index_inverse[index2]) << 5)
| jamo_final_index_inverse[index3];
r[0] = (c >> 8); r[1] = (c & 0xff);
return 2;
}
return RET_ILUNI;
}
return RET_TOOSMALL;
}
/*
* Decomposition of JOHAB Hangul in one to three Johab Jamo elements.
*/
/* Decompose wc into r[0..2], and return the number of resulting Jamo elements.
Return RET_ILUNI if decomposition is not possible. */
static int johab_hangul_decompose (conv_t conv, ucs4_t* r, ucs4_t wc)
{
unsigned char buf[2];
int ret = johab_hangul_wctomb(conv,buf,wc,2);
if (ret != RET_ILUNI) {
unsigned int hangul = (buf[0] << 8) | buf[1];
unsigned char jamo1 = jamo_initial[(hangul >> 10) & 31];
unsigned char jamo2 = jamo_medial[(hangul >> 5) & 31];
unsigned char jamo3 = jamo_final[hangul & 31];
if ((hangul >> 15) != 1) abort();
if (jamo1 != NONE && jamo2 != NONE && jamo3 != NONE) {
/* They are not all three == FILL because that would correspond to
johab = 0x8441, which doesn't exist. */
ucs4_t* p = r;
if (jamo1 != FILL)
*p++ = 0x3130 + jamo1;
if (jamo2 != FILL)
*p++ = 0x3130 + jamo2;
if (jamo3 != FILL)
*p++ = 0x3130 + jamo3;
return p-r;
}
}
return RET_ILUNI;
}
#undef fill
#undef none
#undef FILL
#undef NONE
