diff options
author | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2016-12-28 16:52:56 +0100 |
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committer | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2016-12-28 16:52:56 +0100 |
commit | 7b358424ebad9349421acd533c2fa1cbf6cf3e3e (patch) | |
tree | 686678532eefed525c242fd214d0cfb2914726c5 /app/tools/halibut/charset/euc.c |
Initial import of xtrkcad version 1:4.0.2-2
Diffstat (limited to 'app/tools/halibut/charset/euc.c')
-rw-r--r-- | app/tools/halibut/charset/euc.c | 272 |
1 files changed, 272 insertions, 0 deletions
diff --git a/app/tools/halibut/charset/euc.c b/app/tools/halibut/charset/euc.c new file mode 100644 index 0000000..b3d43ff --- /dev/null +++ b/app/tools/halibut/charset/euc.c @@ -0,0 +1,272 @@ +/* + * euc.c - routines to handle the various EUC multibyte encodings. + */ + +#ifndef ENUM_CHARSETS + +#include "charset.h" +#include "internal.h" + +struct euc { + int nchars[3]; /* GR, SS2+GR, SS3+GR */ + long int (*to_ucs)(unsigned long state); + unsigned long (*from_ucs)(long int ucs); +}; + +static void read_euc(charset_spec const *charset, long int input_chr, + charset_state *state, + void (*emit)(void *ctx, long int output), void *emitctx) +{ + struct euc const *euc = (struct euc *)charset->data; + + /* + * For EUC input, our state variable divides into three parts: + * + * - Topmost nibble (bits 31:28) is nonzero if we're + * accumulating a multibyte character, and it indicates + * which section we're in: 1 for GR chars, 2 for things + * beginning with SS2, 3 for things beginning with SS3. + * + * - Next nibble (bits 27:24) indicates how many bytes of the + * character we've accumulated so far. + * + * - The rest (bits 23:0) are those bytes in full, accumulated + * as a large integer (so that seeing A1 A2 A3, in a + * hypothetical EUC whose GR encoding is three-byte, runs + * our state variable from 0 -> 0x110000A1 -> 0x1200A1A2 -> + * 0x13A1A2A3, at which point it gets translated and output + * and resets to zero). + */ + + if (state->s0 != 0) { + + /* + * At this point, no matter whether we had an SS2 or SS3 + * introducer or not, we _always_ expect a GR character. + * Anything else causes us to emit ERROR for an incomplete + * character, and then reset to state 0 to process the + * character in its own way. + */ + if (input_chr < 0xA1 || input_chr == 0xFF) { + emit(emitctx, ERROR); + state->s0 = 0; + } else + state->s0 = (((state->s0 & 0xFF000000) + 0x01000000) | + ((state->s0 & 0x0000FFFF) << 8) | input_chr); + + } + + if (state->s0 == 0) { + /* + * The input character determines which of the four + * possible charsets we're going to be in. + */ + if (input_chr < 0x80) { /* this is always ASCII */ + emit(emitctx, input_chr); + } else if (input_chr == 0x8E) {/* SS2 means charset 2 */ + state->s0 = 0x20000000; + } else if (input_chr == 0x8F) {/* SS3 means charset 3 */ + state->s0 = 0x30000000; + } else if (input_chr < 0xA1 || input_chr == 0xFF) { /* errors */ + emit(emitctx, ERROR); + } else { /* A1-FE means charset 1 */ + state->s0 = 0x11000000 | input_chr; + } + } + + /* + * Finally, if we have accumulated a complete character, output + * it. + */ + if (state->s0 != 0 && + ((state->s0 & 0x0F000000) >> 24) >= + (unsigned)euc->nchars[(state->s0 >> 28)-1]) { + emit(emitctx, euc->to_ucs(state->s0)); + state->s0 = 0; + } +} + +/* + * All EUCs are stateless multi-byte encodings (in the sense that + * just after any character has been completed, the state is always + * the same); hence when writing them, there is no need to use the + * charset_state. + */ + +static int write_euc(charset_spec const *charset, long int input_chr, + charset_state *state, + void (*emit)(void *ctx, long int output), void *emitctx) +{ + struct euc const *euc = (struct euc *)charset->data; + unsigned long c; + int cset, len; + + UNUSEDARG(state); + + if (input_chr == -1) + return TRUE; /* stateless; no cleanup required */ + + /* ASCII is the easy bit, and is always the same. */ + if (input_chr < 0x80) { + emit(emitctx, input_chr); + return TRUE; + } + + c = euc->from_ucs(input_chr); + if (!c) { + return FALSE; + } + + cset = c >> 28; + len = euc->nchars[cset-1]; + c &= 0xFFFFFF; + + if (cset > 1) + emit(emitctx, 0x8C + cset); /* SS2/SS3 */ + + while (len--) + emit(emitctx, (c >> (8*len)) & 0xFF); + return TRUE; +} + +/* + * EUC-CN encodes GB2312 only. + */ +static long int euc_cn_to_ucs(unsigned long state) +{ + switch (state >> 28) { + case 1: return gb2312_to_unicode(((state >> 8) & 0xFF) - 0xA1, + ((state ) & 0xFF) - 0xA1); + default: return ERROR; + } +} +static unsigned long euc_cn_from_ucs(long int ucs) +{ + int r, c; + if (unicode_to_gb2312(ucs, &r, &c)) + return 0x10000000 | ((r+0xA1) << 8) | (c+0xA1); + else + return 0; +} +static const struct euc euc_cn = { + {2,0,0}, euc_cn_to_ucs, euc_cn_from_ucs +}; +const charset_spec charset_CS_EUC_CN = { + CS_EUC_CN, read_euc, write_euc, &euc_cn +}; + +/* + * EUC-KR encodes KS X 1001 only. + */ +static long int euc_kr_to_ucs(unsigned long state) +{ + switch (state >> 28) { + case 1: return ksx1001_to_unicode(((state >> 8) & 0xFF) - 0xA1, + ((state ) & 0xFF) - 0xA1); + default: return ERROR; + } +} +static unsigned long euc_kr_from_ucs(long int ucs) +{ + int r, c; + if (unicode_to_ksx1001(ucs, &r, &c)) + return 0x10000000 | ((r+0xA1) << 8) | (c+0xA1); + else + return 0; +} +static const struct euc euc_kr = { + {2,0,0}, euc_kr_to_ucs, euc_kr_from_ucs +}; +const charset_spec charset_CS_EUC_KR = { + CS_EUC_KR, read_euc, write_euc, &euc_kr +}; + +/* + * EUC-JP encodes several character sets. + */ +static long int euc_jp_to_ucs(unsigned long state) +{ + switch (state >> 28) { + case 1: return jisx0208_to_unicode(((state >> 8) & 0xFF) - 0xA1, + ((state ) & 0xFF) - 0xA1); + case 2: + /* + * This is the top half of JIS X 0201. That means A1-DF map + * to FF61-FF9F, and nothing else is valid. + */ + { + int c = state & 0xFF; + if (c >= 0xA1 && c <= 0xDF) + return c + (0xFF61 - 0xA1); + else + return ERROR; + } + /* (no break needed since all control paths have returned) */ + case 3: return jisx0212_to_unicode(((state >> 8) & 0xFF) - 0xA1, + ((state ) & 0xFF) - 0xA1); + default: return ERROR; /* placate optimisers */ + } +} +static unsigned long euc_jp_from_ucs(long int ucs) +{ + int r, c; + if (ucs >= 0xFF61 && ucs <= 0xFF9F) + return 0x20000000 | (ucs - (0xFF61 - 0xA1)); + else if (unicode_to_jisx0208(ucs, &r, &c)) + return 0x10000000 | ((r+0xA1) << 8) | (c+0xA1); + else if (unicode_to_jisx0212(ucs, &r, &c)) + return 0x30000000 | ((r+0xA1) << 8) | (c+0xA1); + else + return 0; +} +static const struct euc euc_jp = { + {2,1,2}, euc_jp_to_ucs, euc_jp_from_ucs +}; +const charset_spec charset_CS_EUC_JP = { + CS_EUC_JP, read_euc, write_euc, &euc_jp +}; + +/* + * EUC-TW encodes CNS 11643 (all planes). + */ +static long int euc_tw_to_ucs(unsigned long state) +{ + int plane; + switch (state >> 28) { + case 1: return cns11643_to_unicode(0, ((state >> 8) & 0xFF) - 0xA1, + ((state ) & 0xFF) - 0xA1); + case 2: + plane = ((state >> 8) & 0xFF) - 0xA1; + if (plane >= 7) return ERROR; + return cns11643_to_unicode(plane, ((state >> 8) & 0xFF) - 0xA1, + ((state ) & 0xFF) - 0xA1); + default: return ERROR; + } +} +static unsigned long euc_tw_from_ucs(long int ucs) +{ + int p, r, c; + if (unicode_to_cns11643(ucs, &p, &r, &c)) { + if (p == 0) + return 0x10000000 | ((r+0xA1) << 8) | (c+0xA1); + else + return 0x20000000 | + ((p + 0xA1) << 16) | ((r+0xA1) << 8) | (c+0xA1); + } else + return 0; +} +static const struct euc euc_tw = { + {2,3,0}, euc_tw_to_ucs, euc_tw_from_ucs +}; +const charset_spec charset_CS_EUC_TW = { + CS_EUC_TW, read_euc, write_euc, &euc_tw +}; + +#else /* ENUM_CHARSETS */ + +ENUM_CHARSET(CS_EUC_CN) +ENUM_CHARSET(CS_EUC_KR) +ENUM_CHARSET(CS_EUC_JP) +ENUM_CHARSET(CS_EUC_TW) + +#endif /* ENUM_CHARSETS */ |