/* * iso2022common.h: Common Codec Routines for ISO-2022 codecs. * * Written by Hye-Shik Chang * $CJKCodecs: iso2022common.h,v 1.8 2003/12/31 05:46:55 perky Exp $ */ /* This ISO-2022 implementation is intended to comply ECMA-43 Level 1 * rather than RFCs itself */ #define ESC 0x1b #define SO 0x0e #define SI 0x0f #define MAX_ESCSEQLEN 16 #define IS_ESCEND(c) (((c) >= 'A' && (c) <= 'Z') || (c) == '@') #define IS_ISO2022ESC(c2) ((c2) == '(' || (c2) == ')' || (c2) == '$' || \ (c2) == '.' || (c2) == '&') /* this is not a full list of ISO-2022 escape sequence headers. * but, it's enough to implement CJK instances of iso-2022. */ /* STATE state->c[0-3] 00000000 ||^^^^^| |+-----+---- G0-3 Character Set +----------- Is G0-3 double byte? state->c[4] 00000000 || |+---- Locked-Shift? +----- ESC Throughout */ #define CHARSET_DOUBLEBYTE 0x80 #define CHARSET_ASCII 'B' #define CHARSET_ISO8859_1 'A' #define CHARSET_ISO8859_7 'F' #define CHARSET_KSX1001 ('C'|CHARSET_DOUBLEBYTE) #define CHARSET_JISX0201_R 'J' #define CHARSET_JISX0201_K 'I' #define CHARSET_JISX0208 ('B'|CHARSET_DOUBLEBYTE) #define CHARSET_JISX0208_O ('@'|CHARSET_DOUBLEBYTE) #define CHARSET_JISX0212 ('D'|CHARSET_DOUBLEBYTE) #define CHARSET_JISX0213_1 ('O'|CHARSET_DOUBLEBYTE) #define CHARSET_JISX0213_2 ('P'|CHARSET_DOUBLEBYTE) #define CHARSET_GB2312 ('A'|CHARSET_DOUBLEBYTE) #define CHARSET_GB2312_8565 ('E'|CHARSET_DOUBLEBYTE) #define CHARSET_DESIGN(c) ((c) & 0x7f) #define CHARSET_ISDBCS(c) ((c) & 0x80) #define F_SHIFTED 0x01 #define F_ESCTHROUGHOUT 0x02 #define STATE_SETG(dn, s, v) ((s)->c[dn]) = (v); #define STATE_GETG(dn, s) ((s)->c[dn]) #define STATE_SETG0(s, v) STATE_SETG(0, s, v) #define STATE_GETG0(s) STATE_GETG(0, s) #define STATE_SETG1(s, v) STATE_SETG(1, s, v) #define STATE_GETG1(s) STATE_GETG(1, s) #define STATE_SETG2(s, v) STATE_SETG(2, s, v) #define STATE_GETG2(s) STATE_GETG(2, s) #define STATE_SETG3(s, v) STATE_SETG(3, s, v) #define STATE_GETG3(s) STATE_GETG(3, s) #define STATE_SETFLAG(s, f) ((s)->c[4]) |= (f); #define STATE_GETFLAG(s, f) ((s)->c[4] & (f)) #define STATE_CLEARFLAG(s, f) ((s)->c[4]) &= ~(f); #define STATE_CLEARFLAGS(s) ((s)->c[4]) = 0; #define ISO2022_GETCHARSET(charset, c1) \ if ((c) >= 0x80) \ return 1; \ if (STATE_GETFLAG(state, F_SHIFTED)) /* G1 */ \ (charset) = STATE_GETG1(state); \ else /* G1 */ \ (charset) = STATE_GETG0(state); \ #ifdef ISO2022_USE_G2_DESIGNATION /* hardcoded for iso-2022-jp-2 for now. we'll need to generalize it when we have more G2 designating encodings */ #define SS2_ROUTINE \ if (IN2 == 'N') { /* SS2 */ \ RESERVE_INBUF(3) \ if (STATE_GETG2(state) == CHARSET_ISO8859_1) { \ ISO8859_1_DECODE(IN3 ^ 0x80, **outbuf) \ else return 3; \ } else if (STATE_GETG2(state) == CHARSET_ISO8859_7) { \ ISO8859_7_DECODE(IN3 ^ 0x80, **outbuf) \ else return 3; \ } else if (STATE_GETG2(state) == CHARSET_ASCII) { \ if (IN3 & 0x80) return 3; \ else **outbuf = IN3; \ } else \ return MBERR_INTERNAL; \ NEXT(3, 1) \ } else #else #define SS2_ROUTINE #endif #ifndef ISO2022_NO_SHIFT #define SHIFT_CASES \ case SI: \ STATE_CLEARFLAG(state, F_SHIFTED) \ NEXT_IN(1) \ break; \ case SO: \ STATE_SETFLAG(state, F_SHIFTED) \ NEXT_IN(1) \ break; #else /* for compatibility with JapaneseCodecs */ #define SHIFT_CASES #endif #define ISO2022_BASECASES(c1) \ case ESC: \ RESERVE_INBUF(2) \ if (IS_ISO2022ESC(IN2)) { \ int err; \ err = iso2022processesc(state, inbuf, &inleft); \ if (err != 0) \ return err; \ } else SS2_ROUTINE { \ STATE_SETFLAG(state, F_ESCTHROUGHOUT) \ OUT1(ESC) \ NEXT(1, 1) \ } \ break; \ SHIFT_CASES \ case '\n': \ STATE_CLEARFLAG(state, F_SHIFTED) \ WRITE1('\n') \ NEXT(1, 1) \ break; #define ISO2022_ESCTHROUGHOUT(c) \ if (STATE_GETFLAG(state, F_ESCTHROUGHOUT)) { \ /* ESC throughout mode: for non-iso2022 escape sequences */ \ RESERVE_OUTBUF(1) \ OUT1(c) /* assume as ISO-8859-1 */ \ NEXT(1, 1) \ if (IS_ESCEND(c)) { \ STATE_CLEARFLAG(state, F_ESCTHROUGHOUT) \ } \ continue; \ } #define ISO2022_LOOP_BEGIN \ while (inleft > 0) { \ unsigned char c = IN1; \ ISO2022_ESCTHROUGHOUT(c) \ switch(c) { \ ISO2022_BASECASES(c) \ default: \ if (c < 0x20) { /* C0 */ \ RESERVE_OUTBUF(1) \ OUT1(c) \ NEXT(1, 1) \ } else if (c >= 0x80) \ return 1; \ else { #define ISO2022_LOOP_END \ } \ } \ } static int iso2022processesc(MultibyteCodec_State *state, const unsigned char **inbuf, size_t *inleft) { unsigned char charset, designation; size_t i, esclen; for (i = 1;i < MAX_ESCSEQLEN;i++) { if (i >= *inleft) return MBERR_TOOFEW; if (IS_ESCEND((*inbuf)[i])) { esclen = i + 1; break; } #ifdef ISO2022_USE_JISX0208EXT else if (i+1 < *inleft && (*inbuf)[i] == '&' && (*inbuf)[i+1] == '@') i += 2; #endif } if (i >= MAX_ESCSEQLEN) return 1; /* unterminated escape sequence */ switch (esclen) { case 3: if (IN2 == '$') { charset = IN3 | CHARSET_DOUBLEBYTE; designation = 0; } else { charset = IN3; if (IN2 == '(') designation = 0; else if (IN2 == ')') designation = 1; #ifdef ISO2022_USE_G2_DESIGNATION else if (IN2 == '.') designation = 2; #endif else return 3; } break; case 4: if (IN2 != '$') return 4; charset = IN4 | CHARSET_DOUBLEBYTE; if (IN3 == '(') designation = 0; else if (IN3 == ')') designation = 1; else return 4; break; #ifdef ISO2022_USE_JISX0208EXT case 6: /* designation with prefix */ if ((*inbuf)[3] == ESC && (*inbuf)[4] == '$' && (*inbuf)[5] == 'B') { charset = 'B' | CHARSET_DOUBLEBYTE; designation = 0; } else return 6; break; #endif default: return esclen; } { /* raise error when the charset is not designated for this encoding */ const unsigned char dsgs[] = {ISO2022_DESIGNATIONS, '\x00'}; for (i = 0; dsgs[i] != '\x00'; i++) if (dsgs[i] == charset) break; if (dsgs[i] == '\x00') return esclen; } STATE_SETG(designation, state, charset) *inleft -= esclen; (*inbuf) += esclen; return 0; }