/*
* 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.
*/
/*
* ISO-2022-CN
*/
/* Specification: RFC 1922 */
#define ESC 0x1b
#define SO 0x0e
#define SI 0x0f
/*
* The state is composed of one of the following values
*/
#define STATE_ASCII 0
#define STATE_TWOBYTE 1
/*
* and one of the following values, << 8
*/
#define STATE2_NONE 0
#define STATE2_DESIGNATED_GB2312 1
#define STATE2_DESIGNATED_CNS11643_1 2
/*
* and one of the following values, << 16
*/
#define STATE3_NONE 0
#define STATE3_DESIGNATED_CNS11643_2 1
#define SPLIT_STATE \
unsigned int state1 = state & 0xff, state2 = (state >> 8) & 0xff, state3 = state >> 16
#define COMBINE_STATE \
state = (state3 << 16) | (state2 << 8) | state1
static int
iso2022_cn_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n)
{
state_t state = conv->istate;
SPLIT_STATE;
int count = 0;
unsigned char c;
for (;;) {
c = *s;
if (c == ESC) {
if (n < count+4)
goto none;
if (s[1] == '$') {
if (s[2] == ')') {
if (s[3] == 'A') {
state2 = STATE2_DESIGNATED_GB2312;
s += 4; count += 4;
if (n < count+1)
goto none;
continue;
}
if (s[3] == 'G') {
state2 = STATE2_DESIGNATED_CNS11643_1;
s += 4; count += 4;
if (n < count+1)
goto none;
continue;
}
}
if (s[2] == '*') {
if (s[3] == 'H') {
state3 = STATE3_DESIGNATED_CNS11643_2;
s += 4; count += 4;
if (n < count+1)
goto none;
continue;
}
}
}
if (s[1] == 'N') {
switch (state3) {
case STATE3_NONE:
return RET_ILSEQ;
case STATE3_DESIGNATED_CNS11643_2:
if (s[2] < 0x80 && s[3] < 0x80) {
int ret = cns11643_2_mbtowc(conv,pwc,s+2,2);
if (ret == RET_ILSEQ)
return RET_ILSEQ;
if (ret != 2) abort();
COMBINE_STATE;
conv->istate = state;
return count+4;
} else
return RET_ILSEQ;
default: abort();
}
}
return RET_ILSEQ;
}
if (c == SO) {
if (state2 != STATE2_DESIGNATED_GB2312 && state2 != STATE2_DESIGNATED_CNS11643_1)
return RET_ILSEQ;
state1 = STATE_TWOBYTE;
s++; count++;
if (n < count+1)
goto none;
continue;
}
if (c == SI) {
state1 = STATE_ASCII;
s++; count++;
if (n < count+1)
goto none;
continue;
}
break;
}
switch (state1) {
case STATE_ASCII:
if (c < 0x80) {
int ret = ascii_mbtowc(conv,pwc,s,1);
if (ret == RET_ILSEQ)
return RET_ILSEQ;
if (ret != 1) abort();
if (*pwc == 0x000a || *pwc == 0x000d) {
state2 = STATE2_NONE; state3 = STATE3_NONE;
}
COMBINE_STATE;
conv->istate = state;
return count+1;
} else
return RET_ILSEQ;
case STATE_TWOBYTE:
if (n < count+2)
goto none;
if (s[0] < 0x80 && s[1] < 0x80) {
int ret;
switch (state2) {
case STATE2_NONE:
return RET_ILSEQ;
case STATE2_DESIGNATED_GB2312:
ret = gb2312_mbtowc(conv,pwc,s,2); break;
case STATE2_DESIGNATED_CNS11643_1:
ret = cns11643_1_mbtowc(conv,pwc,s,2); break;
default: abort();
}
if (ret == RET_ILSEQ)
return RET_ILSEQ;
if (ret != 2) abort();
COMBINE_STATE;
conv->istate = state;
return count+2;
} else
return RET_ILSEQ;
default: abort();
}
none:
COMBINE_STATE;
conv->istate = state;
return RET_TOOFEW(count);
}
static int
iso2022_cn_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n)
{
state_t state = conv->ostate;
SPLIT_STATE;
unsigned char buf[3];
int ret;
/* There is no need to handle Unicode 3.1 tag characters and to look for
"zh-CN" or "zh-TW" tags, because GB2312 and CNS11643 are disjoint. */
/* Try ASCII. */
ret = ascii_wctomb(conv,buf,wc,1);
if (ret != RET_ILUNI) {
if (ret != 1) abort();
if (buf[0] < 0x80) {
int count = (state1 == STATE_ASCII ? 1 : 2);
if (n < count)
return RET_TOOSMALL;
if (state1 != STATE_ASCII) {
r[0] = SI;
r += 1;
state1 = STATE_ASCII;
}
r[0] = buf[0];
if (wc == 0x000a || wc == 0x000d) {
state2 = STATE2_NONE; state3 = STATE3_NONE;
}
COMBINE_STATE;
conv->ostate = state;
return count;
}
}
/* Try GB 2312-1980. */
ret = gb2312_wctomb(conv,buf,wc,2);
if (ret != RET_ILUNI) {
if (ret != 2) abort();
if (buf[0] < 0x80 && buf[1] < 0x80) {
int count = (state2 == STATE2_DESIGNATED_GB2312 ? 0 : 4) + (state1 == STATE_TWOBYTE ? 0 : 1) + 2;
if (n < count)
return RET_TOOSMALL;
if (state2 != STATE2_DESIGNATED_GB2312) {
r[0] = ESC;
r[1] = '$';
r[2] = ')';
r[3] = 'A';
r += 4;
state2 = STATE2_DESIGNATED_GB2312;
}
if (state1 != STATE_TWOBYTE) {
r[0] = SO;
r += 1;
state1 = STATE_TWOBYTE;
}
r[0] = buf[0];
r[1] = buf[1];
COMBINE_STATE;
conv->ostate = state;
return count;
}
}
ret = cns11643_wctomb(conv,buf,wc,3);
if (ret != RET_ILUNI) {
if (ret != 3) abort();
/* Try CNS 11643-1992 Plane 1. */
if (buf[0] == 1 && buf[1] < 0x80 && buf[2] < 0x80) {
int count = (state2 == STATE2_DESIGNATED_CNS11643_1 ? 0 : 4) + (state1 == STATE_TWOBYTE ? 0 : 1) + 2;
if (n < count)
return RET_TOOSMALL;
if (state2 != STATE2_DESIGNATED_CNS11643_1) {
r[0] = ESC;
r[1] = '$';
r[2] = ')';
r[3] = 'G';
r += 4;
state2 = STATE2_DESIGNATED_CNS11643_1;
}
if (state1 != STATE_TWOBYTE) {
r[0] = SO;
r += 1;
state1 = STATE_TWOBYTE;
}
r[0] = buf[1];
r[1] = buf[2];
COMBINE_STATE;
conv->ostate = state;
return count;
}
/* Try CNS 11643-1992 Plane 2. */
if (buf[0] == 2 && buf[1] < 0x80 && buf[2] < 0x80) {
int count = (state3 == STATE3_DESIGNATED_CNS11643_2 ? 0 : 4) + 4;
if (n < count)
return RET_TOOSMALL;
if (state3 != STATE3_DESIGNATED_CNS11643_2) {
r[0] = ESC;
r[1] = '$';
r[2] = '*';
r[3] = 'H';
r += 4;
state3 = STATE3_DESIGNATED_CNS11643_2;
}
r[0] = ESC;
r[1] = 'N';
r[2] = buf[1];
r[3] = buf[2];
COMBINE_STATE;
conv->ostate = state;
return count;
}
}
return RET_ILUNI;
}
static int
iso2022_cn_reset (conv_t conv, unsigned char *r, int n)
{
state_t state = conv->ostate;
SPLIT_STATE;
(void)state2;
(void)state3;
if (state1 != STATE_ASCII) {
if (n < 1)
return RET_TOOSMALL;
r[0] = SI;
/* conv->ostate = 0; will be done by the caller */
return 1;
} else
return 0;
}
#undef COMBINE_STATE
#undef SPLIT_STATE
#undef STATE3_DESIGNATED_CNS11643_2
#undef STATE3_NONE
#undef STATE2_DESIGNATED_CNS11643_1
#undef STATE2_DESIGNATED_GB2312
#undef STATE2_NONE
#undef STATE_TWOBYTE
#undef STATE_ASCII
