/*
* Copyright (C) 2005 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.
*/
/*
* CP936
*/
/*
* The IANA has CP936 as an alias of GBK. But GBK is an official Chinese
* specification, whereas CP936 is de-facto maintained by Microsoft. And,
* of course, Microsoft modified CP936 since 1999.
*
* The differences from GBK are:
*
* 1. A single character:
*
* code CP936.TXT
* 0x80 0x20AC # EURO SIGN
*
* Some variants of CP936 (in JDK, Windows-2000, ICU) also add:
*
* 2. Private area mappings:
*
* code Unicode
* 0x{A1..A2}{40..7E,80..A0} U+E4C6..U+E585
* 0x{AA..AF,F8..FE}{A1..FE} U+E000..U+E4C5
*
* We add them too because, although there are backward compatibility problems
* when a character from a private area is moved to an official Unicode code
* point, they are useful for some people in practice.
*/
static int
cp936_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n)
{
/* Try GBK first. */
{
int ret = ces_gbk_mbtowc(conv,pwc,s,n);
if (ret != RET_ILSEQ)
return ret;
}
/* Then handle the additional mappings. */
{
unsigned char c = *s;
if (c == 0x80) {
*pwc = 0x20ac;
return 1;
}
/* User-defined characters */
if (c >= 0xa1 && c <= 0xa2) {
if (n < 2)
return RET_TOOFEW(0);
{
unsigned char c2 = s[1];
if ((c2 >= 0x40 && c2 < 0x7f) || (c2 >= 0x80 && c2 < 0xa1)) {
*pwc = 0xe4c6 + 96 * (c - 0xa1) + (c2 - (c2 >= 0x80 ? 0x41 : 0x40));
return 2;
}
}
} else if ((c >= 0xaa && c < 0xb0) || (c >= 0xf8 && c < 0xff)) {
if (n < 2)
return RET_TOOFEW(0);
{
unsigned char c2 = s[1];
if (c2 >= 0xa1 && c2 < 0xff) {
*pwc = 0xe000 + 94 * (c - (c >= 0xf8 ? 0xf2 : 0xaa)) + (c2 - 0xa1);
return 2;
}
}
}
}
return RET_ILSEQ;
}
static int
cp936_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n)
{
/* Try GBK first. */
{
int ret = ces_gbk_wctomb(conv,r,wc,n);
if (ret != RET_ILUNI)
return ret;
}
/* Then handle the additional mappings. */
if (wc >= 0xe000 && wc < 0xe586) {
/* User-defined characters */
if (n < 2)
return RET_TOOFEW(0);
if (wc < 0xe4c6) {
unsigned int i = wc - 0xe000;
unsigned int c1 = i / 94;
unsigned int c2 = i % 94;
r[0] = c1 + (c1 < 6 ? 0xaa : 0xf2);
r[1] = c2 + 0xa1;
return 2;
} else {
unsigned int i = wc - 0xe4c6;
unsigned int c1 = i / 96;
unsigned int c2 = i % 96;
r[0] = c1 + 0xa1;
r[1] = c2 + (c2 < 0x3f ? 0x40 : 0x41);
return 2;
}
} else if (wc == 0x20ac) {
r[0] = 0x80;
return 1;
}
return RET_ILUNI;
}
