wine/unicode/wctomb.c
2000-06-13 04:34:41 +00:00

213 lines
7.6 KiB
C

/*
* WideCharToMultiByte implementation
*
* Copyright 2000 Alexandre Julliard
*/
#include <string.h>
#include "winnls.h"
#include "wine/unicode.h"
/* wcstombs for single-byte code page */
static inline int wcstombs_sbcs( const struct sbcs_table *table,
const WCHAR *src, unsigned int srclen,
char *dst, unsigned int dstlen )
{
const unsigned char * const uni2cp_low = table->uni2cp_low;
const unsigned short * const uni2cp_high = table->uni2cp_high;
int ret = srclen;
if (dstlen < srclen)
{
/* buffer too small: fill it up to dstlen and return error */
srclen = dstlen;
ret = -1;
}
for (;;)
{
switch(srclen)
{
default:
case 16: dst[15] = uni2cp_low[uni2cp_high[src[15] >> 8] + (src[15] & 0xff)];
case 15: dst[14] = uni2cp_low[uni2cp_high[src[14] >> 8] + (src[14] & 0xff)];
case 14: dst[13] = uni2cp_low[uni2cp_high[src[13] >> 8] + (src[13] & 0xff)];
case 13: dst[12] = uni2cp_low[uni2cp_high[src[12] >> 8] + (src[12] & 0xff)];
case 12: dst[11] = uni2cp_low[uni2cp_high[src[11] >> 8] + (src[11] & 0xff)];
case 11: dst[10] = uni2cp_low[uni2cp_high[src[10] >> 8] + (src[10] & 0xff)];
case 10: dst[9] = uni2cp_low[uni2cp_high[src[9] >> 8] + (src[9] & 0xff)];
case 9: dst[8] = uni2cp_low[uni2cp_high[src[8] >> 8] + (src[8] & 0xff)];
case 8: dst[7] = uni2cp_low[uni2cp_high[src[7] >> 8] + (src[7] & 0xff)];
case 7: dst[6] = uni2cp_low[uni2cp_high[src[6] >> 8] + (src[6] & 0xff)];
case 6: dst[5] = uni2cp_low[uni2cp_high[src[5] >> 8] + (src[5] & 0xff)];
case 5: dst[4] = uni2cp_low[uni2cp_high[src[4] >> 8] + (src[4] & 0xff)];
case 4: dst[3] = uni2cp_low[uni2cp_high[src[3] >> 8] + (src[3] & 0xff)];
case 3: dst[2] = uni2cp_low[uni2cp_high[src[2] >> 8] + (src[2] & 0xff)];
case 2: dst[1] = uni2cp_low[uni2cp_high[src[1] >> 8] + (src[1] & 0xff)];
case 1: dst[0] = uni2cp_low[uni2cp_high[src[0] >> 8] + (src[0] & 0xff)];
case 0: break;
}
if (srclen < 16) return ret;
dst += 16;
src += 16;
srclen -= 16;
}
}
/* slow version of wcstombs_sbcs that handles the various flags */
static int wcstombs_sbcs_slow( const struct sbcs_table *table, int flags,
const WCHAR *src, unsigned int srclen,
char *dst, unsigned int dstlen,
const char *defchar, int *used )
{
const WCHAR * const cp2uni = table->cp2uni;
const unsigned char * const uni2cp_low = table->uni2cp_low;
const unsigned short * const uni2cp_high = table->uni2cp_high;
const unsigned char table_default = table->info.def_char & 0xff;
int ret = srclen, tmp;
if (dstlen < srclen)
{
/* buffer too small: fill it up to dstlen and return error */
srclen = dstlen;
ret = -1;
}
if (!defchar) defchar = &table_default;
if (!used) used = &tmp; /* avoid checking on every char */
while (srclen)
{
unsigned char ch = uni2cp_low[uni2cp_high[*src >> 8] + (*src & 0xff)];
if (((flags & WC_NO_BEST_FIT_CHARS) && (cp2uni[ch] != *src)) ||
(ch == table_default && *src != table->info.def_unicode_char))
{
ch = *defchar;
*used = 1;
}
*dst++ = ch;
src++;
srclen--;
}
return ret;
}
/* query necessary dst length for src string */
static inline int get_length_dbcs( const struct dbcs_table *table,
const WCHAR *src, unsigned int srclen )
{
const unsigned short * const uni2cp_low = table->uni2cp_low;
const unsigned short * const uni2cp_high = table->uni2cp_high;
int len;
for (len = 0; srclen; srclen--, src++, len++)
{
if (uni2cp_low[uni2cp_high[*src >> 8] + (*src & 0xff)] & 0xff00) len++;
}
return len;
}
/* wcstombs for double-byte code page */
static inline int wcstombs_dbcs( const struct dbcs_table *table,
const WCHAR *src, unsigned int srclen,
char *dst, unsigned int dstlen )
{
const unsigned short * const uni2cp_low = table->uni2cp_low;
const unsigned short * const uni2cp_high = table->uni2cp_high;
int len;
for (len = dstlen; srclen && len; len--, srclen--, src++)
{
unsigned short res = uni2cp_low[uni2cp_high[*src >> 8] + (*src & 0xff)];
if (res & 0xff00)
{
if (len == 1) break; /* do not output a partial char */
len--;
*dst++ = res >> 8;
}
*dst++ = (char)res;
}
if (srclen) return -1; /* overflow */
return dstlen - len;
}
/* slow version of wcstombs_dbcs that handles the various flags */
static int wcstombs_dbcs_slow( const struct dbcs_table *table, int flags,
const WCHAR *src, unsigned int srclen,
char *dst, unsigned int dstlen,
const char *defchar, int *used )
{
const WCHAR * const cp2uni = table->cp2uni;
const unsigned short * const uni2cp_low = table->uni2cp_low;
const unsigned short * const uni2cp_high = table->uni2cp_high;
const unsigned char * const cp2uni_lb = table->cp2uni_leadbytes;
WCHAR defchar_value = table->info.def_char;
int len, tmp;
if (defchar) defchar_value = defchar[1] ? ((defchar[0] << 8) | defchar[1]) : defchar[0];
if (!used) used = &tmp; /* avoid checking on every char */
for (len = dstlen; srclen && len; len--, srclen--, src++)
{
unsigned short res = uni2cp_low[uni2cp_high[*src >> 8] + (*src & 0xff)];
if (res == table->info.def_char && *src != table->info.def_unicode_char)
{
res = defchar_value;
*used = 1;
}
else if (flags & WC_NO_BEST_FIT_CHARS)
{
/* check if char maps back to the same Unicode value */
if (res & 0xff00)
{
unsigned char off = cp2uni_lb[res >> 8];
if (cp2uni[(off << 8) + (res & 0xff)] != *src)
{
res = defchar_value;
*used = 1;
}
}
else if (cp2uni[res & 0xff] != *src)
{
res = defchar_value;
*used = 1;
}
}
if (res & 0xff00)
{
if (len == 1) break; /* do not output a partial char */
len--;
*dst++ = res >> 8;
}
*dst++ = (char)res;
}
if (srclen) return -1; /* overflow */
return dstlen - len;
}
/* wide char to multi byte string conversion */
/* return -1 on dst buffer overflow */
int cp_wcstombs( const union cptable *table, int flags,
const WCHAR *src, int srclen,
char *dst, int dstlen, const char *defchar, int *used )
{
if (table->info.char_size == 1)
{
if (!dstlen) return srclen;
if (flags || defchar || used)
return wcstombs_sbcs_slow( &table->sbcs, flags, src, srclen,
dst, dstlen, defchar, used );
return wcstombs_sbcs( &table->sbcs, src, srclen, dst, dstlen );
}
else /* mbcs */
{
if (!dstlen) return get_length_dbcs( &table->dbcs, src, srclen );
if (flags || defchar || used)
return wcstombs_dbcs_slow( &table->dbcs, flags, src, srclen,
dst, dstlen, defchar, used );
return wcstombs_dbcs( &table->dbcs, src, srclen, dst, dstlen );
}
}