wine/unicode/wctomb.c
2000-12-29 03:56:06 +00:00

400 lines
14 KiB
C

/*
* WideCharToMultiByte implementation
*
* Copyright 2000 Alexandre Julliard
*/
#include <string.h>
#include "winnls.h"
#include "wine/unicode.h"
/* search for a character in the unicode_compose_table; helper for compose() */
static inline int binary_search( WCHAR ch, int low, int high )
{
extern const WCHAR unicode_compose_table[];
while (low <= high)
{
int pos = (low + high) / 2;
if (unicode_compose_table[2*pos] < ch)
{
low = pos + 1;
continue;
}
if (unicode_compose_table[2*pos] > ch)
{
high = pos - 1;
continue;
}
return pos;
}
return -1;
}
/* return the result of the composition of two Unicode chars, or 0 if none */
static WCHAR compose( const WCHAR *str )
{
extern const WCHAR unicode_compose_table[];
extern const unsigned int unicode_compose_table_size;
int idx = 1, low = 0, high = unicode_compose_table_size - 1;
for (;;)
{
int pos = binary_search( str[idx], low, high );
if (pos == -1) return 0;
if (!idx--) return unicode_compose_table[2*pos+1];
low = unicode_compose_table[2*pos+1];
high = unicode_compose_table[2*pos+3] - 1;
}
}
/****************************************************************/
/* sbcs support */
/* check if 'ch' is an acceptable sbcs mapping for 'wch' */
static inline int is_valid_sbcs_mapping( const struct sbcs_table *table, int flags,
WCHAR wch, unsigned char ch )
{
if (flags & WC_NO_BEST_FIT_CHARS) return (table->cp2uni[ch] == wch);
if (ch != (unsigned char)table->info.def_char) return 1;
return (wch == table->info.def_unicode_char);
}
/* query necessary dst length for src string */
static inline int get_length_sbcs( const struct sbcs_table *table, int flags,
const WCHAR *src, unsigned int srclen )
{
unsigned int ret = srclen;
if (flags & WC_COMPOSITECHECK)
{
const unsigned char * const uni2cp_low = table->uni2cp_low;
const unsigned short * const uni2cp_high = table->uni2cp_high;
WCHAR composed;
for (ret = 0; srclen > 1; ret++, srclen--, src++)
{
if (!(composed = compose(src))) continue;
/* check if we should skip the next char */
/* in WC_DEFAULTCHAR and WC_DISCARDNS mode, we always skip */
/* the next char no matter if the composition is valid or not */
if (!(flags & (WC_DEFAULTCHAR|WC_DISCARDNS)))
{
unsigned char ch = uni2cp_low[uni2cp_high[composed >> 8] + (composed & 0xff)];
if (!is_valid_sbcs_mapping( table, flags, composed, ch )) continue;
}
src++;
srclen--;
}
if (srclen) ret++; /* last char */
}
return ret;
}
/* 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 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;
unsigned int len;
int tmp;
WCHAR composed;
if (!defchar) defchar = &table_default;
if (!used) used = &tmp; /* avoid checking on every char */
for (len = dstlen; srclen && len; dst++, len--, src++, srclen--)
{
WCHAR wch = *src;
if ((flags & WC_COMPOSITECHECK) && (srclen > 1) && (composed = compose(src)))
{
/* now check if we can use the composed char */
*dst = uni2cp_low[uni2cp_high[composed >> 8] + (composed & 0xff)];
if (is_valid_sbcs_mapping( table, flags, composed, *dst ))
{
/* we have a good mapping, use it */
src++;
srclen--;
continue;
}
/* no mapping for the composed char, check the other flags */
if (flags & WC_DEFAULTCHAR) /* use the default char instead */
{
*dst = *defchar;
*used = 1;
src++; /* skip the non-spacing char */
srclen--;
continue;
}
if (flags & WC_DISCARDNS) /* skip the second char of the composition */
{
src++;
srclen--;
}
/* WC_SEPCHARS is the default */
}
*dst = uni2cp_low[uni2cp_high[wch >> 8] + (wch & 0xff)];
if (!is_valid_sbcs_mapping( table, flags, wch, *dst ))
{
*dst = *defchar;
*used = 1;
}
}
if (srclen) return -1; /* overflow */
return dstlen - len;
}
/****************************************************************/
/* dbcs support */
/* check if 'ch' is an acceptable dbcs mapping for 'wch' */
static inline int is_valid_dbcs_mapping( const struct dbcs_table *table, int flags,
WCHAR wch, unsigned short ch )
{
if (ch == table->info.def_char && wch != table->info.def_unicode_char) return 0;
if (flags & WC_NO_BEST_FIT_CHARS)
{
/* check if char maps back to the same Unicode value */
if (ch & 0xff00)
{
unsigned char off = table->cp2uni_leadbytes[ch >> 8];
return (table->cp2uni[(off << 8) + (ch & 0xff)] == wch);
}
return (table->cp2uni[ch & 0xff] == wch);
}
return 1;
}
/* query necessary dst length for src string */
static int get_length_dbcs( const struct dbcs_table *table, int flags,
const WCHAR *src, unsigned int srclen,
const char *defchar )
{
const unsigned short * const uni2cp_low = table->uni2cp_low;
const unsigned short * const uni2cp_high = table->uni2cp_high;
WCHAR defchar_value = table->info.def_char;
WCHAR composed;
int len;
if (!defchar && !(flags & WC_COMPOSITECHECK))
{
for (len = 0; srclen; srclen--, src++, len++)
{
if (uni2cp_low[uni2cp_high[*src >> 8] + (*src & 0xff)] & 0xff00) len++;
}
return len;
}
if (defchar) defchar_value = defchar[1] ? ((defchar[0] << 8) | defchar[1]) : defchar[0];
for (len = 0; srclen; len++, srclen--, src++)
{
unsigned short res;
WCHAR wch = *src;
if ((flags & WC_COMPOSITECHECK) && (srclen > 1) && (composed = compose(src)))
{
/* now check if we can use the composed char */
res = uni2cp_low[uni2cp_high[composed >> 8] + (composed & 0xff)];
if (is_valid_dbcs_mapping( table, flags, composed, res ))
{
/* we have a good mapping for the composed char, use it */
if (res & 0xff00) len++;
src++;
srclen--;
continue;
}
/* no mapping for the composed char, check the other flags */
if (flags & WC_DEFAULTCHAR) /* use the default char instead */
{
if (defchar_value & 0xff00) len++;
src++; /* skip the non-spacing char */
srclen--;
continue;
}
if (flags & WC_DISCARDNS) /* skip the second char of the composition */
{
src++;
srclen--;
}
/* WC_SEPCHARS is the default */
}
res = uni2cp_low[uni2cp_high[wch >> 8] + (wch & 0xff)];
if (!is_valid_dbcs_mapping( table, flags, wch, res )) res = defchar_value;
if (res & 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 unsigned short * const uni2cp_low = table->uni2cp_low;
const unsigned short * const uni2cp_high = table->uni2cp_high;
WCHAR defchar_value = table->info.def_char;
WCHAR composed;
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;
WCHAR wch = *src;
if ((flags & WC_COMPOSITECHECK) && (srclen > 1) && (composed = compose(src)))
{
/* now check if we can use the composed char */
res = uni2cp_low[uni2cp_high[composed >> 8] + (composed & 0xff)];
if (is_valid_dbcs_mapping( table, flags, composed, res ))
{
/* we have a good mapping for the composed char, use it */
src++;
srclen--;
goto output_char;
}
/* no mapping for the composed char, check the other flags */
if (flags & WC_DEFAULTCHAR) /* use the default char instead */
{
res = defchar_value;
*used = 1;
src++; /* skip the non-spacing char */
srclen--;
goto output_char;
}
if (flags & WC_DISCARDNS) /* skip the second char of the composition */
{
src++;
srclen--;
}
/* WC_SEPCHARS is the default */
}
res = uni2cp_low[uni2cp_high[wch >> 8] + (wch & 0xff)];
if (!is_valid_dbcs_mapping( table, flags, wch, res ))
{
res = defchar_value;
*used = 1;
}
output_char:
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 get_length_sbcs( &table->sbcs, flags, src, 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, flags, src, srclen, defchar );
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 );
}
}