wine/unicode/mbtowc.c

166 lines
5 KiB
C

/*
* MultiByteToWideChar implementation
*
* Copyright 2000 Alexandre Julliard
*/
#include <string.h>
#include "winnls.h"
#include "wine/unicode.h"
/* check src string for invalid chars; return non-zero if invalid char found */
static inline int check_invalid_chars_sbcs( const struct sbcs_table *table,
const unsigned char *src, unsigned int srclen )
{
const WCHAR * const cp2uni = table->cp2uni;
while (srclen)
{
if (cp2uni[*src] == table->info.def_unicode_char && *src != table->info.def_char)
break;
src++;
srclen--;
}
return srclen;
}
/* mbstowcs for single-byte code page */
/* all lengths are in characters, not bytes */
static inline int mbstowcs_sbcs( const struct sbcs_table *table,
const unsigned char *src, unsigned int srclen,
WCHAR *dst, unsigned int dstlen )
{
const WCHAR * const cp2uni = table->cp2uni;
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] = cp2uni[src[15]];
case 15: dst[14] = cp2uni[src[14]];
case 14: dst[13] = cp2uni[src[13]];
case 13: dst[12] = cp2uni[src[12]];
case 12: dst[11] = cp2uni[src[11]];
case 11: dst[10] = cp2uni[src[10]];
case 10: dst[9] = cp2uni[src[9]];
case 9: dst[8] = cp2uni[src[8]];
case 8: dst[7] = cp2uni[src[7]];
case 7: dst[6] = cp2uni[src[6]];
case 6: dst[5] = cp2uni[src[5]];
case 5: dst[4] = cp2uni[src[4]];
case 4: dst[3] = cp2uni[src[3]];
case 3: dst[2] = cp2uni[src[2]];
case 2: dst[1] = cp2uni[src[1]];
case 1: dst[0] = cp2uni[src[0]];
case 0: break;
}
if (srclen < 16) return ret;
dst += 16;
src += 16;
srclen -= 16;
}
}
/* query necessary dst length for src string */
static inline int get_length_dbcs( const struct dbcs_table *table,
const unsigned char *src, unsigned int srclen )
{
const unsigned char * const cp2uni_lb = table->cp2uni_leadbytes;
int len;
for (len = 0; srclen; srclen--, src++, len++)
{
if (cp2uni_lb[*src])
{
if (!--srclen) break; /* partial char, ignore it */
src++;
}
}
return len;
}
/* check src string for invalid chars; return non-zero if invalid char found */
static inline int check_invalid_chars_dbcs( const struct dbcs_table *table,
const unsigned char *src, unsigned int srclen )
{
const WCHAR * const cp2uni = table->cp2uni;
const unsigned char * const cp2uni_lb = table->cp2uni_leadbytes;
while (srclen)
{
unsigned char off = cp2uni_lb[*src];
if (off) /* multi-byte char */
{
if (srclen == 1) break; /* partial char, error */
if (cp2uni[(off << 8) + src[1]] == table->info.def_unicode_char &&
((src[0] << 8) | src[1]) != table->info.def_char) break;
src++;
srclen--;
}
else if (cp2uni[*src] == table->info.def_unicode_char &&
*src != table->info.def_char) break;
src++;
srclen--;
}
return srclen;
}
/* mbstowcs for double-byte code page */
/* all lengths are in characters, not bytes */
static inline int mbstowcs_dbcs( const struct dbcs_table *table,
const unsigned char *src, unsigned int srclen,
WCHAR *dst, unsigned int dstlen )
{
const WCHAR * const cp2uni = table->cp2uni;
const unsigned char * const cp2uni_lb = table->cp2uni_leadbytes;
int len;
for (len = dstlen; srclen && len; len--, srclen--, src++, dst++)
{
unsigned char off = cp2uni_lb[*src];
if (off)
{
if (!--srclen) break; /* partial char, ignore it */
src++;
*dst = cp2uni[(off << 8) + *src];
}
else *dst = cp2uni[*src];
}
if (srclen) return -1; /* overflow */
return dstlen - len;
}
/* return -1 on dst buffer overflow, -2 on invalid input char */
int cp_mbstowcs( const union cptable *table, int flags,
const char *src, int srclen,
WCHAR *dst, int dstlen )
{
if (table->info.char_size == 1)
{
if (flags & MB_ERR_INVALID_CHARS)
{
if (check_invalid_chars_sbcs( &table->sbcs, src, srclen )) return -2;
}
if (!dstlen) return srclen;
return mbstowcs_sbcs( &table->sbcs, src, srclen, dst, dstlen );
}
else /* mbcs */
{
if (flags & MB_ERR_INVALID_CHARS)
{
if (check_invalid_chars_dbcs( &table->dbcs, src, srclen )) return -2;
}
if (!dstlen) return get_length_dbcs( &table->dbcs, src, srclen );
return mbstowcs_dbcs( &table->dbcs, src, srclen, dst, dstlen );
}
}