size_t _mbclen(const unsigned char *s)
size_t _mbclen2(const unsigned int s)
int mblen(const char *str, size_t size)
size_t __cdecl mbrlen(const char *str, size_t len, mbstate_t *state)
_Check_return_ _CRTIMP int __cdecl _ismbbtrail(_In_ unsigned int _C)
int __cdecl _ismbblead(unsigned int)