6 size_t mbrtowc(wchar_t *restrict wc, const char *restrict src, size_t n, mbstate_t *restrict st)
8 static unsigned internal_state;
10 const unsigned char *s = (const void *)src;
14 if (!st) st = (void *)&internal_state;
20 } else if (!wc) wc = &dummy;
24 if (*s < 0x80) return !!(*wc = *s);
25 if (MB_CUR_MAX==1) return (*wc = CODEUNIT(*s)), 1;
26 if (*s-SA > SB-SA) goto ilseq;
27 c = bittab[*s++-SA]; n--;
31 if (OOB(c,*s)) goto ilseq;
33 c = c<<6 | *s++-0x80; n--;
40 if (*s-0x80u >= 0x40) goto ilseq;