| 1 | #include <stdlib.h> |
| 2 | #include <wchar.h> |
| 3 | #include <errno.h> |
| 4 | #include "internal.h" |
| 5 | |
| 6 | size_t mbrtowc(wchar_t *restrict wc, const char *restrict src, size_t n, mbstate_t *restrict st) |
| 7 | { |
| 8 | static unsigned internal_state; |
| 9 | unsigned c; |
| 10 | const unsigned char *s = (const void *)src; |
| 11 | const size_t N = n; |
| 12 | wchar_t dummy; |
| 13 | |
| 14 | if (!st) st = (void *)&internal_state; |
| 15 | c = *(unsigned *)st; |
| 16 | |
| 17 | if (!s) { |
| 18 | if (c) goto ilseq; |
| 19 | return 0; |
| 20 | } else if (!wc) wc = &dummy; |
| 21 | |
| 22 | if (!n) return -2; |
| 23 | if (!c) { |
| 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--; |
| 28 | } |
| 29 | |
| 30 | if (n) { |
| 31 | if (OOB(c,*s)) goto ilseq; |
| 32 | loop: |
| 33 | c = c<<6 | *s++-0x80; n--; |
| 34 | if (!(c&(1U<<31))) { |
| 35 | *(unsigned *)st = 0; |
| 36 | *wc = c; |
| 37 | return N-n; |
| 38 | } |
| 39 | if (n) { |
| 40 | if (*s-0x80u >= 0x40) goto ilseq; |
| 41 | goto loop; |
| 42 | } |
| 43 | } |
| 44 | |
| 45 | *(unsigned *)st = c; |
| 46 | return -2; |
| 47 | ilseq: |
| 48 | *(unsigned *)st = 0; |
| 49 | errno = EILSEQ; |
| 50 | return -1; |
| 51 | } |