blob: 291537f800f3705cffd50a570e9186a328c674a1 [file] [log] [blame]
/*
* This code was written by Rich Felker in 2010; no copyright is claimed.
* This code is in the public domain. Attribution is appreciated but
* unnecessary.
*/
#include <stdlib.h>
#include <inttypes.h>
#include <wchar.h>
#include <errno.h>
#include "internal.h"
size_t mbrtowc(wchar_t *wc, const char *src, size_t n, mbstate_t *st)
{
static unsigned internal_state;
unsigned c;
const unsigned char *s = (const void *)src;
const unsigned N = n;
if (!st) st = (void *)&internal_state;
c = *(unsigned *)st;
if (!s) {
s = (void *)"";
wc = (void *)&wc;
n = 1;
} else if (!wc) wc = (void *)&wc;
if (!n) return -2;
if (!c) {
if (*s < 0x80) return !!(*wc = *s);
if (*s-SA > SB-SA) goto ilseq;
c = bittab[*s++-SA]; n--;
}
if (n) {
if (OOB(c,*s)) goto ilseq;
loop:
c = c<<6 | *s++-0x80; n--;
if (!(c&(1U<<31))) {
*(unsigned *)st = 0;
*wc = c;
return N-n;
}
if (n) {
if (*s-0x80u >= 0x40) goto ilseq;
goto loop;
}
}
*(unsigned *)st = c;
return -2;
ilseq:
*(unsigned *)st = FAILSTATE;
errno = EILSEQ;
return -1;
}