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| | /*
* 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 *restrict wc, const char *restrict src, size_t n, mbstate_t *restrict st)
{
static unsigned internal_state;
unsigned c;
const unsigned char *s = (const void *)src;
const unsigned N = n;
if (!n) return -2;
if (!st) st = (void *)&internal_state;
c = *(unsigned *)st;
if (!s) {
s = (void *)"";
wc = (void *)&wc;
n = 1;
} else if (!wc) wc = (void *)&wc;
/* This condition can only be true if *s<0x80 and c==0 */
if (*s + c < 0x80) return !!(*wc = *s);
if (!c) {
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;
}
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