blob: 9b2f2dfbb023b6db8924bc7081c5c128594c8e1d [file] [log] [blame] [edit]
#include <stdint.h>
#include <wchar.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include "internal.h"
size_t mbsrtowcs(wchar_t *restrict ws, const char **restrict src, size_t wn, mbstate_t *restrict st)
{
const unsigned char *s = (const void *)*src;
size_t wn0 = wn;
unsigned c = 0;
if (st && (c = *(unsigned *)st)) {
if (ws) {
*(unsigned *)st = 0;
goto resume;
} else {
goto resume0;
}
}
if (MB_CUR_MAX==1) {
if (!ws) return strlen((const char *)s);
for (;;) {
if (!wn) {
*src = (const void *)s;
return wn0;
}
if (!*s) break;
c = *s++;
*ws++ = CODEUNIT(c);
wn--;
}
*ws = 0;
*src = 0;
return wn0-wn;
}
if (!ws) for (;;) {
#ifdef __GNUC__
typedef uint32_t __attribute__((__may_alias__)) w32;
if (*s-1u < 0x7f && (uintptr_t)s%4 == 0) {
while (!(( *(w32*)s | *(w32*)s-0x01010101) & 0x80808080)) {
s += 4;
wn -= 4;
}
}
#endif
if (*s-1u < 0x7f) {
s++;
wn--;
continue;
}
if (*s-SA > SB-SA) break;
c = bittab[*s++-SA];
resume0:
if (OOB(c,*s)) { s--; break; }
s++;
if (c&(1U<<25)) {
if (*s-0x80u >= 0x40) { s-=2; break; }
s++;
if (c&(1U<<19)) {
if (*s-0x80u >= 0x40) { s-=3; break; }
s++;
}
}
wn--;
c = 0;
} else for (;;) {
if (!wn) {
*src = (const void *)s;
return wn0;
}
#ifdef __GNUC__
typedef uint32_t __attribute__((__may_alias__)) w32;
if (*s-1u < 0x7f && (uintptr_t)s%4 == 0) {
while (wn>=5 && !(( *(w32*)s | *(w32*)s-0x01010101) & 0x80808080)) {
*ws++ = *s++;
*ws++ = *s++;
*ws++ = *s++;
*ws++ = *s++;
wn -= 4;
}
}
#endif
if (*s-1u < 0x7f) {
*ws++ = *s++;
wn--;
continue;
}
if (*s-SA > SB-SA) break;
c = bittab[*s++-SA];
resume:
if (OOB(c,*s)) { s--; break; }
c = (c<<6) | *s++-0x80;
if (c&(1U<<31)) {
if (*s-0x80u >= 0x40) { s-=2; break; }
c = (c<<6) | *s++-0x80;
if (c&(1U<<31)) {
if (*s-0x80u >= 0x40) { s-=3; break; }
c = (c<<6) | *s++-0x80;
}
}
*ws++ = c;
wn--;
c = 0;
}
if (!c && !*s) {
if (ws) {
*ws = 0;
*src = 0;
}
return wn0-wn;
}
errno = EILSEQ;
if (ws) *src = (const void *)s;
return -1;
}