1#include "stdio_impl.h"
 2#include <wchar.h>
 3
 4static size_t wstring_read(FILE *f, unsigned char *buf, size_t len)
 5{
 6	const wchar_t *src = f->cookie;
 7	size_t k;
 8
 9	if (!src) return 0;
10
11	k = wcsrtombs((void *)f->buf, &src, f->buf_size, 0);
12	if (k==(size_t)-1) {
13		f->rpos = f->rend = 0;
14		return 0;
15	}
16
17	f->rpos = f->buf;
18	f->rend = f->buf + k;
19	f->cookie = (void *)src;
20
21	if (!len || !k) return 0;
22
23	*buf = *f->rpos++;
24	return 1;
25}
26
27int vswscanf(const wchar_t *restrict s, const wchar_t *restrict fmt, va_list ap)
28{
29	unsigned char buf[256];
30	FILE f = {
31		.buf = buf, .buf_size = sizeof buf,
32		.cookie = (void *)s,
33#if defined(__wasilibc_unmodified_upstream) || defined(_REENTRANT)
34		.read = wstring_read, .lock = -1
35#else
36		.read = wstring_read
37#endif
38	};
39	return vfwscanf(&f, fmt, ap);
40}
41
42weak_alias(vswscanf,__isoc99_vswscanf);