src/stdio/vswscanf.c

   1 #include "stdio_impl.h"
   2 #include <wchar.h>
   3
   4 static 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
  27 int 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                 .read = wstring_read, .lock = -1
  34         };
  35         return vfwscanf(&f, fmt, ap);
  36 }
  37
  38 weak_alias(vswscanf,__isoc99_vswscanf);