src/multibyte/wcsnrtombs.c

   1 #include <wchar.h>
   2
   3 size_t wcsnrtombs(char *restrict dst, const wchar_t **restrict wcs, size_t wn, size_t n, mbstate_t *restrict st)
   4 {
   5         size_t l, cnt=0, n2;
   6         char *s, buf[256];
   7         const wchar_t *ws = *wcs;
   8
   9         if (!dst) s = buf, n = sizeof buf;
  10         else s = dst;
  11
  12         while ( ws && n && ( (n2=wn)>=n || n2>32 ) ) {
  13                 if (n2>=n) n2=n;
  14                 wn -= n2;
  15                 l = wcsrtombs(s, &ws, n2, 0);
  16                 if (!(l+1)) {
  17                         cnt = l;
  18                         n = 0;
  19                         break;
  20                 }
  21                 if (s != buf) {
  22                         s += l;
  23                         n -= l;
  24                 }
  25                 cnt += l;
  26         }
  27         if (ws) while (n && wn) {
  28                 l = wcrtomb(s, *ws, 0);
  29                 if ((l+1)<=1) {
  30                         if (!l) ws = 0;
  31                         else cnt = l;
  32                         break;
  33                 }
  34                 ws++; wn--;
  35                 /* safe - this loop runs fewer than sizeof(buf) times */
  36                 s+=l; n-=l;
  37                 cnt += l;
  38         }
  39         if (dst) *wcs = ws;
  40         return cnt;
  41 }