1#include "stdio_impl.h" 2#include "locale_impl.h" 3#include <wchar.h> 4#include <limits.h> 5#include <ctype.h> 6#include <string.h> 7 8wint_t ungetwc(wint_t c, FILE *f) 9{ 10 unsigned char mbc[MB_LEN_MAX]; 11 int l; 12 locale_t *ploc = &CURRENT_LOCALE, loc = *ploc; 13 14 FLOCK(f); 15 16 if (f->mode <= 0) fwide(f, 1); 17 *ploc = f->locale; 18 19 if (!f->rpos) __toread(f); 20 if (!f->rpos || c == WEOF || (l = wcrtomb((void *)mbc, c, 0)) < 0 || 21 f->rpos < f->buf - UNGET + l) { 22 FUNLOCK(f); 23 *ploc = loc; 24 return WEOF; 25 } 26 27 if (isascii(c)) *--f->rpos = c; 28 else memcpy(f->rpos -= l, mbc, l); 29 30 f->flags &= ~F_EOF; 31 32 FUNLOCK(f); 33 *ploc = loc; 34 return c; 35} 36