lib/libc/stdio/fgetwc.c

   1 /* $NetBSD: fgetwc.c,v 1.8 2007/04/01 18:35:53 tnozaki Exp $ */
   2 /* $DragonFly: src/lib/libc/stdio/fgetwc.c,v 1.1 2005/07/25 00:37:41 joerg Exp $ */
   3
   4 /*-
   5  * Copyright (c)2001 Citrus Project,
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * $Citrus$
  30  */
  31
  32 #include "namespace.h"
  33 #include <assert.h>
  34 #include <errno.h>
  35 #include <stdio.h>
  36 #include <wchar.h>
  37 #include "un-namespace.h"
  38
  39 #include "libc_private.h"
  40 #include "local.h"
  41 #include "priv_stdio.h"
  42
  43 wint_t
  44 __fgetwc_unlock(FILE *fp)
  45 {
  46         struct wchar_io_data *wcio;
  47         wchar_t wc;
  48         size_t nr;
  49
  50         _DIAGASSERT(fp != NULL);
  51
  52         _SET_ORIENTATION(fp, 1);
  53         wcio = WCIO_GET(fp);
  54         _DIAGASSERT(wcio != NULL);
  55
  56         /* if there're ungetwc'ed wchars, use them */
  57         if (wcio->wcio_ungetwc_inbuf)
  58                 return(wcio->wcio_ungetwc_buf[--wcio->wcio_ungetwc_inbuf]);
  59
  60         if (fp->pub._r <= 0) {
  61 restart:
  62                 if (__srefill(fp) != 0)
  63                         return WEOF;
  64         }
  65         nr = mbrtowc(&wc, (const char *)fp->pub._p,
  66             (size_t)fp->pub._r, &wcio->wcio_mbstate_in);
  67         if (nr == (size_t)-1) {
  68                 fp->pub._flags |= __SERR;
  69                 return WEOF;
  70         } else if (nr == (size_t)-2) {
  71                 fp->pub._p += fp->pub._r;
  72                 fp->pub._r = 0;
  73                 goto restart;
  74         }
  75         if (wc == L'\0') {
  76                 while (*fp->pub._p != '\0') {
  77                         ++fp->pub._p;
  78                         --fp->pub._r;
  79                 }
  80                 nr = 1;
  81         }
  82         fp->pub._p += nr;
  83         fp->pub._r -= nr;
  84
  85         return wc;
  86 }
  87
  88 wint_t
  89 fgetwc(FILE *fp)
  90 {
  91         wint_t r;
  92
  93         _DIAGASSERT(fp != NULL);
  94
  95         FLOCKFILE(fp);
  96         r = __fgetwc_unlock(fp);
  97         FUNLOCKFILE(fp);
  98
  99         return (r);
 100 }
 101