lib/libc/stdio/fgetwc.c

   1 /* $NetBSD: fgetwc.c,v 1.4 2005/06/12 05:21:27 lukem 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         mbstate_t *st;
  48         wchar_t wc;
  49         size_t size;
  50
  51         _DIAGASSERT(fp != NULL);
  52
  53         _SET_ORIENTATION(fp, 1);
  54         wcio = WCIO_GET(fp);
  55         if (wcio == 0) {
  56                 errno = ENOMEM;
  57                 return WEOF;
  58         }
  59
  60         /* if there're ungetwc'ed wchars, use them */
  61         if (wcio->wcio_ungetwc_inbuf) {
  62                 wc = wcio->wcio_ungetwc_buf[--wcio->wcio_ungetwc_inbuf];
  63
  64                 return wc;
  65         }
  66
  67         st = &wcio->wcio_mbstate_in;
  68
  69         do {
  70                 char c;
  71                 int ch = __sgetc(fp);
  72
  73                 if (ch == EOF) {
  74                         return WEOF;
  75                 }
  76
  77                 c = ch;
  78                 size = mbrtowc(&wc, &c, 1, st);
  79                 if (size == (size_t)-1) {
  80                         errno = EILSEQ;
  81                         return WEOF;
  82                 }
  83         } while (size == (size_t)-2);
  84
  85         _DIAGASSERT(size == 1);
  86
  87         return wc;
  88 }
  89
  90 wint_t
  91 fgetwc(FILE *fp)
  92 {
  93         wint_t r;
  94
  95         _DIAGASSERT(fp != NULL);
  96
  97         FLOCKFILE(fp);
  98         r = __fgetwc_unlock(fp);
  99         FUNLOCKFILE(fp);
 100
 101         return (r);
 102 }
 103