/*-
 * Copyright (c)2001 Citrus Project,
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $Citrus$

  NetBSD: fgetwc.c,v 1.5 2006/07/03 17:06:36 tnozaki Exp
 */
#include  <LibConfig.h>
#include  <sys/EfiCdefs.h>

#include  <assert.h>
#include  <errno.h>
#include  <stdio.h>
#include  <wchar.h>
#include  "reentrant.h"
#include  "local.h"

wint_t
__fgetwc_unlock(FILE *fp)
{
  struct wchar_io_data *wcio;
  mbstate_t *st;
  wchar_t wc;
  size_t size;

  _DIAGASSERT(fp != NULL);

  _SET_ORIENTATION(fp, 1);
  wcio = WCIO_GET(fp);
  if (wcio == 0) {
    errno = ENOMEM;
    return WEOF;
  }

  /* if there're ungetwc'ed wchars, use them */
  if (wcio->wcio_ungetwc_inbuf) {
    wc = wcio->wcio_ungetwc_buf[--wcio->wcio_ungetwc_inbuf];

    return wc;
  }

  st = &wcio->wcio_mbstate_in;

  do {
    char c;
    int ch = __sgetc(fp);

    if (ch == EOF) {
      return WEOF;
    }

    c = (char)ch;
    size = mbrtowc(&wc, &c, 1, st);
    if (size == (size_t)-1) {
      errno = EILSEQ;
      fp->_flags |= __SERR;
      return WEOF;
    }
  } while (size == (size_t)-2);

  _DIAGASSERT(size == 1);

  return wc;
}

wint_t
fgetwc(FILE *fp)
{
  wint_t r;

  _DIAGASSERT(fp != NULL);

  FLOCKFILE(fp);
  r = __fgetwc_unlock(fp);
  FUNLOCKFILE(fp);

  return (r);
}