/*-
 * Copyright (c) 2002-2004 Tim J. Robbins.
 * All rights reserved.
 *
 * Copyright (c) 2011 The FreeBSD Foundation
 * All rights reserved.
 * Portions of this software were developed by David Chisnall
 * under sponsorship from the FreeBSD Foundation.
 *
 * 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.
 *
 * $FreeBSD: head/lib/libc/stdio/fgetwc.c 234799 2012-04-29 16:28:39Z das $
 */


#include "namespace.h"
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <wchar.h>
#include "un-namespace.h"
#include "libc_private.h"
#include "local.h"
#include "mblocal.h"
#include "xlocale_private.h"

/*
 * MT-safe version.
 */
wint_t
fgetwc_l(FILE *fp, locale_t locale)
{
        wint_t r;
        FIX_LOCALE(locale);

        FLOCKFILE(fp);
        ORIENT(fp, 1);
        r = __fgetwc(fp, locale);
        FUNLOCKFILE(fp);

        return (r);
}

wint_t
fgetwc(FILE *fp)
{
        return fgetwc_l(fp, __get_locale());
}

/*
 * Internal (non-MPSAFE) version of fgetwc().  This version takes an
 * mbstate_t argument specifying the initial conversion state.  For
 * wide streams, this should always be fp->_mbstate.  On return, *nread
 * is set to the number of bytes read.
 */
wint_t 
__fgetwc_mbs(FILE *fp, mbstate_t *mbs, int *nread, locale_t locale)
{
        wchar_t wc;
        size_t nconv;
        struct xlocale_ctype *l = XLOCALE_CTYPE(locale);

        if (fp->pub._r <= 0 && __srefill(fp)) {
                *nread = 0;
                return (WEOF);
        }
        if (MB_CUR_MAX == 1) {
                /* Fast path for single-byte encodings. */
                wc = *fp->pub._p++;
                fp->pub._r--;
                *nread = 1;
                return (wc);
        }
        *nread = 0;
        do {
                nconv = l->__mbrtowc(&wc, fp->pub._p, fp->pub._r, mbs);
                if (nconv == (size_t)-1)
                        break;
                else if (nconv == (size_t)-2)
                        continue;
                else if (nconv == 0) {
                        fp->pub._p++;
                        fp->pub._r--;
                        (*nread)++;
                        return (L'\0');
                } else {
                        fp->pub._p += nconv;
                        fp->pub._r -= nconv;
                        *nread += nconv;
                        return (wc);
                }
        } while (__srefill(fp) == 0);
        fp->pub._flags |= __SERR;
        errno = EILSEQ;
        return (WEOF);
}