/*
 * Copyright 2013 Garrett D'Amore <garrett@damore.org>
 * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
 * Copyright (c) 2002-2004 Tim J. Robbins.
 * 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.
 */

#include "lint.h"
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <locale.h>
#include <wchar.h>
#include "mblocal.h"
#include "localeimpl.h"
#include "lctype.h"

size_t
wcsnrtombs_l(char *_RESTRICT_KYWD dst, const wchar_t **_RESTRICT_KYWD src,
    size_t nwc, size_t len, mbstate_t *_RESTRICT_KYWD ps, locale_t loc)
{
        static mbstate_t mbs;

        if (ps == NULL)
                ps = &mbs;
        return (loc->ctype->lc_wcsnrtombs(dst, src, nwc, len, ps));
}

size_t
wcsnrtombs(char *_RESTRICT_KYWD dst, const wchar_t **_RESTRICT_KYWD src,
    size_t nwc, size_t len, mbstate_t *_RESTRICT_KYWD ps)
{
        return (wcsnrtombs_l(dst, src, nwc, len, ps, uselocale(NULL)));
}

size_t
__wcsnrtombs_std(char *_RESTRICT_KYWD dst, const wchar_t **_RESTRICT_KYWD src,
    size_t nwc, size_t len, mbstate_t *_RESTRICT_KYWD ps,
    wcrtomb_pfn_t pwcrtomb)
{
        mbstate_t mbsbak;
        char buf[MB_LEN_MAX];
        const wchar_t *s;
        size_t nbytes;
        size_t nb;

        s = *src;
        nbytes = 0;

        if (dst == NULL) {
                while (nwc-- > 0) {
                        if ((nb = pwcrtomb(buf, *s, ps)) == (size_t)-1)
                                /* Invalid character - wcrtomb() sets errno. */
                                return ((size_t)-1);
                        else if (*s == L'\0')
                                return (nbytes + nb - 1);
                        s++;
                        nbytes += nb;
                }
                return (nbytes);
        }

        while (len > 0 && nwc-- > 0) {
                if (len > (size_t)MB_CUR_MAX) {
                        /* Enough space to translate in-place. */
                        if ((nb = pwcrtomb(dst, *s, ps)) == (size_t)-1) {
                                *src = s;
                                return ((size_t)-1);
                        }
                } else {
                        /*
                         * May not be enough space; use temp. buffer.
                         *
                         * We need to save a copy of the conversion state
                         * here so we can restore it if the multibyte
                         * character is too long for the buffer.
                         */
                        mbsbak = *ps;
                        if ((nb = pwcrtomb(buf, *s, ps)) == (size_t)-1) {
                                *src = s;
                                return ((size_t)-1);
                        }
                        if (nb > (int)len) {
                                /* MB sequence for character won't fit. */
                                *ps = mbsbak;
                                break;
                        }
                        (void) memcpy(dst, buf, nb);
                }
                if (*s == L'\0') {
                        *src = NULL;
                        return (nbytes + nb - 1);
                }
                s++;
                dst += nb;
                len -= nb;
                nbytes += nb;
        }
        *src = s;
        return (nbytes);
}