/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1988, 1993
 *      The Regents of the University of California.  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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 */

#if defined(NLS)
#include <nl_types.h>
#endif

#include <limits.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>

#include <ssp/ssp.h>

#include "errlst.h"
#include "../locale/xlocale_private.h"
#include "libc_private.h"

/*
 * Define buffer big enough to contain delimiter (": ", 2 bytes),
 * 64-bit signed integer converted to ASCII decimal (19 bytes) with
 * optional leading sign (1 byte), and a trailing NUL.
 */
#define EBUFSIZE        (2 + 19 + 1 + 1)

/*
 * Doing this by hand instead of linking with stdio(3) avoids bloat for
 * statically linked binaries.
 */
static void
errstr(int num, const char *uprefix, char *buf, size_t len)
{
        char *t;
        unsigned int uerr;
        char tmp[EBUFSIZE];

        t = tmp + sizeof(tmp);
        *--t = '\0';
        uerr = (num >= 0) ? num : -num;
        do {
                *--t = "0123456789"[uerr % 10];
        } while (uerr /= 10);
        if (num < 0)
                *--t = '-';
        *--t = ' ';
        *--t = ':';
        strlcpy(buf, uprefix, len);
        strlcat(buf, t, len);
}

int
__strerror_rl(int errnum, char *strerrbuf, size_t buflen, locale_t locale)
{
        int retval = 0;
#if defined(NLS)
        int saved_errno = errno;
        nl_catd catd;

        catd = __catopen_l("libc", NL_CAT_LOCALE, locale);
#endif

        if (errnum < 0 || errnum >= __hidden_sys_nerr) {
                errstr(errnum,
#if defined(NLS)
                    catgets(catd, 1, 0xffff, __uprefix),
#else
                    __uprefix,
#endif
                   strerrbuf, buflen);
                retval = EINVAL;
        } else {
                if (strlcpy(strerrbuf,
#if defined(NLS)
                    catgets(catd, 1, errnum, __hidden_sys_errlist[errnum]),
#else
                    __hidden_sys_errlist[errnum],
#endif
                    buflen) >= buflen)
                        retval = ERANGE;
        }

#if defined(NLS)
        catclose(catd);
        errno = saved_errno;
#endif

        return (retval);
}

int
__ssp_real(strerror_r)(int errnum, char *strerrbuf, size_t buflen)
{
        return (__strerror_rl(errnum, strerrbuf, buflen, __get_locale()));
}

char *
strerror_l(int num, locale_t locale)
{
        static _Thread_local char ebuf[NL_TEXTMAX];

        if (__strerror_rl(num, ebuf, sizeof(ebuf), locale) != 0)
                errno = EINVAL;
        return (ebuf);
}

char *
strerror(int num)
{
        static char ebuf[NL_TEXTMAX];

        if (__strerror_rl(num, ebuf, sizeof(ebuf), __get_locale()) != 0)
                errno = EINVAL;
        return (ebuf);
}