/*      $NetBSD: strerror.c,v 1.18 2020/03/25 16:10:17 kre Exp $        */

/*
* Copyright (c) 1988 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.
*/

#include <sys/cdefs.h>
__RCSID("$NetBSD: strerror.c,v 1.18 2020/03/25 16:10:17 kre Exp $");

#define __SETLOCALE_SOURCE__

#include "namespace.h"
#include <errno.h>
#include <limits.h>
#include <locale.h>
#include <stdlib.h>
#include <string.h>

#include "extern.h"
#ifdef _REENTRANT
#include "reentrant.h"
#endif
#include "setlocale_local.h"

__weak_alias(strerror_l, _strerror_l)

__aconst char *
strerror(int num)
{

       return strerror_l(num, _current_locale());
}

#ifdef _REENTRANT
static thread_key_t strerror_key;
static once_t strerror_once = ONCE_INITIALIZER;

static void
strerror_setup(void)
{

       thr_keycreate(&strerror_key, free);
}
#endif

__aconst char *
strerror_l(int num, locale_t loc)
{
       int error;
#ifdef _REENTRANT
       char *buf;

       thr_once(&strerror_once, strerror_setup);
       buf = thr_getspecific(strerror_key);
       if (buf == NULL) {
               error = errno;
               buf = malloc(NL_TEXTMAX);
               errno = error;
               if (buf == NULL) {
                       static char fallback_buf[NL_TEXTMAX];
                       buf = fallback_buf;
               }
               thr_setspecific(strerror_key, buf);
       }
#else
       static char buf[NL_TEXTMAX];
#endif

       error = _strerror_lr(num, buf, NL_TEXTMAX, loc);
       if (error)
               errno = error;
       return buf;
}