lib/libc/string/strerror.c

   1 /*      $NetBSD: strerror.c,v 1.17 2015/01/20 18:31:25 christos Exp $   */
   2
   3 /*
   4  * Copyright (c) 1988 Regents of the University of California.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 __RCSID("$NetBSD: strerror.c,v 1.17 2015/01/20 18:31:25 christos Exp $");
  34
  35 #define __SETLOCALE_SOURCE__
  36
  37 #include "namespace.h"
  38 #include <errno.h>
  39 #include <limits.h>
  40 #include <locale.h>
  41 #include <stdlib.h>
  42 #include <string.h>
  43
  44 #include "extern.h"
  45 #ifdef _REENTRANT
  46 #include "reentrant.h"
  47 #endif
  48 #include "setlocale_local.h"
  49
  50 __weak_alias(strerror_l, _strerror_l)
  51
  52 __aconst char *
  53 strerror(int num)
  54 {
  55
  56         return strerror_l(num, _current_locale());
  57 }
  58
  59 #ifdef _REENTRANT
  60 static thread_key_t strerror_key;
  61 static once_t strerror_once = ONCE_INITIALIZER;
  62
  63 static void
  64 strerror_setup(void)
  65 {
  66
  67         thr_keycreate(&strerror_key, free);
  68 }
  69 #endif
  70
  71 __aconst char *
  72 strerror_l(int num, locale_t loc)
  73 {
  74         int error;
  75 #ifdef _REENTRANT
  76         char *buf;
  77
  78         thr_once(&strerror_once, strerror_setup);
  79         buf = thr_getspecific(strerror_key);
  80         if (buf == NULL) {
  81                 buf = malloc(NL_TEXTMAX);
  82                 if (buf == NULL) {
  83                         static char fallback_buf[NL_TEXTMAX];
  84                         buf = fallback_buf;
  85                 }
  86                 thr_setspecific(strerror_key, buf);
  87         }
  88 #else
  89         static char buf[NL_TEXTMAX];
  90 #endif
  91
  92         error = _strerror_lr(num, buf, NL_TEXTMAX, loc);
  93         if (error)
  94                 errno = error;
  95         return buf;
  96 }