string/strerror_l.c

   1 /* Copyright (C) 2007-2023 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <libintl.h>
  19 #include <locale.h>
  20 #include <stdio.h>
  21 #include <string.h>
  22 #include <tls-internal.h>
  23
  24
  25 static const char *
  26 translate (const char *str, locale_t loc)
  27 {
  28   locale_t oldloc = __uselocale (loc);
  29   const char *res = _(str);
  30   __uselocale (oldloc);
  31   return res;
  32 }
  33
  34
  35 /* Return a string describing the errno code in ERRNUM.  */
  36 char *
  37 __strerror_l (int errnum, locale_t loc)
  38 {
  39   int saved_errno = errno;
  40   char *err = (char *) __get_errlist (errnum);
  41   if (__glibc_unlikely (err == NULL))
  42     {
  43       struct tls_internal_t *tls_internal = __glibc_tls_internal ();
  44       free (tls_internal->strerror_l_buf);
  45       if (__asprintf (&tls_internal->strerror_l_buf, "%s%d",
  46                       translate ("Unknown error ", loc), errnum) > 0)
  47         err = tls_internal->strerror_l_buf;
  48       else
  49         {
  50           /* The memory was freed above.  */
  51           tls_internal->strerror_l_buf = NULL;
  52           /* Provide a fallback translation.  */
  53           err = (char *) translate ("Unknown error", loc);
  54         }
  55     }
  56   else
  57     err = (char *) translate (err, loc);
  58
  59   __set_errno (saved_errno);
  60   return err;
  61 }
  62 weak_alias (__strerror_l, strerror_l)
  63 libc_hidden_def (__strerror_l)