1  /* Test of strerror() function.
       2     Copyright (C) 2007-2022 Free Software Foundation, Inc.
       3  
       4     This program is free software; you can redistribute it and/or modify
       5     it under the terms of the GNU General Public License as published by
       6     the Free Software Foundation, either version 3, or (at your option)
       7     any later version.
       8  
       9     This program 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
      12     GNU General Public License for more details.
      13  
      14     You should have received a copy of the GNU General Public License
      15     along with this program; if not, see <https://www.gnu.org/licenses/>.  */
      16  
      17  /* Written by Eric Blake <ebb9@byu.net>, 2007.  */
      18  
      19  #include <config.h>
      20  
      21  #include <string.h>
      22  
      23  #include "signature.h"
      24  SIGNATURE_CHECK (strerror, char *, (int));
      25  
      26  #include <errno.h>
      27  
      28  #include "macros.h"
      29  
      30  int
      31  main (void)
      32  {
      33    char *str;
      34  
      35    errno = 0;
      36    str = strerror (EACCES);
      37    ASSERT (str);
      38    ASSERT (*str);
      39    ASSERT (errno == 0);
      40  
      41    errno = 0;
      42    str = strerror (ETIMEDOUT);
      43    ASSERT (str);
      44    ASSERT (*str);
      45    ASSERT (errno == 0);
      46  
      47    errno = 0;
      48    str = strerror (EOVERFLOW);
      49    ASSERT (str);
      50    ASSERT (*str);
      51    ASSERT (errno == 0);
      52  
      53    /* POSIX requires strerror (0) to succeed.  Reject use of "Unknown
      54       error", but allow "Success", "No error", or even Solaris' "Error
      55       0" which are distinct patterns from true out-of-range strings.
      56       http://austingroupbugs.net/view.php?id=382  */
      57    errno = 0;
      58    str = strerror (0);
      59    ASSERT (str);
      60    ASSERT (*str);
      61    ASSERT (errno == 0);
      62    ASSERT (strstr (str, "nknown") == NULL);
      63    ASSERT (strstr (str, "ndefined") == NULL);
      64  
      65    /* POSIX requires strerror to produce a non-NULL result for all
      66       inputs; as an extension, we also guarantee a non-empty result.
      67       Reporting EINVAL is optional.  */
      68    errno = 0;
      69    str = strerror (-3);
      70    ASSERT (str);
      71    ASSERT (*str);
      72    ASSERT (errno == 0 || errno == EINVAL);
      73  
      74    return 0;
      75  }