1  /* Test for endgrent changing errno for BZ #24696
       2     Copyright (C) 2019-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <stdlib.h>
      20  #include <sys/types.h>
      21  #include <grp.h>
      22  #include <unistd.h>
      23  #include <errno.h>
      24  
      25  #include <support/check.h>
      26  #include <support/support.h>
      27  
      28  /* The following test verifies that if the db NSS Service is initialized
      29     with no database (getgrent), that a subsequent closure (endgrent) does
      30     not set errno. In the case of the db service it is not an error to close
      31     the service and so it should not set errno.  */
      32  
      33  static int
      34  do_test (void)
      35  {
      36    /* Just make sure it's not there, although usually it won't be.  */
      37    unlink ("/var/db/group.db");
      38  
      39    /* This, in conjunction with the testroot's nsswitch.conf, causes
      40       the nss_db module to be "connected" and initialized - but the
      41       testroot has no group.db, so no mapping will be created.  */
      42    getgrent ();
      43  
      44    errno = 0;
      45  
      46    /* Before the fix, this would call munmap (NULL) and set errno.  */
      47    endgrent ();
      48  
      49    if (errno != 0)
      50      FAIL_EXIT1 ("endgrent set errno to %d\n", errno);
      51  
      52    return 0;
      53  }
      54  #include <support/test-driver.c>