1  /* Test random.
       2     Copyright (C) 2008-2023 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 of the License, or
       7     (at your option) 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  #include <config.h>
      18  
      19  #include <stdlib.h>
      20  
      21  #include "signature.h"
      22  SIGNATURE_CHECK (srandom, void, (unsigned int));
      23  SIGNATURE_CHECK (initstate, char *, (unsigned int, char *, size_t));
      24  SIGNATURE_CHECK (setstate, char *, (char *));
      25  SIGNATURE_CHECK (random, long, (void));
      26  
      27  #include <time.h>
      28  
      29  #include "macros.h"
      30  
      31  int
      32  main ()
      33  {
      34    char buf[128];
      35    unsigned int i;
      36    unsigned int n_big = 0;
      37  
      38    initstate (time (NULL), buf, sizeof buf);
      39    for (i = 0; i < 1000; i++)
      40      {
      41        long r = random ();
      42        ASSERT (0 <= r);
      43        if (RAND_MAX / 2 < r)
      44          ++n_big;
      45      }
      46  
      47    /* Fail if none of the numbers were larger than RAND_MAX / 2.  */
      48    return !n_big;
      49  }