1  /* Generate random integers.
       2  
       3     Copyright (C) 2006-2023 Free Software Foundation, Inc.
       4  
       5     This program is free software: you can redistribute it and/or modify
       6     it under the terms of the GNU General Public License as published by
       7     the Free Software Foundation, either version 3 of the License, or
       8     (at your option) any later version.
       9  
      10     This program 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
      13     GNU General Public License for more details.
      14  
      15     You should have received a copy of the GNU General Public License
      16     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      17  
      18  /* Written by Paul Eggert.  */
      19  
      20  #ifndef RANDINT_H
      21  
      22  # define RANDINT_H 1
      23  
      24  # include <stdint.h>
      25  
      26  # include "randread.h"
      27  
      28  /* An unsigned integer type, used for random integers, and its maximum
      29     value.  */
      30  typedef uintmax_t randint;
      31  # define RANDINT_MAX UINTMAX_MAX
      32  
      33  struct randint_source;
      34  
      35  void randint_free (struct randint_source *) _GL_ATTRIBUTE_NONNULL ();
      36  int randint_all_free (struct randint_source *) _GL_ATTRIBUTE_NONNULL ();
      37  struct randint_source *randint_new (struct randread_source *)
      38    _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_DEALLOC (randint_free, 1)
      39    _GL_ATTRIBUTE_NONNULL () _GL_ATTRIBUTE_RETURNS_NONNULL;
      40  struct randint_source *randint_all_new (char const *, size_t)
      41    _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_DEALLOC (randint_all_free, 1);
      42  struct randread_source *randint_get_source (struct randint_source const *)
      43    _GL_ATTRIBUTE_NONNULL () _GL_ATTRIBUTE_PURE;
      44  randint randint_genmax (struct randint_source *, randint genmax)
      45    _GL_ATTRIBUTE_NONNULL ();
      46  
      47  /* Consume random data from *S to generate a random number in the range
      48     0 .. CHOICES-1.  CHOICES must be nonzero.  */
      49  static inline randint
      50  randint_choose (struct randint_source *s, randint choices)
      51  {
      52    return randint_genmax (s, choices - 1);
      53  }
      54  
      55  #endif