lib/randint.h

   1 /* Generate random integers.
   2
   3    Copyright (C) 2006 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 2, or (at your option)
   8    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, write to the Free Software Foundation,
  17    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  18
  19 /* Written by Paul Eggert.  */
  20
  21 #ifndef RANDINT_H
  22
  23 # define RANDINT_H 1
  24
  25 # include <stdint.h>
  26
  27 # include "randread.h"
  28
  29 /* An unsigned integer type, used for random integers, and its maximum
  30    value.  */
  31 typedef uintmax_t randint;
  32 # define RANDINT_MAX UINTMAX_MAX
  33
  34 struct randint_source;
  35
  36 struct randint_source *randint_new (struct randread_source *);
  37 struct randint_source *randint_all_new (char const *, size_t);
  38 struct randread_source *randint_get_source (struct randint_source const *);
  39 randint randint_genmax (struct randint_source *, randint genmax);
  40
  41 /* Consume random data from *S to generate a random number in the range
  42    0 .. CHOICES-1.  CHOICES must be nonzero.  */
  43 static inline randint
  44 randint_choose (struct randint_source *s, randint choices)
  45 {
  46   return randint_genmax (s, choices - 1);
  47 }
  48
  49 void randint_free (struct randint_source *);
  50 int randint_all_free (struct randint_source *);
  51
  52 #endif