rm_/lib/randint.h
2022-07-28 14:16:50 +08:00

56 lines
1.9 KiB
C

/* Generate random integers.
Copyright (C) 2006-2022 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
/* Written by Paul Eggert. */
#ifndef RANDINT_H
# define RANDINT_H 1
# include <stdint.h>
# include "randread.h"
/* An unsigned integer type, used for random integers, and its maximum
value. */
typedef uintmax_t randint;
# define RANDINT_MAX UINTMAX_MAX
struct randint_source;
void randint_free (struct randint_source *) _GL_ATTRIBUTE_NONNULL ();
int randint_all_free (struct randint_source *) _GL_ATTRIBUTE_NONNULL ();
struct randint_source *randint_new (struct randread_source *)
_GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_DEALLOC (randint_free, 1)
_GL_ATTRIBUTE_NONNULL () _GL_ATTRIBUTE_RETURNS_NONNULL;
struct randint_source *randint_all_new (char const *, size_t)
_GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_DEALLOC (randint_all_free, 1);
struct randread_source *randint_get_source (struct randint_source const *)
_GL_ATTRIBUTE_NONNULL () _GL_ATTRIBUTE_PURE;
randint randint_genmax (struct randint_source *, randint genmax)
_GL_ATTRIBUTE_NONNULL ();
/* Consume random data from *S to generate a random number in the range
0 .. CHOICES-1. CHOICES must be nonzero. */
static inline randint
randint_choose (struct randint_source *s, randint choices)
{
return randint_genmax (s, choices - 1);
}
#endif