mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-08 22:30:07 +00:00
688903eb3e
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
49 lines
1.4 KiB
C
49 lines
1.4 KiB
C
/* Reentrant random function from POSIX.1c.
|
|
Copyright (C) 1996-2018 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <stdlib.h>
|
|
|
|
|
|
/* This algorithm is mentioned in the ISO C standard, here extended
|
|
for 32 bits. */
|
|
int
|
|
rand_r (unsigned int *seed)
|
|
{
|
|
unsigned int next = *seed;
|
|
int result;
|
|
|
|
next *= 1103515245;
|
|
next += 12345;
|
|
result = (unsigned int) (next / 65536) % 2048;
|
|
|
|
next *= 1103515245;
|
|
next += 12345;
|
|
result <<= 10;
|
|
result ^= (unsigned int) (next / 65536) % 1024;
|
|
|
|
next *= 1103515245;
|
|
next += 12345;
|
|
result <<= 10;
|
|
result ^= (unsigned int) (next / 65536) % 1024;
|
|
|
|
*seed = next;
|
|
|
|
return result;
|
|
}
|