/*
* Copyright (c) 2020 Red Hat, 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 2
* 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* $Id: //eng/uds-releases/jasper/src/uds/random.h#2 $
*/
#ifndef RANDOM_H
#define RANDOM_H
#ifdef __KERNEL__
#include <linux/random.h>
#else
#include <stdlib.h>
#endif
#include "compiler.h"
#include "typeDefs.h"
/**
* Get random unsigned integer in a given range
*
* @param lo Minimum unsigned integer value
* @param hi Maximum unsigned integer value
*
* @return unsigned integer in the interval [lo,hi]
**/
unsigned int randomInRange(unsigned int lo, unsigned int hi);
/**
* Special function wrapper required for compile-time assertions. This
* function will fail to compile if RAND_MAX is not of the form 2^n - 1.
**/
void randomCompileTimeAssertions(void);
/**
* Fill bytes with random data.
*
* @param ptr where to store bytes
* @param len number of bytes to write
**/
#ifdef __KERNEL__
static INLINE void fillRandomly(void *ptr, size_t len)
{
prandom_bytes(ptr, len);
}
#else
void fillRandomly(void *ptr, size_t len);
#endif
#ifdef __KERNEL__
#define RAND_MAX 2147483647
/**
* Random number generator
*
* @return a random number in the rand 0 to RAND_MAX
**/
static INLINE long random(void)
{
long value;
fillRandomly(&value, sizeof(value));
return value & RAND_MAX;
}
#endif
#endif /* RANDOM_H */