8dd660ecd4
David S. Alessio has submitted the ICL and we can migrate the licenses to Apache. Gregory Nutt has submitted the SGA and we can migrate the licenses to Apache. Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
95 lines
3 KiB
C
95 lines
3 KiB
C
/****************************************************************************
|
|
* include/nuttx/lib/xorshift128.h
|
|
*
|
|
* Licensed to the Apache Software Foundation (ASF) under one or more
|
|
* contributor license agreements. See the NOTICE file distributed with
|
|
* this work for additional information regarding copyright ownership. The
|
|
* ASF licenses this file to you under the Apache License, Version 2.0 (the
|
|
* "License"); you may not use this file except in compliance with the
|
|
* License. You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
* License for the specific language governing permissions and limitations
|
|
* under the License.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/* This random number generator is simple, fast and portable.
|
|
* Ref: https://en.wikipedia.org/wiki/Xorshift
|
|
*/
|
|
|
|
#ifndef __INCLUDE_NUTTX_LIB_XORSHIFT128_H
|
|
#define __INCLUDE_NUTTX_LIB_XORSHIFT128_H
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <nuttx/config.h>
|
|
|
|
/****************************************************************************
|
|
* Pre-processor Definitions
|
|
****************************************************************************/
|
|
|
|
/* Default XorShift128 state initializer */
|
|
|
|
#define XORSHIFT128_INITIALIZER { 97, 101, 97 << 17, 101 << 25 }
|
|
|
|
/****************************************************************************
|
|
* Public Types
|
|
****************************************************************************/
|
|
|
|
/* Provides the state of the XorShift128 PRNG */
|
|
|
|
struct xorshift128_state_s
|
|
{
|
|
uint32_t x;
|
|
uint32_t y;
|
|
uint32_t z;
|
|
uint32_t w;
|
|
};
|
|
|
|
/****************************************************************************
|
|
* Public Function Prototypes
|
|
****************************************************************************/
|
|
|
|
#ifdef __cplusplus
|
|
#define EXTERN extern "C"
|
|
extern "C"
|
|
{
|
|
#else
|
|
#define EXTERN extern
|
|
#endif
|
|
|
|
/****************************************************************************
|
|
* Name: xorshift128
|
|
*
|
|
* Description:
|
|
* Generate one 32-bit pseudo-random number.
|
|
*
|
|
* NOTE: Because the PRNG state is passed as a parameter, this function is
|
|
* fully re-entrant and may be called from an interrupt handler.
|
|
*
|
|
* The downside to this is that users of the PRNG might not get as much
|
|
* entropy as if it were a common state structure.
|
|
*
|
|
* Input Parameters:
|
|
* state - The current XorShift128 state.
|
|
*
|
|
* Returned Value:
|
|
* The generated pseudo-random number
|
|
*
|
|
****************************************************************************/
|
|
|
|
uint32_t xorshift128(FAR struct xorshift128_state_s *state);
|
|
|
|
#undef EXTERN
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* __INCLUDE_NUTTX_LIB_XORSHIFT128_H */
|