mirror of https://github.com/dirtbags/moth.git
56 lines
1.6 KiB
C
56 lines
1.6 KiB
C
|
/*
|
||
|
|
------------------------------------------------------------------------------
|
||
|
|
rand.h: definitions for a random number generator
|
||
|
|
By Bob Jenkins, 1996, Public Domain
|
||
|
|
MODIFIED:
|
||
|
|
960327: Creation (addition of randinit, really)
|
||
|
|
970719: use context, not global variables, for internal state
|
||
|
|
980324: renamed seed to flag
|
||
|
|
980605: recommend RANDSIZL=4 for noncryptography.
|
||
|
|
010626: note this is public domain
|
||
|
|
101005: update to C99 (neale@lanl.gov)
|
||
|
|
------------------------------------------------------------------------------
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef __ISAAC_H__
|
||
|
|
#define __ISAAC_H__
|
||
|
|
|
||
|
|
#include <stdint.h>
|
||
|
|
|
||
|
|
#define RANDSIZL (8)
|
||
|
|
#define RANDSIZ (1<<RANDSIZL)
|
||
|
|
|
||
|
|
/* context of random number generator */
|
||
|
|
struct randctx {
|
||
|
|
uint32_t randcnt;
|
||
|
|
uint32_t randrsl[RANDSIZ];
|
||
|
|
uint32_t randmem[RANDSIZ];
|
||
|
|
uint32_t randa;
|
||
|
|
uint32_t randb;
|
||
|
|
uint32_t randc;
|
||
|
|
};
|
||
|
|
|
||
|
|
/*
|
||
|
|
------------------------------------------------------------------------------
|
||
|
|
If (flag==TRUE), then use the contents of randrsl[0..RANDSIZ-1] as the seed.
|
||
|
|
------------------------------------------------------------------------------
|
||
|
|
*/
|
||
|
|
void randinit(struct randctx *ctx, uint_fast8_t flag);
|
||
|
|
|
||
|
|
void isaac(struct randctx *ctx);
|
||
|
|
|
||
|
|
/*
|
||
|
|
------------------------------------------------------------------------------
|
||
|
|
Call rand(/o_ randctx *r _o/) to retrieve a single 32-bit random value
|
||
|
|
------------------------------------------------------------------------------
|
||
|
|
*/
|
||
|
|
#define rand32(r) \
|
||
|
|
(!(r)->randcnt-- ? \
|
||
|
|
(isaac(r), (r)->randcnt=RANDSIZ-1, (r)->randrsl[(r)->randcnt]) : \
|
||
|
|
(r)->randrsl[(r)->randcnt])
|
||
|
|
|
||
|
|
#endif /* RAND */
|
||
|
|
|
||
|
|
|
||
|
|
#endif /* __ISAAC_H__ */
|