| 1 | #ifndef FIO_RAND_H |
| 2 | #define FIO_RAND_H |
| 3 | |
| 4 | #define FRAND_MAX (-1U) |
| 5 | |
| 6 | struct frand_state { |
| 7 | unsigned int s1, s2, s3; |
| 8 | }; |
| 9 | |
| 10 | static inline void frand_copy(struct frand_state *dst, |
| 11 | struct frand_state *src) |
| 12 | { |
| 13 | dst->s1 = src->s1; |
| 14 | dst->s2 = src->s2; |
| 15 | dst->s3 = src->s3; |
| 16 | } |
| 17 | |
| 18 | static inline unsigned int __rand(struct frand_state *state) |
| 19 | { |
| 20 | #define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b) |
| 21 | |
| 22 | state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12); |
| 23 | state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4); |
| 24 | state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17); |
| 25 | |
| 26 | return (state->s1 ^ state->s2 ^ state->s3); |
| 27 | } |
| 28 | |
| 29 | extern void init_rand(struct frand_state *); |
| 30 | extern void init_rand_seed(struct frand_state *, unsigned int seed); |
| 31 | extern void __fill_random_buf(void *buf, unsigned int len, unsigned long seed); |
| 32 | extern unsigned long fill_random_buf(struct frand_state *, void *buf, unsigned int len); |
| 33 | extern unsigned long fill_random_buf_percentage(struct frand_state *, void *, unsigned int, unsigned int, unsigned int, char *, unsigned int); |
| 34 | extern void fill_pattern(void *p, unsigned int len, char *pattern, unsigned int pattern_bytes); |
| 35 | |
| 36 | #endif |