diff options
Diffstat (limited to 'xorshift.c')
| -rw-r--r-- | xorshift.c | 11 |
1 files changed, 6 insertions, 5 deletions
@@ -7,6 +7,7 @@ #include <assert.h> #include <limits.h> #include <sys/random.h> +#include <math.h> #include <string.h> #include "structs.h" @@ -16,23 +17,23 @@ __attribute__((visibility("default"))) bool initialize_states(){ assert( (sizeof(uint32_t) * CHAR_BIT) == 32 ); memset( (void*)&global_rng_state, 0, sizeof(struct rng_state) ); ssize_t state_bytes_read = 0; - if ( (state_bytes_read = getrandom((void*)&global_rng_state.states, 16 * sizeof(uint32_t), GRND_NONBLOCK)) == -1 ) + if ( (state_bytes_read = getrandom((void*)&global_rng_state.states, STATE_SIZE * sizeof(uint32_t), GRND_NONBLOCK)) == -1 ) return false; - if ( (size_t)state_bytes_read < (16 * sizeof(uint32_t)) ){ + if ( (size_t)state_bytes_read < (STATE_SIZE * sizeof(uint32_t)) ){ errno = EIO; return false; } - global_rng_state.state_idx = global_rng_state.states[7] >> 28; + global_rng_state.state_idx = global_rng_state.states[(uint32_t)(floor(STATE_SIZE / 2))] >> SHIFT_VALUE; errno = 0; return true; } __attribute__((visibility("default"))) uint32_t get_random_output(){ size_t use_state = global_rng_state.state_idx; - global_rng_state.state_idx = global_rng_state.states[use_state] >> 28; + global_rng_state.state_idx = global_rng_state.states[use_state] >> SHIFT_VALUE; if ( global_rng_state.gen_period_ctr >= 0xffffffff ){ global_rng_state.period_end_ctr++; - if ( global_rng_state.period_end_ctr >= 16 ){ + if ( global_rng_state.period_end_ctr >= STATE_SIZE ){ assert( initialize_states() == true ); global_rng_state.period_end_ctr = 0; } |