From 9695ea005d4af93dcd60f74f10fd3c54499a182f Mon Sep 17 00:00:00 2001 From: Nicholas Noll Date: Thu, 11 Nov 2021 16:31:58 -0800 Subject: chore: split up base library into individual files for smaller binaries --- sys/base/rng/random.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 sys/base/rng/random.c (limited to 'sys/base/rng/random.c') diff --git a/sys/base/rng/random.c b/sys/base/rng/random.c new file mode 100644 index 0000000..bd1bd6b --- /dev/null +++ b/sys/base/rng/random.c @@ -0,0 +1,33 @@ +#include "internal.h" + +static uint64 +xoshiro256ss(Rng *state) +{ + uint64 *s = state->s; + uint64 result = rol64(s[1] * 5, 7) * 9; + uint64 t = s[1] << 17; + + s[2] ^= s[0]; + s[3] ^= s[1]; + s[1] ^= s[2]; + s[0] ^= s[3]; + + s[2] ^= t; + s[3] = rol64(s[3], 45); + + return result; +} + +double +rng·random(void) +{ + uint64 r = xoshiro256ss(&rng·RNG); + return (double)r / (double)UINT64_MAX; +} + +uint64 +rng·randi(int max) +{ + uint64 r = xoshiro256ss(&rng·RNG); + return r % max; +} -- cgit v1.2.1