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Diffstat (limited to 'v_windows/v/vlib/rand/seed/seed.v')
-rw-r--r-- | v_windows/v/vlib/rand/seed/seed.v | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/v_windows/v/vlib/rand/seed/seed.v b/v_windows/v/vlib/rand/seed/seed.v new file mode 100644 index 0000000..3b1ef7a --- /dev/null +++ b/v_windows/v/vlib/rand/seed/seed.v @@ -0,0 +1,40 @@ +// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved. +// Use of this source code is governed by an MIT license +// that can be found in the LICENSE file. +module seed + +import time + +// nr_next returns a next value based on the previous value `prev`. +[inline] +fn nr_next(prev u32) u32 { + return prev * 1664525 + 1013904223 +} + +// time_seed_array returns the required number of u32s generated from system time. +[inline] +pub fn time_seed_array(count int) []u32 { + ctime := time.sys_mono_now() + mut seed := u32(ctime >> 32 ^ (ctime & 0x0000_0000_FFFF_FFFF)) + mut seed_data := []u32{cap: count} + for _ in 0 .. count { + seed = nr_next(seed) + seed_data << nr_next(seed) + } + return seed_data +} + +// time_seed_32 returns a 32-bit seed generated from system time. +[inline] +pub fn time_seed_32() u32 { + return time_seed_array(1)[0] +} + +// time_seed_64 returns a 64-bit seed generated from system time. +[inline] +pub fn time_seed_64() u64 { + seed_data := time_seed_array(2) + lower := u64(seed_data[0]) + upper := u64(seed_data[1]) + return lower | (upper << 32) +} |