45 lines
1.1 KiB
V
45 lines
1.1 KiB
V
// Copyright (c) 2019-2022 Alexander Medvednikov. All rights reserved.
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// Use of this source code is governed by an MIT license
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// that can be found in the LICENSE file.
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module seed
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import time
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// nr_next returns a next value based on the previous value `prev`.
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[inline]
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fn nr_next(prev u32) u32 {
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return prev * 1664525 + 1013904223
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}
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// time_seed_array returns the required number of u32s generated from system time.
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pub fn time_seed_array(count int) []u32 {
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ctime := time.sys_mono_now()
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mut seed := u32(ctime >> 32 ^ (ctime & 0x0000_0000_FFFF_FFFF))
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mut seed_data := []u32{cap: count}
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for _ in 0 .. count {
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seed = nr_next(seed)
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seed_data << nr_next(seed)
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}
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return seed_data
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}
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// time_seed_32 returns a 32-bit seed generated from system time.
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[manualfree]
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pub fn time_seed_32() u32 {
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sa := time_seed_array(1)
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res := sa[0]
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unsafe { sa.free() }
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return res
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}
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// time_seed_64 returns a 64-bit seed generated from system time.
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[manualfree]
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pub fn time_seed_64() u64 {
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seed_data := time_seed_array(2)
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lower := u64(seed_data[0])
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upper := u64(seed_data[1])
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unsafe { seed_data.free() }
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res := lower | (upper << 32)
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return res
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}
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