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-rw-r--r--v_windows/v/vlib/rand/seed/seed.v40
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
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+++ b/v_windows/v/vlib/rand/seed/seed.v
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+// 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)
+}