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// Copyright (c) 2019-2024 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 rand
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#flag windows -Llibraries/bcrypt
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#flag windows -lbcrypt
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#include <bcrypt.h>
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const status_success = 0x00000000
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const bcrypt_use_system_preferred_rng = 0x00000002
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// read returns an array of `bytes_needed` random bytes read from the OS.
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pub fn read(bytes_needed int) ![]u8 {
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	mut buffer := []u8{len: bytes_needed}
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	// use bcrypt_use_system_preferred_rng because we passed null as algo
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	status := C.BCryptGenRandom(0, buffer.data, bytes_needed, bcrypt_use_system_preferred_rng)
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	if status != status_success {
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		return &ReadError{}
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	}
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	return buffer
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}
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