bitwise.go


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// SPDX-License-Identifier: BSD-2-Clause
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package main

func validateBitZeros(bs []byte, n uint) bool {
	q := n / 8
	r := n % 8

	for i := uint(0); i < q; i++ {
		if bs[i] != 0 {
			return false
		}
	}

	if r > 0 {
		mask := byte(0xFF << (8 - r))
		if bs[q]&mask != 0 {
			return false
		}
	}

	return true
}