preflate-rs 0.7.0

Decompresses existing DEFLATE streams to allow for better compression (eg with ZStandard) while allowing the exact original binary DEFLATE stream to be recreated by detecting the parameters used during compression.
Documentation 
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/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the Apache License, Version 2.0. See LICENSE.txt in the project root for license information.
 *  This software incorporates material from third parties. See NOTICE.txt for details.
 *--------------------------------------------------------------------------------------------*/

pub fn bit_length(n: u32) -> u32 {
    32 - n.leading_zeros()
}

#[derive(Copy, Clone, Debug, Eq, PartialEq, Default)]
pub struct DebugHash {
    hash: u64,
}

#[allow(dead_code)]
impl DebugHash {
    pub fn update<T: Into<i64>>(&mut self, v: T) {
        self.hash = self.hash.wrapping_mul(13).wrapping_add(v.into() as u64);
    }

    pub fn update_slice<T: Into<i64> + Copy>(&mut self, v: &[T]) {
        v.iter().for_each(|x| self.update(*x));
    }

    pub fn hash(&self) -> u64 {
        self.hash
    }
}