# Adler-32 checksums for RustThis is a fork of the adler crate as the [original](https://github.com/jonas-schievink/adler) has been archived and is no longer updated by it's author

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This crate provides a simple implementation of the Adler-32 checksum, used inthe zlib compression format.Please refer to the [changelog](CHANGELOG.md) to see what changed in the lastreleases.## Features- Permissively licensed (0BSD) clean-room implementation.- Zero dependencies.- Zero `unsafe`.- Decent performance (3-4 GB/s) (see note).- Supports `#![no_std]` (with `default-features = false`).## UsageAdd an entry to your `Cargo.toml`:```toml[dependencies]adler2 = "2.0.0"```Check the [API Documentation](https://docs.rs/adler/) for how to use thecrate's functionality.## Rust version supportCurrently, this crate supports all Rust versions starting at Rust 1.56.0.Bumping the Minimum Supported Rust Version (MSRV) is *not* considered a breakingchange, but will not be done without good reasons. The latest 3 stable Rustversions will always be supported no matter what.## PerformanceDue to the way the algorithm works this crate and the fact that it's not possible to use explicit simd in safe rust currently, this crate benefits drastically from being compiled with newer cpu instructions enabled (using e.g  ```RUSTFLAGS=-C target-feature'+sse4.1``` or ```-C target-cpu=x86-64-v2```/```-C target-cpu=x86-64-v3``` arguments depending on what cpu support is being targeted.)Judging by the crate benchmarks, on a Ryzen 5600, compiling with SSE 4.1 (enabled in x86-64-v2 feature level) enabled can give a ~50-150% speedup, enabling the LZCNT instruction (enabled in x86-64-v3 feature level) can give a further ~50% speedup,