xxHash in pure Bash (with m4)
As the title says, this is a pure Bash implementation of XXH32 and XXH64 (m4 is used to expand macros, nothing else).
This code is a joke/proof of concept. The performance is terrible, and you are better with any other implementation. XXH64 runs about 150 times slower than the native implementation, and XXH32 runs about 250 times slower than the native implementation.
If you use this in production code, you are a monster.
The original xxHash code can be found at https://github.com/Cyan4973/xxhash, and you are 150-250 times better off using that implementaion.
Requirements: A Bash with 64-bit arithmetic (preferably a recent version, although macOS's bash 3.2 works), and m4 for building.
xxhsum.sh requires hexdump.
Usage: Don't.
Ok, this is how you use it:
./xxhsum.sh [-H0|-H1] [FILES...] (defaults to xxhash.sh)
-H0: XXH32, -H1: XXH64 (default)
. xxhash.sh
XXH32 "file in hex, no spaces or prefix" "seed"
XXH64 "file in hex, no spaces or prefix" "seed"
xxHash Library
Copyright (c) 2012-2016, Yann Collet
Copyright (c) 2019, easyaspi314
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