WIP formal spec for a version of the content-based splitting algorithms used by systems such as perkeep, bup, kopia, asuran, and others.
The spec is available in HTML and PDF formats.
Many systems use some version of this hash-splitting algorithm, but because they all compute slightly different splits, it's difficult to write interoperable tools around them.
The goal of this project is to provide a formal spec for a parametrized version of the algorithm, along with test suites, to facilitate building interoperable implementations. The idea is, a tool using hash splitting should be able to just say in its docs which hashsplit function it uses, just as tools which use cryptographic hashes can just say "sha256" or the like, and developers working in other languages with other libraries can easily make use of that information.
Install pandoc and type make.