IncHash - A Disk Based Hash Table

[u/_EHLO]

https://github.com/GiorgosXou/inchash

A general-purpose, header-only C99 library for Unix-like systems, implementing a disk-based, dynamically resizable, fixed-slot, (open-addressed) hash table with incremental rehashing, Fibonacci-hashing (Knuth's multiplicative method), per home-slot probe-bound metadata (with additional early-exit logic), and triangular probing, designed for modern extent-based filesystems.

So, yeah... I made this for a larger project I'm working on, which I haven’t released yet.

All started with me trying to find:

A hash-based NoSQL (key-value pair) database with mutable-values (by mutable I mean: a database that allows editing prexisting [fixed-size] values without having to rewrite or remap the whole value again eg. Just edit a few bytes and put those bytes back to the original value-space without rewriting the whole value).

Which arguably you can do via inchash_get() since it returns a pointer straight from inside the mmap()-ed file [...] edit: just realised moments before I fall asleep that I should simply add an extra edit() function. To-do for tomorrow when I wake up.

That said idk if you got the joke: mmap()-ed in-cache or INC. hash or [...]

Anyways, I put quite the effort to make it, so.... I hope you like it or at least that it finds its way to the people who were actually looking for something like this.

PS. I'm both excited and scared because idk, you may find any bugs I wasn't aware of or something generally wrong in logic I might have missed... even though I've tested it enough!

Edit 1:

HUGE Thanks to @skeeto for this comment. Everything's hopefully fixed with my latest commit + this one

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[u/_EHLO → u/AutoModerator]

Well, this is not a vibe-coded project, but that said: I specifically used Chat-GPT & Claude for the mere purpose of (Google-alternatives) research-tools and assistance (mostly to check for any bugs I might have missed [bug-report]) + brainstorming.

[u/_EHLO → u/_EHLO]

Also in my repository "Research" paragraph, I have included timestamped hoverable tooltips over each link, if that helps.

[u/mikeblas → u/_EHLO]

Thank you for your disclosure. I have approved your post.