flatfs

Flat Filesystem

What is it?

A simple way to package a small number of files into a single flat memory area. Like CPIO. [no-std]

Why?

Same reason why CPIO exists. I needed a way to easily create read-only partitions in Rust in 2023, and could not find a suitable and lightweight way to do it, so I rolled my own.

Goals

• [no-std]
• pack a small (~1k) number of "files" into a single contiguous memory region
  • here a "file" is a pair of (&str, &[u8])
• unpack that memory region back into "files"
• expose the "files" as a rudimentary directory tree (readonly)
• the "unpacked" filesystem should be reasonably efficient (both memory and CPU)
• no panicking (other than on OOM)

Non goals

• neither packing nor unpacking are required to be especially fast
• ensuring that filenames are "canonical" in any sense is not a goal
  • for example, the user may add a "/foo" file and a "/foo/bar" file, resulting in the root directory containing both a "foo" file and a "foo" directory