fal-rs, a filesystem abstraction layer

Allows backends (like ext2, apfs, btrfs, xfs etc.) to communicate with the frontends (currently including only FUSE and Redox), by implementing the Filesystem and FilesystemMut traits.

Features implemented

Backends

• ext2/ext3/ext4: Read-only (+writing metadata, but I haven’t checked if this actually works in a while). Ext2 filesystems can be read in quite an error-free way, whereas ext4 should be mostly working.
• apfs: Read-only (everything isn’t implemented to fully cover the limited spec provided by Apple, however reading files and listing directories is implemented)
• btrfs: WIP (reading B-trees is implemented, and probably error-free)
• xfs: TODO
• f2fs: TODO

Frontends

• FUSE: Read-only access to files and directories, including metadata.
• Redox: Same as FUSE.
• Linux kernel modules: TODO
• macOS kexts: TODO

TODO

• Create/use a proper parsing library. scroll is currently used in fal-backend-ext4, but some structs need manual parsing.
• Optimizations
• Testing, which requires either storing binary fs images in the repo, or depending on the system’s mkfs. There is a limited test suite, but it has to be expanded and improved.

License

Licensed under either of

• Apache License, Version 2.0
  (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license
  (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.