bux-e2fs

Ext4 filesystem image creation via libext2fs — static FFI bindings and safe Rust API.

Note: This crate statically links libext2fs from e2fsprogs. For most use cases, prefer the high-level bux crate.

How it works

Pre-generated bindgen bindings are committed in src/bindings.rs so end users do not need libclang installed. At build time the build script:

1. Downloads pre-built static libraries from GitHub Releases (or uses BUX_E2FS_DIR).
2. Statically links libext2fs, libcom_err, libe2p, libuuid, and libcreate_inode.

Regenerating bindings

To update bindings from the pinned e2fsprogs headers (requires libclang, Linux/macOS only):

BUX_UPDATE_BINDINGS=1 cargo check -p bux-e2fs --features regenerate

Safe API

use bux_e2fs::Ext4Builder;
use std::path::Path;

// Create an ext4 image from a directory (like mke2fs -d)
Ext4Builder::new()
    .block_size(4096)
    .reserved_ratio(0)
    .create_from_dir(
        Path::new("/tmp/rootfs"),
        Path::new("/tmp/base.raw"),
        512 * 1024 * 1024,
    )?;

// Inject a file into an existing image (like debugfs write)
Ext4Builder::inject_file(
    Path::new("/tmp/base.raw"),
    Path::new("/usr/local/bin/bux-guest"),
    "usr/local/bin/bux-guest",
)?;

Environment variables

Supported platforms

License

Licensed under either of Apache License, Version 2.0 or MIT License at your option.