Crate lambutter 

no_std read-only btrfs reader for UEFI bootloaders and embedded contexts.

Lambutter is the btrfs counterpart to ext4-view: a pure-Rust, allocation-aware, read-only btrfs filesystem reader for contexts that cannot link std. It opens regular files, symlinks, and directory listings on SINGLE / DUP / RAID1 / RAID1C3 / RAID1C4 volumes and decodes zstd, zlib, and LZO extents; unsupported profiles surface as typed errors.

See the README for scope, validation posture, and usage; CHANGELOG.md for the version history.

Structs

Btrfs

A mounted, read-only btrfs filesystem.

DirEntry

One directory entry, owned (its name is copied so the iterator doesn’t hold a borrow on the underlying tree block).

Inode

An inode within the active subvolume. Currently a thin newtype wrapping the inode objectid; future versions may carry cached metadata.

Metadata

Metadata accessor — analogous to std::fs::Metadata for callers.

Path

A read-only path into the active subvolume. Paths are absolute (must start with /); leading / segments collapse, internal // collapses to /, and . components are skipped.

Enums

Error

All error conditions the crate can surface to its caller.

SliceReadError

Error variants for the &[u8] adapter. Test/diagnostic only.

SuperblockReason

Why the superblock was rejected. Present as a sub-enum so callers that only care about the boundary can match on Error::BadSuperblock(_) without enumerating the inner variants.

Traits

BlockRead

A read-only block-level reader.

Type Aliases

Result

Crate-wide result alias.