//! CUBELinux-2 Package 3 — `cubefs`: a POSIX namespace over CZYX.
//!
//! Built NEW from the PDF spec (Package 3, p. "cubefs (filesystem or virtual
//! FS)"). Not recycled from the prior `/home/CUBELinux` build, which had no
//! filesystem layer at all.
//!
//! # What the PDF asks for
//!
//! > Map C/Z/Y/X ranges to top-level directories (C), subdirs (Z,Y) and files
//! > (X), or keep the 4-D API but expose FUSE hooks for POSIX compatibility.
//! > Use Null cubes/rows for: ACLs, extended attributes, journaling, volume
//! > metadata.
//!
//! # Structure of this crate
//!
//! * [`path`] — the pure, dependency-free bijection between POSIX paths and
//!   [`Czyx`] coordinates. This is the part that must be provably correct, so
//!   it is testable without a kernel mount.
//! * [`nullspace`] — the Null-cube control plane: ACLs, xattrs, the journal,
//!   and volume metadata, each pinned to a documented `C=0` sub-cube.
//! * [`vfs`] — the backend-agnostic filesystem operations (lookup, readdir,
//!   read, write, getattr, xattr, ACL check) expressed over a [`CubeStore`].
//! * `fuse` (feature `mount`) — the thin adapter that translates kernel FUSE
//!   calls into [`vfs`] calls. Feature-gated so the logic above builds and
//!   tests anywhere.
//!
//! # Decision: why a bijection and not an inode table
//!
//! A conventional FUSE filesystem allocates opaque inode numbers and keeps a
//! side table mapping inode -> object. CUBELinux's whole premise is that the
//! coordinate *is* the address, so allocating a second, unrelated identifier
//! space would reintroduce exactly the indirection the design removes.
//! Instead the inode number IS the packed `u32` coordinate (widened to u64),
//! so `ino <-> Czyx` is total, stateless, and needs no table. The FUSE root
//! inode is required by the kernel to be 1, and `Czyx::unpack_u32(1)` is
//! `(0,0,0,1)` — a Null cube, never a user record — so the reservation costs
//! us no addressable user space. See [`path::ino_to_czyx`].

#![forbid(unsafe_code)]
#![warn(missing_docs)]

pub mod backend;
pub mod nullspace;
pub mod path;
pub mod vfs;

#[cfg(feature = "mount")]
pub mod fuse;

pub use backend::DaemonBackend;
pub use nullspace::{Acl, JournalEntry, JournalOp, NullSpace, VolumeMeta};
pub use path::{czyx_to_ino, ino_to_czyx, parse_path, render_path, PathError, ROOT_INO};
pub use vfs::{Attr, CubeFs, FsError, Kind};