dig-capsule 0.5.0

The DIG Network .dig capsule data plane — one crate over the DIGS format, capsule read-crypto, compiler, staging, and the guest/host serve triad.
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//! Deterministic gear-based content-defined chunking (FastCDC line) for Digstore.
//!
//! # Design notes (documented deviations & decisions)
//! - The gear hash is HAND-ROLLED (not delegated to the `fastcdc` crate) so we
//!   retain byte-exact control over the gear table and boundary algorithm. This
//!   guarantees identical chunk boundaries across platforms and crate versions,
//!   which is required for content-addressed dedup (design §4.2; paper §8.1, §3
//!   CDC heritage). We borrow only the *approach* (a 256-entry gear table + the
//!   `(hash & mask) == 0` cut rule) from FastCDC, not its code.
//! - The gear table is GENERATED AT COMPILE TIME by a `const fn` SplitMix64
//!   stream and is therefore exactly 256 entries by construction — no
//!   hand-authored literals that could miscount or contain malformed hex.
//! - Boundaries use the FastCDC rule `(hash & mask) == 0`, bounded by
//!   `ChunkerConfig::min_size` (no cut below it) and `ChunkerConfig::max_size`
//!   (forced cut at it).

mod boundary;
mod chunk;
mod chunker;
mod config;
mod gear;

pub use chunk::{hash_data, Chunk};
pub use chunker::{chunk_slice, Chunker};
// `chunk_stream` reads from `std::io::Read`, so it is only available with `std`
// (the collapsed crate is no_std under `--no-default-features` / the guest-wasm build).
#[cfg(feature = "std")]
pub use chunker::chunk_stream;
pub use config::{default_config, mask_for_target};
pub use gear::GEAR_TABLE;

#[cfg(all(test, not(target_arch = "wasm32")))]
mod tests;