osobhandClaude Opus 5.5
052098bf36
Every `*_in` core and the read helpers take `file: &S` with `S: Storage + ?Sized` instead of `&dyn Storage`, and the `&[u8]` wrappers pass the slice itself, so they compile to a `[u8]` instance: `as_contiguous()` inlines to `Some(self)` and each structure read is the slice code's bounds check again, with no indirect call. `&dyn Storage` still works (`S = dyn Storage`); there is one parser implementation. Also, so the structure reads cost no more than the slice checks did: - ObjectHeader::parse_in reads the prefix once (signature included) instead of the signature and then the prefix: two reads for a one-chunk header instead of three on a range backend; - the symbol-table node and group B-tree (v1) loops walk their entries with chunks_exact over the bytes read, and the node's redundant second bounds check is gone (the entries' read is the check, same error); - a version-1 header's message list is sized from its (capped) count. Same results and errors; the unit and equivalence tests are unchanged. New Criterion bench `clawhdf5/benches/local_metadata_bench.rs` over a 400-group version-1 file written by h5py (new fixture `v1_groups_400.h5`): ObjectHeader::parse, symbol-table nodes, the group B-tree walk and a facade listing, using only APIs that exist atf2ff2c4so it builds there for an A/B. Provisional A/B againstf2ff2c4(busy machine, not for docs): both builds linked into one binary and timed in alternation, 200 rounds; median ratio new/old: facade listing -0.5% to -3.5% (was +14%), ObjectHeader::parse +1% to +2% (was +25%), symbol-table nodes -18%, group B-tree walk -18%, local-heap names and resolve_group_children within +-1.5%. An old-vs-old-copy run shows +-2% from code layout alone. Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
clawhdf5-format
Pure-Rust HDF5 binary format parsing and writing — no C dependencies.
Features
- Zero-copy superblock, object header, and B-tree parsing
- Chunked dataset read/write with filter pipelines
no_stdsupport (disablestdfeature)- Optional parallel reads via Rayon
- SHA-256 provenance tracking
Usage
use clawhdf5_format::Superblock;
let data = std::fs::read("data.h5").unwrap();
let sb = Superblock::from_bytes(&data).unwrap();
println!("HDF5 version {}.{}", sb.version_major(), sb.version_minor());
License
MIT