osobhandClaude Fable 5.1
52cfcf20b2
HDF5 1.12 revised the reference datatype (class 7) in datatype message version 4: reference types 2-4 are the new H5T_STD_REF object / dataset-region / attribute references. Datatype::parse rejected them with InvalidReferenceType, so any dataset of that type was unreadable. h5py cannot write this type, which is why it had never been tested. A real file was produced by calling the libhdf5 bundled in the h5py wheel through ctypes (H5T_STD_REF_g, H5Rcreate_object, H5Dwrite); the 2 KB result is committed as tests/fixtures/std_ref_hdf5_2_0.h5 with its generator, gen_std_ref.py. - ReferenceType gains Object2, DatasetRegion2 and Attribute, accepted only from datatype version 4. - read_object_references decodes Object2 elements: type(1) flags(1) token_size(1) token, zero-padded to the element size; the token is the target's object header address. A null reference decodes to the undefined address; an external reference, a wrong type byte or a token that doesn't fit is an error. The fixture test follows both references and checks they resolve to the objects they were created from. Co-Authored-By: Claude Fable 5.1 <[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