osobhandClaude Opus 5.5
bd1d8f1a59
The link and attribute name indexes are one v2 B-tree leaf, sized to the
next power of two. libhdf5 takes a leaf's capacity from that node size,
but a leaf's record count is a 2-byte field. From about 47 700 links the
node had room for more than 65 535 records, so adding a link in h5py
overflowed the count: a group of 65 535 links crashed h5py, or could no
longer be listed ("unknown link class"). The node is now capped at a full
leaf of 65 535 records, so libhdf5 splits it instead.
Dense attributes now go through the same index builder. Their record
count was written modulo 65 536, without error; more than 65 535
attributes on one object are now refused, like links.
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