osobhandClaude Opus 5.5
b4a44a2e66
Unlimited VDS mappings were refused, and printf-style source names
("f-%b.h5") were not expanded, so those regions read as fill (read-matrix
case 0470: 29 of 30 values wrong). All 7 virtual datasets in the libhdf5
test set use such mappings.
Implement H5Dvirtual.c's semantics in the vds module:
- %b is the block number, %% a literal %, other specifiers are an error;
block j of the virtual selection comes from the source named with j,
probing from 0 to the first missing source (printf gap 0);
- unlimited source/virtual selections are clipped to what the source's
current extent fills (H5S_hyper_get_clip_extent_match, partial last
block included);
- the extent is recomputed as H5Dget_space does (view "last available":
the largest clip, never below what limited mappings need), exposed as
vds::virtual_dataset_extent and used by Dataset::shape();
- a source in the other byte order is byte-swapped; other conversions stay
an error.
Tests: vds_interop::vds_printf_source_names,
vds_unlimited_mappings_follow_source_extents (h5py low-level API, earliest
and latest format) and vds_libhdf5_test_files (vds-eiger, 4_vds and
vds-percival-unlim-maxmin from HDF5's tools/test/testfiles/vds, committed
as fixtures) all compare shape and values with h5py; unit tests for the
clip arithmetic, name parsing and mapping rules.
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