Every raw-data path has a generic *_in core, with the &[u8] functions as
thin wrappers: data_read (read_raw_data*, read_raw_data_selection,
read_chunked_native), chunked_read (the v1 B-tree chunk index, list_chunks,
the full, cached, sweep and indexed reads), parallel_read, partial_read,
fill_value (read_full_with_fill, apply_to_unallocated_chunks; and
dataset_fill_value_from_storage is now generic), vds (the virtual file
through Storage, external sources still through the resolver),
vl_data (VlResolver<'a, S = [u8]>, read_vl_strings_in, read_vl_bytes_in),
AttributeMessage::read_vl_strings_in and provenance::verify_dataset_in.
With the whole file in memory nothing changes: chunks and contiguous data
are sliced from it as before. Otherwise a chunked read lists its chunks,
fetches their stored bytes with one Storage::read_ranges call per 64 MiB
batch (chunks the cache already holds are not fetched), then decodes as
today; a selection fetches only the chunks it overlaps, and a contiguous
selection only its runs. Each extent's bounds error is the one the slice
code gave, reported when that extent is reached, so errors keep their
order.
Tests: the equivalence harness now reads every dataset's values (whole,
fill-aware, cached, indexed, three selections, VDS, VL strings and
sequences) through the read_at-only storage and requires the slice
results (all 653 corpus files agree); a misbehaving storage (a failing
Nth read, short reads) only ever yields errors or the right values; and
chunked reads are checked to use one read_ranges call.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
BTreeV2Header::parse_in, collect_btree_v2_records_in and
find_btree_v2_records_in read one bounded window per node (its size is
known from the parent before the node is read; a count stretched past
node_size is checked against the end of the file first), with the
whole-file bounds errors unchanged. With them, dense attributes, a SOHM
B-tree index and huge fractal-heap objects no longer answer
ContiguousStorageRequired, and group_v1/group_v2 listings, lookups and
path resolution get *_in cores (resolve_group_children_in,
resolve_child_in, resolve_path_any_in, ...). The &[u8] functions are
thin wrappers, as in M1.
The equivalence harness now fails on any ContiguousStorageRequired and
compares v2 B-tree headers, records and descents, group listings, child
lookups and paths; a unit test compares a two-level tree through a
read_at-only storage truncated at every length and with every node byte
flipped.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
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 at f2ff2c4
so it builds there for an A/B.
Provisional A/B against f2ff2c4 (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]>
Finding one link or attribute by name read every entry: Group::dataset and
Group::group (File, MmapFile, LazyFile) listed the whole group per call, and
path resolution scanned each group's links. Opening every child of a
35 001-link group by name decoded ~1.2e9 links.
Now a dense group's v2 B-tree name index (type 5, lookup3 hash of the
name) is descended to the records with the name's hash
(btree_v2::find_btree_v2_records reads only the nodes whose key interval
overlaps), and only those links are read and compared; all hash-equal
records are compared, so libhdf5's tie order does not matter. Dense
attributes the same through their type 8 index
(attribute::find_attribute_in_file, facade attr(name)); huge heap objects
through their ID-ordered index. group_v2::resolve_child returns what the
listing has under a name (soft links followed, dangling/external ones not
found). Group::entries and File::group_at hand out a listing's addresses.
The lookup-stats feature counts heap objects read. Tests: one lookup in
an h5py-written 35 001-link group with colliding hashes reads at most two
links (before: 35 001, failing), attribute lookups likewise (before: 3 000,
failing), every child opens through all three readers and matches h5py,
every link kind resolves as h5py resolves it in dense and compact groups,
300 huge attributes are found, and a range search matches a full scan at
every tree depth.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
AttributeMessage::parse_in_storage, extract_attributes_full_in and
extract_attributes_tolerant_in take the file as &dyn Storage: shared
datatypes, dataspaces and attributes are resolved through the Storage
shared-message path, and dense attributes' fractal heap through
FractalHeapHeader::parse_in / read_managed_object_in. The dense-storage
name index is a v2 B-tree, which is not read over Storage yet: over a
backend without the whole file in memory it is a clean
ContiguousStorageRequired error, never a partial list. The &[u8]
functions are wrappers.
New test: every object in five h5py-written fixtures (compact, shared
and dense attributes) reads identically through a slice as Storage, and
through a read_at-only CountingStorage except the dense ones, which give
the clean error.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
h5py's track_order=True orders attributes as well as links; the writer
tracked links only. A tracking object's header now sets the attribute
creation order tracked/indexed flags and carries per-message creation
orders, an Attribute Info message holds the next order (inline too),
and dense storage gets a type-9 creation-order index. The file default
applies to datasets, with DatasetBuilder::track_order per dataset; more
than 65 535 attributes on a tracking object is an error (libhdf5's
counter is 2 bytes). The reader lists such attributes in creation
order.
h5py lists them in order (inline, dense, 20 000 on one dataset) and
keeps numbering in r+ mode, including its inline-to-dense move.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
libhdf5 1.14.4+ treats an integer, float or bit field wider than a byte
whose precision and offset leave more than half its bits unused as
corruption when the type sits in a header without a checksum (version 1),
unless the file is opened with H5Pset_relax_file_integrity_checks
(H5T_is_numeric_with_unusual_unused_bits). clawhdf5 read such types,
e.g. a 3-bit integer in 4 bytes (cve-2024-29162) or a 32-bit float in
65525 bytes (cve-2024-32614, tmisc38a.h5).
New Datatype::check_unused_bits (recursive) and Datatype::parse_in_header,
which applies it for version-1 headers. Dataset datatypes (facade File,
LazyFile, MmapFile; clawhdf5-io VOL, MPI VOL, async reader; the
conformance probe) and compact attributes in version-1 headers use it.
Conformance (cached corpus, tank): 570 ok, unchanged; cve-2024-29162,
cve-2024-32614 and tmisc38a.h5 now refuse the object h5py refuses, and
tmisc38b.h5 / unknown-1.h5 now fail with libhdf5's reason.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Datatype::parse now makes the checks of libhdf5's H5O__dtype_decode_helper
and fails with InvalidDatatype (libhdf5's own error text) instead of
decoding a corrupt type:
- size 0 ("invalid datatype size"), for every class;
- integer bit offset/precision outside the type, or precision 0;
- float sign/exponent/mantissa outside the type, empty, or overlapping;
normalization 3; bit 6 without bit 0 from version 3;
- compound with no members, a member outside the compound, a duplicate
name, or a member overlapping an earlier one;
- enum whose size differs from its base type's, or an empty member name;
- array of more than 32 dimensions or with a zero-sized one (v1 compound
array members now say so rather than InvalidDatatypeVersion);
- opaque tag length that is not a multiple of 8.
Bit 6 of a version-1/2 float's class bits used to be read as VAX order,
byte-swapping values; libhdf5 ignores it before version 3, and so does
this now.
Only checks HDF5 2.0 (h5py 3.16) makes are added: newer libhdf5 also
checks bit fields, the variable-length kind and array sizes, but h5py
opens files that fail those, so they are left out. Each check was
confirmed against h5py by corrupting a file it wrote.
The conformance probe now decodes committed datatypes, as h5py's f[name]
does. Conformance (cached corpus, tank): 570 ok, unchanged. Objects
libhdf5 refuses that clawhdf5 used to read: cve-2016-4332-mtime (/cmpnd),
cve-2017-17508, cve-2024-32616 (/type1), cve-2024-32618, cve-2026-34734,
bad_compound.h5 (/cmpnd, /dataset); eight more that already failed now
fail with libhdf5's reason (e.g. cve-2024-29163 "mantissa range out of
bounds").
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
attrs() read every attribute of an object through extract_attributes_full,
so one attribute it could not read (a corrupt or unsupported attribute
message, or a heap object it could not locate) failed all of them — the
same shape as the huge-object bug, where one 8 KiB attribute hid every
attribute on a NetCDF file's root group.
- clawhdf5-format: new attribute::extract_attributes_tolerant returns the
attributes it could read plus one error per attribute it could not.
Errors in the attribute index itself (Attribute Info message, dense
heap header, B-tree) still fail, since then it is unknown which
attributes exist. extract_attributes_full is unchanged (strict); both
share one implementation.
- clawhdf5: attrs() on Group/Dataset, MmapGroup/MmapDataset and
LazyGroup/LazyDataset leaves an unreadable attribute out (documented),
and the new attrs_with_errors() returns the map with the per-attribute
errors. A value is either returned complete or not at all.
Regression test: one_unreadable_attribute_does_not_hide_the_others (h5py
writes 11 dense attributes; one message's version byte is corrupted;
before: attrs() failed with InvalidAttributeVersion(127), after: the 10
others come back with their values and one error is reported).
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
A version-1 shared message reference is version, type, six reserved bytes
and then an old-style symbol table entry: link-name offset (length size),
object header address, cache type, reserved, scratch. We read the address
straight after the reserved bytes, i.e. the link-name offset, and the
committed datatype lookup failed with InvalidObjectHeaderVersion (the bytes
checked in tcompound.h5: name offset 0x10, then 0x590 = /type1). Datasets
of 1.4/1.6-era files that use a committed datatype were unreadable.
Skip the name offset. parse_shared_ref has no length size, so add
parse_shared_ref_sized and use it in every internal caller;
parse_shared_ref keeps its signature and assumes length size == offset
size. The old parse_v1_ref unit test encoded the wrong layout and now uses
the real bytes.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
A dataset created from a committed (named) datatype stores only a shared-
message reference to it. The facade parsed those reference bytes as the
datatype itself, producing `Time { size: 0 }` and unreadable data, and an
attribute using a committed datatype was silently dropped.
- shared_message::parse_shared_ref had the encoding wrong: it skipped six
reserved bytes for version 2 (only version 1 has them) and had the version 3
types inverted (1 is the SOHM heap, 2 is "committed, in another object
header"). Verified against h5py 3.16 / HDF5 2.0, which writes
`02 02 <address>` under both default and latest libver bounds. Resolution
now dispatches on which field the reference carries.
- New shared_message::message_data resolves a header message through the
indirection; the reader, lazy and mmap facades use it for datatype,
dataspace and filter-pipeline messages.
- AttributeMessage honours the v2/v3 flags (bit 0 datatype shared, bit 1
dataspace shared) via the new parse_in_file, used everywhere file data is
available. Parsing a shared attribute without file access is now
FormatError::UnresolvedSharedMessage instead of a garbage datatype.
- h5py interop test covering both libver settings.
Co-Authored-By: Claude Fable 5.1 <[email protected]>
- clippy --all-targets plus a clawhdf5-format feature matrix (parallel, lz4,
zstd, pcodec, fast-checksum); fix the accumulated lint backlog in test,
bench and feature-gated code (no behaviour changes).
- Install python3 + h5py/numpy/netCDF4/xarray in the CI container and set
CLAWHDF5_REQUIRE_INTEROP=1, which makes a missing interop dependency a test
failure. Every h5py/netCDF4 interop test used to skip silently in CI. Run
the #[ignore]d writer_h5py_tests suite explicitly.
- cargo bench --no-run so benches can't rot; fix bench.rs and memory_bench.rs,
which no longer compiled against the current strategy/consolidation APIs.
- Optional fuzz smoke run via CLAWHDF5_FUZZ_SECONDS.
- CHANGELOG and docs/known-issues.md updated.
Co-Authored-By: Claude Fable 5.1 <[email protected]>