quantumclaw/clawhdf5
3
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases 1 Wiki Activity

writer: track attribute creation order with track_order

Browse Source 
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]>
This commit is contained in:
osobh
2026-09-26 10:17:37 -05:00
co-authored by Claude Opus 5.5
parent d63c76e7ab
commit 193a5f8a82
9 changed files with 515 additions and 101 deletions
Download Patch File Download Diff File Expand all files Collapse all files
docs/known-issues.md
+10 -2
View File
@@ -264,8 +264,16 @@ fill-value item that did is fixed).
external links at any depth and optional creation-order tracking;
h5py, h5dump and `h5rs check --data` read them
(`crates/clawhdf5/tests/writer_groups_interop.rs`,
`crates/clawhdf5-tools/tests/h5rs_interop.rs`). Still missing:
attribute creation order is not tracked.
`crates/clawhdf5-tools/tests/h5rs_interop.rs`). ~~Still missing:
attribute creation order is not tracked.~~ **Fixed 2026-09-26:**
`track_order` (file default, `GroupBuilder`, and the new
`DatasetBuilder::track_order`) tracks and indexes attribute creation
order as h5py's `track_order=True` does; h5py lists the attributes in
the order they were set, inline and dense (20 000 on one dataset), and
keeps numbering them in "r+" mode (tank,
`cargo test -p clawhdf5 --test writer_groups_interop
track_order_lists_attributes_in_creation_order`). libhdf5 numbers at
most 65 535 attributes on such an object, so more is an error.
- ~~A group with more than 65 535 links, or an object with more than
65 535 dense attributes, is an error (the index is one B-tree leaf).~~
**Fixed 2026-09-26:** the dense indexes are v2 B-trees of any depth