read: look names up through the dense name indexes

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]>
This commit is contained in:
osobh
2026-09-26 13:33:19 -05:00
co-authored by Claude Opus 5.5
parent 6248b411f0
commit 02e89c1d2d
15 changed files with 1245 additions and 159 deletions
+3
View File
@@ -80,6 +80,9 @@ blosc = ["lz4_flex", "ruzstd", "snap", "deflate", "std"]
blosc2 = ["blosc"]
# Every plugin filter above.
plugin-filters = ["lzf", "bitshuffle", "bzip2", "blosc", "blosc2"]
# Test instrumentation: per-thread counts of heap objects read (see
# `lookup_stats`), so tests can bound the cost of a name lookup.
lookup-stats = ["std"]
[[bench]]
name = "parallel_decompress_bench"
+148 -33
View File
@@ -5,8 +5,10 @@ use alloc::{borrow::Cow, string::String, vec::Vec};
#[cfg(feature = "std")]
use std::borrow::Cow;
use crate::addr::to_usize;
use crate::attribute_info::AttributeInfoMessage;
use crate::btree_v2::{BTreeV2Header, collect_btree_v2_records};
use crate::btree_v2::{BTreeV2Header, collect_btree_v2_records, find_btree_v2_records};
use crate::checksum::jenkins_lookup3;
use crate::data_read;
use crate::dataspace::Dataspace;
use crate::datatype::Datatype;
@@ -341,7 +343,8 @@ fn compute_raw_data(
dataspace: &Dataspace,
datatype: &Datatype,
) -> Vec<u8> {
let num_elements = dataspace.num_elements() as usize;
// Saturating, like the product: the size is capped at what is there.
let num_elements = usize::try_from(dataspace.num_elements()).unwrap_or(usize::MAX);
let elem_size = datatype.type_size() as usize;
let expected_size = num_elements.saturating_mul(elem_size);
let available = data.len().saturating_sub(pos);
@@ -453,7 +456,145 @@ fn extract_attributes_with(
// Each attribute's creation order, where the file records one.
let mut orders: Vec<u32> = Vec::new();
// Collect compact attributes (inline in OH)
extract_compact_attributes(
file_data,
header,
offset_size,
length_size,
&mut attrs,
&mut orders,
on_error,
)?;
// Check for dense attributes via AttributeInfo message
let attr_info = find_attribute_info(header, offset_size)?;
if let Some(info) = &attr_info
&& let Some(fh_addr) = info.fractal_heap_address
{
extract_dense_attributes(
file_data,
info,
fh_addr,
offset_size,
length_size,
&mut attrs,
&mut orders,
on_error,
)?;
}
// An object that tracks attribute creation order lists its attributes
// in that order (h5py's `track_order=True`), as libhdf5 does; otherwise
// they come in storage order.
if attr_info.is_some_and(|i| i.max_creation_index.is_some()) {
let mut paired: Vec<(u32, AttributeMessage)> = orders.into_iter().zip(attrs).collect();
paired.sort_by_key(|(o, _)| *o);
attrs = paired.into_iter().map(|(_, a)| a).collect();
}
Ok(attrs)
}
/// B-tree v2 record type of dense attribute storage's name index.
const ATTRIBUTE_NAME_INDEX: u8 = 8;
/// The attribute called `name` on the object with header `header`: the
/// first one [`extract_attributes_tolerant`] returns under that name, or
/// `None` if it returns none (an attribute that cannot be read is not
/// returned there either).
///
/// Compact attributes are in the header and are scanned. Dense attributes
/// are found through the name index (a v2 B-tree of lookup3 name hashes,
/// record type 8): only the attributes whose names hash like `name` are read
/// from the heap, O(log n) instead of all of them. Errors in the structures
/// that index the attributes fail the call, as they fail a listing.
pub fn find_attribute_in_file(
file_data: &[u8],
header: &ObjectHeader,
name: &str,
offset_size: u8,
length_size: u8,
) -> Result<Option<AttributeMessage>, FormatError> {
let attr_info = find_attribute_info(header, offset_size)?;
let dense = attr_info
.as_ref()
.and_then(|i| Some((i.fractal_heap_address?, i.btree_name_index_address?)));
let Some((fh_addr, btree_addr)) = dense else {
// Compact only (or dense storage without a name index, which a
// listing reports): as a listing finds it.
return Ok(
extract_attributes_tolerant(file_data, header, offset_size, length_size)?
.0
.into_iter()
.find(|a| a.name == name),
);
};
let btree_hdr =
BTreeV2Header::parse(file_data, to_usize(btree_addr)?, offset_size, length_size)?;
let fh = FractalHeapHeader::parse(file_data, to_usize(fh_addr)?, offset_size, length_size)?;
if btree_hdr.tree_type != ATTRIBUTE_NAME_INDEX || btree_hdr.record_size < 4 {
return Ok(
extract_attributes_tolerant(file_data, header, offset_size, length_size)?
.0
.into_iter()
.find(|a| a.name == name),
);
}
// A listing has the compact attributes first.
let mut compact = Vec::new();
extract_compact_attributes(
file_data,
header,
offset_size,
length_size,
&mut compact,
&mut Vec::new(),
&mut |_| Ok(()),
)?;
if let Some(a) = compact.into_iter().find(|a| a.name == name) {
return Ok(Some(a));
}
// Record: heap ID + message flags(1) + creation order(4) + hash(4); the
// hash is the last field.
let hash = jenkins_lookup3(name.as_bytes());
let hash_at = usize::from(btree_hdr.record_size) - 4;
let records = find_btree_v2_records(file_data, &btree_hdr, offset_size, &mut |r| match r
.get(hash_at..hash_at + 4)
{
Some(h) => u32::from_le_bytes([h[0], h[1], h[2], h[3]]).cmp(&hash),
None => core::cmp::Ordering::Less,
})?;
let id_len = usize::from(fh.heap_id_length);
for record in &records {
let Some(id_bytes) = record.data.get(..id_len) else {
continue;
};
let attr = fh
.read_managed_object(file_data, id_bytes, offset_size)
.and_then(|d| AttributeMessage::parse_in_file(&d, file_data, offset_size, length_size));
// One that cannot be read is left out, as from a listing.
if let Ok(attr) = attr
&& attr.name == name
{
return Ok(Some(attr));
}
}
Ok(None)
}
/// The attributes stored in the object header itself (compact storage), and
/// each one's creation order into `orders`.
fn extract_compact_attributes(
file_data: &[u8],
header: &ObjectHeader,
offset_size: u8,
length_size: u8,
attrs: &mut Vec<AttributeMessage>,
orders: &mut Vec<u32>,
on_error: &mut dyn FnMut(FormatError) -> Result<(), FormatError>,
) -> Result<(), FormatError> {
for msg in &header.messages {
if msg.msg_type == MessageType::Attribute {
let attr = if shared_message::is_shared(msg.flags) {
@@ -489,34 +630,7 @@ fn extract_attributes_with(
}
}
}
// Check for dense attributes via AttributeInfo message
let attr_info = find_attribute_info(header, offset_size)?;
if let Some(info) = &attr_info
&& let Some(fh_addr) = info.fractal_heap_address
{
extract_dense_attributes(
file_data,
info,
fh_addr,
offset_size,
length_size,
&mut attrs,
&mut orders,
on_error,
)?;
}
// An object that tracks attribute creation order lists its attributes
// in that order (h5py's `track_order=True`), as libhdf5 does; otherwise
// they come in storage order.
if attr_info.is_some_and(|i| i.max_creation_index.is_some()) {
let mut paired: Vec<(u32, AttributeMessage)> = orders.into_iter().zip(attrs).collect();
paired.sort_by_key(|(o, _)| *o);
attrs = paired.into_iter().map(|(_, a)| a).collect();
}
Ok(attrs)
Ok(())
}
/// Find and parse the Attribute Info message from an object header.
@@ -547,7 +661,7 @@ fn extract_dense_attributes(
on_error: &mut dyn FnMut(FormatError) -> Result<(), FormatError>,
) -> Result<(), FormatError> {
// Parse fractal heap
let fh = FractalHeapHeader::parse(file_data, fh_addr as usize, offset_size, length_size)?;
let fh = FractalHeapHeader::parse(file_data, to_usize(fh_addr)?, offset_size, length_size)?;
// Parse B-tree v2 for name index (type 8)
let btree_addr = attr_info
@@ -556,7 +670,8 @@ fn extract_dense_attributes(
expected: 1,
available: 0,
})?;
let btree_hdr = BTreeV2Header::parse(file_data, btree_addr as usize, offset_size, length_size)?;
let btree_hdr =
BTreeV2Header::parse(file_data, to_usize(btree_addr)?, offset_size, length_size)?;
let records = collect_btree_v2_records(file_data, &btree_hdr, offset_size, length_size)?;
for record in &records {
+179 -37
View File
@@ -2,10 +2,12 @@
#[cfg(not(feature = "std"))]
use alloc::vec::Vec;
use core::cmp::Ordering;
#[cfg(feature = "checksum")]
use byteorder::{ByteOrder, LittleEndian};
use crate::addr::to_usize;
use crate::error::FormatError;
/// Parsed B-tree v2 header (signature "BTHD").
@@ -216,7 +218,7 @@ pub fn collect_btree_v2_records(
// Root is a leaf
parse_leaf_records(
file_data,
header.root_node_address as usize,
to_usize(header.root_node_address)?,
header.num_records_in_root,
header.record_size,
)
@@ -225,7 +227,7 @@ pub fn collect_btree_v2_records(
let mut records = Vec::new();
collect_internal_records(
file_data,
header.root_node_address as usize,
to_usize(header.root_node_address)?,
header.num_records_in_root,
header.depth,
header.record_size,
@@ -289,9 +291,10 @@ fn parse_leaf_records(
Ok(records)
}
/// Recursively collect records from an internal node.
#[allow(clippy::too_many_arguments, clippy::only_used_in_recursion)]
fn collect_internal_records(
/// An internal node's layout: where its records start, and its children as
/// `(address, record count)`.
#[allow(clippy::too_many_arguments)]
fn read_internal_node(
file_data: &[u8],
offset: usize,
num_records: u16,
@@ -299,11 +302,8 @@ fn collect_internal_records(
record_size: u16,
node_size: u32,
offset_size: u8,
length_size: u8,
max_leaf_nrec: u64,
budget: &mut usize,
out: &mut Vec<BTreeV2Record>,
) -> Result<(), FormatError> {
) -> Result<(usize, Vec<(u64, u16)>), FormatError> {
// signature(4) + version(1) + type(1) = 6
ensure_len(file_data, offset, 6)?;
if &file_data[offset..offset + 4] != b"BTIN" {
@@ -314,7 +314,7 @@ fn collect_internal_records(
let rs = record_size as usize;
let mut pos = offset + 6;
// Read all records first
// Records first
let records_total = nr.checked_mul(rs).ok_or(FormatError::UnexpectedEof {
expected: usize::MAX,
available: file_data.len(),
@@ -346,7 +346,6 @@ fn collect_internal_records(
let child_ptr_size = offset_size as usize + nrec_width + total_nrec_width;
ensure_len(file_data, pos, num_children * child_ptr_size)?;
// Read child pointers
let mut children = Vec::with_capacity(num_children);
for _ in 0..num_children {
let addr = read_offset(file_data, pos, offset_size)?;
@@ -356,6 +355,61 @@ fn collect_internal_records(
pos += total_nrec_width; // skip total records in subtree
children.push((addr, child_nrec));
}
Ok((records_start, children))
}
/// Record `i` of an internal node whose records start at `records_start`.
fn internal_record(
file_data: &[u8],
records_start: usize,
i: usize,
rs: usize,
) -> Result<&[u8], FormatError> {
let overflow = || FormatError::UnexpectedEof {
expected: usize::MAX,
available: file_data.len(),
};
let rec_start = i
.checked_mul(rs)
.and_then(|o| records_start.checked_add(o))
.ok_or_else(overflow)?;
let rec_end = rec_start.checked_add(rs).ok_or_else(overflow)?;
file_data
.get(rec_start..rec_end)
.ok_or(FormatError::UnexpectedEof {
expected: rec_end,
available: file_data.len(),
})
}
/// Recursively collect records from an internal node.
#[allow(clippy::too_many_arguments, clippy::only_used_in_recursion)]
fn collect_internal_records(
file_data: &[u8],
offset: usize,
num_records: u16,
depth: u16,
record_size: u16,
node_size: u32,
offset_size: u8,
length_size: u8,
max_leaf_nrec: u64,
budget: &mut usize,
out: &mut Vec<BTreeV2Record>,
) -> Result<(), FormatError> {
let nr = num_records as usize;
let rs = record_size as usize;
let (records_start, children) = read_internal_node(
file_data,
offset,
num_records,
depth,
record_size,
node_size,
offset_size,
max_leaf_nrec,
)?;
let child_depth = depth - 1;
// Interleave: child[0], record[0], child[1], record[1], ..., child[nr]
// We collect child[0] records, then record[0], then child[1], etc.
@@ -364,12 +418,12 @@ fn collect_internal_records(
// Before parsing, so a refused tree is not also a large allocation.
spend(budget, usize::from(child_nrec))?;
let leaf_recs =
parse_leaf_records(file_data, child_addr as usize, child_nrec, record_size)?;
parse_leaf_records(file_data, to_usize(child_addr)?, child_nrec, record_size)?;
out.extend(leaf_recs);
} else {
collect_internal_records(
file_data,
child_addr as usize,
to_usize(child_addr)?,
child_nrec,
child_depth,
record_size,
@@ -384,32 +438,10 @@ fn collect_internal_records(
// Add record[i] (except after the last child)
if i < nr {
let rec_offset = i.checked_mul(rs).ok_or(FormatError::UnexpectedEof {
expected: usize::MAX,
available: file_data.len(),
})?;
let rec_start =
records_start
.checked_add(rec_offset)
.ok_or(FormatError::UnexpectedEof {
expected: usize::MAX,
available: file_data.len(),
})?;
let rec_end = rec_start
.checked_add(rs)
.ok_or(FormatError::UnexpectedEof {
expected: usize::MAX,
available: file_data.len(),
})?;
if rec_end > file_data.len() {
return Err(FormatError::UnexpectedEof {
expected: rec_end,
available: file_data.len(),
});
}
let data = internal_record(file_data, records_start, i, rs)?;
spend(budget, 1)?;
out.push(BTreeV2Record {
data: file_data[rec_start..rec_end].to_vec(),
data: data.to_vec(),
});
}
}
@@ -417,6 +449,116 @@ fn collect_internal_records(
Ok(())
}
/// The records of a B-tree v2 that fall in one key range, found by
/// descending the tree instead of reading all of it.
///
/// `cmp` places a record relative to the range: `Less` if the record sorts
/// before it, `Greater` if after, `Equal` if the record is in it. The tree
/// must be ordered consistently with `cmp`, as libhdf5 orders it (a link or
/// attribute name index by name hash, so all records with one hash form a
/// range whatever order their names are in). Only the nodes whose key
/// interval overlaps the range are read: O(depth) nodes plus those holding
/// the matches. Matches come in tree order.
pub fn find_btree_v2_records(
file_data: &[u8],
header: &BTreeV2Header,
offset_size: u8,
cmp: &mut dyn FnMut(&[u8]) -> Ordering,
) -> Result<Vec<BTreeV2Record>, FormatError> {
if header.total_records == 0 || header.num_records_in_root == 0 {
return Ok(Vec::new());
}
if header.depth > MAX_DEPTH {
return Err(FormatError::NestingDepthExceeded);
}
// As in `collect_btree_v2_records`: a valid tree cannot hold more
// records than the file has room for, however its children are shared.
let mut budget = file_data.len() / usize::from(header.record_size.max(1));
let max_leaf_nrec = max_records_leaf(header.node_size, header.record_size);
let mut out = Vec::new();
find_in_node(
file_data,
header,
to_usize(header.root_node_address)?,
header.num_records_in_root,
header.depth,
offset_size,
max_leaf_nrec,
cmp,
&mut budget,
&mut out,
)?;
Ok(out)
}
#[allow(clippy::too_many_arguments)]
fn find_in_node(
file_data: &[u8],
header: &BTreeV2Header,
offset: usize,
num_records: u16,
depth: u16,
offset_size: u8,
max_leaf_nrec: u64,
cmp: &mut dyn FnMut(&[u8]) -> Ordering,
budget: &mut usize,
out: &mut Vec<BTreeV2Record>,
) -> Result<(), FormatError> {
spend(budget, usize::from(num_records))?;
if depth == 0 {
let records = parse_leaf_records(file_data, offset, num_records, header.record_size)?;
out.extend(
records
.into_iter()
.filter(|r| cmp(&r.data) == Ordering::Equal),
);
return Ok(());
}
let rs = usize::from(header.record_size);
let (records_start, children) = read_internal_node(
file_data,
offset,
num_records,
depth,
header.record_size,
header.node_size,
offset_size,
max_leaf_nrec,
)?;
let nr = usize::from(num_records);
let mut order = Vec::with_capacity(nr);
for i in 0..nr {
order.push(cmp(internal_record(file_data, records_start, i, rs)?));
}
// Child `i` holds the keys between record `i - 1` and record `i`: it can
// hold a match unless the record before it is already past the range or
// the record after it is still before it.
for (i, &(child_addr, child_nrec)) in children.iter().enumerate() {
let after_left = i == 0 || order[i - 1] != Ordering::Greater;
let before_right = i == nr || order[i] != Ordering::Less;
if after_left && before_right {
find_in_node(
file_data,
header,
to_usize(child_addr)?,
child_nrec,
depth - 1,
offset_size,
max_leaf_nrec,
cmp,
budget,
out,
)?;
}
if i < nr && order[i] == Ordering::Equal {
out.push(BTreeV2Record {
data: internal_record(file_data, records_start, i, rs)?.to_vec(),
});
}
}
Ok(())
}
/// Most records a subtree whose root is at `depth` can hold (libhdf5's
/// `cum_max_nrec`). See [`node_info`].
fn cum_max_records(
@@ -385,6 +385,59 @@ mod tests {
assert!(nodes > 0);
}
/// Descending to a key range finds exactly the records a full read
/// holds in it — runs of equal keys that straddle node boundaries
/// included — at every depth, and nothing for keys not in the tree.
#[test]
fn a_key_range_search_matches_a_full_scan() {
use crate::btree_v2::find_btree_v2_records;
use core::cmp::Ordering;
let rs = 11usize;
// Keys 0, 0, 0, 2, 2, 2, 4, ...: runs of three, odd keys missing.
for n in [1usize, 45, 46, 1150, 30_000] {
let mut recs = Vec::with_capacity(n * rs);
for i in 0..n {
let mut r = vec![0u8; rs];
r[..8].copy_from_slice(&((i / 3 * 2) as u64).to_be_bytes());
r[8..].copy_from_slice(&[(i % 3) as u8, 0, 0]);
recs.extend_from_slice(&r);
}
let base = 4096u64;
let tree = build_btree_v2(params(512, 11), &recs, base, 8, 8).unwrap();
let mut file = vec![0u8; base as usize];
file.extend_from_slice(&tree);
let hdr = BTreeV2Header::parse(&file, base as usize, 8, 8).unwrap();
let all = collect_btree_v2_records(&file, &hdr, 8, 8).unwrap();
let key = |r: &[u8]| u64::from_be_bytes(r[..8].try_into().unwrap());
let last = key(&all[n - 1].data);
let probes = (0..=last + 1).step_by(if n > 1000 { 37 } else { 1 });
for k in probes.chain([last, last + 1, u64::MAX]) {
let found =
find_btree_v2_records(&file, &hdr, 8, &mut |r: &[u8]| key(r).cmp(&k)).unwrap();
let want: Vec<&[u8]> = all
.iter()
.map(|r| r.data.as_slice())
.filter(|r| key(r) == k)
.collect();
let got: Vec<&[u8]> = found.iter().map(|r| r.data.as_slice()).collect();
assert_eq!(got, want, "n {n} key {k}");
assert_eq!(
got.len(),
if k % 2 == 0 && k <= last {
want.len()
} else {
0
}
);
}
// Every record, or none, when the whole tree is in or out of range.
let every = find_btree_v2_records(&file, &hdr, 8, &mut |_| Ordering::Equal).unwrap();
assert_eq!(every.len(), n);
let none = find_btree_v2_records(&file, &hdr, 8, &mut |_| Ordering::Less).unwrap();
assert!(none.is_empty());
}
}
#[test]
fn a_node_too_small_or_too_big_is_an_error() {
assert!(build_btree_v2(params(16, 11), &records(1, 11), 0, 8, 8).is_err());
+20 -14
View File
@@ -6,7 +6,8 @@ use alloc::{format, vec::Vec};
#[cfg(feature = "checksum")]
use byteorder::{ByteOrder, LittleEndian};
use crate::btree_v2::{BTreeV2Header, collect_btree_v2_records};
use crate::addr::to_usize;
use crate::btree_v2::{BTreeV2Header, find_btree_v2_records};
use crate::error::FormatError;
use crate::filter_pipeline::FilterPipeline;
@@ -354,6 +355,7 @@ impl FractalHeapHeader {
id_bytes: &[u8],
offset_size: u8,
) -> Result<Vec<u8>, FormatError> {
crate::lookup_stats::heap_object_read();
let Some(&first) = id_bytes.first() else {
return Err(FormatError::UnexpectedEof {
expected: 1,
@@ -448,7 +450,7 @@ impl FractalHeapHeader {
}
let hdr = BTreeV2Header::parse(
file_data,
self.huge_btree_address as usize,
to_usize(self.huge_btree_address)?,
self.offset_size,
self.length_size,
)?;
@@ -463,8 +465,12 @@ impl FractalHeapHeader {
if hdr.tree_type != expected_type || usize::from(hdr.record_size) < rec_len {
return Err(heap_error("unexpected huge-object B-tree record type"));
}
let records =
collect_btree_v2_records(file_data, &hdr, self.offset_size, self.length_size)?;
// Records are ordered by ID (the last field): descend to the ones
// equal to `key` instead of reading the whole index.
let id_at = rec_len - ls;
let records = find_btree_v2_records(file_data, &hdr, self.offset_size, &mut |r| {
le_uint(&r[id_at..id_at + ls]).cmp(&key)
})?;
for rec in &records {
let d = &rec.data;
if d.len() < rec_len {
@@ -533,24 +539,24 @@ impl FractalHeapHeader {
self.read_from_direct_block(
file_data,
DirectBlock {
addr: self.root_block_address as usize,
addr: to_usize(self.root_block_address)?,
size: self.starting_block_size,
heap_offset: 0,
filtered_size: self.root_direct_block_filtered_size,
filter_mask: self.root_direct_block_filter_mask,
},
heap_offset,
obj_len as usize,
to_usize(obj_len)?,
)
} else {
// Root is an indirect block — limit recursion to 64 levels
self.read_from_indirect_block(
file_data,
self.root_block_address as usize,
to_usize(self.root_block_address)?,
self.current_rows_in_root_indirect_block,
0, // block offset
heap_offset,
obj_len as usize,
to_usize(obj_len)?,
offset_size,
64, // max recursion depth
)
@@ -572,11 +578,11 @@ impl FractalHeapHeader {
) -> Result<Vec<u8>, FormatError> {
if target_offset < block.heap_offset {
return Err(FormatError::UnexpectedEof {
expected: block.heap_offset as usize,
available: target_offset as usize,
expected: to_usize(block.heap_offset)?,
available: to_usize(target_offset)?,
});
}
let local_offset = (target_offset - block.heap_offset) as usize;
let local_offset = to_usize(target_offset - block.heap_offset)?;
if let Some(pipeline) = &self.filter_pipeline {
let stored_len = usize::try_from(block.filtered_size)
.map_err(|_| heap_error("direct block size"))?;
@@ -673,7 +679,7 @@ impl FractalHeapHeader {
return self.read_from_direct_block(
file_data,
DirectBlock {
addr: child_addr as usize,
addr: to_usize(child_addr)?,
size: block_size,
heap_offset: current_heap_offset,
filtered_size,
@@ -705,7 +711,7 @@ impl FractalHeapHeader {
{
return self.read_from_indirect_block(
file_data,
child_addr as usize,
to_usize(child_addr)?,
child_nrows,
current_heap_offset,
target_offset,
@@ -719,7 +725,7 @@ impl FractalHeapHeader {
}
Err(FormatError::UnexpectedEof {
expected: target_offset as usize + length,
expected: to_usize(target_offset)?.saturating_add(length),
available: file_data.len(),
})
}
+185 -32
View File
@@ -6,7 +6,9 @@
#[cfg(not(feature = "std"))]
use alloc::{string::String, vec::Vec};
use crate::btree_v2::{BTreeV2Header, collect_btree_v2_records};
use crate::addr::to_usize;
use crate::btree_v2::{BTreeV2Header, collect_btree_v2_records, find_btree_v2_records};
use crate::checksum::jenkins_lookup3;
use crate::error::FormatError;
use crate::fractal_heap::FractalHeapHeader;
use crate::group_v1::{self, GroupEntry};
@@ -93,13 +95,14 @@ fn for_each_dense_link(
mut visit: impl FnMut(LinkMessage),
) -> Result<(), FormatError> {
// Parse fractal heap
let fh = FractalHeapHeader::parse(file_data, fh_addr as usize, offset_size, length_size)?;
let fh = FractalHeapHeader::parse(file_data, to_usize(fh_addr)?, offset_size, length_size)?;
// Parse B-tree v2 for name index
let btree_addr = link_info
.btree_name_index_address
.ok_or_else(|| FormatError::PathNotFound(String::from("no B-tree v2 name index")))?;
let btree_hdr = BTreeV2Header::parse(file_data, btree_addr as usize, offset_size, length_size)?;
let btree_hdr =
BTreeV2Header::parse(file_data, to_usize(btree_addr)?, offset_size, length_size)?;
let records = collect_btree_v2_records(file_data, &btree_hdr, offset_size, length_size)?;
for record in &records {
@@ -181,10 +184,55 @@ fn find_symbolic_link(
if !is_v2_group(object_header) {
return Ok(None);
}
let is_symbolic = |t: &LinkTarget| !matches!(t, LinkTarget::Hard { .. });
// As when all links were scanned: the last symbolic link of that name.
Ok(
links_named(file_data, object_header, name, offset_size, length_size)?
.into_iter()
.rev()
.map(|link| link.link_target)
.find(|t| !matches!(t, LinkTarget::Hard { .. })),
)
}
/// B-tree v2 record type of a dense group's link name index.
const LINK_NAME_INDEX: u8 = 5;
/// The links called `name` in a v2 group (a valid group has at most one).
///
/// In dense storage the link name index (a v2 B-tree of lookup3 name
/// hashes, record type 5) is descended to the records with the name's hash,
/// and only their links are read from the heap — O(log n) instead of every
/// link. libhdf5 orders records with equal hashes by name; all of them are
/// read and compared here, so that order does not matter. An index of
/// another type is scanned in full.
fn links_named(
file_data: &[u8],
object_header: &ObjectHeader,
name: &str,
offset_size: u8,
length_size: u8,
) -> Result<Vec<LinkMessage>, FormatError> {
let mut found = Vec::new();
let link_info = find_link_info(object_header, offset_size)?;
let mut found = None;
if let Some(fh_addr) = link_info.fractal_heap_address {
let Some(fh_addr) = link_info.fractal_heap_address else {
for msg in &object_header.messages {
if msg.msg_type == MessageType::Link
&& let Some(link) = parse_link(&msg.data, offset_size)?
&& link.name == name
{
found.push(link);
}
}
return Ok(found);
};
let fh = FractalHeapHeader::parse(file_data, to_usize(fh_addr)?, offset_size, length_size)?;
let btree_addr = link_info
.btree_name_index_address
.ok_or_else(|| FormatError::PathNotFound(String::from("no B-tree v2 name index")))?;
let btree_hdr =
BTreeV2Header::parse(file_data, to_usize(btree_addr)?, offset_size, length_size)?;
if btree_hdr.tree_type != LINK_NAME_INDEX {
for_each_dense_link(
file_data,
&link_info,
@@ -192,26 +240,134 @@ fn find_symbolic_link(
offset_size,
length_size,
|link| {
if link.name == name && is_symbolic(&link.link_target) {
found = Some(link.link_target);
if link.name == name {
found.push(link);
}
},
)?;
} else {
for msg in &object_header.messages {
if msg.msg_type == MessageType::Link {
let Some(link) = parse_link(&msg.data, offset_size)? else {
continue;
};
if link.name == name && is_symbolic(&link.link_target) {
found = Some(link.link_target);
}
}
return Ok(found);
}
// Record: hash(4) + heap ID.
let hash = jenkins_lookup3(name.as_bytes());
let records = find_btree_v2_records(file_data, &btree_hdr, offset_size, &mut |r| {
match r.get(..4) {
Some(h) => u32::from_le_bytes([h[0], h[1], h[2], h[3]]).cmp(&hash),
// Too short to hold a hash (a corrupt record size): never a match.
None => core::cmp::Ordering::Less,
}
})?;
let id_len = usize::from(fh.heap_id_length);
for record in &records {
let Some(id_bytes) = record.data.get(4..4 + id_len) else {
continue;
};
let link_data = fh.read_managed_object(file_data, id_bytes, offset_size)?;
if let Some(link) = parse_link(&link_data, offset_size)?
&& link.name == name
{
found.push(link);
}
}
Ok(found)
}
/// The link [`resolve_path_any`] follows for one path component `name` of
/// the group with header `object_header`: a hard link (as `Hard`), else a
/// soft or external link of that name, else `None`. Fails with
/// `PathNotFound` if the object is not a group.
fn lookup_link(
file_data: &[u8],
object_header: &ObjectHeader,
name: &str,
offset_size: u8,
length_size: u8,
) -> Result<Option<LinkTarget>, FormatError> {
if is_v1_group(object_header) {
let entries = resolve_group_entries(file_data, object_header, offset_size, length_size)?;
if let Some(e) = entries
.iter()
.find(|e| e.name == name && e.object_header_address != u64::MAX)
{
return Ok(Some(LinkTarget::Hard {
object_header_address: e.object_header_address,
}));
}
return find_symbolic_link(file_data, object_header, name, offset_size, length_size);
}
if !is_v2_group(object_header) {
return Err(FormatError::PathNotFound(String::from(
"object header is not a group",
)));
}
let links = links_named(file_data, object_header, name, offset_size, length_size)?;
if let Some(addr) = links.iter().find_map(|l| match l.link_target {
LinkTarget::Hard {
object_header_address,
} if object_header_address != u64::MAX => Some(object_header_address),
_ => None,
}) {
return Ok(Some(LinkTarget::Hard {
object_header_address: addr,
}));
}
Ok(links
.into_iter()
.rev()
.map(|link| link.link_target)
.find(|t| !matches!(t, LinkTarget::Hard { .. })))
}
/// The object header address of the child called `name` of the group at
/// `group_address`: the address [`resolve_group_children`] lists under that
/// name, or `PathNotFound` if it lists none.
///
/// A dense group's child is found through its link name index (see
/// [`links_named`]) and only the named link is read and, if it is a soft
/// link, followed — not every link in the group. A v1 group is listed.
pub fn resolve_child(
file_data: &[u8],
superblock: &Superblock,
group_address: u64,
name: &str,
) -> Result<u64, FormatError> {
let os = superblock.offset_size;
let ls = superblock.length_size;
let not_found = || FormatError::PathNotFound(String::from(name));
let header = ObjectHeader::parse(file_data, to_usize(group_address)?, os, ls)?;
if !is_v2_group(&header) || is_v1_group(&header) {
return resolve_group_children(file_data, superblock, group_address)?
.into_iter()
.find(|e| e.name == name)
.map(|e| e.object_header_address)
.ok_or_else(not_found);
}
let links = links_named(file_data, &header, name, os, ls)?;
// The listing puts hard links before resolved soft links.
if let Some(addr) = links.iter().find_map(|l| match l.link_target {
LinkTarget::Hard {
object_header_address,
} => Some(object_header_address),
_ => None,
}) {
return Ok(addr);
}
for link in links {
if let LinkTarget::Soft { target_path } = link.link_target {
return match resolve_path_from(file_data, superblock, group_address, &target_path) {
// Left out of the listing: dangling, cyclic, or in another file.
Err(
FormatError::PathNotFound(_)
| FormatError::NestingDepthExceeded
| FormatError::ExternalLinkUnsupported { .. },
) => Err(not_found()),
other => other,
};
}
}
Err(not_found())
}
/// Find and parse the Link Info message from an object header.
fn find_link_info(
object_header: &ObjectHeader,
@@ -298,7 +454,7 @@ pub fn resolve_group_children(
) -> Result<Vec<GroupEntry>, FormatError> {
let os = superblock.offset_size;
let ls = superblock.length_size;
let header = ObjectHeader::parse(file_data, group_address as usize, os, ls)?;
let header = ObjectHeader::parse(file_data, to_usize(group_address)?, os, ls)?;
let mut entries = Vec::new();
let mut soft = Vec::new();
@@ -383,24 +539,21 @@ fn resolve_path_following_links(
let ls = superblock.length_size;
let mut current_addr = start;
let mut current_header = ObjectHeader::parse(file_data, start as usize, os, ls)?;
let mut current_header = ObjectHeader::parse(file_data, to_usize(start)?, os, ls)?;
for (i, component) in components.iter().enumerate() {
let entries = resolve_group_entries(file_data, &current_header, os, ls)?;
let found = entries
.iter()
.find(|e| e.name == *component && e.object_header_address != u64::MAX);
match found {
Some(entry) => {
match lookup_link(file_data, &current_header, component, os, ls)? {
Some(LinkTarget::Hard {
object_header_address,
}) => {
if i == components.len() - 1 {
return Ok(entry.object_header_address);
return Ok(object_header_address);
}
current_addr = entry.object_header_address;
current_header = ObjectHeader::parse(file_data, current_addr as usize, os, ls)?;
current_addr = object_header_address;
current_header = ObjectHeader::parse(file_data, to_usize(current_addr)?, os, ls)?;
}
None => {
return match find_symbolic_link(file_data, &current_header, component, os, ls)? {
found => {
return match found {
Some(LinkTarget::Soft { target_path }) => {
if depth >= MAX_SOFT_LINK_DEPTH {
return Err(FormatError::NestingDepthExceeded);
+1
View File
@@ -108,6 +108,7 @@ pub mod lane_partition;
pub mod link_info;
pub mod link_message;
pub mod local_heap;
pub mod lookup_stats;
pub mod message_type;
pub mod metadata_cache;
pub mod metadata_index;
@@ -0,0 +1,31 @@
//! Work counters for tests of lookup cost (feature `lookup-stats`).
//!
//! Counts fractal-heap objects read — each is one link or attribute message
//! decoded out of a dense group or dense attribute storage — so a test can
//! check that finding one name reads a handful of them, not the whole group.
//! Per thread, so tests running in parallel do not see each other's reads.
//! Without the feature the counting compiles to nothing.
#[cfg(feature = "lookup-stats")]
std::thread_local! {
static HEAP_OBJECTS: core::cell::Cell<u64> = const { core::cell::Cell::new(0) };
}
/// Record one heap object read.
#[inline(always)]
pub(crate) fn heap_object_read() {
#[cfg(feature = "lookup-stats")]
HEAP_OBJECTS.with(|c| c.set(c.get() + 1));
}
/// Heap objects read on this thread since the last [`reset`].
#[cfg(feature = "lookup-stats")]
pub fn heap_objects_read() -> u64 {
HEAP_OBJECTS.with(core::cell::Cell::get)
}
/// Zero this thread's counters.
#[cfg(feature = "lookup-stats")]
pub fn reset() {
HEAP_OBJECTS.with(|c| c.set(0));
}
+2 -1
View File
@@ -19,7 +19,8 @@ rayon = { version = "1", optional = true }
tempfile = { workspace = true }
criterion = { workspace = true }
clawhdf5-io = { path = "../clawhdf5-io", version = "2.7.0", features = ["mmap"] }
clawhdf5-format = { path = "../clawhdf5-format", version = "2.7.0", features = ["parallel", "fast-checksum"] }
clawhdf5-format = { path = "../clawhdf5-format", version = "2.7.0", features = ["parallel", "fast-checksum", "lookup-stats"] }
serde_json = "1"
clawhdf5-filters = { path = "../clawhdf5-filters", version = "2.7.0" }
[[bench]]
+44 -13
View File
@@ -28,7 +28,7 @@ use clawhdf5_format::superblock::Superblock;
use clawhdf5_io::HDF5Read;
use crate::error::Error;
use crate::types::{AttrValue, DType, classify_datatype, read_attrs};
use crate::types::{AttrValue, DType, classify_datatype, read_attr, read_attrs};
/// A lazy HDF5 file handle that parses metadata on demand.
///
@@ -304,12 +304,7 @@ impl<'f, R: HDF5Read> LazyGroup<'f, R> {
/// Get a dataset within this group by name.
pub fn dataset(&self, name: &str) -> Result<LazyDataset<'f, R>, Error> {
let entries = self.children()?;
let entry = entries
.iter()
.find(|e| e.name == name)
.ok_or_else(|| Error::Format(FormatError::PathNotFound(name.to_string())))?;
let hdr = self.file.get_or_parse_header(entry.object_header_address)?;
let hdr = self.file.get_or_parse_header(self.child_address(name)?)?;
if !has_message(&hdr, MessageType::DataLayout) {
return Err(Error::NotADataset(name.to_string()));
}
@@ -322,17 +317,38 @@ impl<'f, R: HDF5Read> LazyGroup<'f, R> {
/// Get a subgroup within this group by name.
pub fn group(&self, name: &str) -> Result<LazyGroup<'f, R>, Error> {
let entries = self.children()?;
let entry = entries
.iter()
.find(|e| e.name == name)
.ok_or_else(|| Error::Format(FormatError::PathNotFound(name.to_string())))?;
Ok(LazyGroup {
file: self.file,
address: entry.object_header_address,
address: self.child_address(name)?,
})
}
/// The attribute called `name`, or `None` if it has none by that name
/// (or it cannot be read) — the value [`attrs`](Self::attrs) has under
/// that name, found without reading the other attributes when they are
/// stored densely.
pub fn attr(&self, name: &str) -> Result<Option<AttrValue>, Error> {
let hdr = self.file.get_or_parse_header(self.address)?;
let data = self.file.hdf5_bytes();
read_attr(
data,
&hdr,
name,
self.file.offset_size(),
self.file.length_size(),
)
}
/// The object header address of the child called `name`: the entry of
/// the group's listing with that name, looked up through the group's
/// name index rather than by listing the group (see
/// [`group_v2::resolve_child`]).
fn child_address(&self, name: &str) -> Result<u64, Error> {
let data = self.file.hdf5_bytes();
group_v2::resolve_child(data, &self.file.superblock, self.address, name)
.map_err(Error::Format)
}
/// This group's links that can be opened: hard links, and soft links
/// resolved to their targets (see
/// [`group_v2::resolve_group_children`]); dangling, external and
@@ -555,6 +571,21 @@ impl<'f, R: HDF5Read> LazyDataset<'f, R> {
)
}
/// The attribute called `name`, or `None` if it has none by that name
/// (or it cannot be read) — the value [`attrs`](Self::attrs) has under
/// that name, found without reading the other attributes when they are
/// stored densely.
pub fn attr(&self, name: &str) -> Result<Option<AttrValue>, Error> {
let data = self.file.hdf5_bytes();
read_attr(
data,
&self.header,
name,
self.file.offset_size(),
self.file.length_size(),
)
}
/// A header message's payload, resolved through the shared-message
/// indirection when needed (e.g. a committed datatype). See
/// [`clawhdf5_format::shared_message::message_data`].
+44 -13
View File
@@ -23,7 +23,7 @@ use clawhdf5_format::superblock::Superblock;
use clawhdf5_io::MmapReader;
use crate::error::Error;
use crate::types::{AttrValue, DType, classify_datatype, read_attrs};
use crate::types::{AttrValue, DType, classify_datatype, read_attr, read_attrs};
/// An HDF5 file opened via memory mapping.
///
@@ -242,12 +242,7 @@ impl<'f> MmapGroup<'f> {
/// Get a dataset within this group by name.
pub fn dataset(&self, name: &str) -> Result<MmapDataset<'f>, Error> {
let entries = self.children()?;
let entry = entries
.iter()
.find(|e| e.name == name)
.ok_or_else(|| Error::Format(FormatError::PathNotFound(name.to_string())))?;
let hdr = self.file.parse_header(entry.object_header_address)?;
let hdr = self.file.parse_header(self.child_address(name)?)?;
if !has_message(&hdr, MessageType::DataLayout) {
return Err(Error::NotADataset(name.to_string()));
}
@@ -260,17 +255,38 @@ impl<'f> MmapGroup<'f> {
/// Get a subgroup within this group by name.
pub fn group(&self, name: &str) -> Result<MmapGroup<'f>, Error> {
let entries = self.children()?;
let entry = entries
.iter()
.find(|e| e.name == name)
.ok_or_else(|| Error::Format(FormatError::PathNotFound(name.to_string())))?;
Ok(MmapGroup {
file: self.file,
address: entry.object_header_address,
address: self.child_address(name)?,
})
}
/// The attribute called `name`, or `None` if it has none by that name
/// (or it cannot be read) — the value [`attrs`](Self::attrs) has under
/// that name, found without reading the other attributes when they are
/// stored densely.
pub fn attr(&self, name: &str) -> Result<Option<AttrValue>, Error> {
let hdr = self.file.parse_header(self.address)?;
let data = self.file.hdf5_bytes();
read_attr(
data,
&hdr,
name,
self.file.offset_size(),
self.file.length_size(),
)
}
/// The object header address of the child called `name`: the entry of
/// the group's listing with that name, looked up through the group's
/// name index rather than by listing the group (see
/// [`group_v2::resolve_child`]).
fn child_address(&self, name: &str) -> Result<u64, Error> {
let data = self.file.meta()?;
group_v2::resolve_child(data, &self.file.superblock, self.address, name)
.map_err(Error::Format)
}
/// This group's links that can be opened: hard links, and soft links
/// resolved to their targets (see
/// [`group_v2::resolve_group_children`]); dangling, external and
@@ -506,6 +522,21 @@ impl<'f> MmapDataset<'f> {
)
}
/// The attribute called `name`, or `None` if it has none by that name
/// (or it cannot be read) — the value [`attrs`](Self::attrs) has under
/// that name, found without reading the other attributes when they are
/// stored densely.
pub fn attr(&self, name: &str) -> Result<Option<AttrValue>, Error> {
let data = self.file.hdf5_bytes();
read_attr(
data,
&self.header,
name,
self.file.offset_size(),
self.file.length_size(),
)
}
/// A header message's payload, resolved through the shared-message
/// indirection when needed (e.g. a committed datatype). See
/// [`clawhdf5_format::shared_message::message_data`].
+72 -16
View File
@@ -23,7 +23,7 @@ use clawhdf5_format::superblock::Superblock;
use crate::cache_image::{self, ImageView};
use crate::error::Error;
use crate::types::{AttrValue, DType, classify_datatype, read_attrs};
use crate::types::{AttrValue, DType, classify_datatype, read_attr, read_attrs};
// ---------------------------------------------------------------------------
// FileData — internal storage for either owned bytes or an mmap
@@ -230,9 +230,10 @@ impl File {
/// A `Dataset` handle for the object header at `address` (an address
/// from a group listing, or one kept from an earlier lookup), without
/// resolving a path. Resolving a path walks every group on it, which in
/// a large group costs a scan of its links; keep the address instead to
/// open the same dataset repeatedly.
/// resolving a path. Resolving a path looks each component up in its
/// group (through the name index of a dense group; a v1 group's entries
/// are scanned); keep the address instead to open the same dataset
/// repeatedly.
pub fn dataset_at(&self, address: u64) -> Result<Dataset<'_>, Error> {
let hdr = self.parse_header(address)?;
if !has_message(&hdr, MessageType::DataLayout) {
@@ -245,6 +246,17 @@ impl File {
.check_open()
}
/// A `Group` handle for the object header at `address` (from
/// [`Group::entries`], or kept from an earlier lookup), without
/// resolving a path. Like [`group`](Self::group), the object is not
/// checked to be a group; a non-group has no children.
pub fn group_at(&self, address: u64) -> Group<'_> {
Group {
file: self,
address,
}
}
/// Resolve a path and return a `Group` handle.
///
/// The path uses `/` separators (e.g., `"sensors"`).
@@ -483,12 +495,7 @@ impl<'f> Group<'f> {
/// Get a dataset within this group by name.
pub fn dataset(&self, name: &str) -> Result<Dataset<'f>, Error> {
let entries = self.children()?;
let entry = entries
.iter()
.find(|e| e.name == name)
.ok_or_else(|| Error::Format(FormatError::PathNotFound(name.to_string())))?;
let hdr = self.file.parse_header(entry.object_header_address)?;
let hdr = self.file.parse_header(self.child_address(name)?)?;
if !has_message(&hdr, MessageType::DataLayout) {
return Err(Error::NotADataset(name.to_string()));
}
@@ -501,17 +508,51 @@ impl<'f> Group<'f> {
/// Get a subgroup within this group by name.
pub fn group(&self, name: &str) -> Result<Group<'f>, Error> {
let entries = self.children()?;
let entry = entries
.iter()
.find(|e| e.name == name)
.ok_or_else(|| Error::Format(FormatError::PathNotFound(name.to_string())))?;
Ok(Group {
file: self.file,
address: entry.object_header_address,
address: self.child_address(name)?,
})
}
/// The attribute called `name`, or `None` if it has none by that name
/// (or it cannot be read) — the value [`attrs`](Self::attrs) has under
/// that name, found without reading the other attributes when they are
/// stored densely.
pub fn attr(&self, name: &str) -> Result<Option<AttrValue>, Error> {
let hdr = self.file.parse_header(self.address)?;
let data = self.file.data.as_bytes();
read_attr(
data,
&hdr,
name,
self.file.offset_size(),
self.file.length_size(),
)
}
/// The object header address of the child called `name`: the entry of
/// the group's listing with that name, looked up through the group's
/// name index rather than by listing the group (see
/// [`group_v2::resolve_child`]).
fn child_address(&self, name: &str) -> Result<u64, Error> {
let data = self.file.data.meta()?;
group_v2::resolve_child(data, &self.file.superblock, self.address, name)
.map_err(Error::Format)
}
/// This group's children that can be opened, as `(name, object header
/// address)` in listing order — the entries [`datasets`](Self::datasets)
/// and [`groups`](Self::groups) are drawn from. Open one with
/// [`File::dataset_at`] or [`File::group_at`] to skip looking its name
/// up again, or keep the addresses to revisit the objects.
pub fn entries(&self) -> Result<Vec<(String, u64)>, Error> {
Ok(self
.children()?
.into_iter()
.map(|e| (e.name, e.object_header_address))
.collect())
}
/// This group's links that can be opened: hard links, and soft links
/// resolved to their targets (see
/// [`group_v2::resolve_group_children`]); dangling, external and
@@ -1051,6 +1092,21 @@ impl<'f> Dataset<'f> {
)
}
/// The attribute called `name`, or `None` if it has none by that name
/// (or it cannot be read) — the value [`attrs`](Self::attrs) has under
/// that name, found without reading the other attributes when they are
/// stored densely.
pub fn attr(&self, name: &str) -> Result<Option<AttrValue>, Error> {
let data = self.file.data.as_bytes();
read_attr(
data,
&self.header,
name,
self.file.offset_size(),
self.file.length_size(),
)
}
/// Verify this dataset's content against its stored provenance hash
/// (`_provenance_sha256`, written automatically on save when a
/// [`Provenance`](clawhdf5_format::provenance::Provenance) is set — see
+29
View File
@@ -182,6 +182,35 @@ pub(crate) fn read_attrs(
))
}
/// The attribute called `name` on the object with header `header`, decoded
/// as [`read_attrs`] decodes it, or `None` (see
/// [`find_attribute_in_file`](clawhdf5_format::attribute::find_attribute_in_file)).
pub(crate) fn read_attr(
file_data: &[u8],
header: &clawhdf5_format::object_header::ObjectHeader,
name: &str,
offset_size: u8,
length_size: u8,
) -> Result<Option<AttrValue>, crate::Error> {
let Some(msg) = clawhdf5_format::attribute::find_attribute_in_file(
file_data,
header,
name,
offset_size,
length_size,
)?
else {
return Ok(None);
};
Ok(attrs_to_map(
std::slice::from_ref(&msg),
file_data,
offset_size,
length_size,
)
.remove(name))
}
pub(crate) fn attrs_to_map(
attrs: &[clawhdf5_format::attribute::AttributeMessage],
file_data: &[u8],
@@ -211,6 +211,30 @@ fn dense_attribute_stored_as_a_huge_heap_object() {
assert!(matches!(&attrs["bigger"], AttrValue::I64Array(v) if *v == bigger));
}
/// Enough huge attributes that the huge-object B-tree has internal nodes:
/// each one is found by descending it by heap ID (libhdf5 orders the
/// records of indirectly addressed huge objects by ID), and every value
/// matches what was written.
#[test]
fn many_huge_attributes_are_found_through_their_index() {
skip_if_no_python!();
let (_dir, path) = h5py_file(
"d = f.create_dataset('d', data=[1.0])\n\
for i in range(300):\n\
\x20 d.attrs['h%03d' % i] = np.arange(600, dtype='i8') + i\n",
);
let f = File::open(&path).unwrap();
let d = f.dataset("d").unwrap();
let attrs = d.attrs().unwrap();
assert_eq!(attrs.len(), 300);
for i in 0..300i64 {
let name = format!("h{i:03}");
let want: Vec<i64> = (0..600).map(|v| v + i).collect();
assert!(matches!(&attrs[&name], AttrValue::I64Array(v) if *v == want), "{name}");
assert!(matches!(d.attr(&name).unwrap(), Some(AttrValue::I64Array(v)) if v == want), "{name}");
}
}
/// A group whose link heap has a deflate I/O filter (set on the group
/// creation property list), with 3 000 links and one link whose message is
/// larger than the heap's managed-object limit, so it is a huge object.
@@ -0,0 +1,410 @@
//! Looking one name up in a dense group (links in a fractal heap, indexed by
//! a v2 B-tree of name hashes) or in dense attribute storage reads the name
//! index, not every link: O(log n) index nodes and only the links whose
//! lookup3 hash equals the name's. Before, every lookup decoded all n links,
//! so opening each child of a 35 001-link group by name decoded ~1.2e9.
//!
//! The file is written by h5py (libhdf5 orders the index), with names whose
//! hashes collide, and every result is compared with what h5py reads.
//!
//! Skipped when python3 with h5py is unavailable, unless
//! `CLAWHDF5_REQUIRE_INTEROP=1`.
use std::collections::{BTreeMap, HashMap};
use std::process::Command;
use std::sync::OnceLock;
use std::time::{Duration, Instant};
use clawhdf5::{AttrValue, File, LazyFile, MmapFile};
use clawhdf5_format::checksum::jenkins_lookup3;
use clawhdf5_format::error::FormatError;
use clawhdf5_format::lookup_stats;
fn python() -> String {
std::env::var("CLAWHDF5_PYTHON").unwrap_or_else(|_| "python3".to_string())
}
fn interop_required() -> bool {
std::env::var("CLAWHDF5_REQUIRE_INTEROP").is_ok_and(|v| v == "1")
}
fn python_available() -> bool {
Command::new(python())
.args(["-c", "import h5py"])
.output()
.map(|o| o.status.success())
.unwrap_or(false)
}
macro_rules! skip_if_no_python {
() => {
if !python_available() {
assert!(
!interop_required(),
"CLAWHDF5_REQUIRE_INTEROP=1 but python3 with h5py is not available"
);
eprintln!("SKIP: python3 with h5py not available");
return;
}
};
}
fn run_python(script: &str) -> String {
let output = Command::new(python())
.args(["-c", script])
.output()
.expect("failed to run python");
assert!(
output.status.success(),
"Python script failed:\nSTDOUT: {}\nSTDERR: {}",
String::from_utf8_lossy(&output.stdout),
String::from_utf8_lossy(&output.stderr)
);
String::from_utf8_lossy(&output.stdout).trim().to_string()
}
/// Links in the big group, as libhdf5's `h5stat_newgrat.h5` has.
const LINKS: usize = 35_001;
/// Attributes on the dense-attribute dataset.
const ATTRS: usize = 3_000;
/// Pairs of distinct names with equal lookup3 hashes, found by search (the
/// hash is fixed, so the pairs are too).
fn colliding_pairs(count: usize) -> Vec<(String, String)> {
let mut seen: HashMap<u32, String> = HashMap::new();
let mut pairs = Vec::new();
for i in 0.. {
let name = format!("c{i}");
let h = jenkins_lookup3(name.as_bytes());
if let Some(first) = seen.insert(h, name.clone()) {
pairs.push((first, name));
if pairs.len() == count {
break;
}
}
}
pairs
}
/// What h5py reads: link values, attribute values, and which of the
/// missing names it finds as links and as attributes (none).
type H5pyView = (
BTreeMap<String, i64>,
BTreeMap<String, i64>,
Vec<String>,
Vec<String>,
);
struct Fixture {
_dir: tempfile::TempDir,
path: String,
/// Names in the big group, with the value of the scalar dataset each
/// links to, as h5py reads them.
links: BTreeMap<String, i64>,
/// Names that are not links but hash like one that is.
missing_links: Vec<String>,
/// Attributes of `/x`, as h5py reads them.
attrs: BTreeMap<String, i64>,
missing_attrs: Vec<String>,
}
fn fixture() -> &'static Fixture {
static FIXTURE: OnceLock<Fixture> = OnceLock::new();
FIXTURE.get_or_init(|| {
let pairs = colliding_pairs(6);
for (a, b) in &pairs {
assert_ne!(a, b);
assert_eq!(jenkins_lookup3(a.as_bytes()), jenkins_lookup3(b.as_bytes()));
}
// Pairs 0-2 both present (either can be the one libhdf5 orders
// first), pairs 3-5 only the first: its partner must not be found.
// "k69209"/"k155448" is the pair the writer once misordered.
let mut present: Vec<String> = vec!["k69209".into(), "k155448".into()];
let mut missing: Vec<String> = Vec::new();
for (i, (a, b)) in pairs.into_iter().enumerate() {
present.push(a);
if i < 3 {
present.push(b);
} else {
missing.push(b);
}
}
missing.extend(["", "nope", "n35001x", "N1"].map(String::from));
let mut links = present.clone();
let mut i = 0;
while links.len() < LINKS {
links.push(format!("n{i}"));
i += 1;
}
let mut attrs = present.clone();
attrs.extend((0..ATTRS - present.len()).map(|i| format!("a{i}")));
let dir = tempfile::tempdir().unwrap();
let path = dir.path().join("big.h5").display().to_string();
// The names go through a file: 35 001 of them overflow an argument.
let names = dir.path().join("names.json");
std::fs::write(
&names,
serde_json::to_string(&(&links, &attrs, &missing)).unwrap(),
)
.unwrap();
let names = names.display();
let out = run_python(&format!(
"import h5py, json, numpy as np\n\
links, attrs, missing = json.load(open(r'{names}'))\n\
with h5py.File(r'{path}', 'w', libver='latest') as f:\n\
\x20 g = f.create_group('g')\n\
\x20 for i, n in enumerate(links):\n\
\x20 g.create_dataset(n, data=np.int64(i))\n\
\x20 x = f.create_dataset('x', data=np.int64(0))\n\
\x20 for i, n in enumerate(attrs):\n\
\x20 x.attrs[n] = np.int64(1000 + i)\n\
with h5py.File(r'{path}', 'r') as f:\n\
\x20 g, a = f['g'], f['x'].attrs\n\
\x20 print(json.dumps([{{n: int(g[n][()]) for n in g}}, {{n: int(a[n]) for n in a}},\n\
\x20 [n for n in missing if n and n in g], [n for n in missing if n and n in a]]))",
));
let (links, attrs, found_links, found_attrs): H5pyView =
serde_json::from_str(&out).unwrap();
assert_eq!(links.len(), LINKS);
assert_eq!(attrs.len(), ATTRS);
assert!(found_links.is_empty() && found_attrs.is_empty());
Fixture {
_dir: dir,
path,
links,
missing_links: missing.clone(),
attrs,
missing_attrs: missing,
}
})
}
fn is_not_found(e: &clawhdf5::Error) -> bool {
matches!(e, clawhdf5::Error::Format(FormatError::PathNotFound(_)))
}
#[test]
fn one_link_lookup_reads_the_index_not_every_link() {
skip_if_no_python!();
let fx = fixture();
let f = File::open(&fx.path).unwrap();
let g = f.group("g").unwrap();
for (name, value) in &fx.links {
lookup_stats::reset();
let ds = g.dataset(name).unwrap();
// One link decoded per lookup, two where hashes collide — not 35 001.
let read = lookup_stats::heap_objects_read();
assert!(read <= 2, "looking up {name} read {read} heap objects");
assert_eq!(ds.read_i64().unwrap(), vec![*value], "{name}");
}
for name in &fx.missing_links {
lookup_stats::reset();
let err = g.dataset(name).unwrap_err();
assert!(is_not_found(&err), "{name:?}: {err:?}");
assert!(lookup_stats::heap_objects_read() <= 2, "{name:?}");
}
// A path resolves each component the same way.
for name in ["k155448", "n0", "n34000"] {
lookup_stats::reset();
let ds = f.dataset(&format!("/g/{name}")).unwrap();
assert!(lookup_stats::heap_objects_read() <= 2);
assert_eq!(ds.read_i64().unwrap(), vec![fx.links[name]]);
}
}
#[test]
fn one_attribute_lookup_reads_the_index_not_every_attribute() {
skip_if_no_python!();
let fx = fixture();
let f = File::open(&fx.path).unwrap();
let x = f.dataset("x").unwrap();
let all = x.attrs().unwrap();
assert_eq!(all.len(), ATTRS);
for (name, value) in &fx.attrs {
lookup_stats::reset();
let got = x.attr(name).unwrap();
assert!(lookup_stats::heap_objects_read() <= 2, "{name}");
assert!(
matches!(got, Some(AttrValue::I64(v)) if v == *value),
"{name}: {got:?}"
);
assert!(matches!(all.get(name), Some(AttrValue::I64(v)) if v == value));
}
for name in &fx.missing_attrs {
lookup_stats::reset();
assert!(x.attr(name).unwrap().is_none(), "{name:?}");
assert!(lookup_stats::heap_objects_read() <= 2, "{name:?}");
}
// Compact attributes (on the root group: none) and a group's attributes.
assert!(f.root().attr("k69209").unwrap().is_none());
}
/// Every child of the big group opened by name through each file type,
/// within `limit`: with a scan per lookup this is ~1.2e9 link decodes.
#[test]
fn opening_every_child_of_a_35001_link_group_by_name_is_quick() {
skip_if_no_python!();
let fx = fixture();
let limit = Duration::from_secs(120);
let started = Instant::now();
let check_time = |n: usize| {
assert!(
started.elapsed() < limit,
"{n} lookups took {:?}",
started.elapsed()
);
};
let f = File::open(&fx.path).unwrap();
let g = f.group("g").unwrap();
for (n, (name, value)) in fx.links.iter().enumerate() {
assert_eq!(g.dataset(name).unwrap().read_i64().unwrap(), vec![*value]);
check_time(n);
}
// The listing hands out entries: open each by address.
let entries = g.entries().unwrap();
assert_eq!(entries.len(), LINKS);
for (name, address) in &entries {
let ds = f.dataset_at(*address).unwrap();
assert_eq!(ds.read_i64().unwrap(), vec![fx.links[name]]);
}
assert!(f.group_at(g_address(&f)).dataset("n0").is_ok());
let m = MmapFile::open(&fx.path).unwrap();
let mg = m.group("g").unwrap();
for (n, (name, value)) in fx.links.iter().enumerate() {
assert_eq!(mg.dataset(name).unwrap().read_i64().unwrap(), vec![*value]);
check_time(n);
}
assert!(mg.group("nope").is_err_and(|e| is_not_found(&e)));
let l = LazyFile::open_mmap(&fx.path).unwrap();
let lg = l.group("g").unwrap();
for (n, (name, value)) in fx.links.iter().enumerate() {
assert_eq!(lg.dataset(name).unwrap().read_i64().unwrap(), vec![*value]);
check_time(n);
}
let lx = l.dataset("x").unwrap();
assert!(
matches!(lx.attr("k155448").unwrap(), Some(AttrValue::I64(v)) if v == fx.attrs["k155448"])
);
assert!(
lg.dataset(&fx.missing_links[0])
.is_err_and(|e| is_not_found(&e))
);
}
fn g_address(f: &File) -> u64 {
f.root()
.entries()
.unwrap()
.into_iter()
.find(|(n, _)| n == "g")
.unwrap()
.1
}
/// Every kind of link, looked up by name in a dense group (through the name
/// index) and in a compact one, opens what h5py opens and nothing it cannot:
/// hard links, soft links (absolute, relative, to a group), and not a
/// dangling soft link, an external link or a missing name.
#[test]
fn links_of_every_kind_resolve_by_name_as_in_h5py() {
skip_if_no_python!();
let dir = tempfile::tempdir().unwrap();
let path = dir.path().join("links.h5").display().to_string();
// For each group and name: "dataset <value>", "group", or "none" as
// h5py sees it.
let out = run_python(&format!(
"import h5py, json, numpy as np\n\
with h5py.File(r'{path}', 'w', libver='latest') as f:\n\
\x20 for gname, n in (('dense', 20), ('compact', 2)):\n\
\x20 g = f.create_group(gname)\n\
\x20 for i in range(n):\n\
\x20 g.create_dataset(f'd{{i}}', data=np.int64(100 + i))\n\
\x20 s = g.create_group('sub')\n\
\x20 s.create_dataset('x', data=np.int64(7))\n\
\x20 g['abs'] = h5py.SoftLink(f'/{{gname}}/d1')\n\
\x20 g['rel'] = h5py.SoftLink('sub/x')\n\
\x20 g['tosub'] = h5py.SoftLink('sub')\n\
\x20 g['dangling'] = h5py.SoftLink('/nowhere')\n\
\x20 g['ext'] = h5py.ExternalLink('other.h5', '/y')\n\
names = ['d0', 'd1', 'sub', 'abs', 'rel', 'tosub', 'dangling', 'ext', 'nope', '']\n\
seen = {{}}\n\
with h5py.File(r'{path}', 'r') as f:\n\
\x20 for gname in ('dense', 'compact'):\n\
\x20 g = f[gname]\n\
\x20 for n in names:\n\
\x20 try:\n\
\x20 o = g[n] if n else None\n\
\x20 except (KeyError, OSError):\n\
\x20 o = None\n\
\x20 if isinstance(o, h5py.Dataset):\n\
\x20 seen[f'{{gname}}/{{n}}'] = f'dataset {{int(o[()])}}'\n\
\x20 elif isinstance(o, h5py.Group):\n\
\x20 seen[f'{{gname}}/{{n}}'] = 'group'\n\
\x20 else:\n\
\x20 seen[f'{{gname}}/{{n}}'] = 'none'\n\
print(json.dumps(seen))",
));
let seen: BTreeMap<String, String> = serde_json::from_str(&out).unwrap();
assert_eq!(seen.len(), 20);
let f = File::open(&path).unwrap();
// The dense group's links are in a heap, the compact group's in its
// header.
for (gname, dense) in [("dense", true), ("compact", false)] {
let g = f.group(gname).unwrap();
lookup_stats::reset();
g.dataset("d0").unwrap();
assert_eq!(lookup_stats::heap_objects_read() > 0, dense, "{gname}");
}
let m = MmapFile::open(&path).unwrap();
let l = LazyFile::open_mmap(&path).unwrap();
for (key, want) in &seen {
let (gname, name) = key.split_once('/').unwrap();
let got = {
let g = f.group(gname).unwrap();
match (g.dataset(name), g.group(name)) {
(Ok(ds), _) => format!("dataset {}", ds.read_i64().unwrap()[0]),
(Err(clawhdf5::Error::NotADataset(_)), Ok(sub)) => {
// A group: it has the child `x` (checks the address).
assert!(sub.dataset("x").is_ok() || name == "sub" || name == "tosub");
"group".to_string()
}
(Err(e), Err(e2)) => {
assert!(is_not_found(&e) && is_not_found(&e2), "{key}: {e:?} / {e2:?}");
"none".to_string()
}
(Err(e), Ok(_)) => panic!("{key}: dataset {e:?} but group ok"),
}
};
assert_eq!(&got, want, "{key}");
// The other readers agree, and a path through the group resolves the
// same way.
let mg = m.group(gname).unwrap();
let lg = l.group(gname).unwrap();
match want.strip_prefix("dataset ") {
Some(v) => {
let v: i64 = v.parse().unwrap();
assert_eq!(mg.dataset(name).unwrap().read_i64().unwrap(), vec![v]);
assert_eq!(lg.dataset(name).unwrap().read_i64().unwrap(), vec![v]);
let ds = f.dataset(&format!("/{gname}/{name}")).unwrap();
assert_eq!(ds.read_i64().unwrap(), vec![v], "{key}");
}
None if want == "group" => {
assert!(mg.group(name).unwrap().dataset("x").is_ok(), "{key}");
assert!(lg.group(name).unwrap().dataset("x").is_ok(), "{key}");
let ds = f.dataset(&format!("/{gname}/{name}/x")).unwrap();
assert_eq!(ds.read_i64().unwrap(), vec![7]);
}
None => {
assert!(mg.dataset(name).is_err_and(|e| is_not_found(&e)), "{key}");
assert!(lg.group(name).is_err_and(|e| is_not_found(&e)), "{key}");
}
}
}
}