fix(format): read huge, tiny and filtered fractal heap objects
A heap ID's type is in bits 4-5 of its first byte (H5HF_ID_TYPE_MASK 0x30); bits 6-7 are the ID version. The reader took the type from bits 6-7, so every huge object ID (0x10) was decoded as a managed one and failed — and since dense attributes are read all at once, one attribute over the heap's 4 KiB managed limit made every attribute on its object unreadable (netcdf4-python's issue671.nc / issue672.nc). - Huge objects (type 1): located directly from the ID when address and length fit in it, otherwise through the huge-object v2 B-tree (record types 1 and 2); filtered huge objects are decoded with the heap's pipeline and their filter mask. - Tiny objects (type 2): read from the ID itself. - Filtered heaps: the header's pipeline is parsed (it was skipped short, so the header checksum was read from the wrong place), indirect-block entries for direct blocks carry their filtered size and mask, and direct blocks are decoded before objects are read from them. - An unknown ID version is an error. FractalHeapHeader gains huge_btree_address, filter_pipeline, root_direct_block_filtered_size, root_direct_block_filter_mask, offset_size and length_size; read_managed_object now accepts any ID type. Regression tests (h5py-written, compared with h5py): dense_attribute_stored_as_a_huge_heap_object, dense_group_with_a_huge_link, dense_group_with_a_filtered_link_heap; unit tests tiny_object_is_read_from_the_id, huge_object_with_a_direct_id, unknown_heap_id_version_is_refused. Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
This commit is contained in:
osobh
@@ -1947,6 +1947,12 @@ mod tests {
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root_block_address: 0,
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current_rows_in_root_indirect_block: 0,
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managed_objects_count: 0,
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huge_btree_address: u64::MAX,
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filter_pipeline: None,
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root_direct_block_filtered_size: 0,
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root_direct_block_filter_mask: 0,
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offset_size: 8,
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length_size: 8,
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};
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let (off, len) = fh.decode_managed_id(&id).unwrap();
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assert_eq!(off, 100);
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@@ -1,12 +1,14 @@
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//! HDF5 Fractal Heap parsing for v2 group link storage.
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#[cfg(not(feature = "std"))]
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use alloc::vec::Vec;
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use alloc::{format, vec::Vec};
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#[cfg(feature = "checksum")]
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use byteorder::{ByteOrder, LittleEndian};
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use crate::btree_v2::{BTreeV2Header, collect_btree_v2_records};
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use crate::error::FormatError;
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use crate::filter_pipeline::FilterPipeline;
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/// Parsed fractal heap header (signature "FRHP").
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#[derive(Debug, Clone)]
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@@ -33,6 +35,23 @@ pub struct FractalHeapHeader {
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pub current_rows_in_root_indirect_block: u16,
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/// Total number of managed objects.
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pub managed_objects_count: u64,
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/// Address of the v2 B-tree indexing "huge" objects (undefined address
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/// when the heap has none). Huge objects are those larger than
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/// `max_managed_object_size`; they live outside the heap's blocks.
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pub huge_btree_address: u64,
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/// The heap's I/O filter pipeline, if it has one. It applies to managed
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/// direct blocks and to huge objects.
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pub filter_pipeline: Option<FilterPipeline>,
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/// Stored (filtered) size of the root direct block; meaningful only when
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/// the heap is filtered and its root is a direct block.
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pub root_direct_block_filtered_size: u64,
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/// Filter mask of the root direct block (bit *i* set = filter *i*
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/// skipped); meaningful only when the heap is filtered.
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pub root_direct_block_filter_mask: u32,
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/// Size of addresses in the file ("Size of Offsets").
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pub offset_size: u8,
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/// Size of lengths in the file ("Size of Lengths").
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pub length_size: u8,
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}
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fn read_offset(data: &[u8], pos: usize, size: u8) -> Result<u64, FormatError> {
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@@ -79,6 +98,38 @@ fn is_undefined(val: u64, offset_size: u8) -> bool {
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}
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}
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/// Little-endian unsigned integer of up to 8 bytes.
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fn le_uint(bytes: &[u8]) -> u64 {
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bytes
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.iter()
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.take(8)
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.enumerate()
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.fold(0u64, |acc, (i, &b)| acc | (u64::from(b) << (i * 8)))
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}
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fn heap_error(msg: &str) -> FormatError {
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FormatError::ChunkedReadError(format!("fractal heap: {msg}"))
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}
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/// Heap ID type, from bits 4-5 of an ID's first byte (libhdf5's
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/// `H5HF_ID_TYPE_MASK`, 0x30); bits 6-7 are the ID version, which must be 0.
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const HEAP_ID_MANAGED: u8 = 0;
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const HEAP_ID_HUGE: u8 = 1;
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const HEAP_ID_TINY: u8 = 2;
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/// The type (0 managed, 1 huge, 2 tiny) of a heap ID from its first byte,
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/// refusing an ID version other than 0.
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fn heap_id_type(first: u8) -> Result<u8, FormatError> {
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if first >> 6 != 0 {
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return Err(heap_error("unsupported heap ID version"));
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}
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Ok((first >> 4) & 0x03)
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}
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/// v2 B-tree record types indexing a heap's huge objects.
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const BTREE_HUGE_INDIRECT: u8 = 1;
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const BTREE_HUGE_INDIRECT_FILTERED: u8 = 2;
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impl FractalHeapHeader {
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/// Parse a fractal heap header at the given offset.
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pub fn parse(
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@@ -122,11 +173,17 @@ impl FractalHeapHeader {
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]);
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pos += 4;
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// Skip several fixed fields: next_huge_object_id(ls), btree_huge_objects_address(os),
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// free_space_managed_blocks(ls), managed_block_free_space_manager_address(os),
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// next_huge_object_id (length_size)
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ensure_len(file_data, pos, ls)?;
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pos += ls;
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// btree_huge_objects_address (offset_size)
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let huge_btree_address = read_offset(file_data, pos, offset_size)?;
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pos += os;
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// Skip: free_space_managed_blocks(ls), managed_block_free_space_manager_address(os),
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// managed_space_in_heap(ls), allocated_managed_space_in_heap(ls),
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// direct_block_allocation_iterator_offset(ls)
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let skip_size = 5 * ls + 2 * os;
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let skip_size = 4 * ls + os;
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ensure_len(file_data, pos, skip_size)?;
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pos += skip_size;
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@@ -134,14 +191,9 @@ impl FractalHeapHeader {
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let managed_objects_count = read_offset(file_data, pos, length_size)?;
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pos += ls;
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// huge_objects_size (length_size)
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pos += ls;
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// huge_objects_count (length_size)
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pos += ls;
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// tiny_objects_size (length_size)
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pos += ls;
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// tiny_objects_count (length_size)
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pos += ls;
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// huge_objects_size, huge_objects_count, tiny_objects_size,
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// tiny_objects_count (length_size each)
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pos += 4 * ls;
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// table_width (2)
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ensure_len(file_data, pos, 2)?;
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@@ -175,16 +227,28 @@ impl FractalHeapHeader {
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ensure_len(file_data, pos, 2)?;
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let current_rows_in_root_indirect_block =
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u16::from_le_bytes([file_data[pos], file_data[pos + 1]]);
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#[allow(unused_variables, unused_mut, unused_assignments)]
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let mut pos = pos + 2;
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pos += 2;
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// Skip IO filter encoded info if present
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// With I/O filters: root direct block's filtered size (length_size),
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// its filter mask (4), then the encoded filter pipeline message.
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let mut filter_pipeline = None;
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let mut root_direct_block_filtered_size = 0;
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let mut root_direct_block_filter_mask = 0;
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if io_filter_encoded_length > 0 {
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// root_block_filter_info_size (length_size) + filter_mask (4)
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#[allow(unused_assignments)]
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{
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pos += ls + 4;
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}
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root_direct_block_filtered_size = read_offset(file_data, pos, length_size)?;
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pos += ls;
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ensure_len(file_data, pos, 4)?;
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root_direct_block_filter_mask = u32::from_le_bytes([
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file_data[pos],
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file_data[pos + 1],
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file_data[pos + 2],
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file_data[pos + 3],
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]);
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pos += 4;
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let n = io_filter_encoded_length as usize;
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ensure_len(file_data, pos, n)?;
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filter_pipeline = Some(FilterPipeline::parse(&file_data[pos..pos + n])?);
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pos += n;
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}
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// Validate header checksum
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@@ -200,6 +264,8 @@ impl FractalHeapHeader {
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});
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}
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}
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#[cfg(not(feature = "checksum"))]
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let _ = pos;
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Ok(FractalHeapHeader {
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heap_id_length,
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@@ -213,13 +279,19 @@ impl FractalHeapHeader {
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root_block_address,
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current_rows_in_root_indirect_block,
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managed_objects_count,
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huge_btree_address,
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filter_pipeline,
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root_direct_block_filtered_size,
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root_direct_block_filter_mask,
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offset_size,
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length_size,
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})
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}
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/// Decode a managed heap ID into (offset_in_heap, object_length).
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///
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/// The heap ID layout for managed objects (type 0):
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/// - Byte 0: bits 6-7 = type (0), bits 4-5 = version (0), bits 0-3 = reserved
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/// - Byte 0: bits 6-7 = version (0), bits 4-5 = type (0), bits 0-3 = reserved
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/// - Bytes 1+: offset (max_heap_size bits, LE) then length (remaining bits, LE)
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pub fn decode_managed_id(&self, id_bytes: &[u8]) -> Result<(u64, u64), FormatError> {
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if id_bytes.is_empty() {
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@@ -229,8 +301,8 @@ impl FractalHeapHeader {
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});
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}
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let id_type = (id_bytes[0] >> 6) & 0x03;
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if id_type != 0 {
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let id_type = heap_id_type(id_bytes[0])?;
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if id_type != HEAP_ID_MANAGED {
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return Err(FormatError::InvalidHeapIdType(id_type));
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}
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@@ -269,12 +341,183 @@ impl FractalHeapHeader {
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Ok((heap_offset, length_val))
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}
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/// Read a managed object from the heap given its raw heap ID bytes.
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/// Read any object from the heap given its raw heap ID bytes: managed
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/// (stored in the heap's blocks), huge (stored outside them, found
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/// directly from the ID or through the huge-object v2 B-tree, optionally
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/// filtered) or tiny (stored in the ID itself).
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///
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/// Despite its name this accepts every ID type; `offset_size` must match
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/// the one the header was parsed with.
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pub fn read_managed_object(
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&self,
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file_data: &[u8],
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id_bytes: &[u8],
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offset_size: u8,
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) -> Result<Vec<u8>, FormatError> {
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let Some(&first) = id_bytes.first() else {
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return Err(FormatError::UnexpectedEof {
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expected: 1,
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available: 0,
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});
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};
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match heap_id_type(first)? {
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HEAP_ID_MANAGED => self.read_heap_managed(file_data, id_bytes, offset_size),
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HEAP_ID_HUGE => self.read_huge_object(file_data, id_bytes),
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HEAP_ID_TINY => self.read_tiny_object(id_bytes),
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other => Err(FormatError::InvalidHeapIdType(other)),
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}
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}
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/// Whether a huge object's ID holds its address and length directly
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/// (libhdf5 does this when they fit in the ID), rather than a key into
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/// the huge-object B-tree.
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fn huge_ids_direct(&self) -> bool {
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let room = usize::from(self.heap_id_length).saturating_sub(1);
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let os = usize::from(self.offset_size);
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let ls = usize::from(self.length_size);
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if self.filter_pipeline.is_some() {
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room >= os + ls + 4 + ls
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} else {
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room >= os + ls
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}
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}
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/// Read a huge object (heap ID type 1).
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fn read_huge_object(&self, file_data: &[u8], id: &[u8]) -> Result<Vec<u8>, FormatError> {
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let os = usize::from(self.offset_size);
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let ls = usize::from(self.length_size);
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// (address, stored length, filter mask, decoded length); the last two
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// only matter for a filtered heap.
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let (addr, stored_len, mask, mem_len) = if self.huge_ids_direct() {
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let body = &id[1..];
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let need = if self.filter_pipeline.is_some() {
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os + ls + 4 + ls
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} else {
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os + ls
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};
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ensure_len(body, 0, need)?;
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let addr = le_uint(&body[..os]);
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let len = le_uint(&body[os..os + ls]);
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if self.filter_pipeline.is_some() {
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let mask = u32::from_le_bytes([
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body[os + ls],
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body[os + ls + 1],
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body[os + ls + 2],
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body[os + ls + 3],
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]);
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let mem = le_uint(&body[os + ls + 4..os + ls + 4 + ls]);
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(addr, len, mask, mem)
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} else {
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(addr, len, 0, len)
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}
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} else {
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let key_len = (usize::from(self.heap_id_length).saturating_sub(1)).min(8);
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ensure_len(id, 1, key_len)?;
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let key = le_uint(&id[1..1 + key_len]);
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self.find_huge_record(file_data, key)?
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};
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let start = usize::try_from(addr).map_err(|_| heap_error("huge object address"))?;
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let len = usize::try_from(stored_len).map_err(|_| heap_error("huge object length"))?;
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ensure_len(file_data, start, len)?;
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let stored = &file_data[start..start + len];
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match &self.filter_pipeline {
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None => Ok(stored.to_vec()),
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Some(pipeline) => {
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let mem = usize::try_from(mem_len).map_err(|_| heap_error("huge object size"))?;
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let out = crate::filters::decompress_chunk_masked(stored, pipeline, mem, 1, mask)?;
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if out.len() != mem {
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return Err(heap_error("filtered huge object decoded to the wrong size"));
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}
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Ok(out)
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}
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}
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}
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/// Look up huge object `key` in the huge-object v2 B-tree, returning
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/// (address, stored length, filter mask, decoded length).
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fn find_huge_record(
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&self,
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file_data: &[u8],
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key: u64,
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) -> Result<(u64, u64, u32, u64), FormatError> {
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if is_undefined(self.huge_btree_address, self.offset_size) {
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return Err(heap_error(
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"huge object ID but the heap has no huge-object index",
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));
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}
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let hdr = BTreeV2Header::parse(
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file_data,
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self.huge_btree_address as usize,
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self.offset_size,
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self.length_size,
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)?;
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let os = usize::from(self.offset_size);
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let ls = usize::from(self.length_size);
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let filtered = self.filter_pipeline.is_some();
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let (expected_type, rec_len) = if filtered {
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(BTREE_HUGE_INDIRECT_FILTERED, os + ls + 4 + ls + ls)
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} else {
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(BTREE_HUGE_INDIRECT, os + ls + ls)
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};
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if hdr.tree_type != expected_type || usize::from(hdr.record_size) < rec_len {
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return Err(heap_error("unexpected huge-object B-tree record type"));
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}
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let records =
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collect_btree_v2_records(file_data, &hdr, self.offset_size, self.length_size)?;
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for rec in &records {
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let d = &rec.data;
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if d.len() < rec_len {
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continue;
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}
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let addr = le_uint(&d[..os]);
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let len = le_uint(&d[os..os + ls]);
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if filtered {
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let mask = u32::from_le_bytes([
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d[os + ls],
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d[os + ls + 1],
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d[os + ls + 2],
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d[os + ls + 3],
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]);
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let mem = le_uint(&d[os + ls + 4..os + 2 * ls + 4]);
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let id = le_uint(&d[os + 2 * ls + 4..os + 3 * ls + 4]);
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if id == key {
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return Ok((addr, len, mask, mem));
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}
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} else {
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let id = le_uint(&d[os + ls..os + 2 * ls]);
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if id == key {
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return Ok((addr, len, 0, len));
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}
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}
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}
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Err(heap_error("huge object not found in its B-tree"))
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}
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/// Read a tiny object (heap ID type 2), stored in the ID itself.
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fn read_tiny_object(&self, id: &[u8]) -> Result<Vec<u8>, FormatError> {
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// libhdf5 uses a one-byte length (low 4 bits of byte 0) unless the ID
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// is long enough to need 12 bits, which then borrow byte 1.
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let extended = usize::from(self.heap_id_length).saturating_sub(1) > 17;
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let (len, start) = if extended {
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ensure_len(id, 0, 2)?;
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(
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((usize::from(id[0] & 0x0F)) << 8 | usize::from(id[1])) + 1,
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2,
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)
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} else {
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(usize::from(id[0] & 0x0F) + 1, 1)
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};
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ensure_len(id, start, len)?;
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Ok(id[start..start + len].to_vec())
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}
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/// Read a managed object (heap ID type 0).
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fn read_heap_managed(
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&self,
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file_data: &[u8],
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id_bytes: &[u8],
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offset_size: u8,
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) -> Result<Vec<u8>, FormatError> {
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let (heap_offset, obj_len) = self.decode_managed_id(id_bytes)?;
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@@ -289,12 +532,15 @@ impl FractalHeapHeader {
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// Root is a direct block
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self.read_from_direct_block(
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file_data,
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self.root_block_address as usize,
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self.starting_block_size,
|
||||
0, // block offset in heap = 0 for root
|
||||
DirectBlock {
|
||||
addr: self.root_block_address as usize,
|
||||
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,
|
||||
offset_size,
|
||||
)
|
||||
} else {
|
||||
// Root is an indirect block — limit recursion to 64 levels
|
||||
@@ -313,27 +559,41 @@ impl FractalHeapHeader {
|
||||
|
||||
/// Read an object from a direct block.
|
||||
///
|
||||
/// The heap offset is relative to the start of the block (including its header),
|
||||
/// so we just add it to the block address minus the block's heap offset.
|
||||
#[allow(clippy::too_many_arguments)]
|
||||
/// The heap offset is relative to the start of the block (including its
|
||||
/// header), so we just add it to the block address minus the block's heap
|
||||
/// offset. A filtered heap stores each direct block (header included)
|
||||
/// through its filter pipeline, so the block is decoded first.
|
||||
fn read_from_direct_block(
|
||||
&self,
|
||||
file_data: &[u8],
|
||||
block_addr: usize,
|
||||
_block_size: u64,
|
||||
block_heap_offset: u64,
|
||||
block: DirectBlock,
|
||||
target_offset: u64,
|
||||
length: usize,
|
||||
_offset_size: u8,
|
||||
) -> Result<Vec<u8>, FormatError> {
|
||||
if target_offset < block_heap_offset {
|
||||
if target_offset < block.heap_offset {
|
||||
return Err(FormatError::UnexpectedEof {
|
||||
expected: block_heap_offset as usize,
|
||||
expected: block.heap_offset as usize,
|
||||
available: target_offset as usize,
|
||||
});
|
||||
}
|
||||
let local_offset = (target_offset - block_heap_offset) as usize;
|
||||
let pos = block_addr
|
||||
let local_offset = (target_offset - block.heap_offset) as usize;
|
||||
if let Some(pipeline) = &self.filter_pipeline {
|
||||
let stored_len = usize::try_from(block.filtered_size)
|
||||
.map_err(|_| heap_error("direct block size"))?;
|
||||
let size = usize::try_from(block.size).map_err(|_| heap_error("direct block size"))?;
|
||||
ensure_len(file_data, block.addr, stored_len)?;
|
||||
let decoded = crate::filters::decompress_chunk_masked(
|
||||
&file_data[block.addr..block.addr + stored_len],
|
||||
pipeline,
|
||||
size,
|
||||
1,
|
||||
block.filter_mask,
|
||||
)?;
|
||||
ensure_len(&decoded, local_offset, length)?;
|
||||
return Ok(decoded[local_offset..local_offset + length].to_vec());
|
||||
}
|
||||
let pos = block
|
||||
.addr
|
||||
.checked_add(local_offset)
|
||||
.ok_or(FormatError::UnexpectedEof {
|
||||
expected: usize::MAX,
|
||||
@@ -371,19 +631,13 @@ impl FractalHeapHeader {
|
||||
let iblock_header = 5 + offset_size as usize + block_offset_bytes;
|
||||
let mut pos = iblock_addr + iblock_header;
|
||||
|
||||
// Compute block sizes for each row using the doubling table
|
||||
let tw = self.table_width as u64;
|
||||
|
||||
let nrows_usize = nrows as usize;
|
||||
|
||||
// Build table of (block_size, heap_offset) for each child entry
|
||||
let mut current_heap_offset = iblock_heap_offset;
|
||||
|
||||
// Rows below max_direct_rows hold direct blocks; rows at/above hold
|
||||
// child indirect blocks. (NOT the FRHP "starting rows" field.)
|
||||
let start_indirect = self.max_direct_rows();
|
||||
|
||||
// Read child addresses for direct block rows
|
||||
let max_direct_rows = nrows_usize.min(start_indirect);
|
||||
|
||||
for row in 0..max_direct_rows {
|
||||
@@ -393,35 +647,49 @@ impl FractalHeapHeader {
|
||||
let child_addr = read_offset(file_data, pos, offset_size)?;
|
||||
pos += offset_size as usize;
|
||||
|
||||
if self.io_filter_encoded_length > 0 {
|
||||
// filtered_size(length_size) + filter_mask(4)
|
||||
// Skip for now - we don't handle filtered direct blocks in fractal heaps
|
||||
pos += 4; // filter_mask - simplified
|
||||
}
|
||||
// A filtered heap stores each direct block's filtered size
|
||||
// (length_size) and filter mask (4) after its address.
|
||||
let (filtered_size, filter_mask) = if self.filter_pipeline.is_some() {
|
||||
let size = read_offset(file_data, pos, self.length_size)?;
|
||||
pos += usize::from(self.length_size);
|
||||
ensure_len(file_data, pos, 4)?;
|
||||
let mask = u32::from_le_bytes([
|
||||
file_data[pos],
|
||||
file_data[pos + 1],
|
||||
file_data[pos + 2],
|
||||
file_data[pos + 3],
|
||||
]);
|
||||
pos += 4;
|
||||
(size, mask)
|
||||
} else {
|
||||
(0, 0)
|
||||
};
|
||||
|
||||
if !is_undefined(child_addr, offset_size) {
|
||||
let block_end = current_heap_offset + block_size;
|
||||
if target_offset >= current_heap_offset && target_offset < block_end {
|
||||
return self.read_from_direct_block(
|
||||
file_data,
|
||||
child_addr as usize,
|
||||
block_size,
|
||||
current_heap_offset,
|
||||
target_offset,
|
||||
length,
|
||||
offset_size,
|
||||
);
|
||||
}
|
||||
let block_end = current_heap_offset.saturating_add(block_size);
|
||||
if !is_undefined(child_addr, offset_size)
|
||||
&& target_offset >= current_heap_offset
|
||||
&& target_offset < block_end
|
||||
{
|
||||
return self.read_from_direct_block(
|
||||
file_data,
|
||||
DirectBlock {
|
||||
addr: child_addr as usize,
|
||||
size: block_size,
|
||||
heap_offset: current_heap_offset,
|
||||
filtered_size,
|
||||
filter_mask,
|
||||
},
|
||||
target_offset,
|
||||
length,
|
||||
);
|
||||
}
|
||||
current_heap_offset += block_size;
|
||||
current_heap_offset = block_end;
|
||||
}
|
||||
}
|
||||
|
||||
// If we have indirect block rows
|
||||
// A child indirect block in row r spans exactly that row's block size
|
||||
// of heap space, so it has as many rows as a table of that total size
|
||||
// needs (not `row - start_indirect + 1`, which undercounts and makes
|
||||
// every object past the root's direct rows unreachable).
|
||||
// Rows at and above `start_indirect` hold child indirect blocks. A
|
||||
// child in row r spans exactly that row's block size of heap space,
|
||||
// so it has as many rows as a table of that total size needs.
|
||||
for row in start_indirect..nrows_usize {
|
||||
let child_space = self.block_size_for_row(row);
|
||||
let child_nrows = self.rows_for_size(child_space);
|
||||
@@ -495,6 +763,16 @@ impl FractalHeapHeader {
|
||||
}
|
||||
}
|
||||
|
||||
/// A managed direct block's location, extent and (for a filtered heap) its
|
||||
/// stored size and filter mask.
|
||||
struct DirectBlock {
|
||||
addr: usize,
|
||||
size: u64,
|
||||
heap_offset: u64,
|
||||
filtered_size: u64,
|
||||
filter_mask: u32,
|
||||
}
|
||||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
use super::*;
|
||||
@@ -640,7 +918,7 @@ mod tests {
|
||||
let hdr = FractalHeapHeader::parse(&file_data, 0, 8, 8).unwrap();
|
||||
|
||||
// Build a managed heap ID:
|
||||
// byte 0: type=0 (bits 6-7 = 00), version=0 (bits 4-5), reserved (bits 0-3)
|
||||
// byte 0: version=0 (bits 6-7), type=0 (bits 4-5), reserved (bits 0-3)
|
||||
// bytes 1-6: offset (max_heap_size=16 bits) then length (remaining bits)
|
||||
// For offset=0, length=13:
|
||||
// payload = offset | (length << 16) = 0 | (13 << 16) = 0x000D0000
|
||||
@@ -704,9 +982,46 @@ mod tests {
|
||||
fn invalid_heap_id_type() {
|
||||
let (file_data, _) = build_simple_heap(8, 8);
|
||||
let hdr = FractalHeapHeader::parse(&file_data, 0, 8, 8).unwrap();
|
||||
// Type = 1 (tiny) in bits 6-7
|
||||
let id = vec![0x40u8, 0, 0, 0, 0, 0, 0]; // bit 6 set = type 1
|
||||
// Type = 1 (huge) in bits 4-5 is not a managed ID
|
||||
let id = vec![0x10u8, 0, 0, 0, 0, 0, 0];
|
||||
let err = hdr.decode_managed_id(&id).unwrap_err();
|
||||
assert_eq!(err, FormatError::InvalidHeapIdType(1));
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn tiny_object_is_read_from_the_id() {
|
||||
let (file_data, _) = build_simple_heap(8, 8);
|
||||
let hdr = FractalHeapHeader::parse(&file_data, 0, 8, 8).unwrap();
|
||||
// Type 2 (0x20), length - 1 in the low 4 bits, data after.
|
||||
let id = [0x20 | 2, b'a', b'b', b'c', 0, 0, 0];
|
||||
assert_eq!(hdr.read_managed_object(&file_data, &id, 8).unwrap(), b"abc");
|
||||
// A length running past the ID is an error, not a short read.
|
||||
let id = [0x20 | 9, b'a', b'b', b'c', 0, 0, 0];
|
||||
assert!(hdr.read_managed_object(&file_data, &id, 8).is_err());
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn huge_object_with_a_direct_id() {
|
||||
// With IDs long enough for an address and a length, libhdf5 stores
|
||||
// huge objects' location in the ID instead of the huge-object B-tree.
|
||||
let (mut file_data, _) = build_simple_heap(8, 8);
|
||||
let mut hdr = FractalHeapHeader::parse(&file_data, 0, 8, 8).unwrap();
|
||||
hdr.heap_id_length = 17;
|
||||
file_data[900..905].copy_from_slice(b"huge!");
|
||||
let mut id = vec![0x10u8];
|
||||
id.extend_from_slice(&900u64.to_le_bytes());
|
||||
id.extend_from_slice(&5u64.to_le_bytes());
|
||||
assert_eq!(
|
||||
hdr.read_managed_object(&file_data, &id, 8).unwrap(),
|
||||
b"huge!"
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn unknown_heap_id_version_is_refused() {
|
||||
let (file_data, _) = build_simple_heap(8, 8);
|
||||
let hdr = FractalHeapHeader::parse(&file_data, 0, 8, 8).unwrap();
|
||||
let id = [0x40u8, 0, 0, 0, 0, 0, 0];
|
||||
assert!(hdr.read_managed_object(&file_data, &id, 8).is_err());
|
||||
}
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user