Module pack 

Pack files, indexes, and packfile I/O.

Structs

LocalPackInfo

Basic information about local packs.

PackData

Immutable bytes of a .pack, pack index, commit-graph, MIDX, or packed-refs file.

PackIndex

Parsed pack index with fanout-accelerated OID lookup and in-place table reads.

PackIndexEntry

Owned pack index row (collect from PackIndex::iter when needed).

PackIndexEntryRef

Borrowed view of one row in a pack index.

PackLookupOptions

Options controlling which local packs participate in a lookup pass.

ReuseWriteStats

Counters updated while streaming reused pack bytes.

SingleLocalPackReader

Sorted cat-file --batch reader for repos with exactly one local pack (hot-path benchmarks).

StreamingReuse

Active verbatim reuse context while streaming a pack body.

VerifyObjectRecord

A decoded object header record used by verify-pack.

Enums

PackedDeltaDependency

Dependency of a packed delta object at object_offset within pack_bytes.

PackedType

A pack object type as encoded in the packed stream header.

Constants

DEFAULT_PACK_DEPTH

Default in-pack delta chain depth when pack.depth is unset (matches Git).

Functions

apply_delta_depth_limit

Break only delta chains longer than max_depth edges in a target→base map.

clear_pack_cache

Drop pack/MIDX caches on every registered PackStore.

clear_pack_delta_base_cache

Drop only the process-wide delta-base LRU (indexes and pack bytes stay cached).

collect_local_pack_info

Collect aggregate local pack metrics.

collect_packed_delta_reuse_for_send

collect_packed_delta_reuse_for_send function.

compute_fanout_from_entries

Compute the 256-entry fanout from owned entries (legacy helper for tests).

compute_fanout_from_oid_slices

Compute fanout from a sorted OID list (used when writing v1 indexes in tests).

configure_delta_base_cache_from_config

Apply core.deltaBaseCacheLimit from repository config to the process-wide delta-base LRU.

hash_object_bytes

Hash canonical loose object bytes (kind SP size NUL data) with the repo hash width.

max_verify_pack_delta_depth

Longest delta-chain depth among verify-pack records (number of edges from base to tip).

oid_bytes_to_hex

oid_bytes_to_hex function.

pack_index_entry_matches_sha1_oid

True when entry stores a SHA-1 OID matching oid (SHA-256 pack entries are ignored).

pack_index_is_v1

Whether idx_path uses the legacy v1 pack-index format (no PACK signature).

packed_delta_base_oid

packed_delta_base_oid function.

packed_full_object_slice

When oid is stored as a full (non-delta) object in a local pack, return its verbatim packed bytes: the varint type+size header followed by the zlib stream.

packed_ref_delta_reuse_slice

If oid is stored as REF_DELTA or OFS_DELTA in a local pack and its base OID is in packed_set, return the base OID and the uncompressed delta payload (Git binary delta).

parse_pack_index_bytes

Parse pack index bytes (v1 or v2). When verify is true, check the trailing checksum.

read_alternates_recursive

Read alternates recursively, deduplicated in discovery order.

read_idx_object_ids

Read all object IDs from a .idx file.

read_local_pack_indexes

Read all valid .idx files in objects/pack.

read_local_pack_indexes_cached

Read all pack indexes under <objects_dir>/pack/ from the process-wide cache.

read_object_from_pack

Read an object from a pack file by its OID.

read_object_from_pack_at_offset

Read a packed object when the pack index entry is already known (batch cat-file workloads).

read_object_from_pack_bytes

Resolve an object from already-loaded pack bytes (used by verify-pack).

read_object_from_pack_into

Like read_object_from_pack, inflating into buf and reusing its capacity.

read_object_from_packs

Search all pack indexes in objects_dir for the given OID and read it.

read_object_from_packs_into

Like read_object_from_packs, inflating into buf and reusing its capacity.

read_object_info_from_pack

Read ObjectInfo for oid stored in idx’s pack without inflating the full object body.

read_object_info_from_pack_at_offset

Read ObjectInfo at a known pack offset (avoids a second index lookup in batch workloads).

read_object_info_from_packs

Search local packs for oid and return its kind and uncompressed size.

read_pack_bytes_cached

Read pack file bytes from the process-wide cache.

read_pack_index

Parse a pack index file (version 1 legacy or version 2), verifying the SHA-1 trailer checksum.

read_pack_index_cached

Read a single pack index from the process-wide cache (parses from disk on miss). Skips trailer verification.

read_pack_index_no_verify

Parse a pack index file without verifying the SHA-1 trailer checksum.

read_packed_delta_dependency

If the object at object_offset is a delta, return how it refers to its base.

refresh_pack_bytes_signature

Re-stamp the cached pack-bytes signature after deliberately touching pack_path’s mtime (object freshening). See the internal pack_cache::refresh_pack_signature helper.

reprepare_pack_directory_on_miss

Re-scan the pack directory when its mtime changed since the cached listing.

revalidate_stale_pack_bytes

Re-read pack_path when its on-disk signature differs from the cached entry.

skip_one_pack_object

skip_one_pack_object function.

slice_one_pack_object

Advance pos past one packed object (including zlib payload).

test_pack_cache_guard

Serializes tests that mutate the process-global pack cache (integration tests).

try_read_object_from_local_packs_cached

Resolve oid from local packs via the process-wide pack cache (cached .idx parses, cached pack bytes, fanout binary search, delta-base cache).

try_write_streaming_pack

Write a PACK stream to w using bitmap reachability and verbatim reuse when possible.

verify_pack_and_collect

Verify one pack/index pair and optionally return object records.

write_v2_pack_index

write_v2_pack_index function.

write_v2_pack_index_with_trailer

Write a version-2 .idx for entries describing objects in pack_path.