Module midx 

Multi-pack-index (MIDX) read and write.

Structs

MidxBtmpPackRange

One pack’s slice of the MIDX pseudo-bitmap namespace (BTMP chunk).

MidxObjectRef

A single MIDX-referenced object together with the pack it is attributed to.

MidxReuseTables

OID rows from the active multi-pack-index, plus reverse-index order for pack-reuse bitmap bits.

WriteMultiPackIndexOptions

Options for writing a multi-pack index (extension of the simple writer).

WriteMultiPackIndexResult

Result of write_multi_pack_index_with_options.

Enums

CompactError

Failure modes of compact_multi_pack_index, each mapping to one of git’s user-facing diagnostics in cmd_multi_pack_index_compact.

MidxBitmapWriteOutcome

Outcome of an optional MIDX reachability bitmap write.

Functions

cached_tip_midx_path

Whether a tip MIDX file exists under pack_dir (live filesystem probe).

clear_pack_midx_state

Build objects/pack/multi-pack-index for all pack indexes in pack_dir.

compact_multi_pack_index

git multi-pack-index compact <from> <to>: merge the inclusive chain range [from..to] (oldest→newest, matching git’s from=argv[0] / to=argv[1]) into a single new incremental layer, preserving pack order, and rewrite the chain as [layers before from] + [compacted layer] + [layers after to].

evict_midx_read_cache_for_pack_dir

Drop cached MIDX bytes and tip resolution after pack-directory changes.

format_midx_bitmapped_packs

Format test-tool read-midx --bitmap output for the active MIDX: per pack, a line with <pack>.pack, then bitmap_pos: and bitmap_nr:. Returns an error whose message is MIDX does not contain the BTMP chunk when the MIDX has no BTMP chunk (mirrors nth_bitmapped_pack in git/midx.c).

format_midx_dump

format_midx_dump function.

format_midx_dump_layer

Like format_midx_dump but reads a specific layer by checksum (chain layer or root MIDX). Used by test-tool read-midx <object-dir> <checksum>.

format_midx_show_objects

Human-readable dump of the MIDX (matches test-tool read-midx layout closely enough for grep-based tests). Emit one line per MIDX object: {oid} {offset}\t{pack-idx-name} (matches Git test-read-midx.c).

format_midx_show_objects_layer

Like format_midx_show_objects but reads a specific layer by checksum.

load_midx_reuse_tables

Load OID / object-offset / reverse-index tables from the tip MIDX (root or chain tip).

load_midx_reuse_tables_from_path

Load reuse tables from one on-disk MIDX layer (multi-pack-index or multi-pack-index.d/…midx).

midx_checksum_hex

Trailing 40-character SHA-1 hex of the active MIDX (root or chain tip).

midx_lookup_pack_and_offset

Look up which pack and in-pack offset holds oid according to the active MIDX.

midx_lookup_pack_and_offset_opt

Look up which pack and in-pack offset holds oid when listed in the active MIDX.

midx_oid_listed_in_tip

Returns whether oid appears in the active MIDX OID table for objects_dir.

midx_sidecar_path_for_midx_file

Resolve a specific MIDX layer file by its lowercase hex checksum. Searches the incremental chain (multi-pack-index.d/multi-pack-index-<hash>.midx) and the single-file root MIDX. Returns None when no layer matches that checksum. Sidecar path multi-pack-index-<hash>.<ext> in the same directory as midx_path.

read_midx_btmp_ranges

Read per-pack (bitmap_pos, bitmap_nr) from the active MIDX BTMP chunk.

read_midx_objects

Read the tip MIDX and return (pack_names, objects), where each object names the pack it is attributed to (pack_int_id). Mirrors the per-object nth_midxed_pack_int_id iteration in Git used by expire/repack.

read_midx_pack_idx_names

Pack index basenames stored in the active tip MIDX’s pack-names chunk.

read_midx_preferred_idx_name

read_midx_preferred_idx_name function.

resolve_midx_bitmap_layer

Newest chain layer (or root MIDX) that has a non-empty .bitmap sidecar beside its MIDX file.

resolve_midx_layer_path

resolve_midx_layer_path function.

resolve_tip_midx_path

resolve_tip_midx_path function.

try_read_info_via_midx

Like try_read_object_via_midx, but returns ObjectInfo without inflating object bodies.

try_read_info_via_midx_with_diagnostics

Like try_read_info_via_midx, emitting recoverable MIDX warnings through diagnostics.

try_read_object_via_midx

When core.multiPackIndex is enabled, try to read oid from the active MIDX in objects_dir.

try_read_object_via_midx_with_diagnostics

Like try_read_object_via_midx, emitting recoverable MIDX warnings through diagnostics.

validate_midx_referenced_packs

Validate existing pack indexes named by the active MIDX once per prepared chain view.

validate_midx_referenced_packs_with_diagnostics

Like validate_midx_referenced_packs, emitting warnings through diagnostics.

verify_midx

Full multi-pack-index verification, mirroring verify_midx_file in git/midx.c plus the die()/error() conditions in load_multi_pack_index. On any problem returns the list of error lines (without error:/fatal: prefixes) in the order Git emits them; an empty list means the MIDX is valid.

write_multi_pack_index

write_multi_pack_index function.

write_multi_pack_index_with_options

Write multi-pack-index with optional preferred pack, bitmap sidecars, and incremental chain.