[PATCH v2 00/10] odb: make consistency checks pluggable

Hi,

this patch series makes object database consistency checks pluggable.

This series is built on top of 2c3adbb2c4 (The 18th batch, 2026-08-24)
with the following two dependencsie merged into it:

  - ps/odb-eagerly-load-alternates at 0076dc9f81 (odb: drop
    `alternates_db` field, 2026-08-17)

  - ps/odb-pluggable-pack-generation at 5176dd3d05 (bundle: generate
    packfiles via the object database, 2026-08-21)

Changes in v2:
  - Some commit message improvements.
  - Link to v1: https://patch.msgid.link/20260825-pks-odb-source-fsck-v1-0-b756de0bf24f@pks.im

Thanks!

Patrick

---
Patrick Steinhardt (10):
      builtin/fsck: use `fsck_obj_buffer()` when checking loose objects
      builtin/fsck: merge `fsck_obj_buffer()` and `fsck_obj()`
      builtin/fsck: de-globalize option handling
      builtin/fsck: don't check alternates with "--no-full"
      odb: provide infrastructure for pluggable fsck checks
      builtin/fsck: move packfile verification into the packed source
      builtin/fsck: move reverse index verification into the packed source
      builtin/fsck: move bitmap verification into the packed source
      builtin/fsck: move multi-pack index verification into the packed source
      builtin/fsck: move loose object verification into the loose source

 builtin/fsck.c                | 296 ++++++++----------------------------------
 odb.c                         |   9 ++
 odb.h                         |  33 +++++
 odb/source-files.c            |  13 ++
 odb/source-inmemory.c         |   8 ++
 odb/source-loose.c            |  92 +++++++++++++
 odb/source-packed.c           | 117 +++++++++++++++++
 odb/source.h                  |  21 +++
 pack-bitmap.c                 |  26 ++--
 pack-bitmap.h                 |   2 +-
 t/t1450-fsck.sh               |   5 +
 t/t5319-multi-pack-index.sh   |  13 ++
 t/t5325-reverse-index.sh      |   8 ++
 t/t5326-multi-pack-bitmaps.sh |  10 +-
 14 files changed, 394 insertions(+), 259 deletions(-)

Range-diff versus v1:

 1:  cf49376600 !  1:  1aec903546 builtin/fsck: use `fsck_obj_buffer()` when checking loose objects
    @@ Commit message
     
         When checking loose objects we manually parse the object buffer we have
         read from the on-disk file, mark the object and then call `fsck_obj()`.
    -    Almost the exact same steps are also performed by `fsck_obj_buffer()`.
    +    The exact same steps are also performed by `fsck_obj_buffer()`.
     
         Stop open-coding this logic and call `fsck_obj_buffer()` instead.
     
 2:  da2ca27041 !  2:  3804f0339e builtin/fsck: merge `fsck_obj_buffer()` and `fsck_obj()`
    @@ Commit message
         Furthermore, `fsck_obj()` has no callers other than `fsck_obj_buffer()`.
     
         Refactor the code by merging those two functions. This makes it obvious
    -    which function does what, and it allows us to get rid of the early in
    -    `fsck_obj()` in case `SEEN` is set as the only caller unconditionally
    -    clears that bit before calling it anyway.
    +    which function does what, and it allows us to get rid of the early
    +    return in `fsck_obj()` in case `SEEN` is set as the only caller
    +    unconditionally clears that bit before calling it anyway.
     
         Signed-off-by: Patrick Steinhardt [off-list ref]
     
 3:  a24506f55e =  3:  b2cb9032cf builtin/fsck: de-globalize option handling
 4:  f6a407efd0 =  4:  10ee3b8baf builtin/fsck: don't check alternates with "--no-full"
 5:  31841a1f05 =  5:  1e65eec60e odb: provide infrastructure for pluggable fsck checks
 6:  2cd6d71983 =  6:  0b8cf751aa builtin/fsck: move packfile verification into the packed source
 7:  c0559f1820 =  7:  3a38a75549 builtin/fsck: move reverse index verification into the packed source
 8:  96ae1ce3c6 !  8:  dd3a4c6cea builtin/fsck: move bitmap verification into the packed source
    @@ Commit message
         instead use the generic `ERROR_OBJECT` bit.
     
         Note that this change also adapts `verify_bitmap_files()` to be
    -    focussed on a single "packed" source instead of verifying bitmaps from
    +    focused on a single "packed" source instead of verifying bitmaps from
         all sources. This change is required as we already know to loop around
         the sources in `odb_fsck()` itself.
     
 9:  4721f4b4ba =  9:  90ada56b7f builtin/fsck: move multi-pack index verification into the packed source
10:  0b36829fd9 = 10:  b0f6fccae8 builtin/fsck: move loose object verification into the loose source

---
base-commit: 6b08999fb1b3ad0bad04d492dc206ad42839e274
change-id: 20260810-pks-odb-source-fsck-e64772c7ee5f