Commit Graph

128 Commits (ec902f476980d7dda84301f64dbab1d7c85a4082)

Author SHA1 Message Date
Junio C Hamano 36d8035d27 Merge branch 'ps/object-file-cleanup'
Code clean-up.

* ps/object-file-cleanup:
  object-store: merge "object-store-ll.h" and "object-store.h"
  object-store: remove global array of cached objects
  object: split out functions relating to object store subsystem
  object-file: drop `index_blob_stream()`
  object-file: split up concerns of `HASH_*` flags
  object-file: split out functions relating to object store subsystem
  object-file: move `xmmap()` into "wrapper.c"
  object-file: move `git_open_cloexec()` to "compat/open.c"
  object-file: move `safe_create_leading_directories()` into "path.c"
  object-file: move `mkdir_in_gitdir()` into "path.c"
2025-04-24 17:25:33 -07:00
Junio C Hamano ee847e0034 Merge branch 'ps/object-wo-the-repository'
The object layer has been updated to take an explicit repository
instance as a parameter in more code paths.

* ps/object-wo-the-repository:
  hash: stop depending on `the_repository` in `null_oid()`
  hash: fix "-Wsign-compare" warnings
  object-file: split out logic regarding hash algorithms
  delta-islands: stop depending on `the_repository`
  object-file-convert: stop depending on `the_repository`
  pack-bitmap-write: stop depending on `the_repository`
  pack-revindex: stop depending on `the_repository`
  pack-check: stop depending on `the_repository`
  environment: move access to "core.bigFileThreshold" into repo settings
  pack-write: stop depending on `the_repository` and `the_hash_algo`
  object: stop depending on `the_repository`
  csum-file: stop depending on `the_repository`
2025-04-15 13:50:15 -07:00
Patrick Steinhardt 68cd492a3e object-store: merge "object-store-ll.h" and "object-store.h"
The "object-store-ll.h" header has been introduced to keep transitive
header dependendcies and compile times at bay. Now that we have created
a new "object-store.c" file though we can easily move the last remaining
additional bit of "object-store.h", the `odb_path_map`, out of the
header.

Do so. As the "object-store.h" header is now equivalent to its low-level
alternative we drop the latter and inline it into the former.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-04-15 08:24:37 -07:00
Taylor Blau 27afc272c4 midx: implement writing incremental MIDX bitmaps
Now that the pack-bitmap machinery has learned how to read and interact
with an incremental MIDX bitmap, teach the pack-bitmap-write.c machinery
(and relevant callers from within the MIDX machinery) to write such
bitmaps.

The details for doing so are mostly straightforward. The main changes
are as follows:

  - find_object_pos() now makes use of an extra MIDX parameter which is
    used to locate the bit positions of objects which are from previous
    layers (and thus do not exist in the current layer's pack_order
    field).

    (Note also that the pack_order field is moved into struct
    write_midx_context to further simplify the callers for
    write_midx_bitmap()).

  - bitmap_writer_build_type_index() first determines how many objects
    precede the current bitmap layer and offsets the bits it sets in
    each respective type-level bitmap by that amount so they can be OR'd
    together.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Acked-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-21 04:34:16 -07:00
Patrick Steinhardt 1a6768d1dd pack-bitmap-write: stop depending on `the_repository`
There are multiple sites in "pack-bitmap-write.c" where we use the
global `the_repository` variable, either explicitly or implicitly by
using `the_hash_algo`.

Refactor the code so that the `struct bitmap_writer` stores the
repository it is getting initialized with. Like this, we can adapt
callsites that use `the_repository` to instead use the repository
provided by the writer.

Remove the `USE_THE_REPOSITORY_VARIABLE` define.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-10 13:16:19 -07:00
Patrick Steinhardt 228457c9d9 csum-file: stop depending on `the_repository`
There are multiple sites in "csum-file.c" where we use the global
`the_repository` variable, either explicitly or implicitly by using
`the_hash_algo`.

Refactor the code to stop using `the_repository` by adapting functions
to receive required data as parameters. Adapt callsites accordingly by
either using `the_repository->hash_algo`, or by using a context-provided
hash algorithm in case the subsystem already got rid of its dependency
on `the_repository`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-10 13:16:18 -07:00
Patrick Steinhardt 028f618658 path: adjust last remaining users of `the_repository`
With the preceding refactorings we now only have a couple of implicit
users of `the_repository` left in the "path" subsystem, all of which
depend on global state via `calc_shared_perm()`. Make the dependency on
`the_repository` explicit by passing the repo as a parameter instead and
adjust callers accordingly.

Note that this change bubbles up into a couple of subsystems that were
previously declared as free from `the_repository`. Instead of marking
all of them as `the_repository`-dependent again, we instead use the
repository that is available in the calling context. There are three
exceptions though with "copy.c", "pack-write.c" and "tempfile.c".
Adjusting these would require us to adapt callsites all over the place,
so this is left for a future iteration.

Mark "path.c" as free from `the_repository`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-02-28 13:54:11 -08:00
Patrick Steinhardt 1f7e6478dc progress: stop using `the_repository`
Stop using `the_repository` in the "progress" subsystem by passing in a
repository when initializing `struct progress`. Furthermore, store a
pointer to the repository in that struct so that we can pass it to the
trace2 API when logging information.

Adjust callers accordingly by using `the_repository`. While there may be
some callers that have a repository available in their context, this
trivial conversion allows for easier verification and bubbles up the use
of `the_repository` by one level.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-18 10:44:30 -08:00
Patrick Steinhardt 41f43b8243 global: mark code units that generate warnings with `-Wsign-compare`
Mark code units that generate warnings with `-Wsign-compare`. This
allows for a structured approach to get rid of all such warnings over
time in a way that can be easily measured.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-06 20:20:02 +09:00
Patrick Steinhardt 7f97266ee1 pack-bitmap-write: fix leaking OID array
Fix a leaking OID array in `write_pseudo_merges()`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:07 -07:00
Patrick Steinhardt 55e563a90c pseudo-merge: fix various memory leaks
Fix various memory leaks hit by the pseudo-merge machinery. These leaks
are exposed by t5333, but plugging them does not yet make the whole test
suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:06 -07:00
Junio C Hamano 2ff26d2286 Merge branch 'jk/drop-unused-parameters'
Drop unused parameters from functions.

* jk/drop-unused-parameters:
  diff-lib: drop unused index argument from get_stat_data()
  ref-filter: drop unused parameters from email_atom_option_parser()
  pack-bitmap: drop unused parameters from select_pseudo_merges()
  pack-bitmap: load writer config from repository parameter
  refs: drop some unused parameters from create_symref_lock()
2024-08-26 11:32:22 -07:00
Jeff King 4756494504 pack-bitmap: drop unused parameters from select_pseudo_merges()
We take the array of indexed_commits (and its length), but there's no
need. The selection is based on ref reachability, not the linearized set
of commits we're packing.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-17 09:44:41 -07:00
Jeff King ecc6fa9ae9 pack-bitmap: load writer config from repository parameter
In bitmap_writer_init(), we take a repository parameter but ever look at
it. Most of the initialization here is independent of the repository,
but we do load some config. So let's pass the repo we get down to
load_pseudo_merges_from_config(), which in turn can use repo_config(),
rather than depending on the_repository via git_config().

The outcome is the same, since all callers pass in the_repository
anyway. But it takes us a step closer to getting rid of the global, and
as a bonus it silences an unused parameter warning.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-17 09:44:40 -07:00
Taylor Blau 187504f9b2 pack-bitmap-write.c: select pseudo-merges even for small bitmaps
Ordinarily, the pack-bitmap machinery will select some subset of
reachable commits to receive bitmaps. But when there are fewer than 100
commits indexed in the first place, they will all receive bitmaps as a
special case.

When this happens, pseudo-merges are not generated, making it impossible
to test pseudo-merge corner cases with fewer than 100 commits.

Select pseudo-merges even for bitmaps with fewer than 100 commits to
make such testing easier. In practice, this should not make a difference
to non-testing bitmaps, as they are unlikely to be used when a
repository has so few commits to begin with.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-15 11:25:02 -07:00
Taylor Blau 11a08e8332 pack-bitmap: drop redundant args from `bitmap_writer_finish()`
In a similar fashion as the previous commit, drop a redundant argument
from the `bitmap_writer_finish()` function.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-15 11:23:15 -07:00
Taylor Blau f00dda4849 pack-bitmap: drop redundant args from `bitmap_writer_build()`
In a similar fashion as the previous commit, drop a redundant argument
from the `bitmap_writer_build()` function.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-15 11:22:27 -07:00
Taylor Blau 125ee4ae80 pack-bitmap: drop redundant args from `bitmap_writer_build_type_index()`
The previous commit ensures that the bitmap_writer's "to_pack" field is
initialized early on, so the "to_pack" and "index_nr" arguments to
`bitmap_writer_build_type_index()` are redundant.

Drop them and adjust the callers accordingly.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-15 11:20:24 -07:00
Taylor Blau 01e9d12939 pack-bitmap: initialize `bitmap_writer_init()` with packing_data
In order to determine its object order, the pack-bitmap machinery keeps
a 'struct packing_data' corresponding to the pack or pseudo-pack (when
writing a MIDX bitmap) being written.

The to_pack field is provided to the bitmap machinery by callers of
bitmap_writer_build() and assigned to the bitmap_writer struct at that
point.

But a subsequent commit will want to have access to that data earlier on
during commit selection. Prepare for that by adding a 'to_pack' argument
to 'bitmap_writer_init()', and initializing the field during that
function.

Subsequent commits will clean up other functions which take
now-redundant arguments (like nr_objects, which is equivalent to
pdata->objects_nr, or pdata itself).

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-15 11:18:04 -07:00
Junio C Hamano 7b472da915 Merge branch 'ps/use-the-repository'
A CPP macro USE_THE_REPOSITORY_VARIABLE is introduced to help
transition the codebase to rely less on the availability of the
singleton the_repository instance.

* ps/use-the-repository:
  hex: guard declarations with `USE_THE_REPOSITORY_VARIABLE`
  t/helper: remove dependency on `the_repository` in "proc-receive"
  t/helper: fix segfault in "oid-array" command without repository
  t/helper: use correct object hash in partial-clone helper
  compat/fsmonitor: fix socket path in networked SHA256 repos
  replace-object: use hash algorithm from passed-in repository
  protocol-caps: use hash algorithm from passed-in repository
  oidset: pass hash algorithm when parsing file
  http-fetch: don't crash when parsing packfile without a repo
  hash-ll: merge with "hash.h"
  refs: avoid include cycle with "repository.h"
  global: introduce `USE_THE_REPOSITORY_VARIABLE` macro
  hash: require hash algorithm in `empty_tree_oid_hex()`
  hash: require hash algorithm in `is_empty_{blob,tree}_oid()`
  hash: make `is_null_oid()` independent of `the_repository`
  hash: convert `oidcmp()` and `oideq()` to compare whole hash
  global: ensure that object IDs are always padded
  hash: require hash algorithm in `oidread()` and `oidclr()`
  hash: require hash algorithm in `hasheq()`, `hashcmp()` and `hashclr()`
  hash: drop (mostly) unused `is_empty_{blob,tree}_sha1()` functions
2024-07-02 09:59:00 -07:00
Patrick Steinhardt e7da938570 global: introduce `USE_THE_REPOSITORY_VARIABLE` macro
Use of the `the_repository` variable is deprecated nowadays, and we
slowly but steadily convert the codebase to not use it anymore. Instead,
callers should be passing down the repository to work on via parameters.

It is hard though to prove that a given code unit does not use this
variable anymore. The most trivial case, merely demonstrating that there
is no direct use of `the_repository`, is already a bit of a pain during
code reviews as the reviewer needs to manually verify claims made by the
patch author. The bigger problem though is that we have many interfaces
that implicitly rely on `the_repository`.

Introduce a new `USE_THE_REPOSITORY_VARIABLE` macro that allows code
units to opt into usage of `the_repository`. The intent of this macro is
to demonstrate that a certain code unit does not use this variable
anymore, and to keep it from new dependencies on it in future changes,
be it explicit or implicit

For now, the macro only guards `the_repository` itself as well as
`the_hash_algo`. There are many more known interfaces where we have an
implicit dependency on `the_repository`, but those are not guarded at
the current point in time. Over time though, we should start to add
guards as required (or even better, just remove them).

Define the macro as required in our code units. As expected, most of our
code still relies on the global variable. Nearly all of our builtins
rely on the variable as there is no way yet to pass `the_repository` to
their entry point. For now, declare the macro in "biultin.h" to keep the
required changes at least a little bit more contained.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-14 10:26:33 -07:00
Patrick Steinhardt f4836570a7 hash: require hash algorithm in `hasheq()`, `hashcmp()` and `hashclr()`
Many of our hash functions have two variants, one receiving a `struct
git_hash_algo` and one that derives it via `the_repository`. Adapt all
of those functions to always require the hash algorithm as input and
drop the variants that do not accept one.

As those functions are now independent of `the_repository`, we can move
them from "hash.h" to "hash-ll.h".

Note that both in this and subsequent commits in this series we always
just pass `the_repository->hash_algo` as input even if it is obvious
that there is a repository in the context that we should be using the
hash from instead. This is done to be on the safe side and not introduce
any regressions. All callsites should eventually be amended to use a
repo passed via parameters, but this is outside the scope of this patch
series.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-14 10:26:32 -07:00
Taylor Blau 7252d9a036 pseudo-merge: implement support for finding existing merges
This patch implements support for reusing existing pseudo-merge commits
when writing bitmaps when there is an existing pseudo-merge bitmap which
has exactly the same set of parents as one that we are about to write.

Note that unstable pseudo-merges are likely to change between
consecutive repacks, and so are generally poor candidates for reuse.
However, stable pseudo-merges (see the configuration option
'bitmapPseudoMerge.<name>.stableThreshold') are by definition unlikely
to change between runs (as they represent long-running branches).

Because there is no index from a *set* of pseudo-merge parents to a
matching pseudo-merge bitmap, we have to construct the bitmap
corresponding to the set of parents for each pending pseudo-merge commit
and see if a matching bitmap exists.

This is technically quadratic in the number of pseudo-merges, but is OK
in practice for a couple of reasons:

  - non-matching pseudo-merge bitmaps are rejected quickly as soon as
    they differ in a single bit

  - already-matched pseudo-merge bitmaps are discarded from subsequent
    rounds of search

  - the number of pseudo-merges is generally small, even for large
    repositories

In order to do this, implement (a) a function that finds a matching
pseudo-merge given some uncompressed bitset describing its parents, (b)
a function that computes the bitset of parents for a given pseudo-merge
commit, and (c) call that function before computing the set of reachable
objects for some pending pseudo-merge.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-24 11:40:44 -07:00
Taylor Blau 53ea3ec479 pack-bitmap-write.c: write pseudo-merge table
Now that the pack-bitmap writer machinery understands how to select and
store pseudo-merge commits, teach it how to write the new optional
pseudo-merge .bitmap extension.

No readers yet exist for this new extension to the .bitmap format. The
following commits will take any preparatory step(s) necessary before
then implementing the routines necessary to read this new table.

In the meantime, the new `write_pseudo_merges()` function implements
writing this new format as described by a previous commit in
Documentation/technical/bitmap-format.txt.

Writing this table is fairly straightforward and consists of a few
sub-components:

  - a pair of bitmaps for each pseudo-merge (one for the pseudo-merge
    "parents", and another for the objects reachable from those parents)

  - for each commit, the offset of either (a) the pseudo-merge it
    belongs to, or (b) an extended lookup table if it belongs to >1
    pseudo-merge groups

  - if there are any commits belonging to >1 pseudo-merge group, the
    extended lookup tables (which each consist of the number of
    pseudo-merge groups a commit appears in, and then that many 4-byte
    unsigned )

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-24 11:40:42 -07:00
Taylor Blau faf558b23e pseudo-merge: implement support for selecting pseudo-merge commits
Teach the new pseudo-merge machinery how to select non-bitmapped commits
for inclusion in different pseudo-merge group(s) based on a handful of
criteria.

Note that the selected pseudo-merge commits aren't actually used or
written anywhere yet. This will be done in the following commit.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-24 11:40:42 -07:00
Taylor Blau c059c8795e pack-bitmap: make `bitmap_writer_push_bitmapped_commit()` public
The pseudo-merge selection code will be added in a subsequent commit,
and will need a way to push the allocated commit structures into the
bitmap writer from a separate compilation unit.

Make the `bitmap_writer_push_bitmapped_commit()` function part of the
pack-bitmap.h header in order to make this possible.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-24 11:40:42 -07:00
Taylor Blau 245a7f2e01 pack-bitmap: implement `bitmap_writer_has_bitmapped_object_id()`
Prepare to implement pseudo-merge bitmap selection by implementing a
necessary new function, `bitmap_writer_has_bitmapped_object_id()`.

This function returns whether or not the bitmap_writer selected the
given object ID for bitmapping. This will allow the pseudo-merge
machinery to reject candidates for pseudo-merges if they have already
been selected as an ordinary bitmap tip.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-24 11:40:42 -07:00
Taylor Blau 0d41b18317 pack-bitmap-write: support storing pseudo-merge commits
Prepare to write pseudo-merge bitmaps by annotating individual bitmapped
commits (which are represented by the `bitmapped_commit` structure) with
an extra bit indicating whether or not they are a pseudo-merge.

In subsequent commits, pseudo-merge bitmaps will be generated by
allocating a fake commit node with parents covering the full set of
commits represented by the pseudo-merge bitmap. These commits will be
added to the set of "selected" commits as usual, but will be written
specially instead of being included with the rest of the selected
commits.

Mechanically speaking, there are two parts of this change:

  - The bitmapped_commit struct gets a new bit indicating whether it is
    a pseudo-merge, or an ordinary commit selected for bitmaps.

  - A handful of changes to only write out the non-pseudo-merge commits
    when enumerating through the selected array (see the new
    `bitmap_writer_selected_nr()` function). Pseudo-merge commits appear
    after all non-pseudo-merge commits, so it is safe to enumerate
    through the selected array like so:

        for (i = 0; i < bitmap_writer_selected_nr(); i++)
          if (writer.selected[i].pseudo_merge)
            BUG("unexpected pseudo-merge");

    without encountering the BUG().

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-24 11:40:42 -07:00
Taylor Blau 4722e06edc pack-bitmap: move some initialization to `bitmap_writer_init()`
The pack-bitmap-writer machinery uses a oidmap (backed by khash.h) to
map from commits selected for bitmaps (by OID) to a bitmapped_commit
structure (containing the bitmap itself, among other things like its XOR
offset, etc.)

This map was initialized at the end of `bitmap_writer_build()`. New
entries are added in `pack-bitmap-write.c::store_selected()`, which is
called by the bitmap_builder machinery (which is responsible for
traversing history and generating the actual bitmaps).

Reorganize when this field is initialized and when entries are added to
it so that we can quickly determine whether a commit is a candidate for
pseudo-merge selection, or not (since it was already selected to receive
a bitmap, and thus storing it in a pseudo-merge would be redundant).

The changes are as follows:

  - Introduce a new `bitmap_writer_init()` function which initializes
    the `writer.bitmaps` field (instead of waiting until the end of
    `bitmap_writer_build()`).

  - Add map entries in `push_bitmapped_commit()` (which is called via
    `bitmap_writer_select_commits()`) with OID keys and NULL values to
    track whether or not we *expect* to write a bitmap for some given
    commit.

  - Validate that a NULL entry is found matching the given key when we
    store a selected bitmap.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-24 11:40:41 -07:00
Taylor Blau 85f360fee5 pack-bitmap: introduce `bitmap_writer_free()`
Now that there is clearer memory ownership around the bitmap_writer
structure, introduce a bitmap_writer_free() function that callers may
use to free any memory associated with their instance of the
bitmap_writer structure.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-15 06:53:46 -07:00
Taylor Blau f25e1f2a4d pack-bitmap-write.c: avoid uninitialized 'write_as' field
Prepare to free() memory associated with bitmapped_commit structs by
zero'ing the 'write_as' field.

In ideal cases, it is fine to do something like:

    for (i = 0; i < writer->selected_nr; i++) {
        struct bitmapped_commit *bc = &writer->selected[i];
        if (bc->write_as != bc->bitmap)
            ewah_free(bc->write_as);
        ewah_free(bc->bitmap);
    }

but if not all of the 'write_as' fields were populated (e.g., because
the packing_data given does not form a reachability closure), then we
may attempt to free uninitialized memory.

Guard against this by preemptively zero'ing this field just in case.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-15 06:52:32 -07:00
Taylor Blau 9675b06917 pack-bitmap: drop unused `max_bitmaps` parameter
The `max_bitmaps` parameter in `bitmap_writer_select_commits()` was
introduced back in 7cc8f97108 (pack-objects: implement bitmap writing,
2013-12-21), making it original to the bitmap implementation in Git
itself.

When that patch was merged via 0f9e62e084 (Merge branch
'jk/pack-bitmap', 2014-02-27), its sole caller in builtin/pack-objects.c
passed a value of "-1" for `max_bitmaps`, indicating no limit.

Since then, the only other caller (in midx.c, added via c528e17966
(pack-bitmap: write multi-pack bitmaps, 2021-08-31)) also uses a value
of "-1" for `max_bitmaps`.

Since no callers have needed a finite limit for the `max_bitmaps`
parameter in the nearly decade that has passed since 0f9e62e084, let's
remove the parameter and any dead pieces of code connected to it.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-15 06:52:32 -07:00
Taylor Blau 07647c92ff pack-bitmap: avoid use of static `bitmap_writer`
The pack-bitmap machinery uses a structure called 'bitmap_writer' to
collect the data necessary to write out .bitmap files. Since its
introduction in 7cc8f97108 (pack-objects: implement bitmap writing,
2013-12-21), there has been a single static bitmap_writer structure,
which is responsible for all bitmap writing-related operations.

In practice, this is OK, since we are only ever writing a single .bitmap
file in a single process (e.g., `git multi-pack-index write --bitmap`,
`git pack-objects --write-bitmap-index`, `git repack -b`, etc.).

However, having a single static variable makes issues like data
ownership unclear, when to free variables, what has/hasn't been
initialized unclear.

Refactor this code to be written in terms of a given bitmap_writer
structure instead of relying on a static global.

Note that this exposes the structure definition of the bitmap_writer at
the pack-bitmap.h level. We could work around this by, e.g., forcing
callers to declare their writers as:

    struct bitmap_writer *writer;
    bitmap_writer_init(&bitmap_writer);

and then declaring `bitmap_writer_init()` as taking in a double-pointer
like so:

    void bitmap_writer_init(struct bitmap_writer **writer);

which would avoid us having to expose the definition of the structure
itself. This patch takes a different approach, since future patches
(like for the ongoing pseudo-merge bitmaps work) will want to modify the
innards of this structure (in the previous example, via pseudo-merge.c).

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-15 06:52:32 -07:00
Taylor Blau 94830fcacc pack-bitmap-write.c: move commit_positions into commit_pos fields
In 7cc8f97108 (pack-objects: implement bitmap writing, 2013-12-21), the
bitmapped_commit struct was introduced, including the 'commit_pos'
field, which has been unused ever since its introduction more than a
decade ago.

Instead, we have used the nearby `commit_positions` array leaving the
bitmapped_commit struct with an unused 4-byte field.

We could drop the `commit_pos` field as unused, and continue to store
the values in the auxiliary array. But we could also drop the array and
store the data for each bitmapped_commit struct inside of the structure
itself, which is what this patch does.

In any spot that we previously read `commit_positions[i]`, we can now
instead read `writer.selected[i].commit_pos`. There are a few spots that
need changing as a result:

  - write_selected_commits_v1() is a simple transformation, since we're
    just reading the field. As a result, the function no longer needs an
    explicit argument to pass the commit_positions array.

  - write_lookup_table() also no longer needs the explicit
    commit_positions array passed in as an argument. But it still needs
    to sort an array of indices into the writer.selected array to read
    them in commit_pos order, so table_cmp() is adjusted accordingly.

  - bitmap_writer_finish() no longer needs to allocate, populate, and
    free the commit_positions table. Instead, we can just write the data
    directly into each struct bitmapped_commit.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-15 06:52:31 -07:00
Junio C Hamano 1002f28a52 Merge branch 'eb/hash-transition'
Work to support a repository that work with both SHA-1 and SHA-256
hash algorithms has started.

* eb/hash-transition: (30 commits)
  t1016-compatObjectFormat: add tests to verify the conversion between objects
  t1006: test oid compatibility with cat-file
  t1006: rename sha1 to oid
  test-lib: compute the compatibility hash so tests may use it
  builtin/ls-tree: let the oid determine the output algorithm
  object-file: handle compat objects in check_object_signature
  tree-walk: init_tree_desc take an oid to get the hash algorithm
  builtin/cat-file: let the oid determine the output algorithm
  rev-parse: add an --output-object-format parameter
  repository: implement extensions.compatObjectFormat
  object-file: update object_info_extended to reencode objects
  object-file-convert: convert commits that embed signed tags
  object-file-convert: convert commit objects when writing
  object-file-convert: don't leak when converting tag objects
  object-file-convert: convert tag objects when writing
  object-file-convert: add a function to convert trees between algorithms
  object: factor out parse_mode out of fast-import and tree-walk into in object.h
  cache: add a function to read an OID of a specific algorithm
  tag: sign both hashes
  commit: export add_header_signature to support handling signatures on tags
  ...
2024-03-28 14:13:50 -07:00
Junio C Hamano 0fea6b73f1 Merge branch 'tb/multi-pack-verbatim-reuse'
Streaming spans of packfile data used to be done only from a
single, primary, pack in a repository with multiple packfiles.  It
has been extended to allow reuse from other packfiles, too.

* tb/multi-pack-verbatim-reuse: (26 commits)
  t/perf: add performance tests for multi-pack reuse
  pack-bitmap: enable reuse from all bitmapped packs
  pack-objects: allow setting `pack.allowPackReuse` to "single"
  t/test-lib-functions.sh: implement `test_trace2_data` helper
  pack-objects: add tracing for various packfile metrics
  pack-bitmap: prepare to mark objects from multiple packs for reuse
  pack-revindex: implement `midx_pair_to_pack_pos()`
  pack-revindex: factor out `midx_key_to_pack_pos()` helper
  midx: implement `midx_preferred_pack()`
  git-compat-util.h: implement checked size_t to uint32_t conversion
  pack-objects: include number of packs reused in output
  pack-objects: prepare `write_reused_pack_verbatim()` for multi-pack reuse
  pack-objects: prepare `write_reused_pack()` for multi-pack reuse
  pack-objects: pass `bitmapped_pack`'s to pack-reuse functions
  pack-objects: keep track of `pack_start` for each reuse pack
  pack-objects: parameterize pack-reuse routines over a single pack
  pack-bitmap: return multiple packs via `reuse_partial_packfile_from_bitmap()`
  pack-bitmap: simplify `reuse_partial_packfile_from_bitmap()` signature
  ewah: implement `bitmap_is_empty()`
  pack-bitmap: pass `bitmapped_pack` struct to pack-reuse functions
  ...
2024-01-12 16:09:56 -08:00
Elijah Newren eea0e59ffb treewide: remove unnecessary includes in source files
Each of these were checked with
   gcc -E -I. ${SOURCE_FILE} | grep ${HEADER_FILE}
to ensure that removing the direct inclusion of the header actually
resulted in that header no longer being included at all (i.e. that
no other header pulled it in transitively).

...except for a few cases where we verified that although the header
was brought in transitively, nothing from it was directly used in
that source file.  These cases were:
  * builtin/credential-cache.c
  * builtin/pull.c
  * builtin/send-pack.c

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-26 12:04:31 -08:00
Taylor Blau 6cdb67b97d pack-bitmap-write: deep-clear the `bb_commit` slab
The `bb_commit` commit slab is used by the pack-bitmap-write machinery
to track various pieces of bookkeeping used to generate reachability
bitmaps.

Even though we clear the slab when freeing the bitmap_builder struct
(with `bitmap_builder_clear()`), there are still pointers which point to
locations in memory that have not yet been freed, resulting in a leak.

Plug the leak by introducing a suitable `free_fn` for the `struct
bb_commit` type, and make sure it is called on each member of the slab
via the `deep_clear_bb_data()` function.

Note that it is possible for both of the arguments to `bitmap_free()` to
be NULL, but `bitmap_free()` is a noop for NULL arguments, so it is OK
to pass them unconditionally.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-14 14:38:07 -08:00
Eric W. Biederman efed687edc tree-walk: init_tree_desc take an oid to get the hash algorithm
To make it possible for git ls-tree to display the tree encoded
in the hash algorithm of the oid specified to git ls-tree, update
init_tree_desc to take as a parameter the oid of the tree object.

Update all callers of init_tree_desc and init_tree_desc_gently
to pass the oid of the tree object.

Use the oid of the tree object to discover the hash algorithm
of the oid and store that hash algorithm in struct tree_desc.

Use the hash algorithm in decode_tree_entry and
update_tree_entry_internal to handle reading a tree object encoded in
a hash algorithm that differs from the repositories hash algorithm.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-10-02 14:57:40 -07:00
Christian Couder 0e4747ec8b pack-bitmap-write: rebuild using new bitmap when remapping
`git repack` is about to learn a new `--filter=<filter-spec>` option and
we will want to check that this option is incompatible with
`--write-bitmap-index`.

Unfortunately it appears that a test like:

test_expect_success '--filter fails with --write-bitmap-index' '
       test_must_fail \
               env GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP=0 \
               git -C bare.git repack -a -d --write-bitmap-index --filter=blob:none
'

sometimes fail because when rebuilding bitmaps, it appears that we are
reusing existing bitmap information. So instead of detecting that some
objects are missing and erroring out as it should, the
`git repack --write-bitmap-index --filter=...` command succeeds.

Let's fix that by making sure we rebuild bitmaps using new bitmaps
instead of existing ones.

Helped-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-10-02 14:54:30 -07:00
Calvin Wan 91c080dff5 git-compat-util: move alloc macros to git-compat-util.h
alloc_nr, ALLOC_GROW, and ALLOC_GROW_BY are commonly used macros for
dynamic array allocation. Moving these macros to git-compat-util.h with
the other alloc macros focuses alloc.[ch] to allocation for Git objects
and additionally allows us to remove inclusions to alloc.h from files
that solely used the above macros.

Signed-off-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-07-05 11:42:31 -07:00
Elijah Newren a034e9106f object-store-ll.h: split this header out of object-store.h
The vast majority of files including object-store.h did not need dir.h
nor khash.h.  Split the header into two files, and let most just depend
upon object-store-ll.h, while letting the two callers that need it
depend on the full object-store.h.

After this patch:
    $ git grep -h include..object-store | sort | uniq -c
          2 #include "object-store.h"
        129 #include "object-store-ll.h"

Diff best viewed with `--color-moved`.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-06-21 13:39:54 -07:00
Elijah Newren c339932bd8 repository: remove unnecessary include of path.h
This also made it clear that several .c files that depended upon path.h
were missing a #include for it; add the missing includes while at it.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-06-21 13:39:53 -07:00
Elijah Newren 0e312eaa12 diff.h: reduce unnecessary includes
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-24 12:47:33 -07:00
Elijah Newren d4a4f9291d commit.h: reduce unnecessary includes
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-24 12:47:33 -07:00
Elijah Newren d812c3b6a0 treewide: remove cache.h inclusion due to object.h changes
Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-11 08:52:10 -07:00
Junio C Hamano e7dca80692 Merge branch 'ab/remove-implicit-use-of-the-repository' into en/header-split-cache-h
* ab/remove-implicit-use-of-the-repository:
  libs: use "struct repository *" argument, not "the_repository"
  post-cocci: adjust comments for recent repo_* migration
  cocci: apply the "revision.h" part of "the_repository.pending"
  cocci: apply the "rerere.h" part of "the_repository.pending"
  cocci: apply the "refs.h" part of "the_repository.pending"
  cocci: apply the "promisor-remote.h" part of "the_repository.pending"
  cocci: apply the "packfile.h" part of "the_repository.pending"
  cocci: apply the "pretty.h" part of "the_repository.pending"
  cocci: apply the "object-store.h" part of "the_repository.pending"
  cocci: apply the "diff.h" part of "the_repository.pending"
  cocci: apply the "commit.h" part of "the_repository.pending"
  cocci: apply the "commit-reach.h" part of "the_repository.pending"
  cocci: apply the "cache.h" part of "the_repository.pending"
  cocci: add missing "the_repository" macros to "pending"
  cocci: sort "the_repository" rules by header
  cocci: fix incorrect & verbose "the_repository" rules
  cocci: remove dead rule from "the_repository.pending.cocci"
2023-04-04 08:25:52 -07:00
Ævar Arnfjörð Bjarmason ecb5091fd4 cocci: apply the "commit.h" part of "the_repository.pending"
Apply the part of "the_repository.pending.cocci" pertaining to
"commit.h".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-28 07:36:45 -07:00
Elijah Newren ec2f026961 csum-file.h: remove unnecessary inclusion of cache.h
With the change in the last commit to move several functions to
write-or-die.h, csum-file.h no longer needs to include cache.h.
However, removing that include forces several other C files, which
directly or indirectly dependend upon csum-file.h's inclusion of
cache.h, to now be more explicit about their dependencies.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-21 10:56:55 -07:00
Elijah Newren 32a8f51061 environment.h: move declarations for environment.c functions from cache.h
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-21 10:56:53 -07:00