If a caller to traverse_commit_list() specifies the options for the
--objects flag but does not specify a show_object function pointer, the
result is a segfault. This is currently visible by running 'git bundle
create --objects HEAD'.
We could fix this problem by supplying a no-op callback in
builtin/bundle.c, but that only solves the problem for one builtin,
leaving this segfault open for other callers.
Replace all callers of the show_commit and show_object function pointers
in list-objects.c to call helper functions show_commit() and
show_object() which check that the given context has non-NULL functions
before passing the necessary data. One extra benefit is that it reduces
duplication due to passing ctx->show_data to every caller.
Test that this segfault no longer occurs for 'git bundle'.
Co-authored-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that all consumers of traverse_commit_list_filtered() populate the
'filter' member of 'struct rev_info', we can drop that parameter from
the method prototype to simplify things. In addition, the only thing
different now between traverse_commit_list_filtered() and
traverse_commit_list() is the presence of the 'omitted' parameter, which
is only non-NULL for one caller. We can consolidate these two methods by
having one call the other and use the simpler form everywhere the
'omitted' parameter would be NULL.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Function `traverse_trees_and_blobs` not only works on trees and blobs,
but also on tags, the function name is somewhat misleading. This commit
rename it to `traverse_non_commits`.
Signed-off-by: Teng Long <dyroneteng@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If an object is already mentioned in a reachability bitmap we are
building, then by definition so are all of the objects it can reach. We
have an optimization to stop traversing commits when we see they are
already in the bitmap, but we don't do the same for trees.
It's generally unavoidable to recurse into trees for commits not yet
covered by bitmaps (since most commits generally do have unique
top-level trees). But they usually have subtrees that are shared with
other commits (i.e., all of the subtrees the commit _didn't_ touch). And
some of those commits (and their trees) may be covered by the bitmap.
Usually this isn't _too_ big a deal, because we'll visit those subtrees
only once in total for the whole walk. But if you have a large number of
unbitmapped commits, and if your tree is big, then you may end up
opening a lot of sub-trees for no good reason.
We can use the same optimization we do for commits here: when we are
about to open a tree, see if it's in the bitmap (either the one we are
building, or the "seen" bitmap which covers the UNINTERESTING side of
the bitmap when doing a set-difference).
This works especially well because we'll visit all commits before
hitting any trees. So even in a history like:
A -- B
if "A" has a bitmap on disk but "B" doesn't, we'll already have OR-ed in
the results from A before looking at B's tree (so we really will only
look at trees touched by B).
For most repositories, the timings produced by p5310 are unspectacular.
Here's linux.git:
Test HEAD^ HEAD
--------------------------------------------------------------------
5310.4: simulated clone 6.00(5.90+0.10) 5.98(5.90+0.08) -0.3%
5310.5: simulated fetch 2.98(5.45+0.18) 2.85(5.31+0.18) -4.4%
5310.7: rev-list (commits) 0.32(0.29+0.03) 0.33(0.30+0.03) +3.1%
5310.8: rev-list (objects) 1.48(1.44+0.03) 1.49(1.44+0.05) +0.7%
Any improvement there is within the noise (the +3.1% on test 7 has to be
noise, since we are not recursing into trees, and thus the new code
isn't even run). The results for git.git are likewise uninteresting.
But here are numbers from some other real-world repositories (that are
not public). This one's tree is comparable in size to linux.git, but has
~16k refs (and so less complete bitmap coverage):
Test HEAD^ HEAD
-------------------------------------------------------------------------
5310.4: simulated clone 38.34(39.86+0.74) 33.95(35.53+0.76) -11.5%
5310.5: simulated fetch 2.29(6.31+0.35) 2.20(5.97+0.41) -3.9%
5310.7: rev-list (commits) 0.99(0.86+0.13) 0.96(0.85+0.11) -3.0%
5310.8: rev-list (objects) 11.32(11.04+0.27) 6.59(6.37+0.21) -41.8%
And here's another with a very large tree (~340k entries), and a fairly
large number of refs (~10k):
Test HEAD^ HEAD
-------------------------------------------------------------------------
5310.3: simulated clone 53.83(54.71+1.54) 39.77(40.76+1.50) -26.1%
5310.4: simulated fetch 19.91(20.11+0.56) 19.79(19.98+0.67) -0.6%
5310.6: rev-list (commits) 0.54(0.44+0.11) 0.51(0.43+0.07) -5.6%
5310.7: rev-list (objects) 24.32(23.59+0.73) 9.85(9.49+0.36) -59.5%
This patch provides substantial improvements in these larger cases, and
have any drawbacks for smaller ones (the cost of the bitmap check is
quite small compared to an actual tree traversal).
Note that we have to add a version of revision.c's include_check
callback which handles non-commits. We could possibly consolidate this
into a single callback for all objects types, as there's only one user
of the feature which would need converted (pack-bitmap.c:should_include).
That would in theory let us avoid duplicating any logic. But when I
tried it, the code ended up much worse to read, with lots of repeated
"if it's a commit do this, otherwise do that". Having two separate
callbacks splits that naturally, and matches the existing split of
show_commit/show_object callbacks.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Object filters currently only support filtering blobs or trees based on
some criteria. This commit lays the foundation to also allow filtering
of tags and commits.
No change in behaviour is expected from this commit given that there are
no filters yet for those object types.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move processing of tags into its own function to make the logic easier
to extend when we're going to implement filtering for tags. No change in
behaviour is expected from this commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The object traversal machinery has been optimized not to load tree
objects when we are only interested in commit history.
* jk/list-objects-optim-wo-trees:
list-objects: don't queue root trees unless revs->tree_objects is set
When traverse_commit_list() processes each commit, it queues the
commit's root tree in the pending array. Then, after all commits are
processed, it calls traverse_trees_and_blobs() to walk over the pending
list, calling process_tree() on each. But if revs->tree_objects is not
set, process_tree() just exists immediately!
We can save ourselves some work by not even bothering to queue these
trees in the first place. There are a few subtle points to make:
- we also detect commits with a NULL tree pointer here. But this isn't
an interesting check for broken commits, since the lookup_tree()
we'd have done during commit parsing doesn't actually check that we
have the tree on disk. So we're not losing any robustness.
- besides queueing, we also set the NOT_USER_GIVEN flag on the tree
object. This is used by the traverse_commit_list_filtered() variant.
But if we're not exploring trees, then we won't actually care about
this flag, which is used only inside process_tree() code-paths.
- queueing trees eventually leads to us queueing blobs, too. But we
don't need to check revs->blob_objects here. Even in the current
code, we still wouldn't find those blobs, because we'd never open up
the tree objects to list their contents.
- the user-visible impact to the caller is minimal. The pending trees
are all cleared by the time the function returns anyway, by
traverse_trees_and_blobs(). We do call a show_commit() callback,
which technically could be looking at revs->pending during the
callback. But it seems like a rather unlikely thing to do (if you
want the tree of the current commit, then accessing the tree struct
member is a lot simpler).
So this should be safe to do. Let's look at the benefits:
[before]
Benchmark #1: git -C linux rev-list HEAD >/dev/null
Time (mean ± σ): 7.651 s ± 0.021 s [User: 7.399 s, System: 0.252 s]
Range (min … max): 7.607 s … 7.683 s 10 runs
[after]
Benchmark #1: git -C linux rev-list HEAD >/dev/null
Time (mean ± σ): 7.593 s ± 0.023 s [User: 7.329 s, System: 0.264 s]
Range (min … max): 7.565 s … 7.634 s 10 runs
Not too impressive, but then we're really just avoiding sticking a
pointer into a growable array. But still, I'll take a free 0.75%
speedup.
Let's try it after running "git commit-graph write":
[before]
Benchmark #1: git -C linux rev-list HEAD >/dev/null
Time (mean ± σ): 1.458 s ± 0.011 s [User: 1.199 s, System: 0.259 s]
Range (min … max): 1.447 s … 1.481 s 10 runs
[after]
Benchmark #1: git -C linux rev-list HEAD >/dev/null
Time (mean ± σ): 1.126 s ± 0.023 s [User: 896.5 ms, System: 229.0 ms]
Range (min … max): 1.106 s … 1.181 s 10 runs
Now that's more like it. We saved over 22% of the total time. Part of
that is because the runtime is shorter overall, but the absolute
improvement is also much larger. What's going on?
When we fill in a commit struct using the commit graph, we don't bother
to set the tree pointer, and instead lazy-load it when somebody calls
get_commit_tree(). So we're not only skipping the pointer write to the
pending queue, but we're skipping the lazy-load of the tree entirely.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Encapsulate filter_fn, filter_free_fn, and filter_data into their own
opaque struct.
Due to opaqueness, filter_fn and filter_free_fn can no longer be
accessed directly by users. Currently, all usages of filter_fn are
guarded by a necessary check:
(obj->flags & NOT_USER_GIVEN) && filter_fn
Take the opportunity to include this check into the new function
list_objects_filter__filter_object(), so that we no longer need to write
this check at every caller of the filter function.
Also, the init functions in list-objects-filter.c no longer need to
confusingly return the filter constituents in various places (filter_fn
and filter_free_fn as out parameters, and filter_data as the function's
return value); they can just initialize the "struct filter" passed in.
Helped-by: Jeff Hostetler <git@jeffhostetler.com>
Helped-by: Jonathan Tan <jonathantanmy@google.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the traversal machinery sees a commit without a root tree, it
assumes that the tree was part of a BOUNDARY commit, and quietly ignores
the tree. But it could also be caused by a commit whose root tree is
broken or missing.
Instead, let's die() when we see a NULL root tree. We can differentiate
it from the BOUNDARY case by seeing if the commit was actually parsed.
This covers that case, plus future-proofs us against any others where we
might try to show an unparsed commit.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply similar treatment as the previous commit for non-tree entries,
too.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix one of the cases described in the previous commit where a tree-entry
that is promised to a blob is in fact a non-blob.
When 'lookup_blob()' returns NULL, it is because Git has cached the
requested object as a non-blob. In this case, prevent a SIGSEGV by
'die()'-ing immediately before attempting to dereference the result.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git pack-objects" learned another algorithm to compute the set of
objects to send, that trades the resulting packfile off to save
traversal cost to favor small pushes.
* ds/push-sparse-tree-walk:
pack-objects: create GIT_TEST_PACK_SPARSE
pack-objects: create pack.useSparse setting
revision: implement sparse algorithm
list-objects: consume sparse tree walk
revision: add mark_tree_uninteresting_sparse
The code to walk tree objects has been taught that we may be
working with object names that are not computed with SHA-1.
* bc/tree-walk-oid:
cache: make oidcpy always copy GIT_MAX_RAWSZ bytes
tree-walk: store object_id in a separate member
match-trees: use hashcpy to splice trees
match-trees: compute buffer offset correctly when splicing
tree-walk: copy object ID before use
When creating a pack-file using 'git pack-objects --revs' we provide
a list of interesting and uninteresting commits. For example, a push
operation would make the local topic branch be interesting and the
known remote refs as uninteresting. We want to discover the set of
new objects to send to the server as a thin pack.
We walk these commits until we discover a frontier of commits such
that every commit walk starting at interesting commits ends in a root
commit or unintersting commit. We then need to discover which
non-commit objects are reachable from uninteresting commits. This
commit walk is not changing during this series.
The mark_edges_uninteresting() method in list-objects.c iterates on
the commit list and does the following:
* If the commit is UNINTERSTING, then mark its root tree and every
object it can reach as UNINTERESTING.
* If the commit is interesting, then mark the root tree of every
UNINTERSTING parent (and all objects that tree can reach) as
UNINTERSTING.
At the very end, we repeat the process on every commit directly
given to the revision walk from stdin. This helps ensure we properly
cover shallow commits that otherwise were not included in the
frontier.
The logic to recursively follow trees is in the
mark_tree_uninteresting() method in revision.c. The algorithm avoids
duplicate work by not recursing into trees that are already marked
UNINTERSTING.
Add a new 'sparse' option to the mark_edges_uninteresting() method
that performs this logic in a slightly different way. As we iterate
over the commits, we add all of the root trees to an oidset. Then,
call mark_trees_uninteresting_sparse() on that oidset. Note that we
include interesting trees in this process. The current implementation
of mark_trees_unintersting_sparse() will walk the same trees as
the old logic, but this will be replaced in a later change.
Add a '--sparse' flag in 'git pack-objects' to call this new logic.
Add a new test script t/t5322-pack-objects-sparse.sh that tests this
option. The tests currently demonstrate that the resulting object
list is the same as the old algorithm. This includes a case where
both algorithms pack an object that is not needed by a remote due to
limits on the explored set of trees. When the sparse algorithm is
changed in a later commit, we will add a test that demonstrates a
change of behavior in some cases.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When parsing a tree, we read the object ID directly out of the tree
buffer. This is normally fine, but such an object ID cannot be used with
oidcpy, which copies GIT_MAX_RAWSZ bytes, because if we are using SHA-1,
there may not be that many bytes to copy.
Instead, store the object ID in a separate struct member. Since we can
no longer efficiently compute the path length, store that information as
well in struct name_entry. Ensure we only copy the object ID into the
new buffer if the path length is nonzero, as some callers will pass us
an empty path with no object ID following it, and we will not want to
read past the end of the buffer.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The traversal over tree objects has learned to honor
":(attr:label)" pathspec match, which has been implemented only for
enumerating paths on the filesystem.
* nd/attr-pathspec-in-tree-walk:
tree-walk: support :(attr) matching
dir.c: move, rename and export match_attrs()
pathspec.h: clean up "extern" in function declarations
tree-walk.c: make tree_entry_interesting() take an index
tree.c: make read_tree*() take 'struct repository *'
In order to support :(attr) when matching pathspec on a tree,
tree_entry_interesting() needs to take an index (because
git_check_attr() needs it). This is the preparation step for it. This
also makes it clearer what index we fall back to when looking up
attributes during an unpack-trees operation: the source index.
This also fixes revs->pruning.repo initialization that should have
been done in 2abf350385 (revision.c: remove implicit dependency on
the_index - 2018-09-21). Without it, skip_uninteresting() will
dereference a NULL pointer through this call chain
get_revision(revs)
get_revision_internal
get_revision_1
try_to_simplify_commit
rev_compare_tree
diff_tree_oid(..., &revs->pruning)
ll_diff_tree_oid
diff_tree_paths
ll_diff_tree
skip_uninteresting
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
While at there, since we have access to struct repository now,
eliminate the only the_repository reference in this file.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "rev-list --filter" feature learned to exclude all trees via
"tree:0" filter.
* md/filter-trees:
list-objects: support for skipping tree traversal
filter-trees: code clean-up of tests
list-objects-filter: implement filter tree:0
list-objects-filter-options: do not over-strbuf_init
list-objects-filter: use BUG rather than die
revision: mark non-user-given objects instead
rev-list: handle missing tree objects properly
list-objects: always parse trees gently
list-objects: refactor to process_tree_contents
list-objects: store common func args in struct
The tree:0 filter does not need to traverse the trees that it has
filtered out, so optimize list-objects and list-objects-filter to skip
traversing the trees entirely. Before this patch, we iterated over all
children of the tree, and did nothing for all of them, which was
wasteful.
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, list-objects.c incorrectly treats all root trees of commits
as USER_GIVEN. Also, it would be easier to mark objects that are
non-user-given instead of user-given, since the places in the code
where we access an object through a reference are more obvious than
the places where we access an object that was given by the user.
Resolve these two problems by introducing a flag NOT_USER_GIVEN that
marks blobs and trees that are non-user-given, replacing USER_GIVEN.
(Only blobs and trees are marked because this mark is only used when
filtering objects, and filtering of other types of objects is not
supported yet.)
This fixes a bug in that git rev-list behaved differently from git
pack-objects. pack-objects would *not* filter objects given explicitly
on the command line and rev-list would filter. This was because the two
commands used a different function to add objects to the rev_info
struct. This seems to have been an oversight, and pack-objects has the
correct behavior, so I added a test to make sure that rev-list now
behaves properly.
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Previously, we assumed only blob objects could be missing. This patch
makes rev-list handle missing trees like missing blobs. The --missing=*
and --exclude-promisor-objects flags now work for trees as they already
do for blobs. This is demonstrated in t6112.
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If parsing fails when revs->ignore_missing_links and
revs->exclude_promisor_objects are both false, we print the OID anyway
in the die("bad tree object...") call, so any message printed by
parse_tree_gently() is superfluous.
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This will be used in a follow-up patch to reduce indentation needed when
invoking the logic conditionally. i.e. rather than:
if (foo) {
while (...) {
/* this is very indented */
}
}
we will have:
if (foo)
process_tree_contents(...);
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This will make utility functions easier to create, as done by the next
patch.
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Partial clone support of "git clone" has been updated to correctly
validate the objects it receives from the other side. The server
side has been corrected to send objects that are directly
requested, even if they may match the filtering criteria (e.g. when
doing a "lazy blob" partial clone).
* jt/partial-clone-fsck-connectivity:
clone: check connectivity even if clone is partial
upload-pack: send refs' objects despite "filter"
The conversion to pass "the_repository" and then "a_repository"
throughout the object access API continues.
* sb/object-store-grafts:
commit: allow lookup_commit_graft to handle arbitrary repositories
commit: allow prepare_commit_graft to handle arbitrary repositories
shallow: migrate shallow information into the object parser
path.c: migrate global git_path_* to take a repository argument
cache: convert get_graft_file to handle arbitrary repositories
commit: convert read_graft_file to handle arbitrary repositories
commit: convert register_commit_graft to handle arbitrary repositories
commit: convert commit_graft_pos() to handle arbitrary repositories
shallow: add repository argument to is_repository_shallow
shallow: add repository argument to check_shallow_file_for_update
shallow: add repository argument to register_shallow
shallow: add repository argument to set_alternate_shallow_file
commit: add repository argument to lookup_commit_graft
commit: add repository argument to prepare_commit_graft
commit: add repository argument to read_graft_file
commit: add repository argument to register_commit_graft
commit: add repository argument to commit_graft_pos
object: move grafts to object parser
object-store: move object access functions to object-store.h
A filter line in a request to upload-pack filters out objects regardless
of whether they are directly referenced by a "want" line or not. This
means that cloning with "--filter=blob:none" (or another filter that
excludes blobs) from a repository with at least one ref pointing to a
blob (for example, the Git repository itself) results in output like the
following:
error: missing object referenced by 'refs/tags/junio-gpg-pub'
and if that particular blob is not referenced by a fetched tree, the
resulting clone fails fsck because there is no object from the remote to
vouch that the missing object is a promisor object.
Update both the protocol and the upload-pack implementation to include
all explicitly specified "want" objects in the packfile regardless of
the filter specification.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a repository argument to allow the callers of lookup_tree
to be more specific about which repository to act on. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.
As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a repository argument to allow the callers of lookup_blob
to be more specific about which repository to act on. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.
As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This should make these functions easier to find and cache.h less
overwhelming to read.
In particular, this moves:
- read_object_file
- oid_object_info
- write_object_file
As a result, most of the codebase needs to #include object-store.h.
In this patch the #include is only added to files that would fail to
compile otherwise. It would be better to #include wherever
identifiers from the header are used. That can happen later
when we have better tooling for it.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In anticipation of making trees load lazily, create a Coccinelle
script (contrib/coccinelle/commit.cocci) to ensure that all
references to the 'maybe_tree' member of struct commit are either
mutations or accesses through get_commit_tree() or
get_commit_tree_oid().
Apply the Coccinelle script to create the rest of the patch.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Using the commit-graph file to walk commit history removes the large
cost of parsing commits during the walk. This exposes a performance
issue: lookup_tree() takes a large portion of the computation time,
even when Git never uses those trees.
In anticipation of lazy-loading these trees, rename the 'tree' member
of struct commit to 'maybe_tree'. This serves two purposes: it hints
at the future role of possibly being NULL even if the commit has a
valid tree, and it allows for unambiguous transformation from simple
member access (i.e. commit->maybe_tree) to method access.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In preparation for implementing narrow/partial clone, the machinery
for checking object connectivity used by gc and fsck has been
taught that a missing object is OK when it is referenced by a
packfile specially marked as coming from trusted repository that
promises to make them available on-demand and lazily.
* jh/fsck-promisors:
gc: do not repack promisor packfiles
rev-list: support termination at promisor objects
sha1_file: support lazily fetching missing objects
introduce fetch-object: fetch one promisor object
index-pack: refactor writing of .keep files
fsck: support promisor objects as CLI argument
fsck: support referenced promisor objects
fsck: support refs pointing to promisor objects
fsck: introduce partialclone extension
extension.partialclone: introduce partial clone extension
"git describe" was taught to dig trees deeper to find a
<commit-ish>:<path> that refers to a given blob object.
* sb/describe-blob:
builtin/describe.c: describe a blob
builtin/describe.c: factor out describe_commit
builtin/describe.c: print debug statements earlier
builtin/describe.c: rename `oid` to avoid variable shadowing
revision.h: introduce blob/tree walking in order of the commits
list-objects.c: factor out traverse_trees_and_blobs
t6120: fix typo in test name
Teach rev-list to support termination of an object traversal at any
object from a promisor remote (whether one that the local repo also has,
or one that the local repo knows about because it has another promisor
object that references it).
This will be used subsequently in gc and in the connectivity check used
by fetch.
For efficiency, if an object is referenced by a promisor object, and is
in the local repo only as a non-promisor object, object traversal will
not stop there. This is to avoid building the list of promisor object
references.
(In list-objects.c, the case where obj is NULL in process_blob() and
process_tree() do not need to be changed because those happen only when
there is a conflict between the expected type and the existing object.
If the object doesn't exist, an object will be synthesized, which is
fine.)
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create traverse_commit_list_filtered() and add filtering
interface to allow certain objects to be omitted from the
traversal.
Update traverse_commit_list() to be a wrapper for the above
with a null filter to minimize the number of callers that
needed to be changed.
Object filtering will be used in a future commit by rev-list
and pack-objects for partial clone and fetch to omit unwanted
objects from the result.
traverse_bitmap_commit_list() does not work with filtering.
If a packfile bitmap is present, it will not be used. It
should be possible to extend such support in the future (at
least to simple filters that do not require object pathnames),
but that is beyond the scope of this patch series.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The functionality to list tree objects in the order they were seen
while traversing the commits will be used in one of the next commits,
where we teach `git describe` to describe not only commits, but blobs, too.
The change in list-objects.c is rather minimal as we'll be re-using
the infrastructure put in place of the revision walking machinery. For
example one could expect that add_pending_tree is not called, but rather
commit->tree is directly passed to the tree traversal function. This
however requires a lot more code than just emptying the queue containing
trees after each commit.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
With traverse_trees_and_blobs factored out of the main traverse function,
the next patch can introduce an in-order revision walking with ease.
In the next patch we'll call `traverse_trees_and_blobs` from within the
loop walking the commits, such that we'll have one invocation of that
function per commit. That is why we do not want to have memory allocations
in that function, such as we'd have if we were to use a strbuf locally.
Pass a strbuf from traverse_commit_list into the blob and tree traversing
function as a scratch pad that only needs to be allocated once.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert the lookup_tree function to take a pointer to struct object_id.
The commit was created with manual changes to tree.c, tree.h, and
object.c, plus the following semantic patch:
@@
@@
- lookup_tree(EMPTY_TREE_SHA1_BIN)
+ lookup_tree(&empty_tree_oid)
@@
expression E1;
@@
- lookup_tree(E1.hash)
+ lookup_tree(&E1)
@@
expression E1;
@@
- lookup_tree(E1->hash)
+ lookup_tree(E1)
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert lookup_blob to take a pointer to struct object_id.
The commit was created with manual changes to blob.c and blob.h, plus
the following semantic patch:
@@
expression E1;
@@
- lookup_blob(E1.hash)
+ lookup_blob(&E1)
@@
expression E1;
@@
- lookup_blob(E1->hash)
+ lookup_blob(E1)
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we find a blob at "a/b/c", we currently pass this to
our show_object_fn callbacks as two components: "a/b/" and
"c". Callbacks which want the full value then call
path_name(), which concatenates the two. But this is an
inefficient interface; the path is a strbuf, and we could
simply append "c" to it temporarily, then roll back the
length, without creating a new copy.
So we could improve this by teaching the callsites of
path_name() this trick (and there are only 3). But we can
also notice that no callback actually cares about the
broken-down representation, and simply pass each callback
the full path "a/b/c" as a string. The callback code becomes
even simpler, then, as we do not have to worry about freeing
an allocated buffer, nor rolling back our modification to
the strbuf.
This is theoretically less efficient, as some callbacks
would not bother to format the final path component. But in
practice this is not measurable. Since we use the same
strbuf over and over, our work to grow it is amortized, and
we really only pay to memcpy a few bytes.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the previous commit, we left name_path as a thin wrapper
around a strbuf. This patch drops it entirely. As a result,
every show_object_fn callback needs to be adjusted. However,
none of their code needs to be changed at all, because the
only use was to pass it to path_name(), which now handles
the bare strbuf.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "struct name_path" data is examined in only two places:
we generate it in process_tree(), and we convert it to a
single string in path_name(). Everyone else just passes it
through to those functions.
We can further note that process_tree() already keeps a
single strbuf with the leading tree path, for use with
tree_entry_interesting().
Instead of building a separate name_path linked list, let's
just use the one we already build in "base". This reduces
the amount of code (especially tricky code in path_name()
which did not check for integer overflows caused by deep
or large pathnames).
It is also more efficient in some instances. Any time we
were using tree_entry_interesting, we were building up the
strbuf anyway, so this is an immediate and obvious win
there. In cases where we were not, we trade off storing
"pathname/" in a strbuf on the heap for each level of the
path, instead of two pointers and an int on the stack (with
one pointer into the tree object). On a 64-bit system, the
latter is 20 bytes; so if path components are less than that
on average, this has lower peak memory usage. In practice
it probably doesn't matter either way; we are already
holding in memory all of the tree objects leading up to each
pathname, and for normal-depth pathnames, we are only
talking about hundreds of bytes.
This patch leaves "struct name_path" as a thin wrapper
around the strbuf, to avoid disrupting callbacks. We should
fix them, but leaving it out makes this diff easier to view.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
