Include filekey file attribute when comparing FileSnapshots
Due to finite filesystem timestamp resolution the last modified
timestamp of files cannot detect file changes which happened in the
immediate past (less than one filesystem timer tick ago).
Some filesystems expose unique file identifiers, e.g. inodes in Posix
filesystems which are named filekeys in Java's BasicFileAttributes. Use
them as another means to detect file modifications based on stat
information.
Running git gc on a repository yields a new packfile with the same id as
a packfile which existed before the gc if these packfiles contain the
same set of objects. The content of the old and the new packfile might
differ if a different PackConfig was used when writing the packfile.
Considering filekeys in FileSnapshot may help to detect such packfile
modifications.
Bug: 546891
Change-Id: I711a80328c55e1a31171d540880b8e80ec1fe095
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Measure file timestamp resolution used in FileSnapshot
FileSnapshot.notRacyClean() assumed a worst case filesystem timestamp
resolution of 2.5 sec (FAT has a resolution of 2 sec). Instead measure
timestamp resolution to avoid unnecessary IO caused by false positives
in detecting the racy git problem caused by finite filesystem timestamp
resolution [1].
Cache the measured resolution per FileStore since timestamp resolution
depends on the respective filesystem type. If timestamp resolution
cannot be measured or fails due to an exception fallback to the worst
case FAT timestamp resolution and avoid caching this value.
Add a 10% safety margin in FileSnapshot.notRacyClean(), though running
FsTest.testFsTimestampResolution() 1000 times which is not using a
safety margin didn't fail on Mac using APFS and Java 8, 11, 12.
Measured Java file timestamp resolution: [2]
[1] https://github.com/git/git/blob/master/Documentation/technical/racy-git.txt
[2] https://docs.google.com/spreadsheets/d/1imy0y6WmRqBf0kjCxzxj2X7M50eIVfa7oaUIzEOHmjo
Bug: 546891
Change-Id: I493f3b57b6b306285ffa7d392339d253e5966ab8
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
* fix equals() and hashCode() methods to consider size
* fix toString() to show size
Change-Id: I5485db55eda5110121efd65d86c7166b3b2e93d0
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
GPG: use key fingerprint suffix to compare id for signing key
Check whether the value of the git config user.signingKey is a suffix
of the full fingerprint of the key. This was already used for finding
keys in secring.gpg, but not in pubring.kbx. This mechanism allows a
user to use any unique suffix to identify keys; to avoid needless
collisions it's recommended to use at least the last 16 characters of
the hex representation of the fingerprint, which is the key id.[1]
[1] https://tools.ietf.org/html/rfc4880#section-12.2
Bug: 545673
Change-Id: If6fb4879502b6ee4b8c26c21b2714aeac4e4670c
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
In 7b96bd812e ("UploadPack: Use reachability checker to validate
non-advertised wants", 2019-05-16), a "walk.setRetainBody(false);"
statement was inadvertently deleted. (An earlier version of this commit
had this line in another part of the code and a review comment suggested
to move it back here; the line was then deleted from the other part of
the code but not readded.) Restore this line.
Change-Id: I96ff6106ba9e4eef429388c83e898b3363295f69
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
UploadPack: Use reachability checker to validate non-advertised wants
In "Reachable commit" request validators, we need to check that a "want"
in the request, that hasn't been advertised, is reachable from the refs
visible to the user.
Current code has intermixed the translation of ObjectIds to RevCommits
(and its error handling) with the actual walk, with the delegation to
bitmaps in restricted circunstances.
Refactor the code to make it "flatter" and more readable. Move ObjectIds
to RevCommits translation to its own functions. Use the reachability
checker instead of a newly defined walk.
Before the non-advertised wants were validated with bitmaps only if any
"want" refered to an non-commit. Now they will be validated with bitmaps
also if the "wants" refer all to commits.
Change-Id: Ib925a48cde89672b07a88bba4e24d0457546baff
Signed-off-by: Ivan Frade <ifrade@google.com>
BitmappedReachabilityChecker: Reachability check using bitmaps
The "basic" reachability check walks the graph starting from the tips
marking things as "uninteresting". If the target commit is marked as
"uninteresting" it was reached; it is reachable from those tips.
This requires a lot of walking and can be solved directly with bitmaps.
Most of the time the bitmaps are already calculated or a short walk
away.
This should improve the performance of reachability checks, for example
in Gitiles.
Change-Id: I83d33271f58d95d2dc9ed151967b3eda513c99f7
Signed-off-by: Ivan Frade <ifrade@google.com>
BitmapCalculator: Get the reachability bitmap of a commit
To make reachability checks with bitmaps, we need to get the
reachability bitmap of a commit, which is not always precalculated.
There is already a class returning such bitmap (BitmapWalker) but it
does too much unnecessary work: it calculates ALL reachable objects from
a commit (i.e. including trees and blobs), when for reachability the
commits are just enough.
Introduce BitmapCalculator to get the bitmap of a commit: either because
it is precalculated or generating it with a walk only over commits.
Change-Id: Ibb6c78affe9eeaf1fa362a06daf4fd2d91c1caea
Signed-off-by: Ivan Frade <ifrade@google.com>
ReachabilityChecker: Default implementation with a RevWalk
It is common to check if a certain commit is reachable from some
starting points. For example gitiles does it to check if a commit
is visible to a user based on its permissions.
Offer this functionality in JGit.
Split the interface as the next commit will introduce an implementation
using bitmap indices.
Change-Id: I0933b305c8d734f7a64502910ff4d9ef4fc92ae1
Signed-off-by: Ivan Frade <ifrade@google.com>
Use integer depth in PackWriter's DepthAwareVisitationPolicy
- ObjectWalk.getTreeDepth() returns int hence there is no need to use
long depths in the lowestDepthVisited map.
- Also fix boxing warnings introduced in 0a15cb3a.
Change-Id: I6d73b6f41d5d20975d02f376c8588e411eaff0ec
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
ConfigConstants: Fix quoting of section names in javadocs
Replace:
in the "core section"
in the "diff section"
in the "merge section"
with:
in the "core" section
in the "diff" section
in the "merge" section
Change-Id: Ided7bf73e9c8aae4fc4e43d5d5b9f6d7e3066f0a
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Revert 4678f4b and provide another solution for bug 467631
Making gitlinks and folders match in a tree walk was the wrong
approach to fix bug 467631. The problem is that in such a conflict
the tree walk may then not descend into the folder.
Revert the changes to Paths.java and PathsTest.java from commit
4678f4b. Instead test for the problem case from bug 467631 explicitly
in IndexDiff. Add Daniel's test case from bug 545162, and add yet
another test case for DiffEntry.scan() that covers the problem
originally reported in bug 545162.
Bug: 545162
Change-Id: Ie2214c5d5ee32ac6596b621f0f1c7b86d38fa9b7
Also-by: Daniel Veihelmann <daniel.veihelmann@gmail.com>
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
If a tree is visited during pack and filtered out with tree:<depth>, we
may need to include it if it is visited again at a lower depth.
Until now we revisit it no matter what the depth is. Now, avoid
visiting it if it has been visited at a lower or equal depth.
Change-Id: I68cc1d08f1999a8336684a05fe16e7ae51898866
Signed-off-by: Matthew DeVore <matvore@gmail.com>
tree:<depth> should not traverse overly-deep trees
If we are traversing a tree which is too deep, then there is no need to
traverse the children. Skipping children is much faster than traversing
the possibly thousands of objects which are directly or indirectly
referenced by the tree.
Change-Id: I6d68cc1d35da48e3288b9cc80356a281ab36863d
Signed-off-by: Matthew DeVore <matvore@gmail.com>
This is used when fetching, and in particular to populate a partial
clone or a virtual file system cache as the user navigates. With this,
a client can pre-fetch a few directories deeper than only the current
directory.
depth:0 will omit all trees, and is useful if you only want to fetch
the commits of a repository, or fetch just a single tree or blob object.
depth:1 will fetch only the root tree of all commits fetched. depth:2
will fetch the root tree and all blobs and tree objects directly
referenced from it. depth:3 gets one more level, and so on. depth:#
will not filter a blob or tree that is explicitly marked wanted.
Bitmaps are disabled when this filter is used.
This implementation is quite slow because it iterates over all omitted
objects rather than skipping them. This will be addressed in follow-up
commits.
Change-Id: Ic312fee22d60e32cfcad59da56980e90ae2cae6a
Signed-off-by: Matthew DeVore <matvore@gmail.com>
This reverts commit 39b0b51b12. Before
that change, SubmoduleWalk.forPath transferred ownership to the caller
on success. Afterward, it returns a closed SubmoduleWalk to the caller,
which does not appear to be intentional.
Change-Id: I9381daac5153706e24fd9117700089848b58c54e
Replace simple uses of Iterator with a corresponding for-loop.
Also add missing braces on loops as necessary.
Change-Id: I708d82acdf194787e3353699c07244c5ac3de189
Signed-off-by: Carsten Hammer <carsten.hammer@t-online.de>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
DepthGenerator marks commits reinteresting for the ones that are
reachable from unshallow commits as it walks over the revisions. Those
unshallow commits won't necessarily be processed first. Because of this,
even if a commit is reachable from unshallow commits, if it's processed
before the uninteresting commits, it will not be processed as
reinteresting and processed as uninteresting. This causes unshallow
git-fetch to be failed.
This changes DepthGenerator to process unshallow commits first
independent to their depth. This makes uninteresting flag carry work
properly.
Change-Id: I94378271cf85fbe6302cefc19a167d8cf68e1a69
Signed-off-by: Masaya Suzuki <masayasuzuki@google.com>
Keep track of the original cause for a packfile invalidation.
It is needed for the sysadmin to understand if there is a real
underlying filesystem problem and repository corruption or if it is
simply a consequence of a concurrency of Git operations (e.g. repack
or GC).
Change-Id: I06ddda9ec847844ec31616ab6d17f153a5a34e33
Signed-off-by: Luca Milanesio <luca.milanesio@gmail.com>
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Since Java 7 the diamond operator can be used instead of explicit
type parameters.
Change-Id: I2dee5fce7afebb1d9088eeaec4484ee58b4fa492
Signed-off-by: Carsten Hammer <carsten.hammer@t-online.de>
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Use of String.equals("") can be replaced with with String.length() == 0
(for JDK5 and lower) or String.isEmpty() (for JDK6 and higher)
Change-Id: Id1462d22c5d249485d87993263a9239809e73c55
Signed-off-by: Carsten Hammer <carsten.hammer@t-online.de>
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Fix pack files scan when filesnapshot isn't modified
Do not reload packfiles when their associated filesnapshot is not
modified on disk compared to the one currently stored in memory.
Fix the regression introduced by fef78212 which, in conjunction with
core.trustfolderstats = false, caused any lookup of objects inside
the packlist to loop forever when the object was not found in the pack
list.
Bug: 546190
Change-Id: I38d752ebe47cefc3299740aeba319a2641f19391
Signed-off-by: Luca Milanesio <luca.milanesio@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Matthias Sohn
Thomas Wolf
Jonathan Tan
Ivan Frade
Carsten Hammer
David Pursehouse
Matthew DeVore
Jonathan Nieder
Masaya Suzuki
Luca Milanesio