Adds functionality to read the git commit.template property. The
template content is read either via a default encoding or, if present,
via encoding specified by i18n.commitEncoding property.

Bug: 446355

Change-Id: I0c45db98e324ddff26a7e0262835f259d6528a86
Signed-off-by: Julian Ruppel <julian.ruppel@sap.com>

The search for reuse phase for *all* the objects scans *all*
the packfiles, looking for the best candidate to serve back to the
client.

This can lead to an expensive operation when the number of
packfiles and objects is high.

Add parameter "pack.searchForReuseTimeout" to limit the time spent
on this search.

Change-Id: I54f5cddb6796fdc93ad9585c2ab4b44854fa6c48

Rather than getting all ref names and prefixes and saving them
in memory to perform the check for conflicting names, rely on
RefDirectory.isNameConflicting as it is no longer an expensive
call after it was optimized in Ie994fc.

The old optimization to save ref names and prefixes in memory
was targeted towards making clones faster. With this change,
the clone performance is unaffected when tests were done with
repos containing many(~500k) refs.

Here are few recorded elapsed times for creating 10 branches
using BatchRefUpdate on NFS based repositories with varying
loose refs count. As seen here, this change helps improve the
BatchRefUpdate performance from O(n^2) to O(1).

loose_refs_count  with_change  without_change
50                241 ms        310 ms
300               263 ms        1502 ms
1k                181 ms        4241 ms
2k                204 ms        6440 ms
9k                158 ms        25930 ms
20k               154 ms        60443 ms
50k               171 ms        135199 ms
110k              157 ms        329450 ms
160k              209 ms        396328 ms

This update improves the Gerrit notedb migration performance
as it uses BatchRefUpdate to write change meta refs similar to
the test performed above.

Change-Id: I853ac6c7feb4b39c3156c01876b38cbd182accfe
Signed-off-by: Kaushik Lingarkar <quic_kaushikl@quicinc.com>

Add a constant in ConfigConstants, and a ConflictStyle enum in
MergeCommand.

Change-Id: Idf8e036b6b6953bec06d6923a39e5ff30c2da562
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

We introduced the option --initial-branch=<branch-name> to allow
initializing a new repository with a different initial branch.

To allow users to override the initial branch name more permanently
(i.e. without having to specify the name manually for each 'git init'),
introduce the 'init.defaultBranch' option.

This option was added to git in 2.28.0.

See https://git-scm.com/docs/git-config#Documentation/git-config.txt-initdefaultBranch

Bug: 564794
Change-Id: I679b14057a54cd3d19e44460c4a5bd3a368ec848
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Add option --initial-branch/-b to InitCommand and the CLI init command.
This is the first step to implement support for the new option
init.defaultBranch. Both were added to git in release 2.28.

See https://git-scm.com/docs/git-init#Documentation/git-init.txt--bltbranch-namegt

Bug: 564794
Change-Id: Ia383b3f90b5549db80f99b2310450a7faf6bce4c
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Add a GpgSignatureVerifier interface, plus a factory to create
instances thereof that is provided via the ServiceLoader mechanism.

Implement the new interface for BouncyCastle. A verifier maintains
an internal LRU cache of previously found public keys to speed up
verifying multiple objects (tag or commits). Mergetags are not handled.

Provide a new VerifySignatureCommand in org.eclipse.jgit.api together
with a factory method Git.verifySignature(). The command can verify
signatures on tags or commits, and can be limited to accept only tags
or commits. Provide a new public WrongObjectTypeException thrown when
the command is limited to either tags or commits and a name resolves
to some other object kind.

In jgit.pgm, implement "git tag -v", "git log --show-signature", and
"git show --show-signature". The output is similar to command-line
gpg invoked via git, but not identical. In particular, lines are not
prefixed by "gpg:" but by "bc:".

Trust levels for public keys are read from the keys' trust packets,
not from GPG's internal trust database. A trust packet may or may
not be set. Command-line GPG produces more warning lines depending
on the trust level, warning about keys with a trust level below
"full".

There are no unit tests because JGit still doesn't have any setup to
do signing unit tests; this would require at least a faked .gpg
directory with pre-created key rings and keys, and a way to make the
BouncyCastle classes use that directory instead of the default. See
bug 547538 and also bug 544847.

Tested manually with a small test repository containing signed and
unsigned commits and tags, with signatures made with different keys
and made by command-line git using GPG 2.2.25 and by JGit using
BouncyCastle 1.65.

Bug: 547751
Change-Id: If7e34aeed6ca6636a92bf774d893d98f6d459181
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Add it to the GpgConfig. Change GpgConfig to load the values once only.
Add a parameter to the GpgObjectSigner interface's operations to pass
in a GpgConfig. Update CommitCommand and TagCommand to pass the value
to the signer. Let the signer decide whether it can actually produce
the wanted signature type (openpgp or x509).

No behavior change. But this makes it possible to implement different
signers that might support x509 signatures, or use gpg.program and
shell out to an external GPG executable for signing.

Change-Id: I427f83eb1ece81c310e1cddd85315f6f88cc99ea
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Reachability checkers are retrieved from RevWalk and ObjectWalk objects:
* RevWalk.createReachabilityChecker()
* ObjectWalk.createObjectReachabilityChecker()

Since RevWalks and ObjectWalks are themselves directly instantiated
in hundreds of places (e.g. UploadPack...) overriding them in a
consistent way requires overloading 100s of methods, which isn't
feasible. Moving reachability checker generation to a more central
place solves that problem.

The ObjectReader object seems a good place from which to get
reachability checkers, because reachability checkers return
information about relationships between objects. ObjectDatabases
delegate many operations to ObjectReaders, and reachability bitmaps
are attached to ObjectReaders.

The Bitmapped and Pedestrian reachability checker objects were
package private in the org.eclipse.jgit.revwalk package. This change
makes them public and moves them to the
org.eclipse.jgit.internal.revwalk package. Corresponding tests are
also moved.

Motivation:
1) Reachability checking algorithms need to scale. One of the
   internal Android repositories has ~2.4 million refs/changes/*
   references, causing bad long tail performance in reachability
   checks.
2) Reachability check performance is impacted by repository
   topography: number of refs, number of objects, amounts of
   related vs. unrelated history.
3) Reachability check performance is also affected by per-branch
   access (Gerrit branch permissions) since different users can
   see different branches.
4) Reachability check performance isn't affected by any state in a
   RevWalk or ObjectWalk.

I don't yet know if a single algorithm will work for all cases in #2
and #3. We may need to evolve the ReachabilityChecker interfaces
over time to solve the Gerrit branch permissions case, or use
Gerrit-specific identity information to solve that in an efficient
way.

This change takes the existing public API and moves it to the
ObjectReader/whole repository level, which is where we can do
consistent customizations for #2 and #3. We intend to upstream the
best of whatever works, but anticipate the need for multiple rounds
of experimentation.

Change-Id: I9185feff43551fb387957c436112d5250486833d
Signed-off-by: Terry Parker <tparker@google.com>

We sometimes want to get all the refs except specific prefixes,
similarly to getRefsByPrefix that gets all the refs of a specific
prefix.

We now create a new method that gets all refs matching a prefix except a
set of specific prefixes.

One use-case is for Gerrit to be able to get all the refs except
refs/changes; in Gerrit we often have lots of refs/changes, but very
little other refs. Currently, to get all the refs except refs/changes we
need to get all the refs and then filter the refs/changes, which is very
inefficient. With this method, we can simply skip the unneeded prefix so
that we don't have to go over all the elements.

RefDirectory still uses the inefficient implementation, since there
isn't a simple way to use Refcursor to achieve the efficient
implementation (as done in ReftableDatabase).

Signed-off-by: Gal Paikin <paiking@google.com>
Change-Id: I8c5db581acdeb6698e3d3a2abde8da32f70c854c

This fixes errorprone error [SynchronizeOnNonFinalField]: Synchronizing
on non-final fields is not safe: if the field is ever updated, different
threads may end up locking on different objects.

Change-Id: I42fe5bde825151693e2da2d5b6cd6e1d34038dbc

On Android, the co-variant override of ConcurrentHashMap.keySet()
introduced in Java 8 was undone. [1] If compiled Java code calls that
co-variant override directly, one gets a NoSuchMethodError exception
at run-time on Android.

Making the code call that method via Map.keySet() side-steps this
problem.

This is similar to bug 496262, where the same problem cropped up when
compiling with Java 8 against a Java 7 target, but here we cannot use
bootclasspath. We build against Java 8, not against the Android version
of it.

Recent Android versions should have some bytecode "magic" that adds the
co-variant override in bytecode (see the commit referenced in [1]), but
on older Android version this problem may still occur. (Or perhaps the
"magic" is ineffective...) There are two pull requests on Github for
this problem, both from 2020, [2][3] while the Android commit [1] is
from March 2018. Apparently people still occasionally run into this
problem in the wild.

[1] 0e8b937ded/ojluni/src/main/java/java/util/concurrent/ConcurrentHashMap.java (1244)
[2] https://github.com/eclipse/jgit/pull/104
[3] https://github.com/eclipse/jgit/pull/100

Change-Id: I7c07e0cc59871cb7fe60795e22867827fa9c2458
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Use a dedicated Lock object to lock the scheduler in
RepositoryCache#configureEviction to fix spotbugs warning
JLM_JSR166_UTILCONCURRENT_MONITORENTER.

Change-Id: I003dcf0ed1a0a3f4eea5d8a2f51a07473d28a928
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

This was experimental code and never used in production.

Change-Id: Ia3da7f2b82d9e365cec2ccf9397cbc47439cd150
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Add the two config constants from C git that can switch on signing
of annotated tags. Add them to the GpgConfig, and implement actually
signing a tag in TagCommand.

The interactions between command line options for "git tag" and config
options is a bit murky in C git. There are two config settings for it:

* tag.gpgSign is the main option, if set to true, it kicks in if
  neither -s nor -u are given on the command line.
* tag.forceSignAnnotated signs only tags created via "git tag -m",
  but only if command-line option "-a" is not present. It applies
  even if tag.gpgSign is set explicitly to false.

Giving -s or -u on the command line also forces an annotated tag
since lightweight tags cannot be signed.

Bug: 386908
Change-Id: Ic8a1a44b5f12f47d5cdf3aae2456c1f6ca9ef057
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Factor out a common ObjectBuilder as super class of CommitBuilder
and TagBuilder, and make the GpgSigner work on ObjectBuilder.

In order not to break API, add the new method for signing an
ObjectBuilder in a new interface GpgObjectSigner.

The signature for a tag is just tacked onto the end of the tag
message. The message of a signed tag must end in LF.

Bug: 386908
Change-Id: I5e021e3c927f4051825cd7355b129113b949455e
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

This would allow other JGit users to access and reuse the constants.

Change-Id: I1608802f45586af5f8582afa592e26679e9cebe3
Signed-off-by: David Ostrovsky <david@ostrovsky.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

This enables EGit to override with a lenient variant that logs the
problem and continues with the default value. EGit needs this because
otherwise a corrupt core.excludesFile entry can render the whole UI
unusable (until the git config is fixed) because any use of the
WorkingTreeIterator will throw an InvalidPathException.

This is not a problem on OS X, where all characters are allowed in
file names. But on Windows some characters are forbidden... see bug
567296. The message of the InvalidPathException is not helpful since
it doesn't point to the origin of the problem. EGit can log a much
better message indicating the offending config file and entry in the
Eclipse error log, where the user can see it.

Bug: 567309
Change-Id: I4e57afa715ff3aaa52cd04b5733f69e53af5b1e0
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Index format version 4 was introduced in C git in 2012. It's about
time that JGit can deal with it.

Version 4 added prefix path compression. Instead of writing the full
path for each index entry to disk, only the difference to the previous
entry's path is written: a variable-encoded int telling how many bytes
to remove from the previous entry's path to get the common prefix,
followed by the new suffix.

Also, cache entries in a version 4 index are not padded anymore.

Internally, version 3 and version 4 index entries are identical; it's
only the stored format that changes.

Implement this path compression, and make sure we write an index file
that we read previously in the same format. (Only changing from version
2 to version 3 if there are extended flags.)

Add support for the "feature.manyFiles" and the "index.version" git
configs, and honor them when writing a new index file.

Add tests, including a compatibility test that verifies that JGit can
read a version 4 index generated by C git and write an identical
version 4 index.

Bug: 565774
Change-Id: Id83241cf009e50f950eb42f8d56b834fb47da1ed
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Change-Id: I7c44e3603df2dd368cb7c0ba0072413b887b6903
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Make sure we don't produce a spurious empty line at the end.

Bug: 564428
Change-Id: Ib991d93fbd052baca65d32a7842f07f9ddeb8130
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Change-Id: I1635b79c8051699a3a5e78a4cef8d2014be4e92c
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Running recent error prone version complaining on that code:

RefDatabase.java:444: error: [InvalidInlineTag] Tag name `linkObjectId`
is unknown.
	 * Includes peeled {@linkObjectId}s. This is the inverse lookup of
	                   ^
    (see https://errorprone.info/bugpattern/InvalidInlineTag)

Bug: 562756
Change-Id: If91da51d5138fb753c0550eeeb9e3883a394123d
Signed-off-by: David Ostrovsky <david@ostrovsky.org>

Motivation: BouncyCastle serves as 'default' implementation of
the GPG Signer. If a client application does not use it there is no need
to pull in this dependency, especially since BouncyCastle is a large
library.

Move the classes depending on BouncyCastle to an OSGi fragment extending
the org.eclipse.jgit bundle. They are moved to a distinct internal
package in order to avoid split packages. This doesn't break public API
since these classes were already in an internal package before this
change.

Add a new feature org.eclipse.jgit.gpg.bc to enable installation. With
that users can now decide if they want to install it.

Attempts to sign a commit if org.eclipse.jgit.gpg.bc isn't available
will result in ServiceUnavailableException being thrown.

Bug: 559106
Change-Id: I42fd6c00002e17aa9a7be96ae434b538ea86ccf8
Also-by: Michael Dardis <git@md-5.net>
Signed-off-by: Michael Dardis <git@md-5.net>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Signed-off-by: David Ostrovsky <david@ostrovsky.org>

Update dependency to Bouncy Castle to 1.65.

Add the IssuerFingerprint as a hashed sub-packet in the signature. If
added unhashed, GPG ignores it.

Bug: 553206
Change-Id: I6807e8e2385e6ec5790f388e4753a44aa9474ebb
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Make retrieveCompressed() a method of Bitmap interface to avoid type
casting and later reuse in improving the memory footprint of GC's bitmap
generation phase.

Change-Id: I098d85105cf17af845d43b8c71b4ca48b02fd7da
Signed-off-by: Yunjie Li <yunjieli@google.com>

Bug: 560903
Change-Id: I15d45330398cc573940265d16a2db29ddce085aa
Signed-off-by: Konrad Windszus <konrad_w@gmx.de>

Change-Id: Ifb8227cb62370029d6774f2a22b15d6478c713ca
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

The change Ic0b974fa (c217d33, "Documentation/technical/reftable:
improve repo layout") defines a new repository layout, which was
agreed with the git-core mailing list.

It addresses the following problems:

* old git clients will not recognize reftable-based repositories, and
  look at encompassing directories.

* Poorly written tools might write directly into
  .git/refs/heads/BRANCH.

Since we consider JGit reftable as experimental (git-core doesn't
support it yet), we have no backward compatibility. If you created a
repository with reftable between mid-Nov 2019 and now, you can do the
following to convert:

  mv .git/refs .git/reftable/tables.list
  git config core.repositoryformatversion 1
  git config extensions.refStorage reftable

Change-Id: I80df35b9d22a8ab893dcbe9fbd051d924788d6a5
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

The Java Language Specification recommends listing modifiers in
the following order:

1. Annotations
2. public
3. protected
4. private
5. abstract
6. static
7. final
8. transient
9. volatile
10. synchronized
11. native
12. strictfp

Not following this convention has no technical impact, but will reduce
the code's readability because most developers are used to the standard
order.

This was detected using SonarLint.

Change-Id: I9cddecb4f4234dae1021b677e915be23d349a380
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

Change-Id: I613489a937dd53780b0abfd6b1bd0ed964a5ddd8
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

Nested enum types are implicitly static.

Change-Id: Id3d7886087494fb67bc0d080b4a3491fb4baac19
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

Enable UnusedException at ERROR level which causes the build to fail
in many places with:

  [UnusedException] This catch block catches an symbol and re-throws
  another, but swallows the caught symbol rather than setting it as a
  cause. This can make debugging harder.

Fix it by setting the caught exception as cause on the subsequently
thrown exception.

Note: The grammatically incorrect error message is copy-pasted as-is
from the version of ErrorProne currently used in Bazel; it has been
fixed by [1] in the latest version.

[1] https://github.com/google/error-prone/commit/d57a39c

Change-Id: I11ed38243091fc12f64f1b2db404ba3f1d2e98b5
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Java GC evicts all SoftReferences when the used heap size comes close to
the maximum heap size. This means peaks in heap memory consumption can
flush the complete WindowCache which was observed to have negative
impact on performance of upload-pack in Gerrit.

Hence add a boolean option core.packedGitUseStrongRefs to allow using
strong references to reference packfile pages cached in the WindowCache.

If this option is set to true Java gc can no longer flush the
WindowCache to free memory if the used heap comes close to the maximum
heap size. On the other hand this provides more predictable performance.

Bug: 553573
Change-Id: I9de406293087ab0fa61130c8e0829775762ece8d
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Change-Id: Icc5265f87ae58aa1e667ed1827075c4a30f75c32
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

This is the format given by the Eclipse legal doc generator [1].

[1] https://www.eclipse.org/projects/tools/documentation.php?id=technology.jgit

Bug: 548298
Change-Id: I8d8cabc998ba1b083e3f0906a8d558d391ffb6c4
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

When converting to reftable format the option extensions.refStorage must
be set to "reftable" [1]. When converting back to refdir format this
config option needs to be removed.

Introduce constants for refStorage config options, also for the
"reftree" format.

[1] https://git.eclipse.org/r/plugins/gitiles/jgit/jgit/+/master/Documentation/technical/reftable.md#Version-1

Change-Id: I190222fa5edc1ad7309daa9be17ca934ff7971e3
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

and switch over strings where possible. Sometimes if statements are
chained and form a series of comparisons against constants. Using switch
statements improves readability.

Bug: 545856
Change-Id: Iacb78956ee5c20db4d793e6b668508ec67466606
Signed-off-by: Carsten Hammer <carsten.hammer@t-online.de>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Add the following statistics
- cache hit count and hit ratio
- cache miss count and miss ratio
- count of successful and failed loads
- rate of failed loads
- load, eviction and request count
- average and total load time

Use LongAdder instead of AtomicLong to implement counters in order to
improve scalability.

Optionally expose these metrics via JMX, they are registered with the
platform MBean server if the config option jmx.WindowCacheStats = true
in the user or system level git config.

Bug: 553573
Change-Id: Ia2d5246ef69b9c2bd594a23934424bc5800774aa
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

The reftable format supports fast inverse (SHA1 => ref) queries.

If the ref database does not support fast inverse queries, it may be
advantageous to build a complete SHA1 to ref map in advance for
multiple uses. To let applications decide, this function indicates
whether the inverse map is available.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Change-Id: Idaf7e01075906972ec21332cade285289619c2b3

Reftable-enabled repositories don't have a file called HEAD. Check for
reftable/ instead.

This fixes repository creation on reftable in Gerrit.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Change-Id: I778c2be01d96aaf135affae4b457b5fe5b483bee

Reftable is a binary, block-based storage format for the ref-database.
It provides several advantages over the traditional packed + loose
storage format:

 * O(1) write performance, even for deletions and transactions.

 * atomic updates to the ref database.

 * O(log N) lookup and prefix scans

 * free from restrictions imposed by the file system: it is
   case-sensitive even on case-insensitive file systems, and has
   no inherent limitations for directory/file conflicts

 * prefix compression reduces space usage for repetitive ref names,
   such as gerrit's refs/changes/xx/xxxxx format.

FileReftableDatabase is based on FileReftableStack, which does
compactions inline. This is simple, and has good median performance,
but every so often it will rewrite the entire ref database.

For testing, a FileReftableTest (mirroring RefUpdateTest) is added to
check for Reftable specific behavior. This must be done separately, as
reflogs have different semantics.

Add a reftable flavor of BatchRefUpdateTest.

Add a FileReftableStackTest to exercise compaction.

Add FileRepository#convertToReftable so existing testdata can be
reused.

CQ: 21007
Change-Id: I1837f268e91c6b446cb0155061727dbaccb714b8
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

core.quotePath = false means that "bytes higher than 0x80 are not
considered "unusal" anymore"[1], i.e., they are not escaped. In
essence this preserves non-ASCII characters in path names in output.

Note that control characters and other special characters in the
ASCII range will still be escaped.

Add a new QuotedString.GIT_PATH_MINIMAL singleton implementing this.
Change the normal GIT_PATH algorithm to use bytes instead of characters
so it can be re-used. Provide a setter in DiffFormatter for the quoting
style so that an application can override the default, which is the
setting from the git config (and by default "true"). Use the new
QuotedString.GIT_PATH_MINIMAL when core.quotePath == false.

[1] https://git-scm.com/docs/git-config#Documentation/git-config.txt-corequotePath

Bug: 552467
Change-Id: Ifcb233e7d10676333bf42011e32d01a4e1138059
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Some applications using JGit use their own repository caching. In
such applications, it may be needlessly inefficient to create new
submodule repositories from a SubmoduleWalk or in an IndexDiff. It
can be much more efficient to use an already cached repository
instance.

Provide a way to configure a SubmoduleWalk with a factory to create
BaseRepositoryBuilders to use to create repositories, and use it in
IndexDiff. Provide new IndexDiff.diff() operations that take such an
additional factory as parameter.

An application that caches Repository instances (for instance EGit)
can use a factory that provides builders that don't create a new
Repository instance but that return the already cached instance, if
one is available. Note that in such a case, the application may need
to be prepared to deal with IndexDiff.diff() also _closing_ the
obtained repository; if the application expects its cached Repository
instances to remain open while being cached, it'll have to use
Repository.incrementOpen() to prevent that the repository instance
gets closed.

Bug: 550878
Change-Id: Icc1b34dfc4cebd8ed4739dd09d37744d41adf711
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

IndexDiff would apply ignore mode ALL from .gitmodules to all remaining
submodules, and would ignore other settings from .gitignore and always
apply the setting defined on the IndexDiff instead. Correct that.

In canonical git the ignore setting from .gitmodules can also be
overridden by .git/config.[1] Implement that override in SubmoduleWalk.

[1] https://git-scm.com/docs/gitmodules#Documentation/gitmodules.txt-submoduleltnamegtignore

Bug: 521613
Change-Id: I9199fd447e41c7838924856dce40678370b66395
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

This avoids polluting hand-crafted user level config with
auto-configured options which might disturb in environments where
the user level config is replicated between different machines.

Add a jgit config as parent of the system level config. Persist
measured timestamp resolutions always in this jgit config and read it
via the user global config. This has the effect that auto-configured
timestamp resolution will be used by default and can be overridden in
either the system level or user level config.

Store the jgit config under the XDG_CONFIG_HOME directory following the
XDG base directory specification [1] in order to ensure that we have
write permissions to persist the file. This has the effect that each OS
user will use its jgit config since they typically use different
XDG_CONFIG_HOME directories.

If the environment variable XDG_CONFIG_HOME is defined the jgit config
file is located at $XDG_CONFIG_HOME/jgit/config otherwise the default is
~/.config/jgit/config.

If you want to avoid redundant measurement for different OS users
manually copy the values measured and auto-configured for one OS user to
the system level git config.

[1] https://wiki.archlinux.org/index.php/XDG_Base_Directory

Bug: 551850
Change-Id: I0022bd40ae62f82e5b964c2ea25822eb55d94687
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Change-Id: Ia77f442e47c5670c2d6d279ba862044016aabd86
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Instead of just looking for a substring match of user.signingKey
in a key's user ID implement the GPG matching formats[1] for:

'=' Full exact match
'<' Full exact match of the e-mail address
'@' Substring match within the e-mail address only
'*' General case-insensitive substring match (default)

When user.signingKey is not set, the committer's e-mail address is
used by default. In that case, use '<', i.e., require an exact match
on the OpenPGP e-mail address.

Also handle the optional "0x" prefix for (partial) key fingerprints.

[1] https://www.gnupg.org/documentation/manuals/gnupg/Specify-a-User-ID.html

Bug: 550335
Change-Id: I6ce482a099ff1a0dc9de45435cd4d3ec5b504f12
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Currently when a GPG key is looked up using a user identity the first
key from the keyring that has this user identity is returned.
The code was changed to instead return the first signing [S] key in this
keyring and only return the master key if no such signing key was found.
If the master key also does not have the signing flag set null is
returned instead.

Bug: 552288
Change-Id: I194862991d13c2c7ff34a60a54a227167f88f53b
Signed-off-by: Roan Hofland <roan.hofland@hotmail.com>

Currently when a subkey is configured for signing via the git
user.signingkey configuration option the first key from the keyring for
this subkey would be returned for use (master key). The code has been
changed to return the requested key from the keyring instead.

Bug: 552288
Change-Id: I1c1cdf64c1667316a274ff9d829fc2b563797f2a
Signed-off-by: Roan Hofland <roan.hofland@hotmail.com>