This is similar to change Idbc2c29bd that skipped detecting content
renames for large files. With this change, we added a new option in
RenameDetector called "skipContentRenamesForBinaryFiles", that when set,
causes binary files with any slight modification to be identified as
added/deleted. The default for this boolean is false, so preserving
current behaviour.

Change-Id: I4770b1f69c60b1037025ddd0940ba86df6047299

Don't create the stream eagerly in lock(); that may cause JGit to
exceed OS or JVM limits on open file descriptors if many locks need
to be created, for instance when creating many refs. Instead create
the output stream only when one really needs to write something.

Bug: 573328
Change-Id: If9441ed40494d46f594a896d34a5c4f56f91ebf4
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Don't create the stream eagerly in lock(); that may cause JGit to
exceed OS or JVM limits on open file descriptors if many locks need
to be created, for instance when creating many refs. Instead create
the output stream only when one really needs to write something.

Bug: 573328
Change-Id: If9441ed40494d46f594a896d34a5c4f56f91ebf4
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Git has different conflict resolution strategies:

* There is a tree merge strategy "ours" which just ignores any changes
  from theirs ("-s ours"). JGit also has the mirror strategy "theirs"
  ignoring any changes from "ours". (This doesn't exist in C git.)
  Adapt StashApplyCommand and CherrypickCommand to be able to use those
  tree merge strategies.
* For the resolve/recursive tree merge strategies, there are content
  conflict resolution strategies "ours" and "theirs", which resolve
  any conflict hunks by taking the "ours" or "theirs" hunk. In C git
  those correspond to "-Xours" or -Xtheirs". Implement that in
  MergeAlgorithm, and add API to set and pass through such a strategy
  for resolving content conflicts.
* The "ours/theirs" content conflict resolution strategies also apply
  for binary files. Handle these cases in ResolveMerger.

Note that the content conflict resolution strategies ("-X ours/theirs")
do _not_ apply to modify/delete or delete/modify conflicts. Such
conflicts are always reported as conflicts by C git. They do apply,
however, if one side completely clears a file's content.

Bug: 501111
Change-Id: I2c9c170c61c440a2ab9c387991e7a0c3ab960e07
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Change-Id: I34718829435daf8ded4ce596c824dd3cfbafbaf6
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Similar to https://git.eclipse.org/r/c/jgit/jgit/+/175166, ignore
path that have conflicts on attributes, so that the virtual base could
be used by RecursiveMerger.

Change-Id: I99c95445a305558d55bbb9c9e97446caaf61c154
Signed-off-by: Marija Savtchouk <mariasavtchouk@google.com>

In cases where we need to determine if a given commit is merged
into many refs, using isMergedInto(base, tip) for each ref would
cause multiple unwanted walks.

getMergedInto() marks the unreachable commits as uninteresting
which would then avoid walking that same path again.

Using the same api, also introduce isMergedIntoAny() and
isMergedIntoAll()

Change-Id: I65de9873dce67af9c415d1d236bf52d31b67e8fe
Signed-off-by: Adithya Chakilam <quic_achakila@quicinc.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

There are two code paths for detecting renames: one on tree diffs
(using DiffFormatter#scan) and the other on single file diffs (using
DiffFormatter#format). The latter skips binary and large files
for rename detection - check [1], but the former doesn't.

This change skips content rename detection for the tree diffs case for
large files. This is essential to avoid expensive computations while
reading the file, especially for callers who don't want to pay that
cost. Content renames are those which involve files with slightly
modified content. Exact renames will still be identified.

The default threshold for file sizes is reused from
PackConfig.DEFAULT_BIG_FILE_THRESHOLD: 50 MB.

[1] 232876421d/org.eclipse.jgit/src/org/eclipse/jgit/diff/RawText.java (386)

Change-Id: Idbc2c29bd381c6e387185204638f76fda47df41e
Signed-off-by: Youssef Elghareeb <ghareeb@google.com>

Add new constructors to PackFile to improve a common use case where
callers know the directory, id, and extension, but previously needed to
construct a valid file name (with prefix, '.', etc) to create a
PackFile. Most callers can use the variant that has id as an ObjectId,
but provide an id as String variant too.

Change-Id: I39e4466abe8c9509f5916d5bfe675066570b8585
Signed-off-by: Nasser Grainawi <quic_nasserg@quicinc.com>

Provide a recovery path for objects being referenced during the pack
pruning race. Due to the pack pruning race, it is possible for objects
to become referenced after a pack has been deemed safe to prune, but
before it actually gets pruned. If this happened previously, the newly
referenced objects would be missing and potentially result in a
corrupted ref.

Add the ability to recover from this situation when an object is missing
but happens to still be available in a pack in the "preserved"
directory. This is likely only useful when used in conjunction with the
--preserve-old-packs GC option, which prunes packs by hard-linking to
the preserved directory. If an object is missing and found in a pack in
the preserved directory, immediately recover that pack and its
associated files (idx, bitmaps...) by moving them back to the original
pack directory, and then retry the operation that would have failed due
to the missing object. This retry can now succeed and the repository
may avoid corruption. This approach should drastically reduce the
chance of a corrupt repository during pack pruning at very little extra
cost. This extra cost should only be incurred when objects are missing
and a failure would normally occur.

Change-Id: I2a704e3276b88cc892159d9bfe2455c6eec64252
Signed-off-by: Martin Fick <quic_mfick@quicinc.com>
Signed-off-by: Nasser Grainawi <quic_nasserg@quicinc.com>

The only extension that was ever consulted from the bitmap was the
bitmap index. We can simplify the Pack code as well as the code of
all the callers if we focus on just that usage.

Change-Id: I799ddfdee93142af67ce5081d14a430d36aa4c15
Signed-off-by: Nasser Grainawi <quic_nasserg@quicinc.com>

The PackFile class is intended to be a central place to do all
common pack filename manipulation and parsing to help reduce repeated
code and bugs. Use the PackFile class in the Pack class and in many
tests to ensure it works well in a variety of situations. Later changes
will expand use of PackFiles to even more areas.

Change-Id: I921b30f865759162bae46ddd2c6d669de06add4a
Signed-off-by: Nasser Grainawi <quic_nasserg@quicinc.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

A cookie file stores the expiration in seconds since the Linux Epoch,
not in milliseconds. Correct reading and writing cookie files; with
a backwards-compatibility hack to read files that contain a millisecond
timestamp.

Add a test, and fix tests not to rely on the actual current time so
that they will also run successfully after 2030-01-01 noon.

Bug: 571574
Change-Id: If3ba68391e574520701cdee119544eedc42a1ff2
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>

Change-Id: Idf4887a99e87c375ec32e2fd289cfce82d78cbce
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Pack better represents the purpose of the object and paves the way to
add a PackFile object that extends File.

Change-Id: I39b4f697902d395e9b6df5e8ce53078ce72fcea3
Signed-off-by: Nasser Grainawi <quic_nasserg@quicinc.com>

If RecursiveMerger finds multiple base commits, it tries to compute
the virtual ancestor to use as a base for the three way merge.
Currently, the content conflicts between ancestors are ignored (file
staged with the conflict markers). If the path is a file in one ancestor
and a dir in the other, it results in NoMergeBaseException
(CONFLICTS_DURING_MERGE_BASE_CALCULATION).

Allow these conflicts by ignoring this unmerged path in the virtual
base. The merger will compute diff in the children instead and it
can be further fixed manually if needed.

Change-Id: Id59648ae1d6bdf300b26fff513c3204317b755ab
Signed-off-by: Marija Savtchouk <mariasavtchouk@google.com>

DateRevQueue is expected to give out the commits that have higher
commit time. But in case of tie(same commit time), it should give
the commit that is inserted first. This is inferred from the
testInsertTie test case written for DateRevQueue. Also that test
case, right now uses just two commits which caused it not to fail
with the current implementation, so added another commit to make
the test more robust.

By fixing the DateRevQueue, we would also match the behaviour of
LogCommand.addRange(c1,c2) with git log c1..c2. A test case for
the same is added to show that current behaviour is not the
expected one.

By fixing addRange(), the order in which commits are applied during
a rebase is altered. Rebase logic should have never depended upon
LogCommand.addRange() since the intended order of addRange() is not
the order a rebase should use. So, modify the RebaseCommand to use
RevWalk directly with TopoNonIntermixSortGenerator.

Add a new LogCommandTest.addRangeWithMerge() test case which creates
commits in the following order:

         A - B - C - M
              \     /
                -D-

Using git 2.30.0, git log B..M outputs:  M C D
LogCommand.addRange(B, M) without this fix outputs: M D C
LogCommand.addRange(B, M) with this fix outputs: M C D

Change-Id: I30cc3ba6c97f0960f64e9e021df96ff276f63db7
Signed-off-by: Adithya Chakilam <achakila@codeaurora.org>

This would run into an endless loop if the offset given was not zero.
Fix the logic to exit the read loop when the buffer is full.

Luckily all existing uses of this method call it only with offset zero.

Change-Id: I0ec2a4fb43efe4a605d06ac2e88cf155d50e2f1e
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>

Different archive formats support a compression level in the range
[0-9]. The value 0 is for lowest compressions and 9 for highest. Highest
levels produce output files of smaller sizes but require more memory to
do the compression.

This change allows passing a "compression-level" option to the git
archive command and implements using it for different file formats.

Change-Id: I5758f691c37ba630dbac24db67bb7da827bbc8e1
Signed-off-by: Youssef Elghareeb <ghareeb@google.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.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 method will be used by the follow-up change. This useful if we want
to go over all the changes after a specific ref.

For example, the new method allows us to create a follow-up that would
go over all the refs until we reach a specific ref (e.g refs/changes/),
and then we use seekPastPrefix(refs/changes/) to read the rest of the refs,
thus basically we return all refs except a specific prefix.

When seeking past a prefix, the previous condition that created the
RefCursor still applies. E.g, if the cursor was created by
seekRefsWithPrefix, we can skip some refs but we will not return refs
that are not starting with this prefix.

Signed-off-by: Gal Paikin <paiking@google.com>
Change-Id: I2c02e89c877fe90da8619cb8a4a9a0c865f238ef

Heap always copied whole blocks, which leads to AIOOBEs. LocalFile
didn't overwrite the method and thus caused NPEs.

Change-Id: Ia37d4a875df9f25d4825e6bc95fed7f0dff42afb
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Signatures on tags are just tacked onto the end of the message.
Getting the message must not return the signature. Compare [1]
and [2] in C git, which both drop a signature at the end of an
object body.

[1] https://github.com/git/git/blob/21bf933/builtin/tag.c#L173
[2] https://github.com/git/git/blob/21bf933/ref-filter.c#L1276

Change-Id: Ic8a1062b8bc77f2d7c138c3fe8a7fd13b1253f38
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Make all transports request protocol V2 when fetching. Depending on
the transport, set the GIT_PROTOCOL environment variable (file and
ssh), pass the Git-Protocol header (http), or set the hidden
"\0version=2\0" (git anon). We'll fall back to V0 if the server
doesn't reply with a version 2 answer.

A user can control which protocol the client requests via the git
config protocol.version; if not set, JGit requests protocol V2 for
fetching. Pushing always uses protocol V0 still.

In the API, there is only a new Transport.openFetch() version that
takes a collection of RefSpecs plus additional patterns to construct
the Ref prefixes for the "ls-refs" command in protocol V2. If none
are given, the server will still advertise all refs, even in protocol
V2.

BasePackConnection.readAdvertisedRefs() handles falling back to
protocol V0. It newly returns true if V0 was used and the advertised
refs were read, and false if V2 is used and an explicit "ls-refs" is
needed. (This can't be done transparently inside readAdvertisedRefs()
because a "stateless RPC" transport like TransportHttp may need to
open a new connection for writing.)

BasePackFetchConnection implements the changes needed for the protocol
V2 "fetch" command (stateless protocol, simplified ACK handling,
delimiters, section headers).

In TransportHttp, change readSmartHeaders() to also recognize the
"version 2" packet line as a valid smart server indication.

Adapt tests, and run all the HTTP tests not only with both HTTP
connection factories (JDK and Apache HttpClient) but also with both
protocol V0 and V2. The SSH tests are much slower and much more
focused on the SSH protocol and SSH key handling. Factor out two
very simple cloning and pulling tests and make those run with
protocol V2.

Bug: 553083
Change-Id: I357c7f5daa7efb2872f1c64ee6f6d54229031ae1
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

If a file exists in head, merge, and the working tree, but not in
the index, and we're doing a force checkout, the checkout must be
an "update", not a "keep".

This is a follow-up on If3a9b9e60064459d187c7db04eb4471a72c6cece.

Bug: 569962
Change-Id: I59a7ac41898ddc1dd90e86b09b621a41fdf45667
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Path#getFileName can return null. Fix the warning by asserting the file
name isn't null.

Change-Id: I7f2fe75b46113d8be1d14e3f18dd77da27df25ed
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

File#listFiles can return null. Use Files#list instead to fix the
problem.

Change-Id: I74e0b49aa6dae370219507c64aa43be4d8aa7b82
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Path#getParent can return null. Fix the warning by implementing a helper
method which asserts the parent is not null.

Change-Id: Ib4f8dff0674b74bc891f15f08bd9755c5ea728dc
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

File#listFiles can return null, assert it is not null to fix the
warning.

Change-Id: I28fc668fee760d39965e6e039003ac9f85fd461b
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>

Some clients may wish to allow NO_CHANGE lightweight tag updates
without setting the force flag. (For instance EGit does so.)
Command-line git does not allow this.

Propagate the RefUpdate result via the RefAlreadyExistsException.
That way a client has the possibility to catch it and check the
failure reason without having to parse the exception message, and
take appropriate action, like ignoring the exception on NO_CHANGE.

Change-Id: I60e7a15a3c309db4106cab87847a19b6d24866f6
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

JGit treated a NO_CHANGE RefUpdate as an error in all cases. But when
updating a lightweight tag, this is a successful result if -f was
specified.

Change-Id: Iddfa6d6a6dc8bf8fed81138a008ebc32d5f960bd
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

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>

Observed the error when trying to force checkout from a branch
that had no changes on it. When the 'keep()' method from 'DirCacheCheckout'
method was called the 'DirCacheEntry e' was null and was passed like
this to the 'checkoutEntry()' method where the 'getObjectId()' is
being called on the 'e' object

Change-Id: If3a9b9e60064459d187c7db04eb4471a72c6cece

Change-Id: Icd6b876e392c55a7322a990ac7f618250b732b4b
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Explicitly test that END and DELIM can be distinguished. If not, the
wire protocol V2 breaks down.

Bug: 568950
Change-Id: I5f3496168244303c68893f1c756831dd27440aeb
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>

Change-Id: Id78f4fd7d11a8908f41160a2ab9f3d81b7f771da
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

A SymbolicRef is added to the advertised refs for any symref in
capabilities whose target is an advertised ref; this may replace an
existing entry, such as HEAD.

When cloning, if any advertised HEAD is symbolic then use the target
rather than looking for an advertised ref with a matching objectId.

Add --symref option to LsRemote command.

Bug: 514052
Change-Id: Idfb48e6f6e8dcfe57a6896883fe6d84d533aa9d0
Signed-off-by: Lee Worrall <worrall.la@gmail.com>

If pack or index files are guarded by a pack lock (.keep file)
deleteOrphans() should not touch the respective files protected by the
lock file. Otherwise it may interfere with PackInserter concurrently
inserting a new pack file and its index.

The problem was caused by the following race.

All mentioned files are located in  "objects/pack/".
File endings relevant in "pack" dir:
  .pack
  .keep
  .idx
  .bitmap

When ReceivePack receives a pack file it executes the following steps:

ReceivePack.service():
  receivePackAndCheckConnectivity():
    receivePack():
      receive the pack
      parse the pack, returns packLock (.keep file)
      PackInserter.flush():
        write tmpPck file:  "insert_<random>.pack"
        write tmpIdx file:  "insert_<random>.idx"
        real pack name: "pack-<SHA1>.pack"
        real index name: "pack-<SHA1>.idx"
        atomic rename tmpPack to realPack
        atomic rename tmpIdx to tmpIdx
  execute commands
  unlock pack by removing .keep file
  trigger auto gc if enabled

When PackInserter.flush() renames the temporary pack to the final
"pack-xxx.pack" file  the temporary pack index file "insert_xxx.idx"
has no matching .pack file with the same base name for a short interval.
If deleteOrphans() ran during that interval it deduced the pack index
file was orphaned. Subsequently the missing pack index caused
MissingObjectExceptions since objects contained in the pack couldn't be
looked up anymore.

Bug: https://bugs.chromium.org/p/gerrit/issues/detail?id=13544
Change-Id: I559c81e4b1d7c487f92a751bd78b987d32c98719
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

DirCacheEditor unconditionally applied a PathEdit to all stages in the
index. This gives wrong results if one wants to check out a file from
some commit to resolve a conflict: JGit would update the working tree
file multiple times (once per stage), and set all stages to point to
the checked-out blob.

C git replaces the stages by the entry for the checked-out file.

To support this, add a DirCacheEntry.setStage() method so that
CheckoutCommand can force the stage to zero. In DirCacheEditor, keep
only the zero stage if the PathEdit re-set the stage.

Bug: 568038
Change-Id: Ic7c635bb5aaa06ffaaeed50bc5e45702c56fc6d1
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

PerformanceLogContext threw NullPointerException when multiple threads
tried to add an event to the PerformanceLogContext. The cause for this
is that the ThreadLocal was initialized only in the class constructor
for the first thread; for subsequent threads it was null.

To fix this initialize eventRecords for each thread.

Change-Id: I18ef67dff8f0488e3ad28c9bbc18ce73d5168cf9
Signed-off-by: Alexa Panfil <alexapizza@google.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Fix IOException occurring when calling
GC on a repository with absent objects/pack folder.

Change-Id: I5be1333a0726f4d7491afd25ddac85451686c30a
Signed-off-by: Nail Samatov <sanail@yandex.ru>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

This problem occurred when calling SubmoduleWalk#getModuleName if the
first submodule processed has a name and a path which do not match
SubmoduleWalk#getModuleName returned the module path instead of the
module name. In order to fix this SubmoduleWalk#getModuleName needs to
ensure that the modules config is loaded.

Bug: 565776
Change-Id: I36ce1fbc64c4849f9d8e39864b825c6e28d344f8
Signed-off-by: John Dallaway <john@dallaway.org.uk>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Add new performance logging to register events of type duration.
The proposed logging is similar to the performance logging
in OS Gerrit https://gerrit-review.googlesource.com/c/gerrit/+/225628:
a global Singleton (LoggingContext in Gerrit) is
collecting the performance logs in a thread-safe events list,
and at the end of the monitored command the list of events is
retrieved and written to a log, after which it is cleared.

What this patch does:
The main component is the Singleton (PerformanceLogContext), which
is used to collect the records (PerformanceLogRecord) in one place
(ThreadLocal eventsList) from anywhere using
PerformanceLogContext.getInstance().addEvent().

Reason why this change is needed:
The current monitoring in JGit has several issues:
1. git fetch and git push events are handled separately
(PackStatistics and ReceivedPackStatistics), with no unified way
of writing or reading the statistics.
2. PostUploadHook is only invoked on the event of sending the
pack, which means that the PackStatistics is not available for
the fetch requests that did not end with sending the pack
(negotiation requests).
3. The way the logs are created is different from the performance
log approach, so the long-running operations need to be collected
from both performance log (for JGit DFS overridden operations and
Gerrit operations) and gitlog (for JGit ones).

The proposed performance logging is going to solve the above
mentioned issues: it collects all of the performance logs in one
place, thus accounting for the commands that do not result in
sending a pack. The logs are compatible with the ones on Gerrit.
Moreover, the Singleton is accessible anywhere in the call stack,
which proved to be successful in other projects like Dapper
(https://research.google/pubs/pub36356/).

Signed-off-by: Alexa Panfil <alexapizza@google.com>
Change-Id: Iabfe667a3412d8a9db94aabb0f39b57f43469c41

This enables jgit to use any refs in the refs/ namespace when describing
commits.

Signed-off-by: Jason Yeo <jasonyeo88@gmail.com>
Change-Id: I1fa22d1c39c0e2f5e4c2938c9751d8556494ac26