| commit | 1484d6eb0ac36dc8e31f5069b77e4ecfd573ad17 | [log] [tgz] |
|---|---|---|
| author | Jonathan Nieder <jrn@google.com> | Thu Apr 26 15:14:50 2018 -0700 |
| committer | Jonathan Nieder <jrn@google.com> | Thu Apr 26 15:54:39 2018 -0700 |
| tree | 3d7efca2df18c6d26708e2af0a79e834b48d4798 | |
| parent | e8e456b519708aca430b998bf69ff3f214628c31 [diff] |
LargePackedWholeObject: Do not reuse released inflater
LargePackedWholeObject.openStream produces a stream that allows
reading a large object. This stream holds a DfsReader that takes care
of caching delta bases etc and in particular holds zlib Inflater for
use while reading the each delta in the packfile.
At DfsReader creation time, the Inflater is acquired from a global
InflaterCache to avoid initialization overhead in case there is an
existing Inflater available for reuse. When done with the Inflater,
the DfsReader is responsible for returning it to the cache for reuse.
The DfsReader is AutoClosable to remind the caller to close it and
release the Inflater when finished with it.
b0ac5f9c8907a4034612543a92eb465e88a9c6f2 (LargePackedWholeObject:
Refactor to open DfsReader in try-with-resource, 2018-04-11) tried to
clarify the lifetime of the DfsReader but was too aggressive: when
this function returns, PackInputStream owns the DfsReader and is
already going to release it. Worse, the returned InflaterInputStream
holds a reference to the DfsReader's inflater, making releasing the
DfsReader not only unnecessary but unsafe.
The Inflater gets released into the InflaterCache's pool, to be
acquired by another caller that uses it concurrently with the
InflaterInputStream. This results in errors, such as
java.util.zip.ZipException: incorrect header check
at java.util.zip.InflaterInputStream.read(InflaterInputStream.java:164)
at java.util.zip.InflaterInputStream.skip(InflaterInputStream.java:208)
at java.io.BufferedInputStream.skip(BufferedInputStream.java:377)
and
java.util.zip.DataFormatException: incorrect header check
at java.util.zip.Inflater.inflateBytes(Native Method)
at java.util.zip.Inflater.inflate(Inflater.java:259)
at org.eclipse.jgit.internal.storage.dfs.DfsReader.inflate(DfsReader.java:783)
at org.eclipse.jgit.internal.storage.dfs.DfsPackFile.decompress(DfsPackFile.java:420)
at org.eclipse.jgit.internal.storage.dfs.DfsPackFile.load(DfsPackFile.java:767)
and
Caused by: java.util.zip.ZipException: incorrect header check
at java.util.zip.InflaterInputStream.read(InflaterInputStream.java:164)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:246)
at java.io.BufferedInputStream.read1(BufferedInputStream.java:286)
at java.io.BufferedInputStream.read(BufferedInputStream.java:345)
at org.eclipse.jgit.lib.ObjectStream$Filter.read(ObjectStream.java:219)
at org.eclipse.jgit.util.IO.readFully(IO.java:233)
at org.eclipse.jgit.transport.PackParser.checkObjectCollision(PackParser.java:1173)
Verified in production. It should be possible to make a
straightforward unit test for this using the InflaterCache state but
that can wait for a followup commit.
Change-Id: Iaf1d6fd368b64f76c520d215fd270a6098a1f236
An implementation of the Git version control system in pure Java.
This package is licensed under the EDL (Eclipse Distribution License).
JGit can be imported straight into Eclipse, built and tested from there, but the automated builds use Maven.
org.eclipse.jgit
A pure Java library capable of being run standalone, with no additional support libraries. It provides classes to read and write a Git repository and operate on a working directory.
All portions of JGit are covered by the EDL. Absolutely no GPL, LGPL or EPL contributions are accepted within this package.
org.eclipse.jgit.ant
Ant tasks based on JGit.
org.eclipse.jgit.archive
Support for exporting to various archive formats (zip etc).
org.eclipse.jgit.http.apache
Apache httpclient support
org.eclipse.jgit.http.server
Server for the smart and dumb Git HTTP protocol.
org.eclipse.jgit.pgm
Command-line interface Git commands implemented using JGit (“pgm” stands for program).
org.eclipse.jgit.packaging
Production of Eclipse features and p2 repository for JGit. See the JGit Wiki on why and how to use this module.
org.eclipse.jgit.junit
Helpers for unit testing
org.eclipse.jgit.test
Unit tests for org.eclipse.jgit
org.eclipse.jgit.ant.test
org.eclipse.jgit.pgm.test
org.eclipse.jgit.http.test
org.eclipse.jgit.junit.test
No further description needed
Native smbolic links are supported, provided the file system supports them. For Windows you must have Windows Vista/Windows 2008 or newer, use a non-administrator account and have the SeCreateSymbolicLinkPrivilege.
Only the timestamp of the index is used by jgit if the index is dirty.
JGit requires at least a Java 8 JDK.
CRLF conversion is performed depending on the core.autocrlf setting, however Git for Windows by default stores that setting during installation in the “system wide” configuration file. If Git is not installed, use the global or repository configuration for the core.autocrlf setting.
The system wide configuration file is located relative to where C Git is installed. Make sure Git can be found via the PATH environment variable. When installing Git for Windows check the “Run Git from the Windows Command Prompt” option. There are other options like Eclipse settings that can be used for pointing out where C Git is installed. Modifying PATH is the recommended option if C Git is installed.
We try to use the same notation of $HOME as C Git does. On Windows this is often not the same value as the user.home system property.
org.eclipse.jgit/
Read loose and packed commits, trees, blobs, including deltafied objects.
Read objects from shared repositories
Write loose commits, trees, blobs.
Write blobs from local files or Java InputStreams.
Read blobs as Java InputStreams.
Copy trees to local directory, or local directory to a tree.
Lazily loads objects as necessary.
Read and write .git/config files.
Create a new repository.
Read and write refs, including walking through symrefs.
Read, update and write the Git index.
Checkout in dirty working directory if trivial.
Walk the history from a given set of commits looking for commits introducing changes in files under a specified path.
Object transport Fetch via ssh, git, http, Amazon S3 and bundles. Push via ssh, git and Amazon S3. JGit does not yet deltify the pushed packs so they may be a lot larger than C Git packs.
Garbage collection
Merge
Rebase
And much more
org.eclipse.jgit.pgm/
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org.eclipse.jgit.archive/
org.eclipse.http.*/
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