commit | 05fd01656ee295e4a8d3c1efff0ca3a6f48c1f4c | [log] [tgz] |
---|---|---|
author | Marco Miller <marco.miller@ericsson.com> | Wed Apr 20 17:42:34 2016 -0400 |
committer | Matthias Sohn <matthias.sohn@sap.com> | Thu May 05 00:49:44 2016 +0200 |
tree | f5cc10ca58ac98b090c091b73d5e77b78bbcf732 | |
parent | ddc0e9e84abf88701c32c1947fe536050a0b1043 [diff] |
Scan loose ref before packed in case gc about to remove the loose Before this change, jgit used to read packed-refs before scanning loose refs. That was not a problem if gc didn't run concurrently. When gc did run concurrently with such refs reading, that order sometimes broke the latter. This lead to reading an older version of a ref's tip, which meant "losing" the real tip or commit. The specific read-Vs-gc concurrency scenario which broke reading that way follows: 1. let ref R be in packed-refs and R' be in loose 2. jgit starts reading packed-refs 3. gc also starts its business around that very time 4. jgit still has the time to read R from packed-refs 5. as gc is not done yet updating packed-refs with R' 6. jgit then starts scanning loose refs (or is about to) 7. gc quickly ends up being done moving loose R' to packed-refs 8. so gc (quickly) removes loose refs 9. -while jgit is scanning loose refs, now gone 10. so jgit assumes no loose to consider => packed-refs winning 11. so jgit wrongfully returns R (from 4.) as the tip, instead of R'. This fix switches the order so loose refs are scanned (secured) before taking the time to read packed-refs. This way, knowledge of the likelier tip is guaranteed for ref reading to return the true tip - despite concurrent gc. If there is no loose ref to scan, jgit reads packed-refs and lands on R' (or S), which it then returns, as expected. The gerrit issue [1] should be solved by this fix. [1] https://code.google.com/p/gerrit/issues/detail?id=2302 Change-Id: Ibd120120a361a3a6ed565f3836afc1db706fbcdd Signed-off-by: Marco Miller <marco.miller@ericsson.com> Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
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.java7
Extensions for users of Java 7.
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.java7.test
Unit tests for Java 7 specific features
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, but only if you are using Java 7 or newer and include the org.eclipse.jgit.java7 jar/bundle in the classpath, 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 7 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/
org.eclipse.jgit.java7/
Support for symbolic links.
Optimizations for reading file system attributes
org.eclipse.jgit.ant/
org.eclipse.jgit.archive/
org.eclipse.http.*/
There are some missing features:
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See the EGit Contributor Guide:
http://wiki.eclipse.org/EGit/Contributor_Guide
More information about Git, its repository format, and the canonical C based implementation can be obtained from the Git website: