[GSoC] libgit2 before the first evaluation

Hello everybody,

the first coding period of this year's Summer of Code is almost over, and the libgit2 project is looking good. Here's a short status update:

All the functionality for revision walking is in place in the main development branch [1]; together with it there's a set of extra functionality: a work in progress interface to load tree objects in memory, and a finished interface to load commits in memory and extract detailed information from them. All this code has been reviewed for style and fixed accordingly (thanks Ramsay), and is in the process of being reviewed for design. The libgit2 core developers have been very busy lately, so any input on this matter is very much welcome.

Furthermore, while waiting for code reviews I've created a new development branch [2] and began working on the features required for the second period of the Summer of Code. So far, there's support for loading and parsing index files from disk; there is also a WIP implementation of git-like atomic file locking [3] which will be required for writing the index files back to disk.

I've been having some issues with file locking, however, since the
reference git.git implementation differs quite a bit from the one on
JGit: it seems like JGit applies an additional filesystem-level lock
(i.e. POSIX flock()) to the temporary ".lock" file, something which is
complicated to do in a cross-platform manner in C. There's also
differences between implementations which I'm trying to work out (not
easy since I'm no Java expert): for instance, it seems like the JGit
implementation doesn't update its internal state to signal that the
file is unlocked after a commit (LockFile.java:393). Are there any
JGit developers who can throw some insight into this?

Either way, once the atomic file locking issues have been solved, I'll get started on the remaining functionality for working with index files (modifying & writing back to disk) . After that, the last goal for the Summer is the API for reference manipulation which hasn't been designed yet. I'll keep you all updated.

Thanks for your time, Vicent Martí http://www.bellverde.org

[1]: http://github.com/tanoku/libgit2-gsoc2010/commits/gsoc [2]: http://github.com/tanoku/libgit2-gsoc2010/commits/gsoc-index [3]: http://github.com/tanoku/libgit2-gsoc2010/commit/8b92be06f64c04c2b2d874cf00769a7deb9a2835