We were checking for the index file, which is not assured to exist on
clean git repositories.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Disable garbage collection of cross-references to prevent
double-freeing. Internal reference management is now done
with a separate method.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

- Added several missing reference increases
- Add new destructor to the repository that does not GC the objects

Signed-off-by: Vicent Marti <tanoku@gmail.com>

All `git_object` instances looked up from the repository are reference
counted. User is expected to use the new `git_object_close` when an
object is no longer needed to force freeing it.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

The methods previously known as

	git_repository_lookup
	git_repository_newobject
	git_repository_lookup_ref

are now part of their respective namespaces:

	git_object_lookup
	git_object_new
	git_reference_lookup

This makes the API more consistent with the new references API.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

The old hash table with chained buckets has been replaced by a new one
using Cuckoo hashing, which offers guaranteed constant lookup times.
This should improve speeds on most use cases, since hash tables in
libgit2 are usually used as caches where the objects are stored once and
queried several times.

The Cuckoo hash implementation is based off the one in the Basekit
library [1] for the IO language, but rewritten to support an arbritrary
number of hashes. We currently use 3 to maximize the usage of the nodes pool.

[1]: https://github.com/stevedekorte/basekit/blob/master/source/CHash.c

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Fixed several issues with path joining and bare repos.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Signed-off-by: Vicent Marti <tanoku@gmail.com>

The `dirname` and `dirbase` methods have been replaced with the Android
implementation, which is actually compilant to some kind of standard.

A new method `topdir` has been added, which returns the topmost
directory in a path.

These changes fix issue #49:

	`gitfo_prettify_dir_path` converts "./.git/" to ".git/", so
	the code at src/repository.c:190 goes out of bounds when
	trying to find the topmost directory.

	The new `git__topdir` method handles this gracefully, and the
	fixed `git__dirname` now returns the proper value for the
	repository's working dir.

	E.g.

		/repo/.git/ ==> working dir '/repo/'
		.git/		==> working dir '.'

Signed-off-by: Vicent Marti <tanoku@gmail.com>

git_revwalk_next now returns an error code when the iteration is over.
git_repository_index now returns an error code when the index file could
not be opened.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Several changes have been committed to allow the user to create
in-memory references and write back to disk. Peeling of symbolic
references has been made explicit. Added getter and setter methods for
all attributes on a reference. Added corresponding documentation.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

All the commits have been squashed into a single one before refactoring
the final code, to keep everything tidy.

Individual commit messages are as follows:

Added repository reference looking up functionality placeholder.

Added basic reference database definition and caching infrastructure.

Removed useless constant.

Added GIT_EINVALIDREFNAME error and description. Added missing description for GIT_EBAREINDEX.

Added GIT_EREFCORRUPTED error and description.

Added GIT_ETOONESTEDSYMREF error and description.

Added resolving of direct and symbolic references.

Prepared the packed-refs parsing.

Added parsing of the packed-refs file content.

When no loose reference has been found, the full content of the packed-refs file is parsed. All of the new (i.e. not previously parsed as a loose reference) references are eagerly stored in the cached references storage.

The method packed_reference_file__parse() is in deer need of some refactoring. :-)

Extracted to a method the parsing of the peeled target of a tag.

Extracted to a method the parsing of a standard packed ref.

Fixed leaky removal of the cached references.

Ensured that a previously parsed packed reference isn't returned if a more up-to-date loose reference exists.

Enhanced documentation of git_repository_reference_lookup().

Moved some refs related constants from repository.c to refs.h.

Made parsing of a packed tag reference more robust.

Updated git_repository_reference_lookup() documentation.

Added some references to the test repository.

Added some tests covering tag references looking up.

Added some tests covering symbolic and head references looking up.

Added some tests covering packed references looking up.

Made git_repository_open2() and git_repository_open3() benefit from recently added path prettifying function.

Made git_repository_open() and git_repository_init() benefit from recently added path prettifying function.

In-memory tree objects were not being properly initialized, because the
internal entries vector was created on the 'parse' method.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Lets the user specify the ODB that will be used by the repository
manually.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

All the relevant git_object methods have been moved to object.c

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Keep all the repository init code as static.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Implemented recursive directory creation
Fix style issues

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Libgit2 is now officially include as

	#include "<git2.h>"

or indidividual files may be included as

	#include <git2/index.h>

Signed-off-by: Vicent Marti <tanoku@gmail.com>

The maze with include dependencies has been fixed.
There is now a global include:

	#include <git.h>

The git_odb_backend API has been exposed.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Comes with two default backends: loose object and packfiles.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Replaced magic number "0" with GIT_SUCCESS constant wherever it made sense.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

Signed-off-by: Vicent Marti <tanoku@gmail.com>