This fix makes libgit2 capable of parsing annotated tag objects that lack
the optional message/description field.
Previously, libgit2 treated this field as mandatory and raised a tag_error on
such tags. However, the message field is optional.
An example of such a tag is refs/tags/v2.6.16.31-rc1 in Linux:
$ git cat-file tag refs/tags/v2.6.16.31-rc1
object afaa018cefb6af63befef1df7d8febaae904434f
type commit
tag v2.6.16.31-rc1
tagger Adrian Bunk <bunk@stusta.de> 1162716505 +0100
$
This improves docs in some of the public header files, cleans
up and improves some of the example code, and fixes a couple
of pedantic warnings in places.
This adds a new API that allows users to reload the config if the
file has changed on disk. A new config callback function to
refresh the config was added.
The modified time and file size are used to test if the file needs
to be reloaded (and are now stored in the disk backend object).
In writing tests, just using mtime was a problem / race, so I
wanted to check file size as well. To support that, I extended
`git_futils_readbuffer_updated` to optionally check file size in
addition to mtime, and I added a new function `git_filebuf_stats`
to fetch the mtime and size for an open filebuf (so that the
config could be easily refreshed after a write).
Lastly, I moved some similar file checking code for attributes
into filebuf. It is still only being used for attrs, but it
seems potentially reusable, so I thought I'd move it over.
This improves the naming for the rename related functionality
moving it to be called `git_diff_find_similar()` and renaming
all the associated constants, etc. to make more sense.
I also moved the new code (plus the existing `git_diff_merge`)
into a new file `diff_tform.c` where I can put new functions
related to manipulating git diff lists.
This also updates the implementation significantly from the
last revision fixing some ordering issues (where break-rewrite
needs to be handled prior to copy and rename detection) and
improving config option handling.
