This adds a simple wrapper around the iconv APIs and uses it
instead of the old code that was inlining the iconv stuff. This
makes it possible for me to test the iconv logic in isolation.
A "no iconv" version of the API was defined with macros so that
I could have fewer ifdefs in the code itself.
This makes it easy to take a buffer containing a path with relative
references (i.e. .. or . path segments) and resolve all of those
into a clean path. This can be applied to URLs as well as file
paths which can be useful.
As part of this, I made the drive-letter detection apply on all
platforms, not just windows. If you give a path that looks like
"c:/..." on any platform, it seems like we might as well detect
that as a rooted path. I suppose if you create a directory named
"x:" on another platform and want to use that as the beginning
of a relative path under the root directory of your repo, this
could cause a problem, but then it seems like you're asking for
trouble.
This updates to the latest clar which includes the helpers
`cl_assert_equal_s` and `cl_assert_equal_i`. Convert the code
over to use those and remove the old libgit2-only helpers.
This makes so much sense that I can't believe it hasn't been done
before. Kill the old `git_fbuffer` and read files straight into
`git_buf` objects.
Also: In order to fully support 4GB files in 32-bit systems, the
`git_buf` implementation has been changed from using `ssize_t` for
storage and storing negative values on allocation failure, to using
`size_t` and changing the buffer pointer to a magical pointer on
allocation failure.
Hopefully this won't break anything.
