Also make the return value of "cache_name_pos()" be sane: positive
or zero if we found it (it's the index into the cache array), and
"-pos-1" to indicate where it should go if we didn't.
It now requires the "--add" flag before you add any new files, and
a "--remove" file if you want to mark files for removal. And giving
it the "--refresh" flag makes it just update all the files that it
already knows about.
It's got some debugging printouts etc still in it, but testing on the
kernel seems to show that it does indeed fix the issue with huge tree
files for each commit.
It finds the cache entry position for a given name, and is
generally useful. Sure, everybody can just scan the active
cache array, but since it's sorted, you actually want to
search it with a binary search, so let's not duplicate that
logic all over the place.
Patches from Dave Jones and Ingo Molnar, but since I don't have any
infrastructure in place to use the old patch applicator scripts I
am trying to build up, I ended up fixing the thing by hand instead.
Credit where credit is due, though. Nice to see that people are
taking a look at the project even in this early stage.
The tool interface sucks (especially "committing" information, which is just
me doing everything by hand from the command line), but I think this is in
theory actually a viable way of describing the world. So copyright it.
