Working on builtin-commit

Hi,

To avoid duplication of work, here's a short heads up.  I've started
working on porting git-commit.sh (and status) to builtins.  It's still
work in progress, and nowhere near a full-time effort, but to prevent
doing double work as with builtin-tag, I thought I'd let the list know.
I have a repo over here:

	git://people.freedesktop.org/~krh/git.git

and the code is browsable here:

	http://cgit.freedesktop.org/~krh/git.git

on the 'builtin-commit' branch.

It's just a snapshot of my current progress, so don't slam my lack of
error checking etc just yet.  The work also needs to be split out in a
few patches (eg the read_pipe stuff). One thing that might be
interesting to discuss now, though, is my approach to option parsing.  I
realize real men do this by hand using a lot of strcmp's, but I broke
down and wrote a little option parser.  You give it a pointer to argv
and an array of these:

	struct option {
		enum option_type type;
		const char *long_name;
		char short_name;
		void *value;
	};

with

	enum option_type {
		OPTION_NONE,
		OPTION_STRING,
		OPTION_INTEGER,
		OPTION_LAST
	};

and it goes and parses the command line.  As the shell script, it
accepts all abreviations of long options, eg all of --messa doit,
--message=doit, -mdoit, -m doit, for the long_name="message";
short_name='m' case.  Ambiguous abbreviations are resolved according to
the order the options appears in the array.  I've kept it as simple as
possible and it works well for builtin-commit.c.  It's obviously useful
for other commands, but my goal here is to get git-commit.sh ported to
C, not to host a flamewar over the option parser API and whether we
should port other builtins.

cheers,
Kristian