Re: How to properly find git config in a libgit.a-using executable?

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi Peff & Mike,

On Fri, 22 Mar 2019, Jeff King wrote:

> On Wed, Mar 20, 2019 at 07:19:41PM +0900, Mike Hommey wrote:
>
> > I thought of a few options (it's worth noting the helper is invoked in a
> > way that makes $GIT_EXEC_PATH set, which can help a little):
> > - spawn `$GIT_EXEC_PATH/git-config -l -z`, parse its output, and set the
> >   internal config from that. That's the barbarian option.
> > - build the helper with RUNTIME_PREFIX, and modify the RUNTIME_PREFIX
> >   code to use $GIT_EXEC_PATH if it's set, rather than the path the
> >   executable is in. That actually sounds reasonable enough that I'd send
> >   a patch for git itself. But that doesn't quite address the nitpick case
> >   where ETC_GITCONFIG could be either `/etc/gitconfig` or
> >   `etc/gitconfig` depending how git was compiled, and there's no way to
> >   know which is the right one.
>
> I'm not entirely sure I understand the problem, but it sounds like you
> want to know the baked-in ETC_GITCONFIG for a built version of git (that
> isn't necessarily the one that shares your build of libgit.a).
>
> There's no direct way to have Git print that out. It would be reasonable
> to add one to rev-parse, I think.
>
> Barring that, here's a hack:
>
>   git config --system --show-origin --list -z |
>   perl -lne '/^file:(.*?)\0/ and print $1 and exit 0'
>
> If the file is empty, it won't print anything, of course. But then,
> you'd know that it also has no config in it. :)

How about

	GIT_EDITOR=echo git config --system -e 2>/dev/null

It will error out if the directory does not exist, for some reason, e.g.
when you installed Git in your home directory via `make install` from a
fresh clone. So you'll have to cope with that contingency.

Ciao,
Dscho