On Thu, Mar 29, 2018 at 05:19:04PM +0200, Johannes Schindelin wrote:

Technically, it is the git_config_set_multivar_in_file_gently()
function that we modify here (but the oneline would get too long if we
were that precise).

This change prepares the git_config_set machinery to allow reusing empty
sections, by using the file-local function do_config_from_file()
directly (whose signature can then be changed without any effect outside
of config.c).

An incidental benefit is that we avoid a level of indirection, and we
also avoid calling flockfile()/funlockfile() when we already know that
we are not operating on stdin/stdout here.

I'm not sure I understand that last paragraph. What does flockfile() have
to do with stdin/stdout?

The point of those calls is that we're locking the FILE handle, so that
it's safe for the lower-level config code to run getc_unlocked(), which
is faster.

So without those, we're calling getc_unlocked() without holding the
lock. I think it probably works in practice because we know that we're
single-threaded, but it seems a bit sketchy.

-Peff