From: Jeff King <peff@peff.net>
Date: Wed, 09 Nov 2016 03:34:41 GMT
Subject: Re: Bug: git config does not respect read-only .gitconfig file
Message-ID: <20161109033441.hp4eyf5qahimrtr3@sigill.intra.peff.net>
In-Reply-To: <xmqqk2cdbg5v.fsf@gitster.mtv.corp.google.com>

On Tue, Nov 08, 2016 at 05:22:52PM -0800, Junio C Hamano wrote:

> Jeff King <peff@peff.net> writes:
> 
> > Probably converting "rename(from, to)" to first check "access(to,
> > W_OK)". That's racy, but it's the best we could do.
> 
> Hmph, if these (possibly problematic) callers are all following the
> usual "lock, write to temp, rename" pattern, perhaps the lock_file()
> function can have access(path, W_OK) check before it returns a
> tempfile that has been successfully opened?

Yeah, that is a lot friendlier, as it prevents the caller from doing
work (which may even involve the user typing things!) when it is clear
that we would fail the final step anyway.

-Peff