From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Shawn O. Pearce" <spearce@spearce.org>
Subject: Re: [PATCH] fix simple deepening of a repo
Date: Wed, 26 Aug 2009 01:22:56 -0700
Message-ID: <20090826082256.GO1033@spearce.org>
References: <alpine.LNX.2.00.0908240144530.28290@iabervon.org> <alpine.LNX.2.00.0908242212260.26869@reaper.quantumfyre.co.uk> <alpine.LFD.2.00.0908242001250.6044@xanadu.home> <20090825021223.GE1033@spearce.org> <7vab1osc2m.fsf@alter.siamese.dyndns.org> <20090825061248.GG1033@spearce.org> <7vy6p8pfm1.fsf@alter.siamese.dyndns.org> <20090825151424.GJ1033@spearce.org> <20090826021057.GL1033@spearce.org> <4A94DF84.4050906@viscovery.net>
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Cc: Junio C Hamano <gitster@pobox.com>, Nicolas Pitre <nico@cam.org>,
	Julian Phillips <julian@quantumfyre.co.uk>,
	Daniel Barkalow <barkalow@iabervon.org>,
	Johannes Schindelin <Johannes.Schindelin@gmx.de>,
	git@vger.kernel.org
To: Johannes Sixt <j.sixt@viscovery.net>
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Johannes Sixt <j.sixt@viscovery.net> wrote:
> Shawn O. Pearce schrieb:
> >  static void upload_pack(void)
> >  {
> >  	reset_timeout();
> > -	head_ref(send_ref, NULL);
> > -	for_each_ref(send_ref, NULL);
> > -	packet_flush(1);
> > +	head_ref(scan_ref, NULL);
> > +	for_each_ref(scan_ref, NULL);
> > +
> > +	push_advertise("HEAD");
> > +	push_advertise("refs/heads/*");
> > +	push_advertise("refs/tags/*");
> > +	send_refs();
> > +
> 
> How will this mesh with 'git clone --mirror'?

Not well.

> Is the client expected to
> ask with 'expand refs/*'?

If the client is new enough to understand the "expand" extension,
yes, it would ask for "expand refs/*" and get everthing, allowing
it to complete a full mirror.

If the client is older and doesn't know this extension, then it
is hopeless.  The server isn't advertising refs/*, doesn't know
that the client can't ask for refs/*, and the client doesn't know
it is missing refs when it makes the mirror.

This backwards incompatible breakage is something I have no real
solution for.  :-|

-- 
Shawn.