From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <junkio@cox.net>
Subject: Re: [PATCH] denser delta header encoding
Date: Tue, 28 Jun 2005 21:58:56 -0700
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Cc: Linus Torvalds <torvalds@osdl.org>, git@vger.kernel.org
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To: Nicolas Pitre <nico@cam.org>
In-Reply-To: <Pine.LNX.4.63.0506290021050.1667@localhost.localdomain> (Nicolas Pitre's message of "Wed, 29 Jun 2005 00:27:45 -0400 (EDT)")
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Linus, please do not apply this as is.

There are code other than what Nico updated with this patch in
sha1_file.c that also need updating, that count the number of
bytes in the delta-patch result by reading from the delta
header.

I wonder if we can have a helper function in delta suite
somewhere (maybe in diff-delta.c):

    int look_at_delta_header(void **delta_data, ulong delta_size,
    	                     ulong *src_size, ulong *dst_size)

that:

    - checks delta size and barf if it is small;
    - reads the header and fills src_size and dst_size;
    - advances *delta_data pointer;

and have count-delta, patch-delta and sha1_file.c users use it
consistently.  Nico, what do you think?