From: Duy Nguyen <pclouds@gmail.com>
To: Luke Robison <robison@arlut.utexas.edu>
Cc: Git Mailing List <git@vger.kernel.org>
Subject: Re: Understanding Binary Deltas within Packfile
Date: Tue, 20 Mar 2018 20:12:05 +0100 [thread overview]
Message-ID: <CACsJy8ChV5sXV7N0+N0y9ehO56UCJ8fuqjFbHbbnez35P5af4g@mail.gmail.com> (raw)
In-Reply-To: <751c0493-435c-4a98-4d1c-e3d6677c62d8@arlut.utexas.edu>
On Tue, Mar 20, 2018 at 7:34 PM, Luke Robison <robison@arlut.utexas.edu> wrote:
> On 3/20/2018 11:03 AM, Duy Nguyen wrote:
>>
>> On Tue, Mar 20, 2018 at 4:43 PM, Luke Robison <robison@arlut.utexas.edu>
>> wrote:
>>>
>>> Is there any documentation of the contents of the binary delta datain a
>>> packfile, and how to interpret them? I found
>>>
>>> https://github.com/git/git/blob/master/Documentation/technical/pack-format.txt
>>> documenting the packfile itself, but the "compressed delta data" seems
>>> largely undocumented. The source code of
>>> https://github.com/git/git/blob/master/diff-delta.c is pretty dense.
>>
>> The output is consumed by patch_delta() in patch-delta.c if I'm not
>> mistaken. This function is less than 100 lines, probably much easier
>> to see the delta format.
>
> Thank you, that was much easier to read, and I've got my prototype working
> now. I also found this site to be quite helpful:
> http://stefan.saasen.me/articles/git-clone-in-haskell-from-the-bottom-up/#delta_encoding
By the way, I forgot to add, if you want to improve pack-format.txt
(since you study it anyway), patches are always welcome.
--
Duy
prev parent reply other threads:[~2018-03-20 19:12 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-20 15:43 Understanding Binary Deltas within Packfile Luke Robison
2018-03-20 16:03 ` Duy Nguyen
2018-03-20 18:34 ` Luke Robison
2018-03-20 19:12 ` Duy Nguyen [this message]
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