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Re: Understanding Binary Deltas within Packfile

From
LRLuke Robison <robison@arlut.utexas.edu>
Date
Mar 20, 2018, 18:34 UTC
Message-ID
<751c0493-435c-4a98-4d1c-e3d6677c62d8@arlut.utexas.edu>
In-Reply-To
<CACsJy8ABgZy=eJ7niUysb2XZ3qUr3J+jmh_5YWZ1ZDiFCrb0tA@mail.gmail.com>
On 3/20/2018 11:03 AM, Duy Nguyen wrote:
Show 10 quoted lines
> 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

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Message 3 of 4 in “Understanding Binary Deltas within Packfile”
  1. Luke RobisonMar 20, 2018
  2. Duy NguyenMar 20, 2018
  3. Luke RobisonMar 20, 2018
  4. Duy NguyenMar 20, 2018

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