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Re: Git Community Book

From
Linus Torvalds <torvalds@linux-foundation.org>
Date
Sep 5, 2008, 20:27 UTC
Message-ID
<alpine.LFD.1.10.0809051317510.3117@nehalem.linux-foundation.org>
In-Reply-To
<d411cc4a0809051208k2a15c4a7te09a6979929e52f7@mail.gmail.com>
On Fri, 5 Sep 2008, Scott Chacon wrote:
> 
> http://book.git-scm.com/7_the_packfile.html

The checksums in the index file "trailers" are all claiming to be 4 bytes, and that's wrong - they're full SHA1 sums at 20 bytes each.

The v2 pack-file _also_ has per-object CRC's, and those are indeed just 4 bytes each, and are correctly listed as such.

The pack-file itself also has a few more things there, it's not just the "PACK" string and then the objects. It has two more 32-bit words: a pack file version number and the number of entries in the pack-file (all network byte order). It also has its own checksum at the end (20-byte SHA1 again).

But looks good otherwise from a quick look.
		Linus
Previous: Scott ChaconNext: Stephan Beyer
Message 9 of 11 in “Git Community Book”
  1. Scott ChaconSep 5, 2008
  2. Thomas AdamSep 5, 2008
  3. Scott ChaconSep 5, 2008
  4. Junio C HamanoSep 5, 2008
  5. Scott ChaconSep 5, 2008
  6. Felipe ContrerasSep 5, 2008
  7. Shawn O. PearceSep 6, 2008
  8. Scott ChaconSep 6, 2008
  9. Linus TorvaldsSep 5, 2008
  10. Stephan BeyerSep 6, 2008
  11. Christos ΤrochalakisSep 6, 2008

Read the whole thread, see it on lore, or plain text.

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