Updated both patches.

  * Moved the changes to pageinspect into the TLI patch, because it
makes more sense to be a part of that patch and it also reduces the size
of the main checksums patch.
  * Fix off-by-one bug in checksum calculation
  * Replace "VerificationInfo" in the function names with "Checksum",
which is shorter.
  * Make the checksum algorithm process 4 bytes at a time and sum into a
signed 64-bit int, which is faster than byte-at-a-time. Also, forbid
zero in either byte of the checksum, because that seems like a good

I've done quite a bit of testing at this point, and everything seems
fine to me. I've tested various kinds of errors (bytes being modified or
zeroed at various places of the header and data areas, transposed pages)
at 8192 and 32768 page sizes. I also looked at the distribution of
checksums in various ways (group by checksum % <prime> for various
primes, and not seeing any skew), and I didn't see any worrying

        Jeff Davis

Attachment: replace-tli-with-checksums-20121125.patch.gz
Description: GNU Zip compressed data

Attachment: checksums-20121125.patch.gz
Description: GNU Zip compressed data

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