RSYNC algorithm

[Ravi Chunduru]

Hi,

I am tring to understand the code. Correct me if I am wrong.

I did not find any MD5 or MD5 hash calculation.
One of the ways RSYNC algorithm ensures that duplicate data is by
rechecking with the stronger checksum using MD5 or MD4 after matching
up with the rolling checksum (weak checksum).  I did not find anywhere
in the code of this additional check.  I understand that the encoder
is taking care of this issue by comparing the new & stored block data.
  What I am not sure is how decoder is ensuring that it is not picking
up the wrong data (matching the weak checksum)?  From my little
understanding of the code, it apperas that encoder is sending the weak
checksum to the decoder whenever there is a match on the encoder.

Thanks
Ravi