Assigning Git SHA1's without Git

Posted by git-noob on Stack Overflow See other posts from Stack Overflow or by git-noob
Published on 2009-02-16T08:53:23Z Indexed on 2010/04/01 1:13 UTC
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git

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sha1

As I understand it when Git assigns a SHA1 hash to a file this SHA1 is unique to the file based on its contents.

As a result if a file moves from one repository to another the SHA1 for the file remains the same as its contents have not changed.

How does Git calculate the SHA1 digest? Does it do it on the full uncompressed file contents?

I would like to emulate assigning SHA1's outside of Git.

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