sha1 of the repo excluding history ?

sha1 of the repo excluding history ?

[Yakov Lerner]

    Can I obtain from git the sha1 of the total last state of the
repo excluding history ? This is a state that covers contents and
names of all files and dirs, and x perm of files;
but excludes history, timestamps, ownerhisp, and inode numbers.

That would be approximately like the slow method:
          'find | egrep -v '/\.git(/|$)' | sort | Xcpio -o | sha1sum -'
(imagining Xcpio that does not archive any ownership, timestamps,
and inode numbers). Can I obtain this result immediately from git ?

Yakov

Re: sha1 of the repo excluding history ?

[Shawn O. Pearce]

Yakov Lerner <iler.ml@gmail.com> wrote:
>    Can I obtain from git the sha1 of the total last state of the
> repo excluding history ? This is a state that covers contents and
> names of all files and dirs, and x perm of files;
> but excludes history, timestamps, ownerhisp, and inode numbers.
> 
> That would be approximately like the slow method:
>          'find | egrep -v '/\.git(/|$)' | sort | Xcpio -o | sha1sum -'
> (imagining Xcpio that does not archive any ownership, timestamps,
> and inode numbers). Can I obtain this result immediately from git ?

	git rev-parse HEAD^{tree}

The trick here is ^{tree}; this operator takes a commit-ish (commit
or tag) and returns the SHA-1 of the tree that the commit-ish
points at.  That SHA-1 is the SHA-1 of the file contents, names,
and executable bits, but nothing else.  No history.

I use it sometimes after a rebase when I reorganize history:

	old=`git rev-parse HEAD^{tree}`
	.... do rebasing magick ...
	test $old = `git rev-parse HEAD^{tree}` && echo GOOD

If I don't get back GOOD then I know I somehow changed the files in
a way that isn't what I had before, and that wasn't what I wanted
if all I was doing was cleaning up commit messages.

-- 
Shawn.

Re: sha1 of the repo excluding history ?

[Junio C Hamano]

"Yakov Lerner" <iler.ml@gmail.com> writes:

>    Can I obtain from git the sha1 of the total last state of the
> repo excluding history ? This is a state that covers contents and
> names of all files and dirs, and x perm of files;
> but excludes history, timestamps, ownerhisp, and inode numbers.
>
> That would be approximately like the slow method:
>          'find | egrep -v '/\.git(/|$)' | sort | Xcpio -o | sha1sum -'
> (imagining Xcpio that does not archive any ownership, timestamps,
> and inode numbers). Can I obtain this result immediately from git ?
>
> Yakov

I think you are talking about tree object name.  git-cat-file
commit HEAD and look at "tree xxx" line.

You can use "git tar-tree $tree_object_name" to tar it up,
and "git ls-tree -r $tree_object_name" to list all the blob
object names with their perms.