SYNOPSIS

pristine-tar [-vdk] gendelta tarball delta

pristine-tar [-vdk] gentar delta tarball

pristine-tar [-vdk] [-m message] commit tarball [upstream]

pristine-tar [-vdk] checkout tarball

pristine-tar [-vdk] list

DESCRIPTION

pristine-tar can regenerate an exact copy of a pristine upstream tarball using only a small binary delta file and the contents of the tarball, which are typically kept in an upstream branch in version control.

The delta file is designed to be checked into version control along-side the upstream branch, thus allowing Debian packages to be built entirely using sources in version control, without the need to keep copies of upstream tarballs.

pristine-tar supports compressed tarballs, calling out to pristine-gz(1), pristine-bz2(1), and pristine-xz(1) to produce the pristine gzip, bzip2, and xz files.

COMMANDS

pristine-tar gendelta tarball delta

This takes the specified upstream tarball, and generates a small binary delta file that can later be used by pristine-tar gentar to recreate the tarball.

If the delta filename is ``-'', it is written to standard output.

pristine-tar gentar delta tarball

This takes the specified delta file, and the files in the current directory, which must have identical content to those in the upstream tarball, and uses these to regenerate the pristine upstream tarball.

If the delta filename is ``-'', it is read from standard input.

pristine-tar commit tarball [upstream]

pristine-tar commit generates a pristine-tar delta file for the specified tarball, and commits it to version control. The pristine-tar checkout command can later be used to recreate the original tarball based only on the information stored in version control.

The upstream parameter specifies the tag or branch that contains the same content that is present in the tarball. This defaults to ``refs/heads/upstream'', or if there's no such branch, any branch matching ``upstream''. The name of the tree it points to will be recorded for later use by pristine-tar checkout. Note that the content does not need to be 100% identical to the content of the tarball, but if it is not, additional space will be used in the delta file.

The delta files are stored in a branch named ``pristine-tar'', with filenames corresponding to the input tarball, with ``.delta'' appended. This branch is created or updated as needed to add each new delta.

If tarball already exists previously, it will only be overwritten if it does not match a hash of the tarball that has been committed to version control.

pristine-tar checkout tarball

This regenerates a copy of the specified tarball using information previously saved in version control by pristine-tar commit.

pristine-tar list

This lists tarballs that pristine-tar is able to checkout from version control.

pristine-tar verify tarball

Verifies whether an existing tarball matches the one that has been committed to version control.

OPTIONS

-v

--verbose

Verbose mode, show each command that is run.

-d

--debug

Debug mode.

-k

--keep

Don't clean up the temporary directory on exit.

-m message

--message=message

Use this option to specify a custom commit message to pristine-tar commit.

EXAMPLES

Suppose you maintain the hello package, in a git repository. You have just created a tarball of the release, hello-1.0.tar.gz, which you will upload to a ``forge'' site.

You want to ensure that, if the ``forge'' loses the tarball, you can always recreate exactly that same tarball. And you'd prefer not to keep copies of tarballs for every release, as that could use a lot of disk space when hello gets the background mp3s and user-contributed levels you are planning for version 2.0.

The solution is to use pristine-tar to commit a delta file that efficiently stores enough information to reproduce the tarball later.

        cd hello
        git tag -s 1.0
        pristine-tar commit ../hello-1.0.tar.gz 1.0

Remember to tell git to push both the pristine-tar branch, and your tag:

        git push --all --tags

Now it is a year later. The worst has come to pass; the ``forge'' lost all its data, you deleted the tarballs to make room for bug report emails, and you want to regenerate them. Happily, the git repository is still available.

        git clone git://github.com/joeyh/hello.git
        cd hello
        pristine-tar checkout ../hello-1.0.tar.gz

LIMITATIONS

Only tarballs, gzipped tarballs, bzip2ed tarballs, and xzed tarballs are currently supported.

Currently only the git revision control system is supported by the ``checkout'' and ``commit'' commands. It's ok if the working copy is not clean or has uncommitted changes, or has changes staged in the index; none of that will be touched by ``checkout'' or ``commit''.

AUTHOR

Joey Hess <[email protected]>

Licensed under the GPL, version 2 or above.