From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Mackall Subject: Mercurial vs Updated git HOWTO for kernel hackers Date: Thu, 23 Jun 2005 16:56:34 -0700 Message-ID: <20050623235634.GC14426@waste.org> References: <42B9E536.60704@pobox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linux Kernel , Git Mailing List , mercurial@selenic.com X-From: git-owner@vger.kernel.org Fri Jun 24 01:54:42 2005 Return-path: Received: from vger.kernel.org ([12.107.209.244]) by ciao.gmane.org with esmtp (Exim 4.43) id 1DlbWb-00008b-Kb for gcvg-git@gmane.org; Fri, 24 Jun 2005 01:54:26 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262905AbVFWX7U (ORCPT ); Thu, 23 Jun 2005 19:59:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262881AbVFWX7U (ORCPT ); Thu, 23 Jun 2005 19:59:20 -0400 Received: from waste.org ([216.27.176.166]:50127 "EHLO waste.org") by vger.kernel.org with ESMTP id S262928AbVFWX4h (ORCPT ); Thu, 23 Jun 2005 19:56:37 -0400 Received: from waste.org (localhost [127.0.0.1]) by waste.org (8.13.4/8.13.4/Debian-3) with ESMTP id j5NNuZqV030453 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Thu, 23 Jun 2005 18:56:35 -0500 Received: (from oxymoron@localhost) by waste.org (8.13.4/8.13.4/Submit) id j5NNuYPS030450; Thu, 23 Jun 2005 18:56:34 -0500 To: Jeff Garzik Content-Disposition: inline In-Reply-To: <42B9E536.60704@pobox.com> User-Agent: Mutt/1.5.9i X-Virus-Scanned: by amavisd-new Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org On Wed, Jun 22, 2005 at 06:24:54PM -0400, Jeff Garzik wrote: > > Things in git-land are moving at lightning speed, and usability has > improved a lot since my post a month ago: http://lkml.org/lkml/2005/5/26/11 And here's a quick comparison with the current state of Mercurial.. > 1) installing git > > git requires bootstrapping, since you must have git installed in order > to check out git.git (git repo), and linux-2.6.git (kernel repo). I > have put together a bootstrap tarball of today's git repository. > > Download tarball from: > http://www.kernel.org/pub/linux/kernel/people/jgarzik/git-20050622.tar.bz2 > > tarball build-deps: zlib, libcurl, libcrypto (openssl) > > install tarball: unpack && make && sudo make prefix=/usr/local install > > jgarzik helper scripts, not in official git distribution: > http://www.kernel.org/pub/linux/kernel/people/jgarzik/git-new-branch > http://www.kernel.org/pub/linux/kernel/people/jgarzik/git-changes-script > > After reading the rest of this document, come back and update your copy > of git to the latest: > rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/git.git Download from: http://selenic.com/mercurial/mercurial-snapshot.tar.gz Build-deps: Python 2.3 Install: unpack && python setup.py install [--home=/usr/local] > 2) download a linux kernel tree for the very first time > > $ mkdir -p linux-2.6/.git > $ cd linux-2.6 > $ rsync -a --delete --verbose --stats --progress \ > rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git/ > \ <- word-wrapped backslash; sigh > .git/ $ mkdir linux-2.6 $ cd linux-2.6 $ hg init http://www.kernel.org/hg/ # obviously you can also browse this This downloads about 125M of data, which include the whole kernel history back to 2.4.0 and everything in Linus' git repo as well. > 3) update local kernel tree to latest 2.6.x upstream ("fast-forward merge") > > $ cd linux-2.6 > $ git-pull-script \ > rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git $ hg pull # defaults to where you originally pulled from It takes about 4M of transfer and well under a minute to pull the entire git history, starting from a base of 2.6.12-rc2. > 4) check out files from the git repository into the working directory > > $ git checkout -f $ hg update # or up or checkout or co, depending on your SCM habits > 5) check in your own modifications (e.g. do some hacking, or apply a patch) > > # go to repo > $ cd linux-2.6 > > # make some modifications > $ patch -sp1 < /tmp/my.patch > $ diffstat -p1 < /tmp/my.patch > > # NOTE: add '--add' and/or '--remove' if files were added or removed > $ git-update-cache > > # check in changes > $ git commit $ hg commit [files] # check in everything changed or just the named files 5.1) undo the last commit or pull $ hg undo > 6) List all changes in working dir, in diff format. > > $ git-diff-cache -p HEAD $ hg status # show changed files > 7) List all changesets (i.e. show each cset's description text) in local > branch of local tree, that are not present in remote tree. > > $ cd my-kernel-tree-2.6 > $ git-changes-script -L ../linux-2.6 | less $ hg history | less # How does git know what's not in the # remote tree? Psychic? > 8) List all changesets: > > $ git-whatchanged $ hg history | less > 9) apply all patches in a Berkeley mbox-format file > > First, download and add to your PATH Linus's git tools: > rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/git-tools.git > > $ cd my-kernel-tree-2.6 > $ dotest /path/to/mbox # yes, Linus has no taste in naming scripts hg doesn't do mboxes directly, but you can do: $ cat patch-list | xargs hg import > 10) don't forget to download tags from time to time. > > git-pull-script only downloads sha1-indexed object data, and the > requested remote head. This misses updates to the .git/refs/tags/ and > .git/refs/heads directories. It is advisable to update your kernel .git > directories periodically with a full rsync command, to make sure you got > everything: > > $ cd linux-2.6 > $ rsync -a --delete --verbose --stats --progress \ > rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git/ > \ <- word-wrapped backslash; sigh > .git/ Tags in mercurial are properly version controlled and come along for the ride with pulls. Also, the right thing happens with merges. > 11) list all branches, such as those found in my netdev-2.6 or > libata-dev trees. > > Download > rsync://rsync.kernel.org/pub/scm/linux/kernel/git/jgarzik/netdev-2.6.git > or > rsync://rsync.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev.git > > > $ cd netdev-2.6 > $ ls .git/refs/heads/ > > { these are the current netdev-2.6 branches } > >8139cp forcedeth master qeth smc91x we18 > >8139too-iomap for-linus natsemi r8169 smc91x-eeprom wifi > >airo hdlc ns83820 register-netdev starfire > >atmel ieee80211 orinoco remove-drivers tlan > >chelsio iff-running orinoco-hch sis900 veth > >dm9000 janitor ppp skge viro $ hg heads # Has Andrew mentioned your git forest gives him a headache? > 12) make desired branch current in working directory > > $ git checkout -f $branch $ hg update -C > 13) create a new branch, and make it current > > $ cp .git/refs/heads/master .git/refs/heads/my-new-branch-name > $ git checkout -f my-new-branch-name Since the hg repo is lightweight, this is usually done by just having different directories. Thus we don't explicitly name branches. $ mkdir new-branch $ cd new-branch $ hg init -u ../linux # makes hardlinks and does a checkout > 14) examine which branch is current > > $ ls -l .git/HEAD $ echo $PWD > 15) undo all local modifications (same as checkout): > > $ git checkout -f $ hg update -C > 16) obtain a diff between current branch, and master branch > > In most trees WITH BRANCHES, .git/refs/heads/master contains the current > 'vanilla' upstream tree, for easy diffing and merging. (in trees > without branches, 'master' simply contains your latest changes) > > $ git-diff-tree -p master HEAD $ hg diff -r -r 17) run a browsable, pullable repo server of the current repo on your local machine $ hg serve 18) push your changes to a remote server $ hg push ssh://user@host/path/ # aliases and defaults in .hgrc 19) get per-file history $ hg log | less 20) get annotated file contents $ hg annotate [file] 21) record that a file has been copied or renamed for the next commit $ hg copy 22) get online help $ hg help [command] More info at http://selenic.com/mercurial/ -- Mathematics is the supreme nostalgia of our time.