GITCVS-MIGRATION(7)                                        GITCVS-MIGRATION(7)



NAME
       gitcvs-migration - git for CVS users

SYNOPSIS
       git cvsimport *


DESCRIPTION
       Git differs from CVS in that every working tree contains a repository
       with a full copy of the project history, and no repository is
       inherently more important than any other. However, you can emulate the
       CVS model by designating a single shared repository which people can
       synchronize with; this document explains how to do that.


       Some basic familiarity with git is required. Having gone through
       gittutorial(7) and gitglossary(7) should be sufficient.


DEVELOPING AGAINST A SHARED REPOSITORY
       Suppose a shared repository is set up in /pub/repo.git on the host
       foo.com. Then as an individual committer you can clone the shared
       repository over ssh with:

       $ git clone foo.com:/pub/repo.git/ my-project
       $ cd my-project





       and hack away. The equivalent of cvs update is

       $ git pull origin





       which merges in any work that others might have done since the clone
       operation. If there are uncommitted changes in your working tree,
       commit them first before running git pull.


              Note

              The pull command knows where to get updates from because of
              certain configuration variables that were set by the first git
              clone command; see git config -l and the git-config(1) man page
              for details.



       You can update the shared repository with your changes by first
       committing your changes, and then using the git push command:

       $ git push origin master





       to "push" those commits to the shared repository. If someone else has
       updated the repository more recently, git push, like cvs commit, will
       complain, in which case you must pull any changes before attempting the
       push again.


       In the git push command above we specify the name of the remote branch
       to update (master). If we leave that out, git push tries to update any
       branches in the remote repository that have the same name as a branch
       in the local repository. So the last push can be done with either of:

       $ git push origin
       $ git push foo.com:/pub/project.git/





       as long as the shared repository does not have any branches other than
       master.


SETTING UP A SHARED REPOSITORY
       We assume you have already created a git repository for your project,
       possibly created from scratch or from a tarball (see gittutorial(7)),
       or imported from an already existing CVS repository (see the next
       section).


       Assume your existing repo is at /home/alice/myproject. Create a new
       "bare" repository (a repository without a working tree) and fetch your
       project into it:

       $ mkdir /pub/my-repo.git
       $ cd /pub/my-repo.git
       $ git --bare init --shared
       $ git --bare fetch /home/alice/myproject master:master





       Next, give every team member read/write access to this repository. One
       easy way to do this is to give all the team members ssh access to the
       machine where the repository is hosted. If you don&#8217;t want to give
       them a full shell on the machine, there is a restricted shell which
       only allows users to do git pushes and pulls; see git-shell(1).


       Put all the committers in the same group, and make the repository
       writable by that group:

       $ chgrp -R $group /pub/my-repo.git





       Make sure committers have a umask of at most 027, so that the
       directories they create are writable and searchable by other group
       members.


IMPORTING A CVS ARCHIVE
       First, install version 2.1 or higher of cvsps from
       http://www.cobite.com/cvsps/: http://www.cobite.com/cvsps/ and make
       sure it is in your path. Then cd to a checked out CVS working directory
       of the project you are interested in and run git-cvsimport(1):

       $ git cvsimport -C <destination> <module>





       This puts a git archive of the named CVS module in the directory
       <destination>, which will be created if necessary.


       The import checks out from CVS every revision of every file. Reportedly
       cvsimport can average some twenty revisions per second, so for a
       medium-sized project this should not take more than a couple of
       minutes. Larger projects or remote repositories may take longer.


       The main trunk is stored in the git branch named origin, and additional
       CVS branches are stored in git branches with the same names. The most
       recent version of the main trunk is also left checked out on the master
       branch, so you can start adding your own changes right away.


       The import is incremental, so if you call it again next month it will
       fetch any CVS updates that have been made in the meantime. For this to
       work, you must not modify the imported branches; instead, create new
       branches for your own changes, and merge in the imported branches as
       necessary.


       If you want a shared repository, you will need to make a bare clone of
       the imported directory, as described above. Then treat the imported
       directory as another development clone for purposes of merging
       incremental imports.


ADVANCED SHARED REPOSITORY MANAGEMENT
       Git allows you to specify scripts called "hooks" to be run at certain
       points. You can use these, for example, to send all commits to the
       shared repository to a mailing list. See githooks(5).


       You can enforce finer grained permissions using update hooks. See
       Controlling access to branches using update hooks: howto/update-hook-
       example.txt.


PROVIDING CVS ACCESS TO A GIT REPOSITORY
       It is also possible to provide true CVS access to a git repository, so
       that developers can still use CVS; see git-cvsserver(1) for details.


ALTERNATIVE DEVELOPMENT MODELS
       CVS users are accustomed to giving a group of developers commit access
       to a common repository. As we&#8217;ve seen, this is also possible with
       git. However, the distributed nature of git allows other development
       models, and you may want to first consider whether one of them might be
       a better fit for your project.


       For example, you can choose a single person to maintain the
       project&#8217;s primary public repository. Other developers then clone
       this repository and each work in their own clone. When they have a
       series of changes that they&#8217;re happy with, they ask the
       maintainer to pull from the branch containing the changes. The
       maintainer reviews their changes and pulls them into the primary
       repository, which other developers pull from as necessary to stay
       coordinated. The Linux kernel and other projects use variants of this
       model.


       With a small group, developers may just pull changes from each
       other&#8217;s repositories without the need for a central maintainer.


SEE ALSO
       gittutorial(7), gittutorial-2(7), gitcore-tutorial(7), gitglossary(7),
       Everyday Git: everyday.html, The Git User&#8217;s Manual: user-
       manual.html


GIT
       Part of the git(1) suite.




                                                           GITCVS-MIGRATION(7)
