# gitcvs-migration

## 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’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



               **Note**
    
               These instructions use the **git-cvsimport** script which ships
               with git, but other importers may provide better results. See
               the note in git-cvsimport(1) for other options.
    
           First, install version 2.1 or higher of cvsps from
           **https://github.com/andreyvit/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 rungit-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******[1].


## 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’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’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’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’s repositories without the need for a central maintainer.
    


## GIT



           Part of the git(1) suite
    


## NOTES



            1. Controlling access to branches using update hooks
               file:///home/mtk/share/doc/git-doc/howto/update-hook-example.html
    
            2. The Git User’s Manual
               file:///home/mtk/share/doc/git-doc/user-manual.html
    


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