git-cvsserver(1) — Linux manual page


GIT-CVSSERVER(1)               Git Manual               GIT-CVSSERVER(1)

NAME         top

       git-cvsserver - A CVS server emulator for Git

SYNOPSIS         top


       export CVS_SERVER="git cvsserver"
       cvs -d :ext:user@server/path/repo.git co <HEAD_name>

       pserver (/etc/inetd.conf):

       cvspserver stream tcp nowait nobody /usr/bin/git-cvsserver git-cvsserver pserver


       git-cvsserver [<options>] [pserver|server] [<directory> ...]

DESCRIPTION         top

       This application is a CVS emulation layer for Git.

       It is highly functional. However, not all methods are
       implemented, and for those methods that are implemented, not all
       switches are implemented.

       Testing has been done using both the CLI CVS client, and the
       Eclipse CVS plugin. Most functionality works fine with both of
       these clients.

OPTIONS         top

       All these options obviously only make sense if enforced by the
       server side. They have been implemented to resemble the
       git-daemon(1) options as closely as possible.

       --base-path <path>
           Prepend path to requested CVSROOT

           Don’t allow recursing into subdirectories

           Don’t check for gitcvs.enabled in config. You also have to
           specify a list of allowed directories (see below) if you want
           to use this option.

       -V, --version
           Print version information and exit

       -h, -H, --help
           Print usage information and exit

           You can specify a list of allowed directories. If no
           directories are given, all are allowed. This is an additional
           restriction, gitcvs access still needs to be enabled by the
           gitcvs.enabled config option unless --export-all was given,

LIMITATIONS         top

       CVS clients cannot tag, branch or perform Git merges.

       git-cvsserver maps Git branches to CVS modules. This is very
       different from what most CVS users would expect since in CVS
       modules usually represent one or more directories.

INSTALLATION         top

        1. If you are going to offer CVS access via pserver, add a line
           in /etc/inetd.conf like

                  cvspserver stream tcp nowait nobody git-cvsserver pserver

           Note: Some inetd servers let you specify the name of the
           executable independently of the value of argv[0] (i.e. the
           name the program assumes it was executed with). In this case
           the correct line in /etc/inetd.conf looks like

                  cvspserver stream tcp nowait nobody /usr/bin/git-cvsserver git-cvsserver pserver

           Only anonymous access is provided by pserve by default. To
           commit you will have to create pserver accounts, simply add a
           gitcvs.authdb setting in the config file of the repositories
           you want the cvsserver to allow writes to, for example:

                       authdb = /etc/cvsserver/passwd

           The format of these files is username followed by the
           encrypted password, for example:


           You can use the htpasswd facility that comes with Apache to
           make these files, but Apache’s MD5 crypt method differs from
           the one used by most C library’s crypt() function, so don’t
           use the -m option.

           Alternatively you can produce the password with perl’s
           crypt() operator:

                  perl -e 'my ($user, $pass) = @ARGV; printf "%s:%s\n", $user, crypt($user, $pass)' $USER password

           Then provide your password via the pserver method, for

                  cvs -d:pserver:someuser:somepassword <at> server/path/repo.git co <HEAD_name>

           No special setup is needed for SSH access, other than having
           Git tools in the PATH. If you have clients that do not accept
           the CVS_SERVER environment variable, you can rename
           git-cvsserver to cvs.

           Note: Newer CVS versions (>= 1.12.11) also support specifying
           CVS_SERVER directly in CVSROOT like

               cvs -d ":ext;CVS_SERVER=git cvsserver:user@server/path/repo.git" co <HEAD_name>

           This has the advantage that it will be saved in your CVS/Root
           files and you don’t need to worry about always setting the
           correct environment variable. SSH users restricted to
           git-shell don’t need to override the default with CVS_SERVER
           (and shouldn’t) as git-shell understands cvs to mean
           git-cvsserver and pretends that the other end runs the real
           cvs better.

        2. For each repo that you want accessible from CVS you need to
           edit config in the repo and add the following section.

                       # optional for debugging

           Note: you need to ensure each user that is going to invoke
           git-cvsserver has write access to the log file and to the
           database (see Database Backend. If you want to offer write
           access over SSH, the users of course also need write access
           to the Git repository itself.

           You also need to ensure that each repository is "bare"
           (without a Git index file) for cvs commit to work. See

           All configuration variables can also be overridden for a
           specific method of access. Valid method names are "ext" (for
           SSH access) and "pserver". The following example
           configuration would disable pserver access while still
           allowing access over SSH.


                  [gitcvs "ext"]

        3. If you didn’t specify the CVSROOT/CVS_SERVER directly in the
           checkout command, automatically saving it in your CVS/Root
           files, then you need to set them explicitly in your
           environment. CVSROOT should be set as per normal, but the
           directory should point at the appropriate Git repo. As above,
           for SSH clients not restricted to git-shell, CVS_SERVER
           should be set to git-cvsserver.

                    export CVSROOT=:ext:user@server:/var/git/project.git
                    export CVS_SERVER="git cvsserver"

        4. For SSH clients that will make commits, make sure their
           server-side .ssh/environment files (or .bashrc, etc.,
           according to their specific shell) export appropriate values
           and GIT_COMMITTER_EMAIL. For SSH clients whose login shell is
           bash, .bashrc may be a reasonable alternative.

        5. Clients should now be able to check out the project. Use the
           CVS module name to indicate what Git head you want to check
           out. This also sets the name of your newly checked-out
           directory, unless you tell it otherwise with -d <dir_name>.
           For example, this checks out master branch to the
           project-master directory:

                    cvs co -d project-master master


       git-cvsserver uses one database per Git head (i.e. CVS module) to
       store information about the repository to maintain consistent CVS
       revision numbers. The database needs to be updated (i.e. written
       to) after every commit.

       If the commit is done directly by using git (as opposed to using
       git-cvsserver) the update will need to happen on the next
       repository access by git-cvsserver, independent of access method
       and requested operation.

       That means that even if you offer only read access (e.g. by using
       the pserver method), git-cvsserver should have write access to
       the database to work reliably (otherwise you need to make sure
       that the database is up to date any time git-cvsserver is

       By default it uses SQLite databases in the Git directory, named
       gitcvs.<module_name>.sqlite. Note that the SQLite backend creates
       temporary files in the same directory as the database file on
       write so it might not be enough to grant the users using
       git-cvsserver write access to the database file without granting
       them write access to the directory, too.

       The database cannot be reliably regenerated in a consistent form
       after the branch it is tracking has changed. Example: For merged
       branches, git-cvsserver only tracks one branch of development,
       and after a git merge an incrementally updated database may track
       a different branch than a database regenerated from scratch,
       causing inconsistent CVS revision numbers. git-cvsserver has no
       way of knowing which branch it would have picked if it had been
       run incrementally pre-merge. So if you have to fully or partially
       (from old backup) regenerate the database, you should be
       suspicious of pre-existing CVS sandboxes.

       You can configure the database backend with the following
       configuration variables:

   Configuring database backend
       git-cvsserver uses the Perl DBI module. Please also read its
       documentation if changing these variables, especially about

           Database name. The exact meaning depends on the selected
           database driver, for SQLite this is a filename. Supports
           variable substitution (see below). May not contain semicolons
           (;). Default: %Ggitcvs.%m.sqlite

           Used DBI driver. You can specify any available driver for
           this here, but it might not work. cvsserver is tested with
           DBD::SQLite, reported to work with DBD::Pg, and reported not
           to work with DBD::mysql. Please regard this as an
           experimental feature. May not contain colons (:). Default:

           Database user. Only useful if setting dbDriver, since SQLite
           has no concept of database users. Supports variable
           substitution (see below).

           Database password. Only useful if setting dbDriver, since
           SQLite has no concept of database passwords.

           Database table name prefix. Supports variable substitution
           (see below). Any non-alphabetic characters will be replaced
           with underscores.

       All variables can also be set per access method, see above.

       Variable substitution
           In dbDriver and dbUser you can use the following variables:

               Git directory name

               Git directory name, where all characters except for
               alphanumeric ones, ., and - are replaced with _ (this
               should make it easier to use the directory name in a
               filename if wanted)

               CVS module/Git head name

               access method (one of "ext" or "pserver")

               Name of the user running git-cvsserver. If no name can be
               determined, the numeric uid is used.

ENVIRONMENT         top

       These variables obviate the need for command-line options in some
       circumstances, allowing easier restricted usage through

       GIT_CVSSERVER_BASE_PATH takes the place of the argument to

       GIT_CVSSERVER_ROOT specifies a single-directory whitelist. The
       repository must still be configured to allow access through
       git-cvsserver, as described above.

       When these environment variables are set, the corresponding
       command-line arguments may not be used.


       To get a checkout with the Eclipse CVS client:

        1. Select "Create a new project → From CVS checkout"

        2. Create a new location. See the notes below for details on how
           to choose the right protocol.

        3. Browse the modules available. It will give you a list of the
           heads in the repository. You will not be able to browse the
           tree from there. Only the heads.

        4. Pick HEAD when it asks what branch/tag to check out. Untick
           the "launch commit wizard" to avoid committing the .project

       Protocol notes: If you are using anonymous access via pserver,
       just select that. Those using SSH access should choose the ext
       protocol, and configure ext access on the
       Preferences→Team→CVS→ExtConnection pane. Set CVS_SERVER to "git
       cvsserver". Note that password support is not good when using
       ext, you will definitely want to have SSH keys setup.

       Alternatively, you can just use the non-standard extssh protocol
       that Eclipse offer. In that case CVS_SERVER is ignored, and you
       will have to replace the cvs utility on the server with
       git-cvsserver or manipulate your .bashrc so that calling cvs
       effectively calls git-cvsserver.


       •   CVS 1.12.9 on Debian

       •   CVS 1.11.17 on MacOSX (from Fink package)

       •   Eclipse 3.0, 3.1.2 on MacOSX (see Eclipse CVS Client Notes)

       •   TortoiseCVS


       All the operations required for normal use are supported,
       including checkout, diff, status, update, log, add, remove,

       Most CVS command arguments that read CVS tags or revision numbers
       (typically -r) work, and also support any git refspec (tag,
       branch, commit ID, etc). However, CVS revision numbers for
       non-default branches are not well emulated, and cvs log does not
       show tags or branches at all. (Non-main-branch CVS revision
       numbers superficially resemble CVS revision numbers, but they
       actually encode a git commit ID directly, rather than represent
       the number of revisions since the branch point.)

       Note that there are two ways to checkout a particular branch. As
       described elsewhere on this page, the "module" parameter of cvs
       checkout is interpreted as a branch name, and it becomes the main
       branch. It remains the main branch for a given sandbox even if
       you temporarily make another branch sticky with cvs update -r.
       Alternatively, the -r argument can indicate some other branch to
       actually checkout, even though the module is still the "main"
       branch. Tradeoffs (as currently implemented): Each new "module"
       creates a new database on disk with a history for the given
       module, and after the database is created, operations against
       that main branch are fast. Or alternatively, -r doesn’t take any
       extra disk space, but may be significantly slower for many
       operations, like cvs update.

       If you want to refer to a git refspec that has characters that
       are not allowed by CVS, you have two options. First, it may just
       work to supply the git refspec directly to the appropriate CVS -r
       argument; some CVS clients don’t seem to do much sanity checking
       of the argument. Second, if that fails, you can use a special
       character escape mechanism that only uses characters that are
       valid in CVS tags. A sequence of 4 or 5 characters of the form
       (underscore ("_"), dash ("-"), one or two characters, and dash
       ("-")) can encode various characters based on the one or two
       letters: "s" for slash ("/"), "p" for period ("."), "u" for
       underscore ("_"), or two hexadecimal digits for any byte value at
       all (typically an ASCII number, or perhaps a part of a UTF-8
       encoded character).

       Legacy monitoring operations are not supported (edit, watch and
       related). Exports and tagging (tags and branches) are not
       supported at this stage.

   CRLF Line Ending Conversions
       By default the server leaves the -k mode blank for all files,
       which causes the CVS client to treat them as a text files,
       subject to end-of-line conversion on some platforms.

       You can make the server use the end-of-line conversion attributes
       to set the -k modes for files by setting the gitcvs.usecrlfattr
       config variable. See gitattributes(5) for more information about
       end-of-line conversion.

       Alternatively, if gitcvs.usecrlfattr config is not enabled or the
       attributes do not allow automatic detection for a filename, then
       the server uses the gitcvs.allBinary config for the default
       setting. If gitcvs.allBinary is set, then file not otherwise
       specified will default to -kb mode. Otherwise the -k mode is left
       blank. But if gitcvs.allBinary is set to "guess", then the
       correct -k mode will be guessed based on the contents of the

       For best consistency with cvs, it is probably best to override
       the defaults by setting gitcvs.usecrlfattr to true, and
       gitcvs.allBinary to "guess".

DEPENDENCIES         top

       git-cvsserver depends on DBD::SQLite.

GIT         top

       Part of the git(1) suite

COLOPHON         top

       This page is part of the git (Git distributed version control
       system) project.  Information about the project can be found at
       ⟨⟩.  If you have a bug report for this manual
       page, see ⟨⟩.  This page was obtained
       from the project's upstream Git repository
       ⟨⟩ on 2021-08-27.  (At that time,
       the date of the most recent commit that was found in the
       repository was 2021-08-24.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to

Git         08/27/2021               GIT-CVSSERVER(1)

Pages that refer to this page: git(1)git-config(1)git-cvsimport(1)git-shell(1)gitcvs-migration(7)