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  12 <title>cvs2bzr Documentation</title>
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  17
  18 <h1>cvs2bzr</h1>
  19
  20 <h2>Index</h2>
  21
  22 <ul>
  23
  24   <li><a href="#intro">Introduction</a></li>
  25
  26   <li><a href="#reqs">Requirements</a></li>
  27
  28   <li><a href="#status">Development status</a></li>
  29
  30   <li><a href="#docs">Documentation</a></li>
  31
  32   <li><a href="#usage">Usage</a></li>
  33
  34 </ul>
  35
  36 <hr />
  37
  38 <h2><a name="intro">Introduction</a></h2>
  39
  40 <p>cvs2svn/cvs2bzr is a tool that can be used to migrate CVS
  41 repositories to newer version control tools, including <a
  42     href="http://bazaar-vcs.org/">Bazaar</a>.  Bazaar is an adaptive
  43 version control system that supports both centralised and distributed
  44 version control. It is most famous for being used for Ubuntu and
  45 MySQL development. The program used to convert to Bazaar, called
  46 cvs2bzr, is distributed as part of the cvs2svn project.</p>
  47
  48 <p><strong>If you are reading this documentation on the <a
  49 href="http://cvs2svn.tigris.org">cvs2svn website</a>, then please be
  50 aware that it describes the current trunk version of cvs2svn, which
  51 may be different than the most recent released version.  Please refer
  52 to the documentation that was included with your version of cvs2svn.
  53 </strong></p>
  54
  55 <p>Conversion to Bazaar was added in release 2.3 of cvs2svn and may have
  56 improved significantly since then.  Please make sure you are using an
  57 up-to-date version of cvs2svn--perhaps even the development trunk
  58 version.</p>
  59
  60
  61 <h2><a name="reqs">Requirements</a></h2>
  62
  63 <p>cvs2bzr requires the following:</p>
  64
  65 <ul>
  66
  67   <li>Direct (filesystem) access to a copy of the CVS repository that
  68     you want to convert.  cvs2bzr parses the files in the CVS
  69     repository directly, so it is not enough to have remote CVS
  70     access.  See the <a href="faq.html#repoaccess">FAQ</a> for more
  71     information and a possible workaround.</li>
  72
  73   <li>Python 2, version 2.4 or later.  See <a
  74     href="http://www.python.org/">http://www.python.org/</a>.
  75     (cvs2bzr does <strong>not</strong> work with Python 3.x.)</li>
  76
  77   <li>If you use the <tt>--use-rcs</tt> option, then RCS's `co'
  78     program is required.  The RCS home page is
  79     <a href="http://www.cs.purdue.edu/homes/trinkle/RCS/"
  80             >http://www.cs.purdue.edu/homes/trinkle/RCS/</a>.
  81     See the <a href="cvs2svn.html#use-rcs"><tt>--use-rcs</tt> flag</a> for more
  82     details.</li>
  83
  84   <li>If you use the <tt>--use-cvs</tt> option, then the `cvs' command
  85     is required.  The CVS home page is
  86     <a href="http://ccvs.cvshome.org/">http://ccvs.cvshome.org/</a>.
  87     See the <a href="cvs2svn.html#use-cvs"><tt>--use-cvs</tt> flag</a> for more
  88     details.</li>
  89
  90   <li>GNU sort, which is part of the coreutils package, see <a
  91     href="http://www.gnu.org/software/coreutils/"
  92          >http://www.gnu.org/software/coreutils/</a>.  Binaries for
  93     Win32 can be found at <a href="http://unxutils.sourceforge.net/"
  94                                   >http://unxutils.sourceforge.net/</a>.
  95     Windows <tt>sort.exe</tt> is <b>not</b> adequate.</li>
  96
  97   <li> Bazaar version 1.13 or later.</li>
  98
  99   <li> The bzr-fastimport plugin version 0.9 or later.</li>
 100
 101 </ul>
 102
 103
 104 <h2><a name="status">Development status</a></h2>
 105
 106 <p>Most of the work of converting a repository from CVS to a more
 107 modern version control system is inferring the most likely history
 108 given the incomplete information that CVS records.  cvs2svn has a long
 109 history of making sense of even the most convoluted CVS repositories,
 110 and cvs2bzr uses this same machinery.  Therefore, cvs2bzr inherits the
 111 robustness and many of the <a href="features.html">features of
 112 cvs2svn</a>.  cvs2svn can convert just about every CVS repository we
 113 have ever seen, and includes a plethora of options for customizing
 114 your conversion.</p>
 115
 116 <p>The output of cvs2bzr is a "fastimport" dump file that can be
 117 imported into Bazaar using the <a
 118     href="https://launchpad.net/bzr-fastimport/">bzr-fastimport</a>
 119 plugin.</p>
 120
 121 <p>Although cvs2bzr is considerably newer than cvs2svn, and much less
 122 well tested, it is believed that cvs2bzr can (cautiously) be used for
 123 production conversions. If you use cvs2bzr, please let us know how it
 124 worked for you!</p>
 125
 126
 127 <h2><a name="limitations">cvs2bzr limitations</a></h2>
 128
 129 <p>cvs2bzr still has many limitations compared to cvs2svn.  The main
 130 cvs2svn developer has limited Bazaar experience and very limited time, so
 131 <strong>help would be much appreciated!</strong> Some of these missing
 132 features would be pretty easy to program, and I'd be happy to help you
 133 get started.</p>
 134
 135 <ul>
 136
 137   <li>The cvs2bzr documentation is still rather thin.  See <a
 138     href="#docs">below</a> for more references.</li>
 139
 140   <li>CVS allows a branch to be created from arbitrary combinations of
 141     source revisions and/or source branches.  cvs2bzr tries to create
 142     a branch from a single source, but if it can't figure out how to,
 143     it creates the branch using "merge" from multiple sources.  In
 144     pathological situations, the number of merge sources for a branch
 145     can be arbitrarily large.</li>
 146
 147   <li>There are no checks that CVS branch and tag names are legal
 148     names in Bazaar. This is unlikely to be a problem because Bazaar
 149     uses paths for branch names similar to CVS and Subversion. Tag
 150     naming in Bazaar is also more flexible than in git, say.</li>
 151
 152   <li>Only single projects can be converted at a time.  Given the way
 153     Bazaar is typically used, I don't think that this is a significant
 154     limitation.</li>
 155
 156   <li>cvs2bzr is not especially fast.  Among other things, it still
 157     uses RCS or CVS to extract the contents of the CVS revisions.
 158     Implementing the <tt>--internal-co</tt> option for cvs2bzr (using
 159     code that already exists in cvs2svn) might improve the conversion
 160     speed considerably.</li>
 161
 162   <li>The cvs2svn test suite does not include meaningful tests of
 163     Bazaar output.</li>
 164
 165   <li>cvs2bzr makes no attempt to convert <tt>.cvsignore</tt> files
 166     into <tt>.bzrignore</tt> files.</li>
 167
 168   <li>cvs2bzr, like cvs2svn, does not support incremental conversion
 169     (i.e., tracking a live CVS repository).  However, this <a
 170     href="http://www.oak.homeunix.org/~marcel/blog/2009/06/03/tracking-cvs-with-git-using-cvs2git">possible
 171     workaround</a> for using cvs2git along those lines might provide
 172     some assistance for anyone wanting to try doing that using
 173     cvs2bzr.</li>
 174
 175 </ul>
 176
 177
 178 <h2><a name="docs">Documentation</a></h2>
 179
 180 <p>There is some documentation specific to cvs2bzr, and much of the
 181 cvs2svn documentation also applies fairly straightforwardly to
 182 cvs2bzr.  See the following sources:</p>
 183
 184 <ul>
 185
 186   <li>This document.</li>
 187
 188   <li>The cvs2bzr man page and the output of <tt>cvs2bzr
 189     --help</tt>.</li>
 190
 191   <li><a href="cvs2svn.html#intro">The cvs2svn documentation</a> and
 192     <a href="faq.html">the cvs2svn FAQ</a>, which contain much general
 193     discussion and describe many features that can also be used for
 194     cvs2bzr.</li>
 195
 196   <li><tt>cvs2bzr-example.options</tt> in the cvs2svn source tree,
 197     which is an example of an options file that can be used to
 198     configure a cvs2bzr conversion.  The file is extensively
 199     documented.</li>
 200
 201   <li>The cvs2svn mailing lists, IRC channel, etc., as described in <a
 202     href="faq.html#gettinghelp">the cvs2svn FAQ</a>.</li>
 203
 204   <li>The <a href="http://doc.bazaar-vcs.org/migration/en/data-migration/">
 205     Bazaar Data Migration Guide</a>.</li>
 206
 207 </ul>
 208
 209
 210 <h2><a name="usage">Usage</a></h2>
 211
 212 <p>This section outlines the steps needed to convert a CVS repository
 213 to Bazaar using cvs2bzr.</p>
 214
 215 <ol>
 216
 217   <li>Be sure that you have the <a href="#reqs">requirements</a>,
 218     including either RCS or CVS (used to read revision contents from
 219     the CVS repository).</li>
 220
 221   <li>Obtain a copy of cvs2svn/cvs2bzr version 2.3 or newer.  It is
 222     recommended that you use the most recent version available, or
 223     even the development version.
 224
 225     <ul>
 226
 227       <li>To install cvs2svn from a <a
 228         href="http://cvs2svn.tigris.org/servlets/ProjectDocumentList">tarball</a>,
 229         simply unpack the tarball into a directory on your conversion
 230         computer (cvs2bzr can be run directly from this
 231         directory).</li>
 232
 233       <li>
 234
 235         <p>To check out the current trunk version of cvs2svn, make
 236           sure that you have Subversion installed and then run:</p>
 237
 238 <pre>
 239 svn co --username=guest http://cvs2svn.tigris.org/svn/cvs2svn/trunk cvs2svn-trunk
 240 # The password is empty; i.e., just press return.
 241 cd cvs2svn-trunk
 242 make man # If you want to create manpages for the main programs
 243 make check # ...optional
 244 </pre>
 245
 246         <p>Please note that the test suite includes tests that are
 247           marked "XFAIL" (expected failure); these are known and are
 248           not considered serious problems.</p>
 249
 250       </li>
 251
 252     </ul>
 253
 254   </li>
 255
 256   <li>
 257
 258     Configure cvs2bzr for your conversion.  This can be done via
 259     command-line options or via an options file:
 260
 261     <ul>
 262
 263       <li>The command-line options for running cvs2bzr are documented
 264         in the cvs2bzr man page and in the output of <tt>cvs2bzr
 265         --help</tt>.</li>
 266
 267       <li>
 268
 269         <p>The more flexible <a
 270           href="cvs2svn.html#cmd-vs-options">options-file method</a>
 271           requires you to create an options file, then start cvs2bzr
 272           with</p>
 273
 274 <pre>
 275 cvs2bzr --options=OPTIONS-FILE
 276 </pre>
 277
 278         <p>Use <tt>cvs2bzr-example.options</tt> in the cvs2svn source
 279           tree as your starting point; the file contains lots of
 280           documentation.</p>
 281
 282       </li>
 283
 284     </ul>
 285
 286   </li>
 287
 288   <li>
 289
 290     <p>Run cvs2bzr.  This creates an output file in <a
 291         href="http://www.kernel.org/pub/software/scm/git/docs/git-fast-import.html">fast-import</a>
 292     format.  The name of this file is specified by
 293     your options file or a command-line argument.  In the example,
 294     the file is named <tt>cvs2svn-tmp/dumpfile.fi</tt>.</p>
 295
 296   </li>
 297
 298   <li>
 299
 300     <p>Load the dump file using bzr fast-import:</p>
 301
 302 <pre>
 303 bzr fast-import cvs2svn-tmp/dumpfile.fi project.bzr
 304 </pre>
 305
 306   </li>
 307
 308 </ol>
 309
 310 <p>Feedback would be much appreciated, including reports of success
 311   using cvs2bzr.  Please send comments, bug reports, and patches to
 312   the <a
 313   href="http://cvs2svn.tigris.org/servlets/ProjectMailingListList">cvs2svn
 314   mailing lists</a>.</p>
 315
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