git2svn

   1 #!/usr/bin/perl
   2 #
   3 #    git2svn, converts a git branch to a svn ditto
   4 #    Copyright (C) 2008  Love Hörnquist Åstrand
   5 #
   6 #    This program is free software: you can redistribute it and/or modify
   7 #    it under the terms of the GNU General Public License as published by
   8 #    the Free Software Foundation, either version 3 of the License, or
   9 #    (at your option) any later version.
  10 #
  11 #    This program is distributed in the hope that it will be useful,
  12 #    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 #    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 #    GNU General Public License for more details.
  15 #
  16 #    You should have received a copy of the GNU General Public License
  17 #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 use strict;
  20 use POSIX qw(strftime);
  21 use Getopt::Long qw/:config gnu_getopt no_ignore_case auto_abbrev/;
  22 use Pod::Usage;
  23
  24 my $IN;
  25 my $OUT;
  26
  27 my ($help, $verbose);
  28
  29 # svn
  30 my $svntree = "repro";
  31 my $basedir = "trunk";
  32 my $revision = 1;
  33
  34 # git
  35 my $branch = "master";
  36 my $gittree;
  37 my $syncname;
  38 my $masterrev;
  39 my $fexport;
  40
  41
  42 my %blob;
  43 my %paths;
  44
  45 sub read_data
  46 {
  47     my ($IN, $next, $length, $data, $l) = (shift, shift);
  48     unless($next =~ m/^data (\d+)/) { die "missing data: $next" ; }
  49     $length = $1;
  50
  51     $l = read(IN, $data, $length);
  52     unless ($l == $length) { die "failed to read data $l != $length"; }
  53     $data = "" if ($length == 0);
  54     return $data;
  55 }
  56
  57 sub prop
  58 {
  59     my ($key, $value) = (shift, shift);
  60     "K " . length($key) . "\n$key\nV " . length($value) . "\n$value\n";
  61 }
  62
  63 sub parse_svn_tree
  64 {
  65     my $url = shift;
  66     my ($SVN, $type, $name);
  67
  68     open(SVN, "svn ls -R $url|") or die "failed to open svn ls -R $url";
  69     while (<SVN>) {
  70         if (m@/(.*)/$@) {
  71             $type = 1;
  72             $name = "$basedir/$1";
  73         } else {
  74             $type = 2;
  75             $name = "$basedir/$_";
  76         }
  77         $paths{$name} = $type;
  78     }
  79     close SVN;
  80
  81     open(SVN, "svn info $url|") or die "failed to open svn info $url";
  82     while (<SVN>) {
  83         if (/^Revision: (\d+)/) {
  84             $revision = $1 + 1;
  85             last;
  86         }
  87     }
  88     close SVN;
  89 }
  90
  91 sub parse_git_tree
  92 {
  93     $masterrev= `cat ${gittree}/.git/refs/heads/${branch}`;
  94     chomp($masterrev);
  95
  96     die "No head found for ${branch}" if ($masterrev eq "");
  97
  98     my $syncpoint="${gittree}/.git/refs/tags/${syncname}";
  99
 100     if (-f ${syncpoint}) {
 101         my $oldmasterrev=`cat ${syncpoint}`;
 102         chomp($oldmasterrev);
 103
 104         if (${oldmasterrev} eq ${masterrev}) {
 105             print STDERR "nothing to sync\n" if ($verbose);
 106             exit 0;
 107         }
 108
 109         die "no $svntree, but incremental (have synctag) ?\n".
 110             "(\"cd $gittree && git tag -d $syncname\" to remove)"
 111             unless ( -d $svntree);
 112
 113         $fexport = "$oldmasterrev..$masterrev";
 114     } else {
 115         $fexport="${masterrev}";
 116
 117         system("svnadmin create ./$svntree") unless (-d $svntree);
 118     }
 119 }
 120
 121
 122 sub checkdirs
 123 {
 124     my $path = shift;
 125     my $base = "";
 126
 127     # pick first dir, create, take next dir, continue until we reached basename
 128     while ($path =~ m@^([^/]+)/(.*)$@) {
 129         my $first = $base . $1;
 130         $path = $2;
 131         $base = $first . "/";
 132         next if ($paths{$first});
 133
 134         $paths{$first} = 1;
 135
 136         printf OUT "Node-path: $first\n";
 137         printf OUT "Node-kind: dir\n";
 138         printf OUT "Node-action: add\n";
 139         printf OUT "Prop-content-length: 0\n";
 140         printf OUT "Content-length: 0\n";
 141         printf OUT "\n";
 142     }
 143 }
 144
 145 sub next_line
 146 {
 147     my $IN = shift;
 148     my $next = <IN>;
 149     chomp $next;
 150     return $next;
 151 }
 152
 153 $|= 1;
 154
 155 my $result;
 156 $result = GetOptions ("git-branch=s" => \$branch,
 157                       "svn-prefix=s" => \$basedir,
 158                       "verbose+" => \$verbose,
 159                       "help" => \$help) or pod2usage(2);
 160
 161 pod2usage(0) if ($help);
 162
 163 die "to few arguments" if ($#ARGV < 1);
 164
 165 mkdir ".data" unless (-d ".data");
 166
 167 $syncname = "git2svn-syncpoint-${branch}";
 168
 169 my $gitdump = ".data/git.dump-${branch}";
 170 my $svndump = ".data/svn.dump-${branch}";
 171 my $log = ".data/log-${branch}";
 172
 173 $gittree = $ARGV[0];
 174 $svntree = $ARGV[1];
 175
 176 parse_git_tree($gittree);
 177
 178 my $cwd = `pwd`;
 179 chomp($cwd);
 180 parse_svn_tree("file://" . $cwd ."/". $svntree);
 181
 182 system(">$log");
 183
 184 print STDERR "git fast-export $branch ($fexport)\n" if ($verbose);
 185
 186 system("(cd $gittree && git fast-export $fexport) > $gitdump 2>$log") == 0 or
 187     die "git fast-export: $!";
 188
 189 open IN, "$gitdump" or
 190     die "failed to open $gitdump";
 191
 192 open OUT, ">$svndump" or
 193     die "failed to open $svndump";
 194
 195 print STDERR "creating svn dump from revision $revision...\n" if ($verbose);
 196
 197 print OUT "SVN-fs-dump-format-version: 3\n";
 198
 199 my $next = next_line();
 200 COMMAND: while (!eof(IN)) {
 201     my $mark = undef;
 202     if ($next eq "") {
 203         $next = next_line($IN);
 204         next COMMAND;
 205     } elsif ($next =~ /^commit (.*)/) {
 206
 207         my %commit;
 208
 209         $next = next_line($IN);
 210         if ($next =~ m/mark (.*)/) {
 211             $mark = $1;
 212             $next = next_line($IN);
 213         }
 214         if ($next =~ m/author (.*)/) {
 215             $commit{author} = $1;
 216             $next = next_line($IN);
 217         }
 218         unless ($next =~ m/committer (.+) <([^>]+)> (\d+) \+(\d+)$/) {
 219             die "missing comitter"
 220         }
 221
 222         $commit{CommitterName} = $1;
 223         $commit{CommitterEmail} = $2;
 224         $commit{CommitterWhen} = $3;
 225         $commit{CommitterTZ} = $4;
 226
 227         $next = next_line($IN);
 228         my $log = read_data($IN, $next);
 229
 230         $next = next_line($IN);
 231         if ($next =~ m/from (.*)/) {
 232             $next = next_line($IN);
 233         }
 234         if ($next =~ m/merge (.*)/) {
 235             $next = next_line($IN);
 236         }
 237
 238         my $date =
 239             strftime("%Y-%m-%dT%H:%M:%S.000000Z",
 240                      gmtime($commit{CommitterWhen}));
 241
 242         my $author = "(no author)";
 243         if ($commit{CommitterEmail} =~ m/([^@]+)/) {
 244             $author = $1;
 245         }
 246         $author = "git2svn-dump" if ($author eq "(no author)");
 247
 248         my $props = "";
 249         $props .= prop("svn:author", $author);
 250         $props .= prop("svn:log", $log);
 251         $props .= prop("svn:date", $date);
 252         $props .= "PROPS-END";
 253
 254         # push out svn info
 255
 256         printf OUT "Revision-number: $revision\n"; $revision++;
 257         printf OUT "Prop-content-length: ". length($props) . "\n";
 258         printf OUT "Content-length: " . length($props) . "\n";
 259         printf OUT "\n";
 260         print OUT "$props\n";
 261
 262         while (1) {
 263             if ($next =~ m/M (\d+) (\S+) (.*)$/) {
 264                 my ($mode, $dataref, $path) = (oct $1, $2, $3);
 265                 my $content;
 266                 if ($dataref eq "inline") {
 267                     $next = next_line($IN);
 268                     $content = read_data($IN, $next);
 269                 } else {
 270                     die "Revision missing content ref $dataref"
 271                         unless(defined $blob{$dataref});
 272
 273                     $content = $blob{$dataref};
 274                     # here we really want to delete $blob{$dataref},
 275                     # but it might be referenced in the future. To
 276                     # avoid keepig everything in memory for larger
 277                     # repositories this must be written out to disk
 278                     # and removed when done.
 279                 }
 280
 281                 checkdirs("$basedir/$path");
 282
 283                 my $action = "add";
 284
 285                 if ($paths{$path}) {
 286                     die "file was a dir" if ($paths{$path} != 2);
 287                     $action = "change";
 288                 } else {
 289                     $paths{$path} = 2;
 290                 }
 291
 292
 293                 my $type = $mode & 0777000;
 294                 my $kind = "";
 295                 $kind = "file" if ($type == 0100000);
 296                 $kind = "symlink" if ($type == 0120000);
 297                 die "$type unknown" if ($kind eq "");
 298
 299                 $props = "";
 300                 $props .= prop("svn:executable", "on") if ($mode & 0111);
 301                 $props .= "PROPS-END" if ($props ne "");
 302
 303                 my $plen = length($props);
 304                 my $clen = length($content);
 305
 306                 printf OUT "Node-path: $basedir/$path\n";
 307                 printf OUT "Node-kind: $kind\n";
 308                 printf OUT "Node-action: $action\n";
 309                 printf OUT "Text-content-length: $clen\n";
 310                 printf OUT "Content-length: " . ($clen + $plen) . "\n";
 311                 printf OUT "Prop-content-length: $plen\n" if ($plen);
 312                 printf OUT "\n";
 313
 314                 print OUT "$props\n" if ($plen);
 315
 316                 print OUT $content;
 317                 printf OUT "\n";
 318             } elsif ($next =~ m/D (.*)/) {
 319                 my $path = $1;
 320
 321                 die "deleting non existing object" unless ($paths{$path});
 322
 323                 delete $paths{$path};
 324
 325                 printf OUT "Node-path: $basedir/$path\n";
 326                 printf OUT "Node-action: delete\n";
 327                 printf OUT "\n";
 328
 329             } elsif ($next =~ m/^C (.*)/) {
 330                 die "file copy ?";
 331             } elsif ($next =~ m/^R (.*)/) {
 332                 die "file rename ?";
 333             } elsif ($next =~ m/^filedeleteall$/) {
 334                 die "file delete all ?";
 335             } else {
 336                 next COMMAND;
 337             }
 338             $next = next_line($IN);
 339         }
 340
 341     } elsif ($next =~ /^tag .*/) {
 342     } elsif ($next =~ /^reset .*/) {
 343     } elsif ($next =~ /^blob/) {
 344         $next = next_line($IN);
 345         if ($next =~ m/mark (.*)/) {
 346             $mark = $1;
 347             $next = next_line($IN);
 348         }
 349         my $data = read_data($IN, $next);
 350         $blob{$mark} = $data if (defined $mark);
 351     } elsif ($next =~ /^checkpoint .*/) {
 352     } elsif ($next =~ /^progress (.*)/) {
 353         print STDERR "progress: $1\n" if ($verbose);
 354     } else {
 355         die "unknown command $next";
 356     }
 357     $next = next_line($IN);
 358 }
 359
 360 close IN;
 361 close OUT;
 362
 363 print STDERR "(re-)setting sync-tag to new master\n" if ($verbose);
 364
 365 system("cd $gittree && ".
 366        "git tag -m \"sync $(date)\" -a -f ${syncname} ${masterrev}");
 367
 368 print STDERR "loading dump into svn\n" if ($verbose);
 369
 370 system("svnadmin load $svntree < $svndump >>$log 2>&1") == 0 or
 371     die "svnadmin load";
 372
 373 unlink $svndump, $gitdump, $log;
 374
 375 exit 0;
 376
 377
 378 __END__
 379
 380 =head1 NAME
 381
 382 git2svn - converts a git branch to a svn ditto
 383
 384 =head1 SYNOPSIS
 385
 386 git2svn [options] git-repro svn-repro
 387
 388 =head OPTIONS
 389
 390 =over 8
 391
 392 =item B<-git-branch>
 393
 394 The git branch to export. The default is branch is master.
 395
 396 =item B<-svn-prefix>
 397
 398 The svn prefix where the branch is import. The default is trunk to
 399 match the default GIT branch (master).
 400
 401 =item B<-verbose>
 402
 403 More verbose output, can be give more then once to increase the verbosity.
 404
 405 =item B<-help>
 406
 407 Print a brief help message and exits.
 408
 409 =back
 410
 411 =head1 DESCRIPTION
 412
 413 B<This program> will convert a git branch to a svn ditto, it also
 414 support incremantal updates.
 415
 416 =cut
 417