git-svnimport.perl

   1 #!/usr/bin/perl -w
   2
   3 # This tool is copyright (c) 2005, Matthias Urlichs.
   4 # It is released under the Gnu Public License, version 2.
   5 #
   6 # The basic idea is to pull and analyze SVN changes.
   7 #
   8 # Checking out the files is done by a single long-running CVS connection
   9 # / server process.
  10 #
  11 # The head revision is on branch "origin" by default.
  12 # You can change that with the '-o' option.
  13
  14 require v5.8.0; # for shell-safe open("-|",LIST)
  15 use strict;
  16 use warnings;
  17 use Getopt::Std;
  18 use File::Spec;
  19 use File::Temp qw(tempfile);
  20 use File::Path qw(mkpath);
  21 use File::Basename qw(basename dirname);
  22 use Time::Local;
  23 use IO::Pipe;
  24 use POSIX qw(strftime dup2);
  25 use IPC::Open2;
  26 use SVN::Core;
  27 use SVN::Ra;
  28
  29 die "Need CVN:COre 1.2.1 or better" if $SVN::Core::VERSION lt "1.2.1";
  30
  31 $SIG{'PIPE'}="IGNORE";
  32 $ENV{'TZ'}="UTC";
  33
  34 our($opt_h,$opt_o,$opt_v,$opt_u,$opt_C,$opt_i,$opt_m,$opt_M,$opt_t,$opt_T,$opt_b,$opt_s,$opt_l);
  35
  36 sub usage() {
  37         print STDERR <<END;
  38 Usage: ${\basename $0}     # fetch/update GIT from CVS
  39        [-o branch-for-HEAD] [-h] [-v] [-l max_num_changes]
  40        [-C GIT_repository] [-t tagname] [-T trunkname] [-b branchname]
  41        [-i] [-u] [-s start_chg] [-m] [-M regex] [SVN_URL]
  42 END
  43         exit(1);
  44 }
  45
  46 getopts("b:C:hil:mM:o:s:t:T:uv") or usage();
  47 usage if $opt_h;
  48
  49 my $tag_name = $opt_t || "tags";
  50 my $trunk_name = $opt_T || "trunk";
  51 my $branch_name = $opt_b || "branches";
  52
  53 @ARGV <= 1 or usage();
  54
  55 $opt_o ||= "origin";
  56 $opt_l = 100 unless defined $opt_l;
  57 my $git_tree = $opt_C;
  58 $git_tree ||= ".";
  59
  60 my $cvs_tree;
  61 if ($#ARGV == 0) {
  62         $cvs_tree = $ARGV[0];
  63 } elsif (-f 'CVS/Repository') {
  64         open my $f, '<', 'CVS/Repository' or
  65             die 'Failed to open CVS/Repository';
  66         $cvs_tree = <$f>;
  67         chomp $cvs_tree;
  68         close $f;
  69 } else {
  70         usage();
  71 }
  72
  73 our @mergerx = ();
  74 if ($opt_m) {
  75         @mergerx = ( qr/\W(?:from|of|merge|merging|merged) (\w+)/i );
  76 }
  77 if ($opt_M) {
  78         push (@mergerx, qr/$opt_M/);
  79 }
  80
  81 select(STDERR); $|=1; select(STDOUT);
  82
  83
  84 package SVNconn;
  85 # Basic SVN connection.
  86 # We're only interested in connecting and downloading, so ...
  87
  88 use File::Spec;
  89 use File::Temp qw(tempfile);
  90 use POSIX qw(strftime dup2);
  91
  92 sub new {
  93         my($what,$repo) = @_;
  94         $what=ref($what) if ref($what);
  95
  96         my $self = {};
  97         $self->{'buffer'} = "";
  98         bless($self,$what);
  99
 100         $repo =~ s#/+$##;
 101         $self->{'fullrep'} = $repo;
 102         $self->conn();
 103
 104         return $self;
 105 }
 106
 107 sub conn {
 108         my $self = shift;
 109         my $repo = $self->{'fullrep'};
 110         my $s = SVN::Ra->new($repo);
 111
 112         die "SVN connection to $repo: $!\n" unless defined $s;
 113         $self->{'svn'} = $s;
 114         $self->{'repo'} = $repo;
 115         $self->{'maxrev'} = $s->get_latest_revnum();
 116 }
 117
 118 sub file {
 119         my($self,$path,$rev) = @_;
 120         my $res;
 121
 122         my ($fh, $name) = tempfile('gitsvn.XXXXXX',
 123                     DIR => File::Spec->tmpdir(), UNLINK => 1);
 124
 125         print "... $rev $path ...\n" if $opt_v;
 126         eval { $self->{'svn'}->get_file($path,$rev,$fh); };
 127         if ($@ and $@ !~ /Attempted to get checksum/) {
 128             # retry
 129             $self->conn();
 130                 eval { $self->{'svn'}->get_file($path,$rev,$fh); };
 131         };
 132         return () if $@ and $@ !~ /Attempted to get checksum/;
 133         die $@ if $@;
 134         close ($fh);
 135
 136         return ($name, $res);
 137 }
 138
 139
 140 package main;
 141
 142 my $svn = SVNconn->new($cvs_tree);
 143
 144
 145 sub pdate($) {
 146         my($d) = @_;
 147         $d =~ m#(\d\d\d\d)-(\d\d)-(\d\d)T(\d\d):(\d\d):(\d\d)#
 148                 or die "Unparseable date: $d\n";
 149         my $y=$1; $y-=1900 if $y>1900;
 150         return timegm($6||0,$5,$4,$3,$2-1,$y);
 151 }
 152
 153 sub getwd() {
 154         my $pwd = `pwd`;
 155         chomp $pwd;
 156         return $pwd;
 157 }
 158
 159
 160 sub get_headref($$) {
 161     my $name    = shift;
 162     my $git_dir = shift;
 163     my $sha;
 164
 165     if (open(C,"$git_dir/refs/heads/$name")) {
 166         chomp($sha = <C>);
 167         close(C);
 168         length($sha) == 40
 169             or die "Cannot get head id for $name ($sha): $!\n";
 170     }
 171     return $sha;
 172 }
 173
 174
 175 -d $git_tree
 176         or mkdir($git_tree,0777)
 177         or die "Could not create $git_tree: $!";
 178 chdir($git_tree);
 179
 180 my $orig_branch = "";
 181 my $forward_master = 0;
 182 my %branches;
 183
 184 my $git_dir = $ENV{"GIT_DIR"} || ".git";
 185 $git_dir = getwd()."/".$git_dir unless $git_dir =~ m#^/#;
 186 $ENV{"GIT_DIR"} = $git_dir;
 187 my $orig_git_index;
 188 $orig_git_index = $ENV{GIT_INDEX_FILE} if exists $ENV{GIT_INDEX_FILE};
 189 my ($git_ih, $git_index) = tempfile('gitXXXXXX', SUFFIX => '.idx',
 190                                     DIR => File::Spec->tmpdir());
 191 close ($git_ih);
 192 $ENV{GIT_INDEX_FILE} = $git_index;
 193 my $maxnum = 0;
 194 my $last_rev = "";
 195 my $last_branch;
 196 my $current_rev = $opt_s ? ($opt_s-1) : 0;
 197 unless(-d $git_dir) {
 198         system("git-init-db");
 199         die "Cannot init the GIT db at $git_tree: $?\n" if $?;
 200         system("git-read-tree");
 201         die "Cannot init an empty tree: $?\n" if $?;
 202
 203         $last_branch = $opt_o;
 204         $orig_branch = "";
 205 } else {
 206         -f "$git_dir/refs/heads/$opt_o"
 207                 or die "Branch '$opt_o' does not exist.\n".
 208                        "Either use the correct '-o branch' option,\n".
 209                        "or import to a new repository.\n";
 210
 211         -f "$git_dir/svn2git"
 212                 or die "'$git_dir/svn2git' does not exist.\n".
 213                        "You need that file for incremental imports.\n";
 214         $last_branch = basename(readlink("$git_dir/HEAD"));
 215         unless($last_branch) {
 216                 warn "Cannot read the last branch name: $! -- assuming 'master'\n";
 217                 $last_branch = "master";
 218         }
 219         $orig_branch = $last_branch;
 220         $last_rev = get_headref($orig_branch, $git_dir);
 221         if (-f "$git_dir/SVN2GIT_HEAD") {
 222                 die <<EOM;
 223 SVN2GIT_HEAD exists.
 224 Make sure your working directory corresponds to HEAD and remove SVN2GIT_HEAD.
 225 You may need to run
 226
 227     git-read-tree -m -u SVN2GIT_HEAD HEAD
 228 EOM
 229         }
 230         system('cp', "$git_dir/HEAD", "$git_dir/SVN2GIT_HEAD");
 231
 232         $forward_master =
 233             $opt_o ne 'master' && -f "$git_dir/refs/heads/master" &&
 234             system('cmp', '-s', "$git_dir/refs/heads/master",
 235                                 "$git_dir/refs/heads/$opt_o") == 0;
 236
 237         # populate index
 238         system('git-read-tree', $last_rev);
 239         die "read-tree failed: $?\n" if $?;
 240
 241         # Get the last import timestamps
 242         open my $B,"<", "$git_dir/svn2git";
 243         while(<$B>) {
 244                 chomp;
 245                 my($num,$branch,$ref) = split;
 246                 $branches{$branch}{$num} = $ref;
 247                 $branches{$branch}{"LAST"} = $ref;
 248                 $current_rev = $num if $current_rev < $num;
 249         }
 250         close($B);
 251 }
 252 -d $git_dir
 253         or die "Could not create git subdir ($git_dir).\n";
 254
 255 open BRANCHES,">>", "$git_dir/svn2git";
 256
 257
 258 ## cvsps output:
 259 #---------------------
 260 #PatchSet 314
 261 #Date: 1999/09/18 13:03:59
 262 #Author: wkoch
 263 #Branch: STABLE-BRANCH-1-0
 264 #Ancestor branch: HEAD
 265 #Tag: (none)
 266 #Log:
 267 #    See ChangeLog: Sat Sep 18 13:03:28 CEST 1999  Werner Koch
 268 #Members:
 269 #       README:1.57->1.57.2.1
 270 #       VERSION:1.96->1.96.2.1
 271 #
 272 #---------------------
 273
 274 my $state = 0;
 275
 276 sub get_file($$$) {
 277         my($rev,$branch,$path) = @_;
 278
 279         # revert split_path(), below
 280         my $svnpath;
 281         $path = "" if $path eq "/"; # this should not happen, but ...
 282         if($branch eq "/") {
 283                 $svnpath = "/$trunk_name/$path";
 284         } elsif($branch =~ m#^/#) {
 285                 $svnpath = "/$tag_name$branch/$path";
 286         } else {
 287                 $svnpath = "/$branch_name/$branch/$path";
 288         }
 289
 290         # now get it
 291         my ($name, $res) = eval { $svn->file($svnpath,$rev); };
 292         return () unless defined $name;
 293
 294         open my $F, '-|', "git-hash-object", "-w", $name
 295                 or die "Cannot create object: $!\n";
 296         my $sha = <$F>;
 297         chomp $sha;
 298         close $F;
 299         my $mode = "0644"; # SV does not seem to store any file modes
 300         return [$mode, $sha, $path];
 301 }
 302
 303 sub split_path($$) {
 304         my($rev,$path) = @_;
 305         my $branch;
 306
 307         if($path =~ s#^/\Q$tag_name\E/([^/]+)/?##) {
 308                 $branch = "/$1";
 309         } elsif($path =~ s#^/\Q$trunk_name\E/?##) {
 310                 $branch = "/";
 311         } elsif($path =~ s#^/\Q$branch_name\E/([^/]+)/?##) {
 312                 $branch = $1;
 313         } else {
 314                 print STDERR "$rev: Unrecognized path: $path\n";
 315                 return ()
 316         }
 317         $path = "/" if $path eq "";
 318         return ($branch,$path);
 319 }
 320
 321 sub commit {
 322         my($branch, $changed_paths, $revision, $author, $date, $message) = @_;
 323         my($author_name,$author_email,$dest);
 324         my(@old,@new);
 325
 326         if (not defined $author) {
 327                 $author_name = $author_email = "unknown";
 328         } elsif ($author =~ /^(.*?)\s+<(.*)>$/) {
 329                 ($author_name, $author_email) = ($1, $2);
 330         } else {
 331                 $author =~ s/^<(.*)>$/$1/;
 332                 $author_name = $author_email = $author;
 333         }
 334         $date = pdate($date);
 335
 336         my $tag;
 337         my $parent;
 338         if($branch eq "/") { # trunk
 339                 $parent = $opt_o;
 340         } elsif($branch =~ m#^/(.+)#) { # tag
 341                 $tag = 1;
 342                 $parent = $1;
 343         } else { # "normal" branch
 344                 # nothing to do
 345                 $parent = $branch;
 346         }
 347         $dest = $parent;
 348
 349         my $prev = $changed_paths->{"/"};
 350         if($prev and $prev->[0] eq "A") {
 351                 delete $changed_paths->{"/"};
 352                 my $oldpath = $prev->[1];
 353                 my $rev;
 354                 if(defined $oldpath) {
 355                         my $p;
 356                         ($parent,$p) = split_path($revision,$oldpath);
 357                         if($parent eq "/") {
 358                                 $parent = $opt_o;
 359                         } else {
 360                                 $parent =~ s#^/##; # if it's a tag
 361                         }
 362                 } else {
 363                         $parent = undef;
 364                 }
 365         }
 366
 367         my $rev;
 368         if($revision > $opt_s and defined $parent) {
 369                 open(H,"git-rev-parse --verify $parent |");
 370                 $rev = <H>;
 371                 close(H) or do {
 372                         print STDERR "$revision: cannot find commit '$parent'!\n";
 373                         return;
 374                 };
 375                 chop $rev;
 376                 if(length($rev) != 40) {
 377                         print STDERR "$revision: cannot find commit '$parent'!\n";
 378                         return;
 379                 }
 380                 $rev = $branches{($parent eq $opt_o) ? "/" : $parent}{"LAST"};
 381                 if($revision != $opt_s and not $rev) {
 382                         print STDERR "$revision: do not know ancestor for '$parent'!\n";
 383                         return;
 384                 }
 385         } else {
 386                 $rev = undef;
 387         }
 388
 389 #       if($prev and $prev->[0] eq "A") {
 390 #               if(not $tag) {
 391 #                       unless(open(H,"> $git_dir/refs/heads/$branch")) {
 392 #                               print STDERR "$revision: Could not create branch $branch: $!\n";
 393 #                               $state=11;
 394 #                               next;
 395 #                       }
 396 #                       print H "$rev\n"
 397 #                               or die "Could not write branch $branch: $!";
 398 #                       close(H)
 399 #                               or die "Could not write branch $branch: $!";
 400 #               }
 401 #       }
 402         if(not defined $rev) {
 403                 unlink($git_index);
 404         } elsif ($rev ne $last_rev) {
 405                 print "Switching from $last_rev to $rev ($branch)\n" if $opt_v;
 406                 system("git-read-tree", $rev);
 407                 die "read-tree failed for $rev: $?\n" if $?;
 408                 $last_rev = $rev;
 409         }
 410
 411         my $cid;
 412         if($tag and not %$changed_paths) {
 413                 $cid = $rev;
 414         } else {
 415                 while(my($path,$action) = each %$changed_paths) {
 416                         if ($action->[0] eq "A") {
 417                                 my $f = get_file($revision,$branch,$path);
 418                                 push(@new,$f) if $f;
 419                         } elsif ($action->[0] eq "D") {
 420                                 push(@old,$path);
 421                         } elsif ($action->[0] eq "M") {
 422                                 my $f = get_file($revision,$branch,$path);
 423                                 push(@new,$f) if $f;
 424                         } elsif ($action->[0] eq "R") {
 425                                 # refer to a file/tree in an earlier commit
 426                                 push(@old,$path); # remove any old stuff
 427
 428                                 # ... and add any new stuff
 429                                 my($b,$p) = split_path($revision,$action->[1]);
 430                                 open my $F,"-|","git-ls-tree","-r","-z", $branches{$b}{$action->[2]}, $p;
 431                                 local $/ = '\0';
 432                                 while(<$F>) {
 433                                         chomp;
 434                                         my($m,$p) = split(/\t/,$_,2);
 435                                         my($mode,$type,$sha1) = split(/ /,$m);
 436                                         next if $type ne "blob";
 437                                         push(@new,[$mode,$sha1,$p]);
 438                                 }
 439                         } else {
 440                                 die "$revision: unknown action '".$action->[0]."' for $path\n";
 441                         }
 442                 }
 443
 444                 if(@old) {
 445                         open my $F, "-|", "git-ls-files", "-z", @old or die $!;
 446                         @old = ();
 447                         local $/ = '\0';
 448                         while(<$F>) {
 449                                 chomp;
 450                                 push(@old,$_);
 451                         }
 452                         close($F);
 453
 454                         while(@old) {
 455                                 my @o2;
 456                                 if(@old > 55) {
 457                                         @o2 = splice(@old,0,50);
 458                                 } else {
 459                                         @o2 = @old;
 460                                         @old = ();
 461                                 }
 462                                 system("git-update-index","--force-remove","--",@o2);
 463                                 die "Cannot remove files: $?\n" if $?;
 464                         }
 465                 }
 466                 while(@new) {
 467                         my @n2;
 468                         if(@new > 12) {
 469                                 @n2 = splice(@new,0,10);
 470                         } else {
 471                                 @n2 = @new;
 472                                 @new = ();
 473                         }
 474                         system("git-update-index","--add",
 475                                 (map { ('--cacheinfo', @$_) } @n2));
 476                         die "Cannot add files: $?\n" if $?;
 477                 }
 478
 479                 my $pid = open(C,"-|");
 480                 die "Cannot fork: $!" unless defined $pid;
 481                 unless($pid) {
 482                         exec("git-write-tree");
 483                         die "Cannot exec git-write-tree: $!\n";
 484                 }
 485                 chomp(my $tree = <C>);
 486                 length($tree) == 40
 487                         or die "Cannot get tree id ($tree): $!\n";
 488                 close(C)
 489                         or die "Error running git-write-tree: $?\n";
 490                 print "Tree ID $tree\n" if $opt_v;
 491
 492                 my $pr = IO::Pipe->new() or die "Cannot open pipe: $!\n";
 493                 my $pw = IO::Pipe->new() or die "Cannot open pipe: $!\n";
 494                 $pid = fork();
 495                 die "Fork: $!\n" unless defined $pid;
 496                 unless($pid) {
 497                         $pr->writer();
 498                         $pw->reader();
 499                         open(OUT,">&STDOUT");
 500                         dup2($pw->fileno(),0);
 501                         dup2($pr->fileno(),1);
 502                         $pr->close();
 503                         $pw->close();
 504
 505                         my @par = ();
 506                         @par = ("-p",$rev) if defined $rev;
 507
 508                         # loose detection of merges
 509                         # based on the commit msg
 510                         foreach my $rx (@mergerx) {
 511                                 if ($message =~ $rx) {
 512                                         my $mparent = $1;
 513                                         if ($mparent eq 'HEAD') { $mparent = $opt_o };
 514                                         if ( -e "$git_dir/refs/heads/$mparent") {
 515                                                 $mparent = get_headref($mparent, $git_dir);
 516                                                 push @par, '-p', $mparent;
 517                                                 print OUT "Merge parent branch: $mparent\n" if $opt_v;
 518                                         }
 519                                 }
 520                         }
 521
 522                         exec("env",
 523                                 "GIT_AUTHOR_NAME=$author_name",
 524                                 "GIT_AUTHOR_EMAIL=$author_email",
 525                                 "GIT_AUTHOR_DATE=".strftime("+0000 %Y-%m-%d %H:%M:%S",gmtime($date)),
 526                                 "GIT_COMMITTER_NAME=$author_name",
 527                                 "GIT_COMMITTER_EMAIL=$author_email",
 528                                 "GIT_COMMITTER_DATE=".strftime("+0000 %Y-%m-%d %H:%M:%S",gmtime($date)),
 529                                 "git-commit-tree", $tree,@par);
 530                         die "Cannot exec git-commit-tree: $!\n";
 531                 }
 532                 $pw->writer();
 533                 $pr->reader();
 534
 535                 $message =~ s/[\s\n]+\z//;
 536
 537                 print $pw "$message\n"
 538                         or die "Error writing to git-commit-tree: $!\n";
 539                 $pw->close();
 540
 541                 print "Committed change $revision:$branch ".strftime("%Y-%m-%d %H:%M:%S",gmtime($date)).")\n" if $opt_v;
 542                 chomp($cid = <$pr>);
 543                 length($cid) == 40
 544                         or die "Cannot get commit id ($cid): $!\n";
 545                 print "Commit ID $cid\n" if $opt_v;
 546                 $pr->close();
 547
 548                 waitpid($pid,0);
 549                 die "Error running git-commit-tree: $?\n" if $?;
 550         }
 551
 552         if(not defined $dest) {
 553                 print "... no known parent\n" if $opt_v;
 554         } elsif(not $tag) {
 555                 print "Writing to refs/heads/$dest\n" if $opt_v;
 556                 open(C,">$git_dir/refs/heads/$dest") and
 557                 print C ("$cid\n") and
 558                 close(C)
 559                         or die "Cannot write branch $dest for update: $!\n";
 560         }
 561
 562         if($tag) {
 563                 my($in, $out) = ('','');
 564                 $last_rev = "-" if %$changed_paths;
 565                 # the tag was 'complex', i.e. did not refer to a "real" revision
 566
 567                 $dest =~ tr/_/\./ if $opt_u;
 568
 569                 my $pid = open2($in, $out, 'git-mktag');
 570                 print $out ("object $cid\n".
 571                     "type commit\n".
 572                     "tag $dest\n".
 573                     "tagger $author_name <$author_email>\n") and
 574                 close($out)
 575                     or die "Cannot create tag object $dest: $!\n";
 576
 577                 my $tagobj = <$in>;
 578                 chomp $tagobj;
 579
 580                 if ( !close($in) or waitpid($pid, 0) != $pid or
 581                                 $? != 0 or $tagobj !~ /^[0123456789abcdef]{40}$/ ) {
 582                         die "Cannot create tag object $dest: $!\n";
 583                 }
 584
 585                 open(C,">$git_dir/refs/tags/$dest") and
 586                 print C ("$tagobj\n") and
 587                 close(C)
 588                         or die "Cannot create tag $branch: $!\n";
 589
 590                 print "Created tag '$dest' on '$branch'\n" if $opt_v;
 591         }
 592         $branches{$branch}{"LAST"} = $cid;
 593         $branches{$branch}{$revision} = $cid;
 594         $last_rev = $cid;
 595         print BRANCHES "$revision $branch $cid\n";
 596         print "DONE: $revision $dest $cid\n" if $opt_v;
 597 }
 598
 599 my ($changed_paths, $revision, $author, $date, $message, $pool) = @_;
 600 sub _commit_all {
 601         ($changed_paths, $revision, $author, $date, $message, $pool) = @_;
 602         my %p;
 603         while(my($path,$action) = each %$changed_paths) {
 604                 $p{$path} = [ $action->action,$action->copyfrom_path, $action->copyfrom_rev ];
 605         }
 606         $changed_paths = \%p;
 607 }
 608
 609 sub commit_all {
 610         my %done;
 611         my @col;
 612         my $pref;
 613         my $branch;
 614
 615         while(my($path,$action) = each %$changed_paths) {
 616                 ($branch,$path) = split_path($revision,$path);
 617                 next if not defined $branch;
 618                 $done{$branch}{$path} = $action;
 619         }
 620         while(($branch,$changed_paths) = each %done) {
 621                 commit($branch, $changed_paths, $revision, $author, $date, $message);
 622         }
 623 }
 624
 625 while(++$current_rev < $svn->{'maxrev'}) {
 626         $svn->{'svn'}->get_log("/",$current_rev,$current_rev,$current_rev,1,1,\&_commit_all,"");
 627         commit_all();
 628         if($opt_l and not --$opt_l) {
 629                 print STDERR "Exiting due to a memory leak. Repeat, please.\n";
 630                 last;
 631         }
 632 }
 633
 634
 635 unlink($git_index);
 636
 637 if (defined $orig_git_index) {
 638         $ENV{GIT_INDEX_FILE} = $orig_git_index;
 639 } else {
 640         delete $ENV{GIT_INDEX_FILE};
 641 }
 642
 643 # Now switch back to the branch we were in before all of this happened
 644 if($orig_branch) {
 645         print "DONE\n" if $opt_v and (not defined $opt_l or $opt_l > 0);
 646         system("cp","$git_dir/refs/heads/$opt_o","$git_dir/refs/heads/master")
 647                 if $forward_master;
 648         unless ($opt_i) {
 649                 system('git-read-tree', '-m', '-u', 'SVN2GIT_HEAD', 'HEAD');
 650                 die "read-tree failed: $?\n" if $?;
 651         }
 652 } else {
 653         $orig_branch = "master";
 654         print "DONE; creating $orig_branch branch\n" if $opt_v and (not defined $opt_l or $opt_l > 0);
 655         system("cp","$git_dir/refs/heads/$opt_o","$git_dir/refs/heads/master")
 656                 unless -f "$git_dir/refs/heads/master";
 657         unlink("$git_dir/HEAD");
 658         symlink("refs/heads/$orig_branch","$git_dir/HEAD");
 659         unless ($opt_i) {
 660                 system('git checkout');
 661                 die "checkout failed: $?\n" if $?;
 662         }
 663 }
 664 unlink("$git_dir/SVN2GIT_HEAD");
 665 close(BRANCHES);