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 $SIG{'PIPE'}="IGNORE";
  30 $ENV{'TZ'}="UTC";
  31
  32 our($opt_h,$opt_o,$opt_v,$opt_u,$opt_C,$opt_i,$opt_m,$opt_M,$opt_t,$opt_T,$opt_b);
  33
  34 sub usage() {
  35         print STDERR <<END;
  36 Usage: ${\basename $0}     # fetch/update GIT from CVS
  37        [-o branch-for-HEAD] [-h] [-v]
  38        [-C GIT_repository] [-t tagname] [-T trunkname] [-b branchname]
  39        [-i] [-u] [-s subst] [-m] [-M regex] [SVN_URL]
  40 END
  41         exit(1);
  42 }
  43
  44 getopts("b:C:hivmM:o:t:T:u") or usage();
  45 usage if $opt_h;
  46
  47 my $tag_name = $opt_t || "tags";
  48 my $trunk_name = $opt_T || "trunk";
  49 my $branch_name = $opt_b || "branches";
  50
  51 @ARGV <= 1 or usage();
  52
  53 $opt_o ||= "origin";
  54 my $git_tree = $opt_C;
  55 $git_tree ||= ".";
  56
  57 my $cvs_tree;
  58 if ($#ARGV == 0) {
  59         $cvs_tree = $ARGV[0];
  60 } elsif (-f 'CVS/Repository') {
  61         open my $f, '<', 'CVS/Repository' or
  62             die 'Failed to open CVS/Repository';
  63         $cvs_tree = <$f>;
  64         chomp $cvs_tree;
  65         close $f;
  66 } else {
  67         usage();
  68 }
  69
  70 our @mergerx = ();
  71 if ($opt_m) {
  72         @mergerx = ( qr/\W(?:from|of|merge|merging|merged) (\w+)/i );
  73 }
  74 if ($opt_M) {
  75         push (@mergerx, qr/$opt_M/);
  76 }
  77
  78 select(STDERR); $|=1; select(STDOUT);
  79
  80
  81 package SVNconn;
  82 # Basic SVN connection.
  83 # We're only interested in connecting and downloading, so ...
  84
  85 use File::Spec;
  86 use File::Temp qw(tempfile);
  87 use POSIX qw(strftime dup2);
  88
  89 sub new {
  90         my($what,$repo) = @_;
  91         $what=ref($what) if ref($what);
  92
  93         my $self = {};
  94         $self->{'buffer'} = "";
  95         bless($self,$what);
  96
  97         $repo =~ s#/+$##;
  98         $self->{'fullrep'} = $repo;
  99         $self->conn();
 100
 101         $self->{'lines'} = undef;
 102
 103         return $self;
 104 }
 105
 106 sub conn {
 107         my $self = shift;
 108         my $repo = $self->{'fullrep'};
 109         my $s = SVN::Ra->new($repo);
 110
 111         die "SVN connection to $repo: $!\n" unless defined $s;
 112         $self->{'svn'} = $s;
 113         $self->{'repo'} = $repo;
 114         $self->{'maxrev'} = $s->get_latest_revnum();
 115 }
 116
 117 sub file {
 118         my($self,$path,$rev) = @_;
 119         my $res;
 120
 121         my ($fh, $name) = tempfile('gitsvn.XXXXXX',
 122                     DIR => File::Spec->tmpdir(), UNLINK => 1);
 123
 124         $self->{'svn'}->get_file($path,$rev,$fh) or do {
 125             # retry
 126             $self->conn();
 127                 $self->{'svn'}->get_file($path,$rev,$fh)
 128                     or die "$rev: No file $path at $rev\n";
 129         };
 130         close ($fh);
 131
 132         return ($name, $res);
 133 }
 134
 135
 136 package main;
 137
 138 my $svn = SVNconn->new($cvs_tree);
 139
 140
 141 sub pdate($) {
 142         my($d) = @_;
 143         $d =~ m#(\d\d\d\d)-(\d\d)-(\d\d)T(\d\d):(\d\d):(\d\d)#
 144                 or die "Unparseable date: $d\n";
 145         my $y=$1; $y-=1900 if $y>1900;
 146         return timegm($6||0,$5,$4,$3,$2-1,$y);
 147 }
 148
 149 sub pmode($) {
 150         my($mode) = @_;
 151         my $m = 0;
 152         my $mm = 0;
 153         my $um = 0;
 154         for my $x(split(//,$mode)) {
 155                 if($x eq ",") {
 156                         $m |= $mm&$um;
 157                         $mm = 0;
 158                         $um = 0;
 159                 } elsif($x eq "u") { $um |= 0700;
 160                 } elsif($x eq "g") { $um |= 0070;
 161                 } elsif($x eq "o") { $um |= 0007;
 162                 } elsif($x eq "r") { $mm |= 0444;
 163                 } elsif($x eq "w") { $mm |= 0222;
 164                 } elsif($x eq "x") { $mm |= 0111;
 165                 } elsif($x eq "=") { # do nothing
 166                 } else { die "Unknown mode: $mode\n";
 167                 }
 168         }
 169         $m |= $mm&$um;
 170         return $m;
 171 }
 172
 173 sub getwd() {
 174         my $pwd = `pwd`;
 175         chomp $pwd;
 176         return $pwd;
 177 }
 178
 179
 180 sub get_headref($$) {
 181     my $name    = shift;
 182     my $git_dir = shift;
 183     my $sha;
 184
 185     if (open(C,"$git_dir/refs/heads/$name")) {
 186         chomp($sha = <C>);
 187         close(C);
 188         length($sha) == 40
 189             or die "Cannot get head id for $name ($sha): $!\n";
 190     }
 191     return $sha;
 192 }
 193
 194
 195 -d $git_tree
 196         or mkdir($git_tree,0777)
 197         or die "Could not create $git_tree: $!";
 198 chdir($git_tree);
 199
 200 my $orig_branch = "";
 201 my $forward_master = 0;
 202 my %branches;
 203
 204 my $git_dir = $ENV{"GIT_DIR"} || ".git";
 205 $git_dir = getwd()."/".$git_dir unless $git_dir =~ m#^/#;
 206 $ENV{"GIT_DIR"} = $git_dir;
 207 my $orig_git_index;
 208 $orig_git_index = $ENV{GIT_INDEX_FILE} if exists $ENV{GIT_INDEX_FILE};
 209 my ($git_ih, $git_index) = tempfile('gitXXXXXX', SUFFIX => '.idx',
 210                                     DIR => File::Spec->tmpdir());
 211 close ($git_ih);
 212 $ENV{GIT_INDEX_FILE} = $git_index;
 213 my $maxnum = 0;
 214 my $last_rev = "";
 215 my $last_branch;
 216 my $current_rev = 0;
 217 unless(-d $git_dir) {
 218         system("git-init-db");
 219         die "Cannot init the GIT db at $git_tree: $?\n" if $?;
 220         system("git-read-tree");
 221         die "Cannot init an empty tree: $?\n" if $?;
 222
 223         $last_branch = $opt_o;
 224         $orig_branch = "";
 225 } else {
 226         -f "$git_dir/refs/heads/$opt_o"
 227                 or die "Branch '$opt_o' does not exist.\n".
 228                        "Either use the correct '-o branch' option,\n".
 229                        "or import to a new repository.\n";
 230
 231         -f "$git_dir/svn2git"
 232                 or die "'$git_dir/svn2git' does not exist.\n".
 233                        "You need that file for incremental imports.\n";
 234         $last_branch = basename(readlink("$git_dir/HEAD"));
 235         unless($last_branch) {
 236                 warn "Cannot read the last branch name: $! -- assuming 'master'\n";
 237                 $last_branch = "master";
 238         }
 239         $orig_branch = $last_branch;
 240         $last_rev = get_headref($orig_branch, $git_dir);
 241         if (-f "$git_dir/SVN2GIT_HEAD") {
 242                 die <<EOM;
 243 SVN2GIT_HEAD exists.
 244 Make sure your working directory corresponds to HEAD and remove SVN2GIT_HEAD.
 245 You may need to run
 246
 247     git-read-tree -m -u SVN2GIT_HEAD HEAD
 248 EOM
 249         }
 250         system('cp', "$git_dir/HEAD", "$git_dir/SVN2GIT_HEAD");
 251
 252         $forward_master =
 253             $opt_o ne 'master' && -f "$git_dir/refs/heads/master" &&
 254             system('cmp', '-s', "$git_dir/refs/heads/master",
 255                                 "$git_dir/refs/heads/$opt_o") == 0;
 256
 257         # populate index
 258         system('git-read-tree', $last_rev);
 259         die "read-tree failed: $?\n" if $?;
 260
 261         # Get the last import timestamps
 262         open my $B,"<", "$git_dir/svn2git";
 263         while(<$B>) {
 264                 chomp;
 265                 my($num,$branch,$ref) = split;
 266                 $branches{$branch}{$num} = $ref;
 267                 $branches{$branch}{"LAST"} = $ref;
 268                 $current_rev = $num+1 if $current_rev < $num+1;
 269         }
 270         close($B);
 271 }
 272 -d $git_dir
 273         or die "Could not create git subdir ($git_dir).\n";
 274
 275 open BRANCHES,">>", "$git_dir/svn2git";
 276
 277
 278 ## cvsps output:
 279 #---------------------
 280 #PatchSet 314
 281 #Date: 1999/09/18 13:03:59
 282 #Author: wkoch
 283 #Branch: STABLE-BRANCH-1-0
 284 #Ancestor branch: HEAD
 285 #Tag: (none)
 286 #Log:
 287 #    See ChangeLog: Sat Sep 18 13:03:28 CEST 1999  Werner Koch
 288 #Members:
 289 #       README:1.57->1.57.2.1
 290 #       VERSION:1.96->1.96.2.1
 291 #
 292 #---------------------
 293
 294 my $state = 0;
 295
 296 sub get_file($$$) {
 297         my($rev,$branch,$path) = @_;
 298
 299         # revert split_path(), below
 300         my $svnpath;
 301         $path = "" if $path eq "/"; # this should not happen, but ...
 302         if($branch eq "/") {
 303                 $svnpath = "/$trunk_name/$path";
 304         } elsif($branch =~ m#^/#) {
 305                 $svnpath = "/$tag_name$branch/$path";
 306         } else {
 307                 $svnpath = "/$branch_name/$branch/$path";
 308         }
 309
 310         # now get it
 311         my ($name, $res) = $svn->file($svnpath,$rev);
 312
 313         open my $F, '-|', "git-hash-object -w $name"
 314                 or die "Cannot create object: $!\n";
 315         my $sha = <$F>;
 316         chomp $sha;
 317         close $F;
 318         # my $mode = pmode($cvs->{'mode'});
 319         my $mode = "0644"; # SV does not seem to store any file modes
 320         return [$mode, $sha, $path];
 321 }
 322
 323 sub split_path($$) {
 324         my($rev,$path) = @_;
 325         my $branch;
 326
 327         if($path =~ s#^/\Q$tag_name\E/([^/]+)/?##) {
 328                 $branch = "/$1";
 329         } elsif($path =~ s#^/\Q$trunk_name\E/?##) {
 330                 $branch = "/";
 331         } elsif($path =~ s#^/\Q$branch_name\E/([^/]+)/?##) {
 332                 $branch = $1;
 333         } else {
 334                 print STDERR "$rev: Unrecognized path: $path\n";
 335                 return ()
 336         }
 337         $path = "/" if $path eq "";
 338         return ($branch,$path);
 339 }
 340
 341 sub commit {
 342         my($branch, $changed_paths, $revision, $author, $date, $message) = @_;
 343         my($author_name,$author_email,$dest);
 344         my(@old,@new);
 345
 346         if ($author =~ /^(.*?)\s+<(.*)>$/) {
 347                 ($author_name, $author_email) = ($1, $2);
 348         } else {
 349                 $author =~ s/^<(.*)>$/$1/;
 350                 $author_name = $author_email = $author;
 351         }
 352         $date = pdate($date);
 353
 354         my $tag;
 355         my $parent;
 356         if($branch eq "/") { # trunk
 357                 $parent = $opt_o;
 358         } elsif($branch =~ m#^/(.+)#) { # tag
 359                 $tag = 1;
 360                 $parent = $1;
 361         } else { # "normal" branch
 362                 # nothing to do
 363                 $parent = $branch;
 364         }
 365         $dest = $parent;
 366
 367         my $prev = $changed_paths->{"/"};
 368         if($prev and $prev->action eq "A") {
 369                 delete $changed_paths->{"/"};
 370                 my $oldpath = $prev->copyfrom_path;
 371                 my $rev;
 372                 if(defined $oldpath) {
 373                         my $p;
 374                         ($parent,$p) = split_path($revision,$oldpath);
 375                         if($parent eq "/") {
 376                                 $parent = $opt_o;
 377                         } else {
 378                                 $parent =~ s#^/##; # if it's a tag
 379                         }
 380                 } else {
 381                         $parent = undef;
 382                 }
 383         }
 384
 385         my $rev;
 386         if(defined $parent) {
 387                 open(H,"git-rev-parse --verify $parent |");
 388                 $rev = <H>;
 389                 close(H) or do {
 390                         print STDERR "$revision: cannot find commit '$parent'!\n";
 391                         return;
 392                 };
 393                 chop $rev;
 394                 if(length($rev) != 40) {
 395                         print STDERR "$revision: cannot find commit '$parent'!\n";
 396                         return;
 397                 }
 398                 $rev = $branches{($parent eq $opt_o) ? "/" : $parent}{"LAST"};
 399                 if($revision != 1 and not $rev) {
 400                         print STDERR "$revision: do not know ancestor for '$parent'!\n";
 401                         return;
 402                 }
 403         } else {
 404                 $rev = undef;
 405         }
 406
 407 #       if($prev and $prev->action eq "A") {
 408 #               if(not $tag) {
 409 #                       unless(open(H,"> $git_dir/refs/heads/$branch")) {
 410 #                               print STDERR "$revision: Could not create branch $branch: $!\n";
 411 #                               $state=11;
 412 #                               next;
 413 #                       }
 414 #                       print H "$rev\n"
 415 #                               or die "Could not write branch $branch: $!";
 416 #                       close(H)
 417 #                               or die "Could not write branch $branch: $!";
 418 #               }
 419 #       }
 420         if(not defined $rev) {
 421                 unlink($git_index);
 422         } elsif ($rev ne $last_rev) {
 423                 print "Switching from $last_rev to $rev ($branch)\n" if $opt_v;
 424                 system("git-read-tree", $rev);
 425                 die "read-tree failed for $rev: $?\n" if $?;
 426                 $last_rev = $rev;
 427         }
 428
 429         while(my($path,$action) = each %$changed_paths) {
 430                 if ($action->action eq "A") {
 431                         my $f = get_file($revision,$branch,$path);
 432                         push(@new,$f) if $f;
 433                 } elsif ($action->action eq "D") {
 434                         push(@old,$path);
 435                 } elsif ($action->action eq "M") {
 436                         my $f = get_file($revision,$branch,$path);
 437                         push(@new,$f) if $f;
 438                 } elsif ($action->action eq "R") {
 439                         # refer to a file/tree in an earlier commit
 440                         push(@old,$path); # remove any old stuff
 441
 442                         # ... and add any new stuff
 443                         my($b,$p) = split_path($revision,$action->oldpath);
 444                         open my $F,"-|","git-ls-tree","-r","-z", $branches{$b}{$action->oldrev}, $p;
 445                         local $/ = '\0';
 446                         while(<$F>) {
 447                                 chomp;
 448                                 my($m,$p) = split(/\t/,$_,2);
 449                                 my($mode,$type,$sha1) = split(/ /,$m);
 450                                 next if $type ne "blob";
 451                                 push(@new,[$mode,$sha1,$p]);
 452                         }
 453                 } else {
 454                         die "$revision: unknown action '".$action->action."' for $path\n";
 455                 }
 456         }
 457
 458         if(@old) {
 459                 open F, "-│", "git-ls-files", "-z", @old or die $!;
 460                 @old = ();
 461                 local $/ = '\0';
 462                 while(<F>) {
 463                         chomp;
 464                         push(@old,$_);
 465                 }
 466                 close(F);
 467
 468                 while(@old) {
 469                         my @o2;
 470                         if(@old > 55) {
 471                                 @o2 = splice(@old,0,50);
 472                         } else {
 473                                 @o2 = @old;
 474                                 @old = ();
 475                         }
 476                         system("git-update-index","--force-remove","--",@o2);
 477                         die "Cannot remove files: $?\n" if $?;
 478                 }
 479         }
 480         while(@new) {
 481                 my @n2;
 482                 if(@new > 12) {
 483                         @n2 = splice(@new,0,10);
 484                 } else {
 485                         @n2 = @new;
 486                         @new = ();
 487                 }
 488                 system("git-update-index","--add",
 489                         (map { ('--cacheinfo', @$_) } @n2));
 490                 die "Cannot add files: $?\n" if $?;
 491         }
 492
 493         my $pid = open(C,"-|");
 494         die "Cannot fork: $!" unless defined $pid;
 495         unless($pid) {
 496                 exec("git-write-tree");
 497                 die "Cannot exec git-write-tree: $!\n";
 498         }
 499         chomp(my $tree = <C>);
 500         length($tree) == 40
 501                 or die "Cannot get tree id ($tree): $!\n";
 502         close(C)
 503                 or die "Error running git-write-tree: $?\n";
 504         print "Tree ID $tree\n" if $opt_v;
 505
 506         my $pr = IO::Pipe->new() or die "Cannot open pipe: $!\n";
 507         my $pw = IO::Pipe->new() or die "Cannot open pipe: $!\n";
 508         $pid = fork();
 509         die "Fork: $!\n" unless defined $pid;
 510         unless($pid) {
 511                 $pr->writer();
 512                 $pw->reader();
 513                 open(OUT,">&STDOUT");
 514                 dup2($pw->fileno(),0);
 515                 dup2($pr->fileno(),1);
 516                 $pr->close();
 517                 $pw->close();
 518
 519                 my @par = ();
 520                 @par = ("-p",$rev) if defined $rev;
 521
 522                 # loose detection of merges
 523                 # based on the commit msg
 524                 foreach my $rx (@mergerx) {
 525                         if ($message =~ $rx) {
 526                                 my $mparent = $1;
 527                                 if ($mparent eq 'HEAD') { $mparent = $opt_o };
 528                                 if ( -e "$git_dir/refs/heads/$mparent") {
 529                                         $mparent = get_headref($mparent, $git_dir);
 530                                         push @par, '-p', $mparent;
 531                                         print OUT "Merge parent branch: $mparent\n" if $opt_v;
 532                                 }
 533                         }
 534                 }
 535
 536                 exec("env",
 537                         "GIT_AUTHOR_NAME=$author_name",
 538                         "GIT_AUTHOR_EMAIL=$author_email",
 539                         "GIT_AUTHOR_DATE=".strftime("+0000 %Y-%m-%d %H:%M:%S",gmtime($date)),
 540                         "GIT_COMMITTER_NAME=$author_name",
 541                         "GIT_COMMITTER_EMAIL=$author_email",
 542                         "GIT_COMMITTER_DATE=".strftime("+0000 %Y-%m-%d %H:%M:%S",gmtime($date)),
 543                         "git-commit-tree", $tree,@par);
 544                 die "Cannot exec git-commit-tree: $!\n";
 545         }
 546         $pw->writer();
 547         $pr->reader();
 548
 549         $message =~ s/[\s\n]+\z//;
 550
 551         print $pw "$message\n"
 552                 or die "Error writing to git-commit-tree: $!\n";
 553         $pw->close();
 554
 555         print "Committed change $revision:$branch ".strftime("%Y-%m-%d %H:%M:%S",gmtime($date)).")\n" if $opt_v;
 556         chomp(my $cid = <$pr>);
 557         length($cid) == 40
 558                 or die "Cannot get commit id ($cid): $!\n";
 559         print "Commit ID $cid\n" if $opt_v;
 560         $pr->close();
 561
 562         waitpid($pid,0);
 563         die "Error running git-commit-tree: $?\n" if $?;
 564
 565         if(defined $dest) {
 566                 print "Writing to refs/heads/$dest\n" if $opt_v;
 567                 open(C,">$git_dir/refs/heads/$dest") and
 568                 print C ("$cid\n") and
 569                 close(C)
 570                         or die "Cannot write branch $dest for update: $!\n";
 571         } else {
 572                 print "... no known parent\n" if $opt_v;
 573         }
 574         $branches{$branch}{"LAST"} = $cid;
 575         $branches{$branch}{$revision} = $cid;
 576         $last_rev = $cid;
 577         print BRANCHES "$revision $branch $cid\n";
 578         print "DONE: $revision $dest $cid\n" if $opt_v;
 579
 580         if($tag) {
 581                 my($in, $out) = ('','');
 582                 $last_rev = "-" if %$changed_paths;
 583                 # the tag was 'complex', i.e. did not refer to a "real" revision
 584
 585                 $tag =~ tr/_/\./ if $opt_u;
 586
 587                 my $pid = open2($in, $out, 'git-mktag');
 588                 print $out ("object $cid\n".
 589                     "type commit\n".
 590                     "tag $tag\n".
 591                     "tagger $author_name <$author_email>\n") and
 592                 close($out)
 593                     or die "Cannot create tag object $tag: $!\n";
 594
 595                 my $tagobj = <$in>;
 596                 chomp $tagobj;
 597
 598                 if ( !close($in) or waitpid($pid, 0) != $pid or
 599                                 $? != 0 or $tagobj !~ /^[0123456789abcdef]{40}$/ ) {
 600                         die "Cannot create tag object $tag: $!\n";
 601                 }
 602
 603
 604                 open(C,">$git_dir/refs/tags/$tag")
 605                         or die "Cannot create tag $tag: $!\n";
 606                 print C "$tagobj\n"
 607                         or die "Cannot write tag $tag: $!\n";
 608                 close(C)
 609                         or die "Cannot write tag $tag: $!\n";
 610
 611                 print "Created tag '$tag' on '$branch'\n" if $opt_v;
 612         }
 613 }
 614
 615 my ($changed_paths, $revision, $author, $date, $message, $pool) = @_;
 616 sub _commit_all {
 617         ($changed_paths, $revision, $author, $date, $message, $pool) = @_;
 618 }
 619 sub commit_all {
 620         my %done;
 621         my @col;
 622         my $pref;
 623         my $branch;
 624
 625         while(my($path,$action) = each %$changed_paths) {
 626                 ($branch,$path) = split_path($revision,$path);
 627                 next if not defined $branch;
 628                 $done{$branch}{$path} = $action;
 629         }
 630         while(($branch,$changed_paths) = each %done) {
 631                 commit($branch, $changed_paths, $revision, $author, $date, $message);
 632         }
 633 }
 634
 635 while(++$current_rev < $svn->{'maxrev'}) {
 636         $svn->{'svn'}->get_log("/",$current_rev,$current_rev,$current_rev,1,1,\&_commit_all,"");
 637         commit_all();
 638 }
 639
 640
 641 unlink($git_index);
 642
 643 if (defined $orig_git_index) {
 644         $ENV{GIT_INDEX_FILE} = $orig_git_index;
 645 } else {
 646         delete $ENV{GIT_INDEX_FILE};
 647 }
 648
 649 # Now switch back to the branch we were in before all of this happened
 650 if($orig_branch) {
 651         print "DONE\n" if $opt_v;
 652         system("cp","$git_dir/refs/heads/$opt_o","$git_dir/refs/heads/master")
 653                 if $forward_master;
 654         unless ($opt_i) {
 655                 system('git-read-tree', '-m', '-u', 'SVN2GIT_HEAD', 'HEAD');
 656                 die "read-tree failed: $?\n" if $?;
 657         }
 658 } else {
 659         $orig_branch = "master";
 660         print "DONE; creating $orig_branch branch\n" if $opt_v;
 661         system("cp","$git_dir/refs/heads/$opt_o","$git_dir/refs/heads/master")
 662                 unless -f "$git_dir/refs/heads/master";
 663         unlink("$git_dir/HEAD");
 664         symlink("refs/heads/$orig_branch","$git_dir/HEAD");
 665         unless ($opt_i) {
 666                 system('git checkout');
 667                 die "checkout failed: $?\n" if $?;
 668         }
 669 }
 670 unlink("$git_dir/SVN2GIT_HEAD");
 671 close(BRANCHES);