+{
+my $ret;
+sub git_find_root {
+ # The wiki may not be the only thing in the git repo.
+ # Determine if it is in a subdirectory by examining the srcdir,
+ # and its parents, looking for the .git directory.
+
+ return @$ret if defined $ret;
+
+ my $subdir="";
+ my $dir=$config{srcdir};
+ while (! -d "$dir/.git") {
+ $subdir=IkiWiki::basename($dir)."/".$subdir;
+ $dir=IkiWiki::dirname($dir);
+ if (! length $dir) {
+ error("cannot determine root of git repo");
+ }
+ }
+
+ $ret=[$subdir, $dir];
+ return @$ret;
+}
+
+}
+
+sub git_parse_changes {
+ my $reverted = shift;
+ my @changes = @_;
+
+ my ($subdir, $rootdir) = git_find_root();
+ my @rets;
+ foreach my $ci (@changes) {
+ foreach my $detail (@{ $ci->{'details'} }) {
+ my $file = $detail->{'file'};
+
+ # check that all changed files are in the subdir
+ if (length $subdir &&
+ ! ($file =~ s/^\Q$subdir\E//)) {
+ error sprintf(gettext("you are not allowed to change %s"), $file);
+ }
+
+ my ($action, $mode, $path);
+ if ($detail->{'status'} =~ /^[M]+\d*$/) {
+ $action="change";
+ $mode=$detail->{'mode_to'};
+ }
+ elsif ($detail->{'status'} =~ /^[AM]+\d*$/) {
+ $action= $reverted ? "remove" : "add";
+ $mode=$detail->{'mode_to'};
+ }
+ elsif ($detail->{'status'} =~ /^[DAM]+\d*/) {
+ $action= $reverted ? "add" : "remove";
+ $mode=$detail->{'mode_from'};
+ }
+ else {
+ error "unknown status ".$detail->{'status'};
+ }
+
+ # test that the file mode is ok
+ if ($mode !~ /^100[64][64][64]$/) {
+ error sprintf(gettext("you cannot act on a file with mode %s"), $mode);
+ }
+ if ($action eq "change") {
+ if ($detail->{'mode_from'} ne $detail->{'mode_to'}) {
+ error gettext("you are not allowed to change file modes");
+ }
+ }
+
+ # extract attachment to temp file
+ if (($action eq 'add' || $action eq 'change') &&
+ ! pagetype($file)) {
+ eval q{use File::Temp};
+ die $@ if $@;
+ my $fh;
+ ($fh, $path)=File::Temp::tempfile(undef, UNLINK => 1);
+ my $cmd = "cd $git_dir && ".
+ "git show $detail->{sha1_to} > '$path'";
+ if (system($cmd) != 0) {
+ error("failed writing temp file '$path'.");
+ }
+ }
+
+ push @rets, {
+ file => $file,
+ action => $action,
+ path => $path,
+ };
+ }
+ }
+
+ return @rets;
+}
+
+sub rcs_receive () {
+ my @rets;
+ while (<>) {
+ chomp;
+ my ($oldrev, $newrev, $refname) = split(' ', $_, 3);
+
+ # only allow changes to gitmaster_branch
+ if ($refname !~ /^refs\/heads\/\Q$config{gitmaster_branch}\E$/) {
+ error sprintf(gettext("you are not allowed to change %s"), $refname);
+ }
+
+ # Avoid chdir when running git here, because the changes
+ # are in the master git repo, not the srcdir repo.
+ # (Also, if a subdir is involved, we don't want to chdir to
+ # it and only see changes in it.)
+ # The pre-receive hook already puts us in the right place.
+ $git_dir=".";
+ push @rets, git_parse_changes(0, git_commit_info($oldrev."..".$newrev));
+ $git_dir=undef;
+ }
+
+ return reverse @rets;
+}
+
+sub rcs_preprevert ($) {
+ my $rev=shift;
+ my ($sha1) = $rev =~ /^($sha1_pattern)$/; # untaint
+
+ # Examine changes from root of git repo, not from any subdir,
+ # in order to see all changes.
+ my ($subdir, $rootdir) = git_find_root();
+ $git_dir=$rootdir;
+
+ my @commits=git_commit_info($sha1, 1);
+ if (! @commits) {
+ error "unknown commit"; # just in case
+ }
+
+ # git revert will fail on merge commits. Add a nice message.
+ if (exists $commits[0]->{parents} &&
+ @{$commits[0]->{parents}} > 1) {
+ error gettext("you are not allowed to revert a merge");
+ }
+
+ my @ret=git_parse_changes(1, @commits);
+
+ $git_dir=undef;
+ return @ret;
+}
+
+sub rcs_revert ($) {
+ # Try to revert the given rev; returns undef on _success_.
+ my $rev = shift;
+ my ($sha1) = $rev =~ /^($sha1_pattern)$/; # untaint
+
+ if (run_or_non('git', 'revert', '--no-commit', $sha1)) {
+ return undef;
+ }
+ else {
+ run_or_die('git', 'reset', '--hard');
+ return sprintf(gettext("Failed to revert commit %s"), $sha1);
+ }
+}