gitweb: prepare for repositories with packed refs.

When a repository is initialized long time ago with symbolic
HEAD, and "git-pack-refs --prune" is run, HEAD will be a
dangling symlink to refs/heads/ somewhere.

Running -e "$dir/HEAD" to guess if $dir is a git repository does
not give us the right answer anymore in such a case.

Also factor out two places that checked if the repository can be
exported with similar code into a call to a new function,
check_export_ok.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 55d1b2c35529ad73260e3d395f7b2bdba39d0bfc..671a4e6e6f51b569a897a852e288c2a3c1f52bc4 100644 (file)
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -180,6 +180,22 @@ sub feature_pickaxe {
        return ($_[0]);
 }
 
+# checking HEAD file with -e is fragile if the repository was
+# initialized long time ago (i.e. symlink HEAD) and was pack-ref'ed
+# and then pruned.
+sub check_head_link {
+       my ($dir) = @_;
+       my $headfile = "$dir/HEAD";
+       return ((-e $headfile) ||
+               (-l $headfile && readlink($headfile) =~ /^refs\/heads\//));
+}
+
+sub check_export_ok {
+       my ($dir) = @_;
+       return (check_head_link($dir) &&
+               (!$export_ok || -e "$dir/$export_ok"));
+}
+
 # rename detection options for git-diff and git-diff-tree
 # - default is '-M', with the cost proportional to
 #   (number of removed files) * (number of new files).
@@ -212,7 +228,7 @@ our $project = $cgi->param('p');
 if (defined $project) {
        if (!validate_pathname($project) ||
            !(-d "$projectroot/$project") ||
-           !(-e "$projectroot/$project/HEAD") ||
+           !check_head_link("$projectroot/$project") ||
            ($export_ok && !(-e "$projectroot/$project/$export_ok")) ||
            ($strict_export && !project_in_list($project))) {
                undef $project;
@@ -289,7 +305,7 @@ sub evaluate_path_info {
        # find which part of PATH_INFO is project
        $project = $path_info;
        $project =~ s,/+$,,;
-       while ($project && !-e "$projectroot/$project/HEAD") {
+       while ($project && !check_head_link("$projectroot/$project")) {
                $project =~ s,/*[^/]*$,,;
        }
        # validate project
@@ -816,8 +832,7 @@ sub git_get_projects_list {
 
                                my $subdir = substr($File::Find::name, $pfxlen + 1);
                                # we check related file in $projectroot
-                               if (-e "$projectroot/$subdir/HEAD" && (!$export_ok ||
-                                   -e "$projectroot/$subdir/$export_ok")) {
+                               if (check_export_ok("$projectroot/$subdir")) {
                                        push @list, { path => $subdir };
                                        $File::Find::prune = 1;
                                }
@@ -838,8 +853,7 @@ sub git_get_projects_list {
                        if (!defined $path) {
                                next;
                        }
-                       if (-e "$projectroot/$path/HEAD" && (!$export_ok ||
-                           -e "$projectroot/$path/$export_ok")) {
+                       if (check_export_ok("$projectroot/$path")) {
                                my $pr = {
                                        path => $path,
                                        owner => decode("utf8", $owner, Encode::FB_DEFAULT),