fixing a few tar issues - and using gnu tar only

lib/gitlab/import_export/command_line_util.rb

@@ -5,12 +5,12 @@ module Gitlab
         tar_with_options(archive: archive, dir: dir, options: 'cf')
       end
 
-      def untar_czf(archive:, dir:)
-        tar_with_options(archive: archive, dir: dir, options: 'czf')
+      def untar_zxf(archive:, dir:)
+        untar_with_options(archive: archive, dir: dir, options: 'zxf')
       end
 
-      def untar_cf(archive:, dir:)
-        tar_with_options(archive: archive, dir: dir, options: 'cf')
+      def untar_czf(archive:, dir:)
+        untar_with_options(archive: archive, dir: dir, options: 'xf')
       end
 
       def tar_czf(archive:, dir:)
@@ -28,6 +28,12 @@ module Gitlab
         _output, status = Gitlab::Popen.popen(cmd)
         status.zero?
       end
+
+      def untar_with_options(archive:, dir:, options:)
+        cmd = %W(tar -#{options} #{archive} -C #{dir})
+        _output, status = Gitlab::Popen.popen(cmd)
+        status.zero?
+      end
     end
   end
 end

lib/gitlab/import_export/importer.rb

@@ -20,7 +20,7 @@ module Gitlab
       private
 
       def decompress_archive
-        untar_czf(archive: @archive_file, dir: @storage_path)
+        untar_zxf(archive: @archive_file, dir: @storage_path)
       end
     end
   end

lib/gitlab/import_export/repo_restorer.rb

@@ -14,7 +14,7 @@ module Gitlab
 
         FileUtils.mkdir_p(repos_path)
         FileUtils.mkdir_p(path_to_repo)
-        untar_cf(archive: @path, dir: path_to_repo)
+        untar_czf(archive: @path, dir: path_to_repo)
       end
 
       private