[xsl] most efficient flat file listing to hierarchical

[James Fuller <jim.fuller@xxxxxxxxxxxxxx>]

Hello All,

Can anyone propose a pure xslt (1 or 2) solution to transforming the 
following flat xml structure of directory paths into a hierarchical 
(nested) xml.

<?xml version='1.0'?>
<listing>
   <item>cn/test.xml</item>
   <item>en</item>
   <item>en/test.html</item>
   <item>en/test1.html</item>
   <item>en/resource</item>
   <item>en/resource/style</item>   
   <item>en/resource/style/test.css</item>
   <item>favicon.ico</item>
   <item>cn</item>
</listing>

   to


<dir>
<file name="favicon.ico"/>
<dir name="cn">
   <file name="test.xml"/>
</dir>
<dir name="en">
   <file name="test.html"/>
   <file name="test1.html"/>
   <dir name="resource">
       <dir name="style">
             <file name="test.css"/>
       </dir>
   </dir>
</dir>
</dir>

thx in advance.

cheers, Jim Fuller