[sudo-workers] segfault when #include directive is used in cycles

[Todd C. Miller]

Here's a better fix for the double fclose().

 - todd

diff -r 8900bccef219 toke.l
--- a/toke.l	Tue Feb 09 08:28:03 2010 -0500
+++ b/toke.l	Tue Feb 09 10:36:45 2010 -0500
@@ -840,7 +840,7 @@
 	    efree(pl);
 	}
 	efree(istack[idepth].path);
-	if (!istack[idepth].keepopen)
+	if (idepth && !istack[idepth].keepopen)
 	    fclose(istack[idepth].bs->yy_input_file);
 	yy_delete_buffer(istack[idepth].bs);
     }