--- a/paraspace/dex_deptracker.py	Sun Jun 19 21:08:31 2011 +0800
+++ b/paraspace/dex_deptracker.py	Mon Jun 20 13:32:15 2011 +0800
@@ -203,7 +203,14 @@
     pass
 
 
-def _travel_dex_relocatable(root_obj, parents=[]):
+## \brief Travel the tree of relocatable objects and their attributes.
+#
+# \param skip_func is a function that returns true for skip a subtree.
+#
+# \ref skip_func is called for every relocatable and their attributes
+# to determines if visiting the object and subtree.
+#
+def _travel_dex_relocatable(root_obj, parents=[], skip_func=None):
     stk = [(root_obj, parents, root_obj.__class__.__name__)]
     
     def make_travel_info(obj, obj_name, child_name, parents):
@@ -218,6 +225,8 @@
     
     while stk:
         obj, parents, obj_name = stk.pop(0)
+        if skip_func and skip_func(obj, parents, obj_name):
+            continue
         yield (obj, parents, obj_name)
         
         if isinstance(obj, list):
@@ -667,6 +676,41 @@
     pass
 
 
+def _build_depon_dep_map(all_dep_decls):
+    def _build_sub_depon_dep(from_path, dep):
+        depon1 = dep[1]
+        sub = [(depon1, from_path)]
+        dep_type = dep[0]
+        if dep_type == dexfile.depend_off_rel:
+            depon2 = dep[2]
+            sub.append((depon2, from_path))
+            pass
+        
+        return sub
+    
+    depon_dep_lsts = [_build_sub_depon_dep(from_path, dep)
+                      for from_path, dep in all_dep_decls.items()]
+    depon_dep_lst = chain(*depon_dep_lsts)
+    depon_dep_map = dict(depon_dep_lst)
+    pass
+
+
+def update_offset(dexroot, all_dep_decls):
+    depon_dep_map = _build_sub_depon_dep(all_dep_decls)
+
+    def skip_dep(obj, parents, name_path):
+        if name_path in all_dep_decls:
+            return True
+        return False
+    
+    for obj, parents, name_path in \
+            _travel_dex_relocatable(dexroot, skip_func=skip_dep):
+        if name_path not in depon_dep_map:
+            continue
+        pass
+    pass
+
+
 ## \brief Restore to raw value before linking for dependencies.
 #
 def restore_dependencies(dexroot, all_dep_decls):