From 3addea51717c68df20eecabab525b1aa8077c1b2 Mon Sep 17 00:00:00 2001
From: eliben <devnull@localhost>
Date: Thu, 22 Sep 2011 13:54:26 +0300
Subject: [PATCH] adding some useful attributes & method to DIE

---
 elftools/dwarf/die.py | 20 +++++++++++++++++++-
 z.py                  |  3 ++-
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/elftools/dwarf/die.py b/elftools/dwarf/die.py
index f4fc2cb..fba5ed2 100644
--- a/elftools/dwarf/die.py
+++ b/elftools/dwarf/die.py
@@ -60,8 +60,18 @@ class DIE(object):
         self.dwarfinfo = self.cu.dwarfinfo # get DWARFInfo context
         self.stream = stream
         self.offset = offset
+        
         self.attributes = OrderedDict()
-        self._parse_DIE()
+        self.tag = None
+        self.has_children = None
+        self.size = 0
+        
+        self._parse_DIE()   
+    
+    def is_null(self):
+        """ Is this a null entry?
+        """
+        return self.tag is None
     
     def _parse_DIE(self):
         """ Parses the DIE info from the section, based on the abbreviation
@@ -76,14 +86,22 @@ class DIE(object):
         #
         abbrev_code = struct_parse(
             structs.Dwarf_uleb128(''), self.stream, self.offset)
+        
+        # This may be a null entry
+        if abbrev_code == 0:
+            self.size = self.stream.tell() - self.offset
+            return
+        
         with preserve_stream_pos(self.stream):
             abbrev_decl = self.cu.get_abbrev_table().get_abbrev(abbrev_code)
+        self.tag = abbrev_decl['tag']
         self.has_children = abbrev_decl.has_children()
         
         # Guided by the attributes listed in the abbreviation declaration, parse
         # values from the stream.
         #
         for name, form in abbrev_decl.iter_attr_specs():
+            print '**', self.stream.tell()
             raw_value = struct_parse(structs.Dwarf_dw_form[form], self.stream)
             value = self._translate_attr_value(form, raw_value)            
             self.attributes[name] = AttributeValue(form, value, raw_value)
diff --git a/z.py b/z.py
index b41b70c..ea7c762 100644
--- a/z.py
+++ b/z.py
@@ -26,7 +26,8 @@ cu = dwarfinfo.get_CU(1)
 print 'CU header', cu.header
 topdie = cu.get_top_DIE()
 
-print topdie.size, topdie.attributes
+print topdie.size, topdie.tag
+print topdie.attributes
 
 #~ print dwarfinfo.structs.Dwarf_abbrev_entry.parse('\x13\x01\x01\x03\x50\x04\x00\x00')
 
-- 
2.30.2