Contributed by EiNSTeiN_:

- Fixed compilation error on Linux
- Minor bugfix in hexrays.i
- Added two more samples: vds3.py and vds_xrefs.py

Author: elias.bachaalany@gmail.com

examples/vds3.py

@@ -0,0 +1,162 @@
+""" Invert the then and else blocks of a cif_t.
+
+Author: EiNSTeiN_ <einstein@g3nius.org>
+
+This is a rewrite in Python of the vds3 example that comes with hexrays sdk.
+
+
+The main difference with the original C code is that when we create the inverted 
+condition object, the newly created cexpr_t instance is given to the hexrays and 
+must not be freed by swig. To achieve this, we have to change the 'thisown' flag 
+when appropriate. See http://www.swig.org/Doc1.3/Python.html#Python_nn35
+
+"""
+
+import idautils
+import idaapi
+import idc
+
+import traceback
+
+NETNODE_NAME = '$ hexrays-inverted-if'
+
+class hexrays_callback_info(object):
+    
+    def __init__(self):
+        self.vu = None
+        
+        self.node = idaapi.netnode()
+        if not self.node.create(NETNODE_NAME):
+            # node exists
+            self.load()
+        else:
+            self.stored = []
+        
+        return
+    
+    def load(self):
+        
+        self.stored = []
+        
+        try:
+            data = self.node.getblob(0, 'I')
+            if data:
+                self.stored = eval(data)
+                print 'Invert-if: Loaded %s' % (repr(self.stored), )
+        except:
+            print 'Failed to load invert-if locations'
+            traceback.print_exc()
+            return
+        
+        return
+    
+    def save(self):
+        
+        try:
+            self.node.setblob(repr(self.stored), 0, 'I')
+        except:
+            print 'Failed to save invert-if locations'
+            traceback.print_exc()
+            return
+        
+        return
+    
+    def invert_if(self, cfunc, insn):
+        
+        if insn.opname != 'if':
+            return False
+        
+        cif = insn.details
+        
+        if not cif.ithen or not cif.ielse:
+            return False
+        
+        idaapi.qswap(cif.ithen, cif.ielse)
+        cond = idaapi.cexpr_t(cif.expr)
+        notcond = idaapi.lnot(cond)
+        cond.thisown = 0 # the new wrapper 'notcond' now holds the reference to the cexpr_t
+        
+        cif.expr.swap(notcond)
+        
+        return True
+    
+    def add_location(self, ea):
+        if ea in self.stored:
+            self.stored.remove(ea)
+        else:
+            self.stored.append(ea)
+        self.save()
+        return
+    
+    def invert_if_event(self, vu):
+        
+        vu.get_current_item(idaapi.USE_KEYBOARD)
+        item = vu.item
+        
+        cfunc = vu.cfunc.__deref__()
+        
+        if item.citype != idaapi.VDI_EXPR:
+            return False
+        
+        if self.invert_if(cfunc, item.it.to_specific_type):
+            vu.refresh_ctext()
+            
+            self.add_location(item.it.ea)
+        
+        return True
+    
+    def restore(self, cfunc):
+        
+        #~ print 'restoring invert-if for %x' % (cfunc.entry_ea, )
+        
+        str(cfunc) # generate treeitems.
+        
+        restored = False
+        
+        for item in cfunc.treeitems:
+            item = item.to_specific_type
+            if item.opname == 'if' and item.ea in self.stored:
+                if self.invert_if(cfunc, item):
+                    restored = True
+                    #~ print 'restore invert-if location %x' % (item.ea, )
+                else:
+                    print 'invert-if location %x: NOT RESTORED' % (item.ea, )
+        
+        return restored
+    
+    def menu_callback(self):
+        try:
+            self.invert_if_event(self.vu)
+        except:
+            traceback.print_exc()
+        return 0
+    
+    def event_callback(self, event, *args):
+        
+        try:
+            if event == idaapi.hxe_keyboard:
+                vu, keycode, shift = args
+                
+                if idaapi.lookup_key_code(keycode, shift, True) == idaapi.get_key_code("I") and shift == 0:
+                    if self.invert_if_event(vu):
+                        return 1
+                
+            elif event == idaapi.hxe_right_click:
+                self.vu = args[0]
+                idaapi.add_custom_viewer_popup_item(self.vu.ct, "Invert then/else", "I", self.menu_callback)
+            
+            elif event == idaapi.hxe_maturity:
+                cfunc, maturity = args
+                
+                if maturity == idaapi.CMAT_FINAL:
+                    self.restore(cfunc)
+        except:
+            traceback.print_exc()
+        
+        return 0
+
+if idaapi.init_hexrays_plugin():
+    i = hexrays_callback_info()
+    idaapi.install_hexrays_callback(i.event_callback)
+else:
+    print 'invert-if: hexrays is not available.'