Trying to improve print output when stubborn call fails

Author: hakril

tests/test_orpc.py

@@ -16,7 +16,14 @@
 #   A second check about in parameters can be done with put_Left / get_Left or put_Visible
 def test_orpc_iexplore():
     iid = gdef.IWebBrowser2.IID
-    client, ipid = windows.rpc.stubborn.stubborn_create_instance("0002DF01-0000-0000-C000-000000000046", iid)
+    try:
+        client, ipid = windows.rpc.stubborn.stubborn_create_instance("0002DF01-0000-0000-C000-000000000046", iid)
+    except Exception as e:
+        dbginfo = getattr(e, "stubborn_info", None)
+        if dbginfo:
+            for x in dbginfo.items():
+                print(x)
+        raise
 
     # get_FullName
     addrep = client.call(iid, 38, b"", ipid=ipid)
@@ -45,7 +52,14 @@ def test_orpc_iexplore():
 def test_orpc_network_manager():
     """ORPC: Testing ORPCTHAT size using a method that takes no arguments and returns a single bytes"""
     iid = gdef.GUID.from_string("D0074FFD-570F-4A9B-8D69-199FDBA5723B")
-    client, ipid = windows.rpc.stubborn.stubborn_create_instance("A47979D2-C419-11D9-A5B4-001185AD2B89", iid)
+    try:
+        client, ipid = windows.rpc.stubborn.stubborn_create_instance("A47979D2-C419-11D9-A5B4-001185AD2B89", iid)
+    except Exception as e:
+        dbginfo = getattr(e, "stubborn_info", None)
+        if dbginfo:
+            for x in dbginfo.items():
+                print(x)
+        raise
     response = client.call(iid, 17, b"", ipid=ipid)
     assert response[0] not in (b"\x00", 0)
 

windows/rpc/stubborn.py

@@ -73,7 +73,18 @@ def stubborn_create_instance(clsid, iid):
             # Bad alignement for everythin -> Legacy
             resolver_info = ctypes.cast(rpiv_infoptr, gdef.PPRIV_RESOLVER_INFO_LEGACY)[0]
 
-    psa = resolver_info.OxidInfo.psa[0] # Retrieve the bidings to our COM server
+    try:
+        psa = resolver_info.OxidInfo.psa[0] # Retrieve the bidings to our COM server
+    except ValueError as e:
+        # Seen case of NULL DEREF
+        # Embed more value to the except for better debugging
+        e.stubborn_info = {
+            "resolver_info.OxidInfo.containerVersion.version": resolver_info.OxidInfo.containerVersion.version,
+            "dcomversion": (dcomversionstruct.MajorVersion, dcomversionstruct.MinorVersion),
+            "resolver_info": resolver_info,
+        }
+        raise
+
     # print("psa.bidings: {0}".format(psa.bidings))
     # ipidRemUnknown = resolver_info.OxidInfo.ipidRemUnknown # Useful for IRemQueryInterface