Avoid trusting the length encoded in the Snapshot if there is an

runtime/lib/isolate.cc

Index: runtime/lib/isolate.cc
===================================================================
--- runtime/lib/isolate.cc	(revision 10993)
+++ runtime/lib/isolate.cc	(working copy)
@@ -42,15 +42,6 @@
 }
 
 
-static uint8_t* SerializeObject(const Instance& obj) {
-  uint8_t* result = NULL;
-  SnapshotWriter writer(Snapshot::kMessage, &result, &allocator);
-  writer.WriteObject(obj.raw());
-  writer.FinalizeBuffer();
-  return result;
-}
-
-
 static void StoreError(Isolate* isolate, const Object& obj) {
   ASSERT(obj.IsError());
   Error& error = Error::Handle();
@@ -144,11 +135,16 @@
   GET_NATIVE_ARGUMENT(Smi, reply_id, arguments->At(1));
   // TODO(iposva): Allow for arbitrary messages to be sent.
   GET_NATIVE_ARGUMENT(Instance, obj, arguments->At(2));
-  uint8_t* data = SerializeObject(obj);
 
+  uint8_t* data = NULL;
+  SnapshotWriter writer(Snapshot::kMessage, &data, &allocator);
+  writer.WriteObject(obj.raw());
+  intptr_t data_len = writer.FinalizeBuffer();

[siva, 2012/08/22 23:30:39]

As discussed offline we could probably get rid of the call to FinalizeBuffer
here and instead set data_len to writer.bytes_written().

[turnidge, 2012/08/23 18:37:57]

Done.

+
   // TODO(turnidge): Throw an exception when the return value is false?
   PortMap::PostMessage(new Message(
-      send_id.Value(), reply_id.Value(), data, Message::kNormalPriority));
+      send_id.Value(), reply_id.Value(), data, data_len,
+      Message::kNormalPriority));
 }