Allocate a Dart_CMessage structure when decoding a message into C structures

runtime/vm/snapshot.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/snapshot.h"
 
 #include "platform/assert.h"
 #include "vm/bootstrap.h"
 #include "vm/exceptions.h"
 #include "vm/heap.h"
@@ skipping 437 matching lines @@
   // updated.
   memset(&type_arguments_marker, 0, sizeof(type_arguments_marker));
   memset(&dynamic_type_marker, 0, sizeof(dynamic_type_marker));
   type_arguments_marker.type =
       static_cast<Dart_CObject::Type>(Dart_CObject_Internal::kTypeArguments);
   dynamic_type_marker.type =
       static_cast<Dart_CObject::Type>(Dart_CObject_Internal::kDynamicType);
 }
 
 
+Dart_CMessage* CMessageReader::ReadMessage() {
+  // Read the object out of the message.
+  Dart_CObject* object = ReadObject();
+
+  Dart_CMessage* message =
+      reinterpret_cast<Dart_CMessage*>(alloc_(NULL, 0, sizeof(Dart_CMessage)));
+  if (message == NULL) return NULL;
+  message->root = object;
+  return message;
+}
+
 intptr_t CMessageReader::LookupInternalClass(intptr_t class_header) {
   SerializedHeaderType header_type = SerializedHeaderTag::decode(class_header);
   ASSERT(header_type == kObjectId);
   intptr_t header_value = SerializedHeaderData::decode(class_header);
   return header_value;
 }
 
 
 Dart_CObject* CMessageReader::AllocateDartCObject(Dart_CObject::Type type) {
   Dart_CObject* value =
@@ skipping 427 matching lines @@
 
 
 void SnapshotWriterVisitor::VisitPointers(RawObject** first, RawObject** last) {
   for (RawObject** current = first; current <= last; current++) {
     RawObject* raw_obj = *current;
     writer_->WriteObject(raw_obj);
   }
 }
 
 }  // namespace dart