Rework service extensions to be safe

runtime/vm/isolate.h

Index: runtime/vm/isolate.h
diff --git a/runtime/vm/isolate.h b/runtime/vm/isolate.h
index e5873ea3150eeb38280716c1b91fc364d9217835..72e399908dc2c9c6bdb1a7a30023a5e18e3466a6 100644
--- a/runtime/vm/isolate.h
+++ b/runtime/vm/isolate.h
@@ -703,6 +703,16 @@ class Isolate : public BaseIsolate {
     compilation_allowed_ = allowed;
   }
 
+  RawObject* InvokePendingExtensionCalls();
+  void AppendExtensionCall(const Instance& closure,
+                           const String& method_name,
+                           const Array& parameter_keys,
+                           const Array& parameter_values,
+                           const Instance& reply_port,
+                           const Instance& id);
+  void RegisterExtensionHandler(const String& name, const Instance& closure);
+  RawInstance* LookupExtensionHandler(const String& name);
+
 #if defined(DEBUG)
 #define REUSABLE_HANDLE_SCOPE_ACCESSORS(object)                                \
   void set_reusable_##object##_handle_scope_active(bool value) {               \
@@ -766,6 +776,16 @@ class Isolate : public BaseIsolate {
     user_tag_ = tag;
   }
 
+  RawGrowableObjectArray* GetAndClearPendingExtensionCalls();
+  RawGrowableObjectArray* pending_extension_calls() const {
+    return pending_extension_calls_;
+  }
+  void set_pending_extension_calls(const GrowableObjectArray& value);
+  RawGrowableObjectArray* registered_extension_handlers() const {
+    return registered_extension_handlers_;
+  }
+  void set_registered_extension_handlers(const GrowableObjectArray& value);
+
   void ClearMutatorThread() {
     mutator_thread_ = NULL;
   }
@@ -857,6 +877,26 @@ class Isolate : public BaseIsolate {
   RawGrowableObjectArray* collected_closures_;
   RawGrowableObjectArray* deoptimized_code_array_;
 
+  // We use 6 list entries for each pending service extension calls.
+  enum {
+    kPendingHandlerIndex = 0,
+    kPendingMethodNameIndex,
+    kPendingKeysIndex,
+    kPendingValuesIndex,
+    kPendingReplyPortIndex,
+    kPendingIdIndex,
+    kPendingEntrySize
+  };
+  RawGrowableObjectArray* pending_extension_calls_;
+
+  // We use 2 list entries for each register extension handler.

[Ivan Posva, 2015/08/26 04:47:00]

register -> registered

[Cutch, 2015/08/26 14:28:00]

Done.

+  enum {
+    kRegisteredNameIndex = 0,
+    kRegisteredHandlerIndex,
+    kRegisteredEntrySize
+  };
+  RawGrowableObjectArray* registered_extension_handlers_;
+
   Metric* metrics_list_head_;
 
   Counters counters_;