A proposal and implementation for an initial postMessage interface. These in...

ppapi/cpp/instance.h

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef PPAPI_CPP_INSTANCE_H_
 #define PPAPI_CPP_INSTANCE_H_
 
 /**
  * @file
  * Defines the API ...
@@ skipping 78 matching lines @@
   bool BindGraphics(const Graphics2D& graphics);
 
   /** See PPB_Instance.BindGraphics. */
   bool BindGraphics(const Surface3D_Dev& graphics);
 
   /** See PPB_Instance.IsFullFrame. */
   bool IsFullFrame();
 
   /** See PPB_Instance.ExecuteScript. */
   Var ExecuteScript(const Var& script, Var* exception = NULL);
+
+  // These functions use the PPP_Messaging and PPB_Messaging interfaces, so that
+  // messaging can be done conveniently for a pp::Instance without using a
+  // separate C++ class.
+
+  /** See PPP_Messaging.HandleMessage. */
+  virtual void HandleMessage(const Var& message_data);

[polina, 2011/03/24 05:42:33]

Seeing "message_data" next to "message" in this section is confusing. If I post
a message to JS handler that just echos it back, then HandleMessage will get the
message in the exact same format. And this does not match the C API. Please
rename.

[dmichael(do not use this one), 2011/03/25 20:21:05]

Good point.  Renamed in:  http://codereview.chromium.org/6748006

+  /** See PPB_Messaging.PostMessage. */
+  void PostMessage(const Var& message);
+
   // @}
 
   /**
    * Associates a plugin instance with an interface,
    * creating an object... {PENDING: clarify!}
    *
    * Many optional interfaces are associated with a plugin instance. For
    * example, the find in PPP_Find interface receives updates on a per-instance
    * basis. This "per-instance" tracking allows such objects to associate
    * themselves with an instance as "the" handler for that interface name.
@@ skipping 41 matching lines @@
   InterfaceNameToObjectMap interface_name_to_objects_;
 };
 
 }  // namespace pp
 
 /**
  * @}
  * End addtogroup CPP
  */
 #endif  // PPAPI_CPP_INSTANCE_H_