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

webkit/plugins/ppapi/ppapi_plugin_instance.h

 // Copyright (c) 2011 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 WEBKIT_PLUGINS_PPAPI_PPAPI_PLUGIN_INSTANCE_H_
 #define WEBKIT_PLUGINS_PPAPI_PPAPI_PLUGIN_INSTANCE_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 11 matching lines @@
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebCanvas.h"
 #include "ui/gfx/rect.h"
 #include "webkit/plugins/ppapi/plugin_delegate.h"
 
 typedef struct NPObject NPObject;
 struct PP_Var;
 struct PPB_Instance;
 struct PPB_Find_Dev;
 struct PPB_Fullscreen_Dev;
+struct PPB_Messaging_Dev;
 struct PPB_Zoom_Dev;
 struct PPP_Find_Dev;
 struct PPP_Instance;
+struct PPP_Messaging_Dev;
 struct PPP_Pdf;
 struct PPP_Selection_Dev;
 struct PPP_Zoom_Dev;
 
 class SkBitmap;
 class TransportDIB;
 
 namespace gfx {
 class Rect;
 }
 
 namespace WebKit {
 struct WebCursorInfo;
 class WebInputEvent;
 class WebPluginContainer;
 }
 
 namespace webkit {
 namespace ppapi {
 
 class FullscreenContainer;
+class MessageChannel;
 class ObjectVar;
 class PluginDelegate;
 class PluginModule;
 class PluginObject;
 class PPB_Graphics2D_Impl;
 class PPB_ImageData_Impl;
 class PPB_Surface3D_Impl;
 class PPB_URLLoader_Impl;
 class Resource;
 
 // Represents one time a plugin appears on one web page.
 //
 // Note: to get from a PP_Instance to a PluginInstance*, use the
 // ResourceTracker.
 class PluginInstance : public base::RefCounted<PluginInstance> {
  public:
   PluginInstance(PluginDelegate* delegate,
                  PluginModule* module,
                  const PPP_Instance* instance_interface);
   ~PluginInstance();
 
   static const PPB_Instance* GetInterface();
 
   // Returns a pointer to the interface implementing PPB_Find that is
   // exposed to the plugin.
   static const PPB_Find_Dev* GetFindInterface();
   static const PPB_Fullscreen_Dev* GetFullscreenInterface();
+  static const PPB_Messaging_Dev* GetMessagingInterface();
   static const PPB_Zoom_Dev* GetZoomInterface();
 
   PluginDelegate* delegate() const { return delegate_; }
   PluginModule* module() const { return module_.get(); }
+  MessageChannel& message_channel() { return *message_channel_; }
 
   WebKit::WebPluginContainer* container() const { return container_; }
 
   const gfx::Rect& position() const { return position_; }
   const gfx::Rect& clip() const { return clip_; }
 
   int find_identifier() const { return find_identifier_; }
 
   void set_always_on_top(bool on_top) { always_on_top_ = on_top; }
 
@@ skipping 106 matching lines @@
 
   // Switches between fullscreen and normal mode. If |delay_report| is set to
   // false, it may report the new state through DidChangeView immediately. If
   // true, it will delay it. When called from the plugin, delay_report should be
   // true to avoid re-entrancy.
   void SetFullscreen(bool fullscreen, bool delay_report);
 
   // Implementation of PPB_Flash.
   bool NavigateToURL(const char* url, const char* target);
 
+  // Implementation of PPB_Messaging.

[brettw, 2011/03/22 05:59:11]

I'd just use one comment for both of these functions. I don't think
"Implementation" is too misleading here, even though one of the functions is an
override. If this offends you, sometimes some people just write "//
PPP_Messanging."

+  void PostMessage(PP_Var message);
+  // Passthrough for PPP_Messaging.
+  void HandleMessage(PP_Var message);
+
   PluginDelegate::PlatformContext3D* CreateContext3D();
 
   // Tracks all live ObjectVar. This is so we can map between PluginModule +
   // NPObject and get the ObjectVar corresponding to it. This Add/Remove
   // function should be called by the ObjectVar when it is created and
   // destroyed.
   void AddNPObjectVar(ObjectVar* object_var);
   void RemoveNPObjectVar(ObjectVar* object_var);
 
   // Looks up a previously registered ObjectVar for the given NPObject and
   // module. Returns NULL if there is no ObjectVar corresponding to the given
   // NPObject for the given module. See AddNPObjectVar above.
   ObjectVar* ObjectVarForNPObject(NPObject* np_object) const;
 
   // Returns true iff the plugin is a full-page plugin (i.e. not in an iframe or
   // embedded in a page).
   bool IsFullPagePlugin() const;
 
  private:
   bool LoadFindInterface();
+  bool LoadMessagingInterface();
   bool LoadPdfInterface();
   bool LoadSelectionInterface();
   bool LoadZoomInterface();
 
   // Determines if we think the plugin has focus, both content area and webkit
   // (see has_webkit_focus_ below).
   bool PluginHasFocus() const;
 
   // Reports the current plugin geometry to the plugin by calling
   // DidChangeView.
@@ skipping 65 matching lines @@
   // tab/window has focus. We tell the plugin it has focus only when both of
   // these values are set to true.
   bool has_webkit_focus_;
   bool has_content_area_focus_;
 
   // The id of the current find operation, or -1 if none is in process.
   int find_identifier_;
 
   // The plugin-provided interfaces.
   const PPP_Find_Dev* plugin_find_interface_;
+  const PPP_Messaging_Dev* plugin_messaging_interface_;
   const PPP_Pdf* plugin_pdf_interface_;
   const PPP_Selection_Dev* plugin_selection_interface_;
   const PPP_Zoom_Dev* plugin_zoom_interface_;
 
   // This is only valid between a successful PrintBegin call and a PrintEnd
   // call.
   PP_PrintSettings_Dev current_print_settings_;
 #if defined(OS_MACOSX)
   // On the Mac, when we draw the bitmap to the PDFContext, it seems necessary
   // to keep the pixels valid until CGContextEndPage is called. We use this
@@ skipping 28 matching lines @@
   bool always_on_top_;
 
   // Plugin container for fullscreen mode. NULL if not in fullscreen mode. Note:
   // there is a transition state where fullscreen_container_ is non-NULL but
   // fullscreen_ is false (see above).
   FullscreenContainer* fullscreen_container_;
 
   // True if we are in fullscreen mode. Note: it is false during the transition.
   bool fullscreen_;
 
+  // The MessageChannel used to implement bidirectional postMessage for the
+  // instance.
+  scoped_ptr<MessageChannel> message_channel_;
+
   // Bitmap for crashed plugin. Lazily initialized, non-owning pointer.
   SkBitmap* sad_plugin_;
 
   typedef std::set<PluginObject*> PluginObjectSet;
   PluginObjectSet live_plugin_objects_;
 
   // Tracks all live ObjectVars used by this module so we can map NPObjects to
   // the corresponding object. These are non-owning references.
   typedef std::map<NPObject*, ObjectVar*> NPObjectToObjectVarMap;
   NPObjectToObjectVarMap np_object_to_object_var_;
 
   DISALLOW_COPY_AND_ASSIGN(PluginInstance);
 };
 
 }  // namespace ppapi
 }  // namespace webkit
 
 #endif  // WEBKIT_PLUGINS_PPAPI_PPAPI_PLUGIN_INSTANCE_H_