Another stab at the Chromium side of storage events. The WebKit side can be ...

chrome/browser/in_process_webkit/dom_storage_context.h

 // Copyright (c) 2009 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 CHROME_BROWSER_IN_PROCESS_WEBKIT_DOM_STORAGE_CONTEXT_H_
 #define CHROME_BROWSER_IN_PROCESS_WEBKIT_DOM_STORAGE_CONTEXT_H_
 
 #include "base/file_path.h"
 #include "base/hash_tables.h"
+#include "chrome/browser/in_process_webkit/dom_storage_dispatcher_host.h"
 
 class StorageArea;
 class StorageNamespace;
 class WebKitContext;
 
 // This is owned by WebKitContext and is all the dom storage information that's
 // shared by all the ResourceMessageFilter/DOMStorageDispatcherHosts that share
 // the same profile.  The specifics of responsibilities are fairly well
-// documented here and in StorageNamespace and StorageArea.
+// documented here and in StorageNamespace and StorageArea.  Everything is only
+// to be accessed on the WebKit thread unless noted otherwise.
 class DOMStorageContext {
  public:
   explicit DOMStorageContext(WebKitContext* webkit_context);
   ~DOMStorageContext();
 
   // Get the local storage instance.  The pointer is owned by this class.
   StorageNamespace* LocalStorage();
 
   // Get a new session storage namespace (but it's still owned by this class).
   StorageNamespace* NewSessionStorage();
 
   // Allocate a new storage ___ id.
   int64 AllocateStorageAreaId() { return ++last_storage_area_id_; }
   int64 AllocateStorageNamespaceId() { return ++last_storage_namespace_id_; }
 
   // Various storage area methods.  The storage area is owned by one of the
   // namespaces that's owned by this class.
   void RegisterStorageArea(StorageArea* storage_area);
   void UnregisterStorageArea(StorageArea* storage_area);
   StorageArea* GetStorageArea(int64 id);
 
   // Get a namespace from an id.  What's returned is owned by this class.  The
   // caller of GetStorageNamespace must immediately register itself with the
   // returned StorageNamespace.
   void RegisterStorageNamespace(StorageNamespace* storage_namespace);
   void UnregisterStorageNamespace(StorageNamespace* storage_namespace);
   StorageNamespace* GetStorageNamespace(int64 id);
 
+  // Sometimes an event from one DOM storage dispatcher host requires
+  // communication to all of them.
+  typedef base::hash_set<DOMStorageDispatcherHost*> DispatcherHostSet;
+  void RegisterDispatcherHost(DOMStorageDispatcherHost* dispatcher_host);
+  void UnregisterDispatcherHost(DOMStorageDispatcherHost* dispatcher_host);
+  const DispatcherHostSet* GetDispatcherHostSet() const;
+
   // The special ID used for local storage.
   static const int64 kLocalStorageNamespaceId = 0;
 
  private:
   // The last used storage_area_id and storage_namespace_id's.
   static const int64 kFirstStorageAreaId = 1;
   int64 last_storage_area_id_;
   static const int64 kFirstStorageNamespaceId = 1;
   int64 last_storage_namespace_id_;
 
   // We're owned by this WebKit context.  Used while instantiating LocalStorage.
   WebKitContext* webkit_context_;
 
+  // All the DOMStorageDispatcherHosts that are attached to us. ONLY USE ON THE
+  // IO THREAD!
+  DispatcherHostSet dispatcher_host_set_;
+
   // Maps ids to StorageAreas.  We do NOT own these objects.  StorageNamespace
   // (which does own them) will notify us when we should remove the entries.
   typedef base::hash_map<int64, StorageArea*> StorageAreaMap;
   StorageAreaMap storage_area_map_;
 
   // Maps ids to StorageNamespaces.  We own these objects.
   typedef base::hash_map<int64, StorageNamespace*> StorageNamespaceMap;
   StorageNamespaceMap storage_namespace_map_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(DOMStorageContext);
 };
 
 #endif  // CHROME_BROWSER_IN_PROCESS_WEBKIT_DOM_STORAGE_CONTEXT_H_