Persist sessionStorage on disk.

webkit/dom_storage/dom_storage_area.h

 // Copyright (c) 2012 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_DOM_STORAGE_DOM_STORAGE_AREA_H_
 #define WEBKIT_DOM_STORAGE_DOM_STORAGE_AREA_H_
 #pragma once
 
 #include "base/file_path.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/nullable_string16.h"
 #include "base/string16.h"
 #include "googleurl/src/gurl.h"
-#include "webkit/dom_storage/dom_storage_database.h"
+#include "webkit/dom_storage/dom_storage_database_adapter.h"
 #include "webkit/dom_storage/dom_storage_types.h"
 
 namespace dom_storage {
 
+class DomStorageDatabaseAdapter;
 class DomStorageMap;
 class DomStorageTaskRunner;
+class SessionStorageDatabase;
 
 // Container for a per-origin Map of key/value pairs potentially
 // backed by storage on disk and lazily commits changes to disk.
 // See class comments for DomStorageContext for a larger overview.
 class DomStorageArea
     : public base::RefCountedThreadSafe<DomStorageArea> {
 
  public:
   static const FilePath::CharType kDatabaseFileExtension[];
   static FilePath DatabaseFileNameFromOrigin(const GURL& origin);
   static GURL OriginFromDatabaseFileName(const FilePath& file_name);
 
+  // Local storage. Backed on disk if directory is nonempty.
   DomStorageArea(int64 namespace_id,
                  const GURL& origin,
                  const FilePath& directory,
                  DomStorageTaskRunner* task_runner);
 
+  // Session storage. Backed on disk if |session_storage_backing| is not NULL.
+  DomStorageArea(int64 namespace_id,
+                 const std::string& persistent_namespace_id,
+                 const GURL& origin,
+                 SessionStorageDatabase* session_storage_backing,
+                 DomStorageTaskRunner* task_runner);
+
   const GURL& origin() const { return origin_; }
   int64 namespace_id() const { return namespace_id_; }
 
   // Writes a copy of the current set of values in the area to the |map|.
   void ExtractValues(ValuesMap* map);
 
   unsigned Length();
   NullableString16 Key(unsigned index);
   NullableString16 GetItem(const string16& key);
   bool SetItem(const string16& key, const string16& value,
                NullableString16* old_value);
   bool RemoveItem(const string16& key, string16* old_value);
   bool Clear();
 
-  DomStorageArea* ShallowCopy(int64 destination_namespace_id);
+  DomStorageArea* ShallowCopy(
+      int64 destination_namespace_id,
+      const std::string& destination_persistent_namespace_id);
 
   bool HasUncommittedChanges() const;
 
   // Similar to Clear() but more optimized for just deleting
   // without raising events.
   void DeleteOrigin();
 
   // Frees up memory when possible. Typically, this method returns
   // the object to its just constructed state, however if uncommitted
   // changes are pending, it does nothing.
@@ skipping 33 matching lines @@
   // disk on the commit sequence, and to call back on the primary
   // task sequence when complete.
   CommitBatch* CreateCommitBatchIfNeeded();
   void OnCommitTimer();
   void CommitChanges(const CommitBatch* commit_batch);
   void OnCommitComplete();
 
   void ShutdownInCommitSequence();
 
   int64 namespace_id_;
+  std::string persistent_namespace_id_;
   GURL origin_;
   FilePath directory_;
   scoped_refptr<DomStorageTaskRunner> task_runner_;
   scoped_refptr<DomStorageMap> map_;
-  scoped_ptr<DomStorageDatabase> backing_;
+  scoped_ptr<DomStorageDatabaseAdapter> backing_;
+  scoped_refptr<SessionStorageDatabase> session_storage_backing_;
   bool is_initial_import_done_;
   bool is_shutdown_;
   scoped_ptr<CommitBatch> commit_batch_;
   int commit_batches_in_flight_;
 };
 
 }  // namespace dom_storage
 
 #endif  // WEBKIT_DOM_STORAGE_DOM_STORAGE_AREA_H_