DomStorage data deletion and memory purging.

webkit/dom_storage/dom_storage_database.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_DATABASE_H_
 #define WEBKIT_DOM_STORAGE_DOM_STORAGE_DATABASE_H_
 #pragma once
 
 #include <map>
 
 #include "base/file_path.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/nullable_string16.h"
 #include "base/string16.h"
 #include "sql/connection.h"
 #include "webkit/dom_storage/dom_storage_types.h"
 
 namespace dom_storage {
 
 // Represents a SQLite based backing for DOM storage data. This
 // class is designed to be used on a single thread.
 class DomStorageDatabase {
  public:
+  static FilePath GetJournalFilePath(const FilePath& database_path);
+
   explicit DomStorageDatabase(const FilePath& file_path);
   virtual ~DomStorageDatabase();  // virtual for unit testing
 
   // Reads all the key, value pairs stored in the database and returns
   // them. |result| is assumed to be empty and any duplicate keys will
   // be overwritten. If the database exists on disk then it will be
   // opened. If it does not exist then it will not be created and
   // |result| will be unmodified.
   void ReadAllValues(ValuesMap* result);
 
   // Updates the backing database. Will remove all keys before updating
   // the database if |clear_all_first| is set. Then all entries in
   // |changes| will be examined - keys mapped to a null NullableString16
   // will be removed and all others will be inserted/updated as appropriate.
   bool CommitChanges(bool clear_all_first, const ValuesMap& changes);
 
+  // Simple getter for the path we were constructed with.
+  const FilePath& file_path() const { return file_path_; }
+
  protected:
   // Constructor that uses an in-memory sqlite database, for testing.
   DomStorageDatabase();
 
  private:
   FRIEND_TEST_ALL_PREFIXES(DomStorageDatabaseTest, SimpleOpenAndClose);
   FRIEND_TEST_ALL_PREFIXES(DomStorageDatabaseTest, TestLazyOpenIsLazy);
   FRIEND_TEST_ALL_PREFIXES(DomStorageDatabaseTest, TestDetectSchemaVersion);
   FRIEND_TEST_ALL_PREFIXES(DomStorageDatabaseTest,
                            TestLazyOpenUpgradesDatabase);
   FRIEND_TEST_ALL_PREFIXES(DomStorageDatabaseTest, SimpleWriteAndReadBack);
   FRIEND_TEST_ALL_PREFIXES(DomStorageDatabaseTest, WriteWithClear);
   FRIEND_TEST_ALL_PREFIXES(DomStorageDatabaseTest,
                            UpgradeFromV1ToV2WithData);
   FRIEND_TEST_ALL_PREFIXES(DomStorageDatabaseTest, TestSimpleRemoveOneValue);
   FRIEND_TEST_ALL_PREFIXES(DomStorageDatabaseTest,
                            TestCanOpenAndReadWebCoreDatabase);
   FRIEND_TEST_ALL_PREFIXES(DomStorageDatabaseTest,
                            TestCanOpenFileThatIsNotADatabase);
   FRIEND_TEST_ALL_PREFIXES(DomStorageAreaTest, BackingDatabaseOpened);
   FRIEND_TEST_ALL_PREFIXES(DomStorageAreaTest, CommitTasks);
+  FRIEND_TEST_ALL_PREFIXES(DomStorageAreaTest, PurgeMemory);
 
   enum SchemaVersion {
     INVALID,
     V1,
     V2
   };
 
   // Open the database at file_path_ if it exists already and creates it if
   // |create_if_needed| is true.
   // Ensures we are at the correct database version and creates or updates
@@ skipping 21 matching lines @@
   // version 2.
   bool UpgradeVersion1To2();
 
   void Close();
   bool IsOpen() const { return db_.get() ? db_->is_open() : false; }
 
   // Initialization code shared between the two constructors of this class.
   void Init();
 
   // Path to the database on disk.
-  FilePath file_path_;
+  const FilePath file_path_;
   scoped_ptr<sql::Connection> db_;
   bool failed_to_open_;
   bool tried_to_recreate_;
   bool known_to_be_empty_;
 };
 
 }  // namespace dom_storage
 
 #endif  // WEBKIT_DOM_STORAGE_DOM_STORAGE_DATABASE_H_