Adding Chromium's database tracker.

webkit/database/database_tracker.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 WEBKIT_DATABASE_DATABASE_TRACKER_H_
+#define WEBKIT_DATABASE_DATABASE_TRACKER_H_
+
+#include <map>
+
+#include "base/file_path.h"
+#include "base/observer_list.h"
+#include "base/ref_counted.h"
+#include "base/scoped_ptr.h"
+#include "base/string16.h"
+#include "testing/gtest/include/gtest/gtest_prod.h"
+
+namespace sql {
+class Connection;
+class MetaTable;
+}
+
+namespace webkit_database {
+
+class DatabasesTable;
+
+// This class manages the main database, and keeps track of per origin quotas.
+//
+// The data in this class is not thread-safe, so all methods of this class
+// should be called on the same thread. The only exception is
+// database_directory() which returns a constant that is initialized when
+// the DatabaseTracker instance is created.
+//
+// Furthermore, some methods of this class have to read/write data from/to
+// the disk. Therefore, in a multi-threaded application, all methods of this
+// class should be called on the thread dedicated to file operations (file
+// thread in the browser process, for example), if such a thread exists.
+class DatabaseTracker
+    : public base::RefCountedThreadSafe<DatabaseTracker> {
+ public:
+  class Observer {
+   public:
+    virtual void OnDatabaseSizeChanged(const string16& origin_identifier,
+                                       const string16& database_name,
+                                       int64 database_size,
+                                       int64 space_available) = 0;
+    virtual ~Observer() {}
+  };
+
+  explicit DatabaseTracker(const FilePath& profile_path);
+  ~DatabaseTracker();
+
+  void DatabaseOpened(const string16& origin_identifier,
+                      const string16& database_name,
+                      const string16& database_details,
+                      int64 estimated_size,
+                      int64* database_size,
+                      int64* space_available);
+  void DatabaseModified(const string16& origin_identifier,
+                        const string16& database_name);
+  void DatabaseClosed(const string16& origin_identifier,
+                      const string16& database_name);
+
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+  void CloseTrackerDatabaseAndClearCaches();
+
+  const FilePath& DatabaseDirectory() const { return db_dir_; }
+  FilePath GetFullDBFilePath(const string16& origin_identifier,
+                             const string16& database_name) const;
+
+ private:
+  class CachedOriginInfo {
+   public:
+    CachedOriginInfo() : total_size_(0) { }
+    int64 TotalSize() const { return total_size_; }
+    int64 GetCachedDatabaseSize(const string16& database_name) {
+      return cached_database_sizes_[database_name];
+    }
+    void SetCachedDatabaseSize(const string16& database_name, int64 new_size) {
+      int64 old_size = cached_database_sizes_[database_name];
+      cached_database_sizes_[database_name] = new_size;
+      if (new_size != old_size)
+        total_size_ += new_size - old_size;
+    }
+
+   private:
+    int64 total_size_;
+    std::map<string16, int64> cached_database_sizes_;
+  };
+
+  bool LazyInit();
+  void InsertOrUpdateDatabaseDetails(const string16& origin_identifier,
+                                     const string16& database_name,
+                                     const string16& database_details,
+                                     int64 estimated_size);
+
+  void ClearAllCachedOriginInfo();
+  CachedOriginInfo* GetCachedOriginInfo(const string16& origin_identifier);
+  int64 GetCachedDatabaseFileSize(const string16& origin_identifier,
+                                  const string16& database_name);
+  int64 UpdateCachedDatabaseFileSize(const string16& origin_identifier,
+                                     const string16& database_name);
+  int64 GetDBFileSize(const string16& origin_identifier,
+                      const string16& database_name) const;
+  int64 GetOriginUsage(const string16& origin_identifer);
+  int64 GetOriginQuota(const string16& origin_identifier) const;
+  int64 GetOriginSpaceAvailable(const string16& origin_identifier);
+
+  bool initialized_;
+  const FilePath db_dir_;
+  scoped_ptr<sql::Connection> db_;
+  scoped_ptr<DatabasesTable> databases_table_;
+  scoped_ptr<sql::MetaTable> meta_table_;
+  ObserverList<Observer> observers_;
+  std::map<string16, CachedOriginInfo> origins_info_map_;
+
+  FRIEND_TEST(DatabaseTrackerTest, TestIt);
+};
+
+}  // namespace webkit_database
+
+#endif  // WEBKIT_DATABASE_DATABASE_TRACKER_H_