Migrate the IndexedDB backend from Blink to Chromium

content/browser/indexed_db/indexed_db_transaction_coordinator.h

+// Copyright (c) 2013 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 CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_TRANSACTION_COORDINATOR_H_
+#define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_TRANSACTION_COORDINATOR_H_
+
+#include <map>
+#include <set>
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "content/browser/indexed_db/list_set.h"
+
+namespace content {
+
+class IndexedDBTransaction;
+
+// Transactions are executed in the order the were created.
+class IndexedDBTransactionCoordinator {
+ public:
+  IndexedDBTransactionCoordinator();
+  ~IndexedDBTransactionCoordinator();
+
+  // Called by transactions as they start and finish.
+  void DidCreateTransaction(IndexedDBTransaction* transaction);
+  void DidStartTransaction(IndexedDBTransaction* transaction);
+  void DidFinishTransaction(IndexedDBTransaction* transaction);
+
+#ifndef NDEBUG
+  bool IsActive(IndexedDBTransaction* transaction);
+#endif
+
+  // TODO(jsbell): API to handle closed connections. http://crbug.com/241821
+
+ private:
+  void ProcessStartedTransactions();
+  bool CanRunTransaction(IndexedDBTransaction* transaction);
+
+  // This is just an efficient way to keep references to all transactions.
+  std::map<IndexedDBTransaction*, scoped_refptr<IndexedDBTransaction> >
+      transactions_;
+  // Transactions in different states are grouped below.
+  list_set<IndexedDBTransaction*> queued_transactions_;
+  std::set<IndexedDBTransaction*> started_transactions_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_TRANSACTION_COORDINATOR_H_