content/browser/indexed_db/indexed_db_transaction_coordinator.h

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_TRANSACTION_COORDINATOR_H_
   6 #define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_TRANSACTION_COORDINATOR_H_
   7
   8 #include <map>
   9 #include <set>
  10 #include <vector>
  11
  12 #include "base/memory/ref_counted.h"
  13 #include "base/memory/scoped_ptr.h"
  14 #include "content/browser/indexed_db/list_set.h"
  15
  16 namespace content {
  17
  18 class IndexedDBTransaction;
  19
  20 // Transactions are executed in the order the were created.
  21 class IndexedDBTransactionCoordinator {
  22  public:
  23   IndexedDBTransactionCoordinator();
  24   ~IndexedDBTransactionCoordinator();
  25
  26   // Called by transactions as they start and finish.
  27   void DidCreateTransaction(scoped_refptr<IndexedDBTransaction> transaction);
  28   void DidFinishTransaction(IndexedDBTransaction* transaction);
  29
  30   bool IsRunningVersionChangeTransaction() const;
  31
  32 #ifndef NDEBUG
  33   bool IsActive(IndexedDBTransaction* transaction);
  34 #endif
  35
  36   // Makes a snapshot of the transaction queue. For diagnostics only.
  37   std::vector<const IndexedDBTransaction*> GetTransactions() const;
  38
  39  private:
  40   typedef list_set<scoped_refptr<IndexedDBTransaction> > TransactionSet;
  41
  42   void ProcessQueuedTransactions();
  43   bool CanStartTransaction(IndexedDBTransaction* const transaction,
  44                            const std::set<int64>& locked_scope) const;
  45
  46   // Transactions in different states are grouped below.
  47   // list_set is used to provide stable ordering; required by spec
  48   // for the queue, convenience for diagnostics for the rest.
  49   TransactionSet queued_transactions_;
  50   TransactionSet started_transactions_;
  51
  52   DISALLOW_COPY_AND_ASSIGN(IndexedDBTransactionCoordinator);
  53 };
  54
  55 }  // namespace content
  56
  57 #endif  // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_TRANSACTION_COORDINATOR_H_