sync/internal_api/public/read_transaction.h

   1 // Copyright 2012 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 SYNC_INTERNAL_API_PUBLIC_READ_TRANSACTION_H_
   6 #define SYNC_INTERNAL_API_PUBLIC_READ_TRANSACTION_H_
   7
   8 #include "base/compiler_specific.h"
   9 #include "sync/base/sync_export.h"
  10 #include "sync/internal_api/public/base_transaction.h"
  11
  12 namespace tracked_objects {
  13 class Location;
  14 }  // namespace tracked_objects
  15
  16 namespace syncer {
  17
  18 struct UserShare;
  19
  20 // Sync API's ReadTransaction is a read-only BaseTransaction.  It wraps
  21 // a syncable::ReadTransaction.
  22 class SYNC_EXPORT ReadTransaction : public BaseTransaction {
  23  public:
  24   // Start a new read-only transaction on the specified repository.
  25   ReadTransaction(const tracked_objects::Location& from_here,
  26                   UserShare* share);
  27
  28   // Resume the middle of a transaction. Will not close transaction.
  29   ReadTransaction(UserShare* share, syncable::BaseTransaction* trans);
  30
  31   virtual ~ReadTransaction();
  32
  33   // BaseTransaction override.
  34   virtual syncable::BaseTransaction* GetWrappedTrans() const OVERRIDE;
  35
  36   // Return |transaction_version| of |type| stored in sync directory's
  37   // persisted info.
  38   int64 GetModelVersion(ModelType type);
  39
  40  private:
  41   void* operator new(size_t size);  // Transaction is meant for stack use only.
  42
  43   // The underlying syncable object which this class wraps.
  44   syncable::BaseTransaction* transaction_;
  45   bool close_transaction_;
  46
  47   DISALLOW_COPY_AND_ASSIGN(ReadTransaction);
  48 };
  49
  50 }  // namespace syncer
  51
  52 #endif  // SYNC_INTERNAL_API_PUBLIC_READ_TRANSACTION_H_