// Copyright 2014 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.
// TransientDeviceIds keep track of transient IDs for removable devices, so
// persistent device IDs are not exposed to renderers. Once a removable device
// gets mapped to a transient ID, the mapping remains valid for the duration of
// TransientDeviceIds' lifetime.
#ifndef COMPONENTS_STORAGE_MONITOR_TRANSIENT_DEVICE_IDS_H_
#define COMPONENTS_STORAGE_MONITOR_TRANSIENT_DEVICE_IDS_H_
#include <map>
#include <string>
#include "base/basictypes.h"
#include "base/threading/thread_checker.h"
namespace storage_monitor {
class TransientDeviceIds {
public:
TransientDeviceIds();
~TransientDeviceIds();
// Returns the transient ID for a given |device_id|.
// |device_id| must be for a fixed or removable storage device.
// If |device_id| has never been seen before, a new, unique transient id will
// be assigned.
std::string GetTransientIdForDeviceId(const std::string& device_id);
// Get the reverse mapping for a transient ID. Returns an empty string if the
// |transient_id| cannot be found.
std::string DeviceIdFromTransientId(const std::string& transient_id) const;
private:
typedef std::map<std::string, std::string> IdMap;
IdMap device_id_map_;
IdMap transient_id_map_;
base::ThreadChecker thread_checker_;
DISALLOW_COPY_AND_ASSIGN(TransientDeviceIds);
};
} // namespace storage_monitor
#endif // COMPONENTS_STORAGE_MONITOR_TRANSIENT_DEVICE_IDS_H_