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// Copyright 2015 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 COMPONENTS_CRYPTAUTH_BLUETOOTH_THROTTLER_IMPL_H_
#define COMPONENTS_CRYPTAUTH_BLUETOOTH_THROTTLER_IMPL_H_
#include <memory>
#include <set>
#include "base/macros.h"
#include "base/time/time.h"
#include "components/cryptauth/bluetooth_throttler.h"
#include "components/cryptauth/connection_observer.h"
namespace base {
class TickClock;
}
namespace cryptauth {
class Connection;
// This class throttles repeated connection attempts to the same device. This
// throttling is necessary to prevent a kernel race condition when connecting
// before the previous connection fully closes, putting the connection in a
// corrupted, and unrecoverable state. http://crbug.com/345232
class BluetoothThrottlerImpl : public BluetoothThrottler,
public ConnectionObserver {
public:
// Creates a throttler for connections to a remote device, using the |clock|
// as a time source.
explicit BluetoothThrottlerImpl(std::unique_ptr<base::TickClock> clock);
~BluetoothThrottlerImpl() override;
// BluetoothThrottler:
base::TimeDelta GetDelay() const override;
void OnConnection(Connection* connection) override;
protected:
// Returns the duration to wait, after disconnecting, before reattempting a
// connection to the remote device. Exposed for testing.
base::TimeDelta GetCooldownTimeDelta() const;
private:
// ConnectionObserver:
void OnConnectionStatusChanged(Connection* connection,
Connection::Status old_status,
Connection::Status new_status) override;
// Tracks the last seen disconnect time for the |remote_device_|.
base::TimeTicks last_disconnect_time_;
// The time source.
std::unique_ptr<base::TickClock> clock_;
// The currently connected connections.
// Each connection is stored as a weak reference, which is safe because |this|
// instance is registered as an observer, and will unregister when the
// connection disconnects, which is guaranteed to occur before the connection
// is destroyed.
std::set<Connection*> connections_;
DISALLOW_COPY_AND_ASSIGN(BluetoothThrottlerImpl);
};
} // namespace cryptauth
#endif // COMPONENTS_CRYPTAUTH_BLUETOOTH_THROTTLER_IMPL_H_
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