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diff --git a/chromium/net/quic/quic_alarm.h b/chromium/net/quic/quic_alarm.h
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+++ b/chromium/net/quic/quic_alarm.h
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+// Copyright 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 NET_QUIC_QUIC_ALARM_H_
+#define NET_QUIC_QUIC_ALARM_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "net/base/net_export.h"
+#include "net/quic/quic_time.h"
+
+namespace net {
+
+// Abstract class which represents an alarm which will go off at a
+// scheduled time, and execute the |OnAlarm| method of the delegate.
+// An alarm may be cancelled, in which case it may or may not be
+// removed from the underlying scheduling system, but in either case
+// the task will not be executed.
+class NET_EXPORT_PRIVATE QuicAlarm {
+ public:
+  class NET_EXPORT_PRIVATE Delegate {
+   public:
+    virtual ~Delegate() {}
+
+    // Invoked when the alarm fires.  If the return value is not
+    // infinite, then the alarm will be rescheduled at the
+    // specified time.
+    virtual QuicTime OnAlarm() = 0;
+  };
+
+  explicit QuicAlarm(Delegate* delegate);
+  virtual ~QuicAlarm();
+
+  // Sets the alarm to fire at |deadline|.  Must not be called while
+  // the alarm is set.  To reschedule an alarm, call Cancel() first,
+  // then Set().
+  void Set(QuicTime deadline);
+
+  // Cancels the alarm.  May be called repeatedly.  Does not
+  // guarantee that the underlying scheduling system will remove
+  // the alarm's associated task, but guarantees that the
+  // delegates OnAlarm method will not be called.
+  void Cancel();
+
+  bool IsSet() const;
+
+  QuicTime deadline() const { return deadline_; }
+
+ protected:
+  // Subclasses implement this method to perform the platform-specific
+  // scheduling of the alarm.  Is called from Set() or Fire(), after the
+  // deadline has been updated.
+  virtual void SetImpl() = 0;
+
+  // Subclasses implement this method to perform the platform-specific
+  // cancelation of the alarm.
+  virtual void CancelImpl() = 0;
+
+  // Called by subclasses when the alarm fires.  Invokes the
+  // delegates |OnAlarm| if a delegate is set, and if the deadline
+  // has been exceeded.  Implementations which do not remove the
+  // alarm from the underlying scheduler on Cancel() may need to handle
+  // the situation where the task executes before the deadline has been
+  // reached, in which case they need to reschedule the task and must not
+  // call invoke this method.
+  void Fire();
+
+ private:
+  scoped_ptr<Delegate> delegate_;
+  QuicTime deadline_;
+
+  DISALLOW_COPY_AND_ASSIGN(QuicAlarm);
+};
+
+}  // namespace net
+
+#endif  // NET_QUIC_QUIC_ALARM_H_