xref: /recipes/reactor/s11-s10-TimerQueue.h.diff

 // excerpts from http://code.google.com/p/muduo/
 //
 // Use of this source code is governed by a BSD-style license
 // that can be found in the License file.
 //
 // Author: Shuo Chen (chenshuo at chenshuo dot com)
 
 #ifndef MUDUO_NET_TIMERQUEUE_H
 #define MUDUO_NET_TIMERQUEUE_H
 
 #include <set>
 #include <vector>
 
 #include <boost/noncopyable.hpp>
 
 #include "datetime/Timestamp.h"
 #include "thread/Mutex.h"
 #include "Callbacks.h"
 #include "Channel.h"
 
 namespace muduo
 {
 
 class EventLoop;
 class Timer;
 class TimerId;
 
 ///
 /// A best efforts timer queue.
 /// No guarantee that the callback will be on time.
 ///
 class TimerQueue : boost::noncopyable
 {
  public:
   TimerQueue(EventLoop* loop);
   ~TimerQueue();
 
   ///
   /// Schedules the callback to be run at given time,
   /// repeats if @c interval > 0.0.
   ///
   /// Must be thread safe. Usually be called from other threads.
   TimerId addTimer(const TimerCallback& cb,
                    Timestamp when,
                    double interval);
 
+  void cancel(TimerId timerId);
 
  private:
 
   // FIXME: use unique_ptr<Timer> instead of raw pointers.
   typedef std::pair<Timestamp, Timer*> Entry;
   typedef std::set<Entry> TimerList;
+  typedef std::pair<Timer*, int64_t> ActiveTimer;
+  typedef std::set<ActiveTimer> ActiveTimerSet;
 
   void addTimerInLoop(Timer* timer);
+  void cancelInLoop(TimerId timerId);
   // called when timerfd alarms
   void handleRead();
   // move out all expired timers
   std::vector<Entry> getExpired(Timestamp now);
   void reset(const std::vector<Entry>& expired, Timestamp now);
 
   bool insert(Timer* timer);
 
   EventLoop* loop_;
   const int timerfd_;
   Channel timerfdChannel_;
   // Timer list sorted by expiration
   TimerList timers_;
+
+  // for cancel()
+  bool callingExpiredTimers_; /* atomic */
+  ActiveTimerSet activeTimers_;
+  ActiveTimerSet cancelingTimers_;
 };
 
 }
 #endif  // MUDUO_NET_TIMERQUEUE_H