Drizzled Public API Documentation

observer.h
00001 /* - mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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00004  * Copyright (C) 2010 Brian Aker
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00030 
00031 #include <boost/thread/mutex.hpp>
00032 #include <boost/thread/condition_variable.hpp>
00033 #include <boost/shared_ptr.hpp>
00034 
00035 #pragma once
00036 
00037 namespace user_locks {
00038 
00039 class Observer {
00040 public:
00041   typedef boost::shared_ptr<Observer> shared_ptr;
00042   typedef std::list <shared_ptr> list;
00043 
00044   Observer(int64_t wait_until_arg) :
00045     woken(false),
00046     waiting_for(wait_until_arg)
00047   { 
00048     _mutex.lock();
00049   }
00050 
00051   void sleep()
00052   {
00053     while (not woken)
00054     {
00055       cond.wait(_mutex);
00056     }
00057     _mutex.unlock();
00058   }
00059 
00060   void wake()
00061   {
00062     {
00063       boost::mutex::scoped_lock mutex;
00064       woken= true;
00065     }
00066     cond.notify_all();
00067   }
00068 
00069   ~Observer()
00070   {
00071   }
00072 
00073   int64_t getLimit() const
00074   {
00075     return waiting_for;
00076   }
00077 
00078 private:
00079   bool woken;
00080   const int64_t waiting_for;
00081   boost::mutex _mutex;
00082   boost::condition_variable_any cond;
00083 };
00084 
00085 } // namespace user_locks
00086