Drizzled Public API Documentation

observer.h
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30 
31 #include <boost/thread/mutex.hpp>
32 #include <boost/thread/condition_variable.hpp>
33 #include <boost/shared_ptr.hpp>
34 
35 #pragma once
36 
37 namespace user_locks {
38 
39 class Observer {
40 public:
41  typedef boost::shared_ptr<Observer> shared_ptr;
42  typedef std::list <shared_ptr> list;
43 
44  Observer(int64_t wait_until_arg) :
45  woken(false),
46  waiting_for(wait_until_arg)
47  {
48  _mutex.lock();
49  }
50 
51  void sleep()
52  {
53  while (not woken)
54  {
55  cond.wait(_mutex);
56  }
57  _mutex.unlock();
58  }
59 
60  void wake()
61  {
62  {
63  boost::mutex::scoped_lock mutex;
64  woken= true;
65  }
66  cond.notify_all();
67  }
68 
69  ~Observer()
70  {
71  }
72 
73  int64_t getLimit() const
74  {
75  return waiting_for;
76  }
77 
78 private:
79  bool woken;
80  const int64_t waiting_for;
81  boost::mutex _mutex;
82  boost::condition_variable_any cond;
83 };
84 
85 } // namespace user_locks
86