OnixS C++ FIX Engine  4.2.0
API Documentation
Semaphore.h
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19 
20 #pragma once
21 
22 #include <OnixS/FIXEngine/ABI.h>
23 
24 namespace OnixS {
25 namespace Threading {
26 /// Limits number of threads that can access shared resource simultaneously.
28 {
29 public:
30  /// Initializes the instance with given value of
31  /// "count". @param count indicates initial "count"
32  /// for semaphore. State of semaphore is signaled
33  /// when its count is greater than zero and
34  /// non-signaled when it is zero.
35  Semaphore(unsigned int count = 1);
36 
37  /// Destructs the object.
38  ~Semaphore();
39 
40  /// Decrements semaphore "counter" by one.
41  /// If semaphore "counter" is already zero,
42  /// blocks the thread until semaphore "count"
43  /// becomes greater than zero.
44  void acquire();
45 
46  /// Tries to acquire semaphore object. If
47  /// its "counter" is already zero, returns
48  /// @c false. In all cases, it doesn't block
49  /// the thread and quites immediately.
50  bool tryAcquire();
51 
52  /// Increments semaphore "counter" by one.
53  /// If there are other threads waiting for
54  /// the object, it blocks one the them.
55  void release();
56 
57 private:
58  // Implementation details.
59  void * impl_;
60 
61  // Copying & assignment is prohibited.
62 
63  Semaphore(const Semaphore &);
64  Semaphore & operator = (const Semaphore &);
65 };
66 }
67 }
#define ONIXS_FIXENGINE_API
Definition: ABI.h:45
Limits number of threads that can access shared resource simultaneously.
Definition: Semaphore.h:27