OpenWalnut  1.4.0
WSharedObjectTicketWrite.h
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3 // Project: OpenWalnut ( http://www.openwalnut.org )
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24 
25 #ifndef WSHAREDOBJECTTICKETWRITE_H
26 #define WSHAREDOBJECTTICKETWRITE_H
27 
28 #ifndef Q_MOC_RUN
29 #include <boost/shared_ptr.hpp>
30 #endif
31 
32 #include "WCondition.h"
33 #include "WSharedObjectTicket.h"
34 
35 /**
36  * Class which represents granted access to a locked object. It contains a reference to the object and a lock. The lock is freed after the ticket
37  * has been destroyed. This class especially implements the exclusive (write) lock.
38  */
39 template < typename Data >
41 {
42 // the shared object class needs protected access to create new instances
43 friend class WSharedObject< Data >;
44 public:
45  /**
46  * Destroys the ticket and releases the lock.
47  */
49  {
50  // explicitly unlock to ensure the WSharedObjectTicket destructor can call the update callback AFTER the lock has been released
51  unlock();
52  };
53 
54  /**
55  * Returns the protected data. As long as you own the ticket, you are allowed to use it.
56  *
57  * \return the data
58  */
59  Data& get() const
60  {
62  };
63 
64 protected:
65  /**
66  * Create a new instance. It is protected to avoid someone to create them. It locks the mutex for write.
67  *
68  * \param data the data to protect
69  * \param mutex the mutex used to lock
70  * \param condition a condition that should be fired upon unlock. Can be NULL.
71  */
72  WSharedObjectTicketWrite( Data& data, boost::shared_ptr< boost::shared_mutex > mutex, boost::shared_ptr< WCondition > condition ): // NOLINT
73  WSharedObjectTicket< Data >( data, mutex, condition ),
74  m_lock( boost::unique_lock< boost::shared_mutex >( *mutex ) )
75  {
76  };
77 
78  /**
79  * The lock.
80  */
81  boost::unique_lock< boost::shared_mutex > m_lock;
82 
83  /**
84  * Unlocks the mutex.
85  */
86  virtual void unlock()
87  {
88  m_lock.unlock();
89  }
90 
91 private:
92 };
93 
94 #endif // WSHAREDOBJECTTICKETWRITE_H
95 
Class which represents granted access to a locked object.
Wrapper around an object/type for thread safe sharing of objects among multiple threads.
Definition: WSharedObject.h:43
virtual ~WSharedObjectTicketWrite()
Destroys the ticket and releases the lock.
WSharedObjectTicketWrite(Data &data, boost::shared_ptr< boost::shared_mutex > mutex, boost::shared_ptr< WCondition > condition)
Create a new instance.
boost::unique_lock< boost::shared_mutex > m_lock
The lock.
Class which represents granted access to a locked object.
virtual void unlock()
Unlocks the mutex.