Line data    Source code

       1             : /*
       2             :  *
       3             :  *
       4             :  * Distributed under the OpenDDS License.
       5             :  * See: http://www.opendds.org/license.html
       6             :  */
       7             : 
       8             : #ifndef OPENDDS_DCPS_DATABLOCKLOCKPOOL_H
       9             : #define OPENDDS_DCPS_DATABLOCKLOCKPOOL_H
      10             : 
      11             : #include "Atomic.h"
      12             : #include "dcps_export.h"
      13             : #include "PoolAllocationBase.h"
      14             : 
      15             : #include <ace/Lock_Adapter_T.h>
      16             : #include <ace/Thread_Mutex.h>
      17             : #include <ace/Containers_T.h>
      18             : 
      19             : /**
      20             :  * @class DataBlockLockPool
      21             :  *
      22             :  * @brief Holds and distributes locks to be used for locking
      23             :  * ACE_Data_Blocks.  Currently it does not require returning the
      24             :  * locks.
      25             :  *
      26             :  * @NOTE: The lock returned is not guaranteed to be unique.
      27             :  *
      28             :  * @NOTE: This class is thread safe.
      29             :  */
      30             : class OpenDDS_Dcps_Export DataBlockLockPool : public OpenDDS::DCPS::PoolAllocationBase {
      31             : public:
      32             :   typedef ACE_Lock_Adapter<ACE_Thread_Mutex> DataBlockLock;
      33             : 
      34           0 :   DataBlockLockPool(unsigned long size)
      35           0 :     : pool_(size),
      36           0 :       size_(size),
      37           0 :       iterator_(0)
      38             :   {
      39           0 :   }
      40             : 
      41           0 :   ~DataBlockLockPool() { }
      42             : 
      43           0 :   DataBlockLock * get_lock() {
      44           0 :     const unsigned long index = iterator_++ % size_;
      45           0 :     return &(pool_[index]);
      46             :   }
      47             : 
      48             : private:
      49             :   typedef ACE_Array<DataBlockLock> Pool;
      50             : 
      51             :   Pool pool_;
      52             :   const unsigned long size_;
      53             :   /// Counter used to track which lock to give out next (modulus size_)
      54             :   OpenDDS::DCPS::Atomic<unsigned long> iterator_;
      55             : };
      56             : 
      57             : #endif /* DATABLOCKLOCKPOOL_H  */