mwsr_queue.h
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00034 
00035 #ifndef ROSRT_DETAIL_MWSR_QUEUE_H
00036 #define ROSRT_DETAIL_MWSR_QUEUE_H
00037 
00038 #include "lockfree/object_pool.h"
00039 #include <ros/atomic.h>
00040 
00041 namespace rosrt
00042 {
00043 namespace detail
00044 {
00045 
00046 template<typename T>
00047 class MWSRQueue
00048 {
00049 public:
00050   struct Node
00051   {
00052     T val;
00053     Node* next;
00054   };
00055 
00056   MWSRQueue(uint32_t size)
00057   : pool_(size, Node())
00058   , head_(0)
00059   {
00060 
00061   }
00062 
00063   bool push(const T& val)
00064   {
00065     Node* n = pool_.allocate();
00066     if (!n)
00067     {
00068       return false;
00069     }
00070 
00071     n->val = val;
00072     Node* stale_head = head_.load(ros::memory_order_relaxed);
00073     do
00074     {
00075       n->next = stale_head;
00076     } while(!head_.compare_exchange_weak(stale_head, n, ros::memory_order_release));
00077 
00078     return true;
00079   }
00080 
00081   Node* popAll()
00082   {
00083     Node* last = head_.exchange(0, ros::memory_order_consume);
00084     Node* first = 0;
00085 
00086     // Reverse the list to get it back in push() order
00087     while (last)
00088     {
00089       Node* tmp = last;
00090       last = last->next;
00091       tmp->next = first;
00092       first = tmp;
00093     }
00094 
00095     return first;
00096   }
00097 
00098   void free(Node* node)
00099   {
00100     pool_.free(node);
00101   }
00102 
00103 private:
00104   lockfree::ObjectPool<Node> pool_;
00105   ros::atomic<Node*> head_;
00106 };
00107 
00108 } // namespace detail
00109 } // namespace rosrt
00110 
00111 #endif // ROSRT_DETAIL_MWSR_QUEUE_H


rosrt
Author(s): Josh Faust
autogenerated on Sat Dec 28 2013 17:34:37