26 lines
567 B
C++
26 lines
567 B
C++
#include <atomic>
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#include <memory>
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template<typename T>
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class lock_free_stack
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{
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private:
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std::atomic<unsigned> threads_in_pop;
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void try_reclaim(node* old_head);
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public:
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std::shared_ptr<T> pop()
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{
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++threads_in_pop;
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node* old_head=head.load();
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while(old_head &&
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!head.compare_exchange_weak(old_head,old_head->next));
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std::shared_ptr<T> res;
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if(old_head)
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{
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res.swap(old_head->data);
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}
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try_reclaim(old_head);
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return res;
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}
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};
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