32 lines
758 B
C++
32 lines
758 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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struct node
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{
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std::shared_ptr<T> data;
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node* next;
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node(T const& data_):
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data(std::make_shared<T>(data_))
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{}
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};
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std::atomic<node*> head;
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public:
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void push(T const& data)
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{
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node* const new_node=new node(data);
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new_node->next=head.load();
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while(!head.compare_exchange_weak(new_node->next,new_node));
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}
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std::shared_ptr<T> pop()
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{
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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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return old_head ? old_head->data : std::shared_ptr<T>();
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}
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};
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