30 lines
697 B
C++
30 lines
697 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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private:
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struct node {
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std::shared_ptr<T> data;
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node* next;
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node(T const& data_) : data(std::make_shared<T>(data_)) {}
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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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}
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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 && !head.compare_exchange_weak(old_head, old_head->next))
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;
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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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