65 lines
1.2 KiB
C++
65 lines
1.2 KiB
C++
#include <exception>
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#include <memory>
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#include <mutex>
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#include <stack>
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struct empty_stack : std::exception {
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const char* what() const throw() { return "empty stack"; }
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};
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template <typename T>
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class threadsafe_stack {
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private:
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std::stack<T> data;
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mutable std::mutex m;
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public:
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threadsafe_stack() {}
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threadsafe_stack(const threadsafe_stack& other)
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{
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std::lock_guard<std::mutex> lock(other.m);
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data = other.data;
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}
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threadsafe_stack& operator=(const threadsafe_stack&) = delete;
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void push(T new_value)
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{
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std::lock_guard<std::mutex> lock(m);
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data.push(new_value);
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}
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std::shared_ptr<T> pop()
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{
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std::lock_guard<std::mutex> lock(m);
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if (data.empty())
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throw empty_stack();
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std::shared_ptr<T> const res(std::make_shared<T>(data.top()));
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data.pop();
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return res;
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}
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void pop(T& value)
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{
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std::lock_guard<std::mutex> lock(m);
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if (data.empty())
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throw empty_stack();
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value = data.top();
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data.pop();
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}
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bool empty() const
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{
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std::lock_guard<std::mutex> lock(m);
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return data.empty();
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}
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};
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int
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main()
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{
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threadsafe_stack<int> si;
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si.push(5);
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si.pop();
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if (!si.empty()) {
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int x;
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si.pop(x);
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}
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}
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