add util::array_queue

src/util/array_queue.hpp

@@ -0,0 +1,76 @@
+#pragma once
+
+#include <memory>
+#include <cstring>
+#include <stdexcept>
+
+namespace util {
+    template <typename T>
+    class array_queue {
+    public:
+        array_queue(size_t initCapacity = 8)
+        : _capacity(initCapacity),
+            _size(0),
+            _front(0),
+            _back(0),
+            _data(new T[_capacity]) {
+            if (initCapacity == 0 || (initCapacity & (initCapacity - 1)) != 0) {
+                throw std::invalid_argument("initCapacity must be positive power of 2");
+            }
+        }
+
+        ~array_queue() {
+            // todo
+            delete[] _data;
+        }
+
+        void push(T&& value) {
+            if (_back == _front && _size) {
+                grow();
+            }
+            _data[_back] = std::forward<T>(value);
+            _back = (_back + 1) & (_capacity - 1);
+            ++_size;
+        }
+
+        T& front() {
+            return _data[_front];
+        }
+
+        void pop() {
+            _data[_front].~T();
+            _front = (_front + 1) & (_capacity - 1);
+            --_size;
+        }
+
+        bool empty() const {
+            return _size == 0;
+        }
+
+        size_t size() const {
+            return _size;
+        }
+
+    private:
+        size_t _capacity;
+        size_t _size;
+        size_t _front;
+        size_t _back;
+        T* _data;
+
+        void grow() {
+            size_t newCapacity = _capacity * 2;
+            T* newData = new T[newCapacity];
+
+            std::move(_data + _front, _data + _capacity, newData);
+            std::move(_data, _data + _front, newData + (_capacity - _front));
+
+            _back = _size;
+            _front = 0;
+
+            delete[] _data;
+            _data = newData;
+            _capacity = newCapacity;
+        }
+    };
+}