RingBuffer

RingBuffer.h

#pragma once

template <bool B, size_t T, size_t F> 
struct binarywrap_t { static const size_t size = T; }; 

template <size_t T, size_t F>
struct binarywrap_t<false, T, F> { static const size_t size = F; }; 

template <size_t n, size_t m = 1>
struct binarywrap { 
	static const size_t size = binarywrap_t<(m < n), binarywrap<n, (m << 1)>::size, m>::size; 
};
template <size_t n>
struct binarywrap<n, 0> { static const size_t size = 1; };

template<typename T, size_t _size>
class RingBuffer
{
public:
	RingBuffer():index_(-1){}
	void add(const T &t) {
		index_ = _next(1);
		buffer_[index_] = t;
	}
	void next(size_t interval=1) {
		index_ = _next(interval);
	}
	T& get(size_t interval) {
		return buffer_[_prev(interval)];
	}
	size_t size() { return SIZE; }
private:
	static const size_t SIZE = binarywrap<_size>::size;
	T buffer_[SIZE];
	size_t index_;
private:
	size_t _next(size_t interval) {
		return (index_+interval)&(SIZE-1);
	}
	size_t _prev(size_t interval) {
		interval &= SIZE-1;
		return (index_-interval+SIZE)&(SIZE-1);
	}
};