ring_buffer.hpp

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#ifndef DISRUPTORCPP_RING_BUFFER_HPP
#define DISRUPTORCPP_RING_BUFFER_HPP

#include <iostream>
#include <memory>
#include <vector>
#include "common_def.hpp" 
        
////////////////////////////////////////////////////////////////////////////////
template<typename T>
class RingBuffer
{
    public:
        RingBuffer() {
            capacity_ = DEFAULT_RING_BUFFER_SIZE;
            buffer_.reserve(DEFAULT_RING_BUFFER_SIZE);
        }
        RingBuffer(const std::vector<T>& buffer) : buffer_(buffer) {}
        
        T& operator[](const int64_t & sequence) { 
            return buffer_[sequence & (capacity_ - 1)]; //only when multiple of 2
        }
        
        int64_t GetTranslatedIndex( int64_t sequence) {
            int64_t translated_index = (sequence & (capacity_ - 1)) ; 
            return translated_index ;
        }

        bool SetCapacity(size_t capacity) {
            bool is_power2 =  capacity && !( (capacity-1) & capacity ) ; 
            if( is_power2 ==0 ) {
                DEBUG_ELOG("Buffer capacity error: power of 2 required!");
                return false;
            }

            try {
                buffer_.reserve(capacity);
            } catch (const std::length_error& le) {
                DEBUG_ELOG("Length error: " << le.what() );
                return false;
            }
            capacity_ = capacity;
            return true;
        }

    private:
        size_t          capacity_ ;
        std::vector<T>  buffer_;
        RingBuffer(const RingBuffer&);
        void operator=(const RingBuffer&);
        RingBuffer(RingBuffer&&);
        void operator=(const RingBuffer&&);
};

#endif //DISRUPTORCPP_RING_BUFFER_HPP