fifo.h

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/** @file fifo.h
	@brief Generic bit FIFO functions. */

#ifndef FIFO_H
#define FIFO_H
#include <cstdint>
#include <vector>

/** FIFO object */
class Fifo
{
public:
	Fifo(int size); ///< Initialize FIFO using the specified size (in bytes)
	Fifo(const Fifo &f);  ///< Copy constructor
	uint32_t GetBitsUi(int nbits);   ///< Get an unsigned integer of the specified number of bits (from MSb to LSb)
	int32_t GetBitsI(int nbits);   ///< Get a signed integer of the specified number of bits (from MSb to LSb)
	void PutBits(uint32_t d, int nbits);   ///< Put an unsigned integer of the specified number of bits into the FIFO (from MSb to LSb)
	void PutBits(int32_t d, int nbits);   ///< Put a signed integer of the specified number of bits into the FIFO (from MSb to LSb)
	uint32_t FlipGetBitsUi(int nbits);   ///< Get an unsigned integer of the specified number of bits (from LSb to MSb)
	int32_t FlipGetBitsI(int nbits);   ///< Get an integer number of the specified number of bits (from LSb to MSb)
	/** Get a datum value from the FIFO
		@param nbits				number of bits in datum
		@param is_signed			flag indicating if data value is signed
		@param direction_r2l		true => right-to-left order, false => left-to-right order
		@return						datum value */
	int32_t GetDatum(int nbits, bool is_signed, bool direction_r2l); 
	void FlipPutBits(uint32_t d, int nbits);  ///< Put an unsigned integer of the specified number of bits into the FIFO (from LSb to MSb)
	void FlipPutBits(int32_t d, int nbits);  ///< Put a signed integer of the specified number of bits into the FIFO (from LSb to MSb)
	/** Put a datum value into the FIFO
		@param datum				value to add
		@param nbits				number of bits in datum
		@param direction_r2l		true => right-to-left order, false => left-to-right order */
	void PutDatum(int32_t datum, int nbits, bool direction_r2l);
	void Clear();  ///< Clear the FIFO
	int m_fullness;   ///< FIFO fullness (in bits)
private:
	std::vector<uint8_t> m_data;  ///< data storage
	int m_size;    ///< Size of FIFO
	int m_read_ptr;   ///< FIFO read pointer
	int m_write_ptr;   ///< FIFO write pointer
	int m_max_fullness;   ///< FIFO maximum fullnesss
	int m_byte_ctr;   ///< FIFO byte counter
};

#endif