bitrev.h

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/**
 * \addtogroup lib
 * @{
 *
 * \defgroup bitrev Bit Reversal Library
 *
 * This library provides functions for reversing bits in bytes and byte arrays.
 * It's commonly used by radio drivers for protocol compliance (e.g., 802.15.4g).
 *
 * @{
 */
 
/**
 * \file
 *         Bit reversal library header
 * \author
 *         Joakim Eriksson <joakim.eriksson@ri.se>
 */
 
#ifndef BITREV_H_
#define BITREV_H_
 
#include "contiki.h"
 
/**
 * \brief Reverse the bits in a single byte
 * \param byte The input byte
 * \return The byte with bits reversed
 *
 * Example: bitrev_byte(0xF0) returns 0x0F
 */
uint8_t bitrev_byte(uint8_t byte);
 
/**
 * \brief Reverse bits in all bytes of an array (in-place)
 * \param data Pointer to the data array
 * \param len Length of the array in bytes
 *
 * This function modifies the input array in-place, reversing the bit
 * order within each byte. Commonly used for protocol compliance.
 */
void bitrev_array(uint8_t *data, size_t len);
 
/**
 * \brief Reverse bits in all bytes of an array (copy to output)
 * \param input Pointer to the input data array
 * \param output Pointer to the output data array
 * \param len Length of the arrays in bytes
 *
 * This function copies data from input to output while reversing
 * the bit order within each byte. Input and output arrays must not overlap.
 */
void bitrev_array_copy(const uint8_t *input, uint8_t *output, size_t len);
 
#endif /* BITREV_H_ */
 
/** @} */
/** @} */