/** * \file * Functions and types for CRC checks. * * Generated on Sat May 12 09:41:12 2018 * by pycrc v0.9.1, https://pycrc.org * using the configuration: * - Width = 4 * - Poly = 0x3 * - XorIn = 0x0 * - ReflectIn = False * - XorOut = 0x0 * - ReflectOut = False * - Algorithm = table-driven * * This file defines the functions crc4itu_init(), crc4itu_update() and crc_finalize(). * * The crc4itu_init() function returns the initial \c crc value and must be called * before the first call to crc4itu_update(). * Similarly, the crc_finalize() function must be called after the last call * to crc4itu_update(), before the \c crc is being used. * is being used. * * The crc4itu_update() function can be called any number of times (including zero * times) in between the crc4itu_init() and crc_finalize() calls. * * This pseudo-code shows an example usage of the API: * \code{.c} * crc_t crc; * unsigned char data[MAX_DATA_LEN]; * size_t data_len; * * crc = crc4itu_init(); * while ((data_len = read_data(data, MAX_DATA_LEN)) > 0) { * crc = crc4itu_update(crc, data, data_len); * } * crc = crc_finalize(crc); * \endcode */ #ifndef CRC4ITU_H #define CRC4ITU_H #include #include #ifdef __cplusplus extern "C" { #endif /** * The definition of the used algorithm. * * This is not used anywhere in the generated code, but it may be used by the * application code to call algorithm-specific code, if desired. */ #define CRC_ALGO_TABLE_DRIVEN 1 /** * The type of the CRC values. * * This type must be big enough to contain at least 4 bits. */ typedef uint_fast8_t crc_t; /** * Calculate the initial crc value. * * \return The initial crc value. */ static inline crc_t crc4itu_init(void) { return 0x0; } /** * Update the crc value with new data. * * \param[in] crc The current crc value. * \param[in] data Pointer to a buffer of \a data_len bytes. * \param[in] data_len Number of bytes in the \a data buffer. * \return The updated crc value. */ crc_t crc4itu_update(crc_t crc, const void *data, size_t data_len); /** * Calculate the final crc value. * * \param[in] crc The current crc value. * \return The final crc value. */ static inline crc_t crc_finalize(crc_t crc) { return crc; } #ifdef __cplusplus } /* closing brace for extern "C" */ #endif #endif /* CRC4ITU_H */