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/**
* \file
* Functions and types for CRC checks.
*
* Generated on Wed Mar 18 12:41:20 2020
* by pycrc v0.9.2, https://pycrc.org
* using the configuration:
* - Width = 32
* - Poly = 0x04c11db7
* - XorIn = 0xffffffff
* - ReflectIn = True
* - XorOut = 0xffffffff
* - ReflectOut = True
* - Algorithm = table-driven
* - SliceBy = 8
*
* This file defines the functions crc_init(), crc_update() and crc_finalize().
*
* The crc_init() function returns the inital \c crc value and must be called
* before the first call to crc_update().
* Similarly, the crc_finalize() function must be called after the last call
* to crc_update(), before the \c crc is being used.
* is being used.
*
* The crc_update() function can be called any number of times (including zero
* times) in between the crc_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 = crc_init();
* while ((data_len = read_data(data, MAX_DATA_LEN)) > 0) {
* crc = crc_update(crc, data, data_len);
* }
* crc = crc_finalize(crc);
* \endcode
*/
#ifndef CRC32_H
#define CRC32_H
#include <stdlib.h>
#include <stdint.h>
#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 32 bits.
*/
typedef uint_fast32_t crc_t;
/**
* Calculate the initial crc value.
*
* \return The initial crc value.
*/
static inline crc_t crc_init(void)
{
return 0xffffffff;
}
/**
* 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 crc_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 ^ 0xffffffff;
}
#ifdef __cplusplus
} /* closing brace for extern "C" */
#endif
#endif /* CRC32_H */
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