aaru-dps/Aaru.Checksums.Native
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Add documentation.

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This commit is contained in:
Natalia Portillo
2023-09-23 18:10:44 +01:00
parent 3358d66f0a
commit 33f021fd54
22 changed files with 658 additions and 48 deletions
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42
crc16_ccitt.c
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@@ -22,6 +22,15 @@
#include "library.h"
#include "crc16_ccitt.h"
/**
* @brief Initializes the CRC-16 checksum algorithm with the CCITT polynomial.
*
* This function initializes the state variables required for the CRC-16
* checksum algorithm using the CCITT polynomial. It prepares the algorithm
* to calculate the checksum for a new data set.
*
* @return Pointer to a structure containing the checksum state.
*/
AARU_EXPORT crc16_ccitt_ctx* AARU_CALL crc16_ccitt_init(void)
{
crc16_ccitt_ctx* ctx = (crc16_ccitt_ctx*)malloc(sizeof(crc16_ccitt_ctx));
@@ -33,6 +42,20 @@ AARU_EXPORT crc16_ccitt_ctx* AARU_CALL crc16_ccitt_init(void)
return ctx;
}
/**
* @brief Updates the CRC-16 checksum with new data.
*
* This function updates the CRC-16 checksum.
* The checksum is updated for the given data by using the CCITT polynomial.
* The algorithm continues the checksum calculation from the previous state,
* so it can be used to update the checksum with new data as it is read.
*
* @param ctx Pointer to the CRC-16 context structure.
* @param data Pointer to the input data buffer.
* @param len The length of the input data buffer.
*
* @returns 0 on success, -1 on error.
*/
AARU_EXPORT int AARU_CALL crc16_ccitt_update(crc16_ccitt_ctx* ctx, const uint8_t* data, uint32_t len)
{
// Unroll according to Intel slicing by uint8_t
@@ -79,6 +102,17 @@ AARU_EXPORT int AARU_CALL crc16_ccitt_update(crc16_ccitt_ctx* ctx, const uint8_t
return 0;
}
/**
* @brief Finalizes the calculation of the CRC-16 checksum.
*
* This function finalizes the calculation of the CRC-16 checksum and returns
* its value.
*
* @param[in] ctx Pointer to the CRC-16 context structure.
* @param[out] checksum Pointer to a 16-bit unsigned integer to store the checksum value.
*
* @returns 0 on success, -1 on error.
*/
AARU_EXPORT int AARU_CALL crc16_ccitt_final(crc16_ccitt_ctx* ctx, uint16_t* crc)
{
if(!ctx) return -1;
@@ -88,6 +122,14 @@ AARU_EXPORT int AARU_CALL crc16_ccitt_final(crc16_ccitt_ctx* ctx, uint16_t* crc)
return 0;
}
/**
* @brief Frees the resources allocated for the CRC-16 checksum context.
*
* This function should be called to release the memory used by the CRC-16 checksum
* context structure after it is no longer needed.
*
* @param ctx The CRC-16 checksum context structure, to be freed.
*/
AARU_EXPORT void AARU_CALL crc16_ccitt_free(crc16_ccitt_ctx* ctx)
{
if(ctx) free(ctx);