CRC-32 calculation service

See Quick Start Guide for CRC-32.

This service enables the user to calculate 32-bit CRC using the polynomial defined in the IEEE 802.3 standard, with support for multiple data blocks of arbitrary sizes, and any alignment in memory.

Modules
	Quick Start Guide(s)
	In this section you can find a list of all Quick Start guides related to the CRC-32 calculation service.

Typedefs
typedef uint32_t	crc32_t
	Type to contain 32-bit CRC. More...

Functions
static enum status_code	crc32_calculate (const void *data, size_t length, crc32_t *crc)
	Calculate 32-bit CRC for initial block. More...
enum status_code	crc32_recalculate (const void *data, size_t length, crc32_t *crc)
	Recalculate 32-bit CRC for another block. More...

typedef uint32_t crc32_t

Type to contain 32-bit CRC.

static enum status_code crc32_calculate ( const void *  data, size_t  length, crc32_t *  crc  )

inlinestatic

Calculate 32-bit CRC for initial block.

This function calculates the CRC for the specified data block, which may be first of an arbitrary number of blocks.

The actual calculation is done in crc32_recalculate(), while this function just sets up the initial CRC value.

Parameters

[in]	data	Address of data.
[in]	length	Length of data.
[out]	crc	Address of variable to store the calculated CRC in.

Returns

Status of calculation.

Return values

STATUS_OK	if calculation succeeded.
<other>	if calculation failed somehow.

Note

To calculate the CRC of multiple blocks, use this function first, then crc32_recalculate() for the following blocks.

References crc32_recalculate().

enum status_code crc32_recalculate	(	const void *	data,
		size_t	length,
		crc32_t *	crc
	)

Recalculate 32-bit CRC for another block.

This function recalculates the CRC according to the polynomial CRC32_POLYNOMIAL for the specified data block and initial CRC value.

To reduce the number of databus accesses and thus speed up the calculation, the algorithm is tuned to work with words as much as possible.

Parameters

[in]	data	Address of data.
[in]	length	Length of data.
[in,out]	crc	Address of variable containing current CRC, and to store recalculated CRC in.

Returns

Status of calculation.

Return values

STATUS_OK	if calculation succeeded.
<other>	if calculation failed or could not be started.

Note

To calculate the CRC of multiple blocks, use crc32_calculate() first, then this function for the following blocks.

Attention

This implementation assumes a little-endian architecture.

References _crc32_recalculate_bytes_helper(), COMPLEMENT_CRC, length, STATUS_OK, WORD_ALIGNMENT_MASK, and WORD_SIZE.

Referenced by crc32_calculate().