crc

Documentation

Overview

Package crc provides CRC calculation functions which leverage IAA hardware.

Index

• Constants
• func Ready() bool
• func YieldProcessor(c *CRC32C)
• type CRC32C
  • func NewCRC32C(opts ...CRC32COption) (*CRC32C, error)
  • func (c *CRC32C) BlockSize() int
  • func (c *CRC32C) Reset()
  • func (c *CRC32C) Size() int
  • func (c *CRC32C) Sum(b []byte) []byte
  • func (c *CRC32C) Sum32() uint32
  • func (c *CRC32C) Write(data []byte) (n int, err error)
• type CRC32COption
• type Calculator
  • func NewCalculator() (*Calculator, error)
  • func (calc *Calculator) CheckSum16(data []byte, poly uint16) (uint16, error)
  • func (calc *Calculator) CheckSum32(data []byte, poly uint32) (uint32, error)
  • func (calc *Calculator) CheckSum64(data []byte, poly uint64) (uint64, error)

Constants

const (
	// ISO polynomial value
	ISO uint64 = 0xD800000000000000
	// ECMA polynomial value
	ECMA uint64 = 0xC96C5795D7870F42
)

const (
	// IEEE polynomial value
	IEEE uint32 = 0xedb88320
	// Castagnoli polynomial value
	Castagnoli uint32 = 0x82f63b78
	// Koopman polynomial value
	Koopman uint32 = 0xeb31d82e
)

const (
	// CCITT polynomial value
	CCITT uint16 = 0x8408
	// T10DIF polynomial value
	T10DIF uint16 = 0x8BB7
)

Functions

func Ready

func Ready() bool

Ready returns true if the device is ready for use.

func YieldProcessor

func YieldProcessor(c *CRC32C)

YieldProcessor yields the processor while submitting the CRC job to hardware, instead of busy polling the result.

Types

type CRC32C

type CRC32C struct {
	// contains filtered or unexported fields
}

CRC32C represents a CRC32C calculator. This calculator uses Castagnoli's polynomial, which is widely used in iSCSI. The calculator is compliant with the hash.Hash32 interface.

func NewCRC32C

func NewCRC32C(opts ...CRC32COption) (*CRC32C, error)

NewCRC32C function initializes a new CRC32C hasher. This hasher is compliant with the hash.Hash32 interface. Returns an error if no hardware device is detected (Intel® DSA).

func (*CRC32C) BlockSize

func (c *CRC32C) BlockSize() int

BlockSize returns the hash's underlying block size. The Write method must be able to accept any amount of data, but it may operate more efficiently if all writes are a multiple of the block size.

func (*CRC32C) Reset

func (c *CRC32C) Reset()

Reset resets the Hash to its initial state.

func (*CRC32C) Size

func (c *CRC32C) Size() int

Size returns the number of bytes Sum will return.

func (*CRC32C) Sum

func (c *CRC32C) Sum(b []byte) []byte

Sum appends the current hash to b and returns the resulting slice. It does not change the underlying hash state.

func (*CRC32C) Sum32

func (c *CRC32C) Sum32() uint32

func (*CRC32C) Write

func (c *CRC32C) Write(data []byte) (n int, err error)

type CRC32COption

type CRC32COption func(c *CRC32C)

type Calculator

type Calculator struct {
	// contains filtered or unexported fields
}

Calculator is used for CRC64 calculation Notice: the data size should be less than your device's max_transfer_size.

func NewCalculator

func NewCalculator() (*Calculator, error)

NewCalculator creates a new Calculator to be used for CRC64 calculation

func (*Calculator) CheckSum16

func (calc *Calculator) CheckSum16(data []byte, poly uint16) (uint16, error)

CheckSum16 calculates the CRC16 checksum for the given data and polynomial value

func (*Calculator) CheckSum32

func (calc *Calculator) CheckSum32(data []byte, poly uint32) (uint32, error)

CheckSum32 calculates the CRC32 checksum for the given data and polynomial value

func (*Calculator) CheckSum64

func (calc *Calculator) CheckSum64(data []byte, poly uint64) (uint64, error)

CheckSum64 calculates the CRC64 checksum for the given data and polynomial value