Namespace: go.std.hash.crc32

v1.0

Contents

• Summary
• Index
• Constants
• Variables
• Functions, Macros, and Special Forms
• Types

Summary

Provides a low-level interface to the hash/crc32 package.

Package crc32 implements the 32-bit cyclic redundancy check, or CRC-32,
checksum. See https://en.wikipedia.org/wiki/Cyclic_redundancy_check for
information.

Polynomials are represented in LSB-first form also known as reversed representation.

See https://en.wikipedia.org/wiki/Mathematics_of_cyclic_redundancy_checks#Reversed_representations_and_reciprocal_polynomials
for information.

Index

• *Table
• Castagnoli
• Checksum
• ChecksumIEEE
• IEEE
• IEEETable
• Koopman
• MakeTable
• New
• NewIEEE
• Size
• Table
• Update
• arrayOfTable

Legend

Constant Variable Function Macro Special form Type GoVar Receiver/Method

Constants

Constants are variables with :const true in their metadata. Joker currently does not recognize them as special; as such, it allows redefining them or their values.

• Castagnoli

  Int v1.0

  Castagnoli's polynomial, used in iSCSI.
  Has better error detection characteristics than IEEE.
  https://dx.doi.org/10.1109/26.231911
  

• IEEE

  Int v1.0

  IEEE is by far and away the most common CRC-32 polynomial.
  Used by ethernet (IEEE 802.3), v.42, fddi, gzip, zip, png, ...
  

• Koopman

  Int v1.0

  Koopman's polynomial.
  Also has better error detection characteristics than IEEE.
  https://dx.doi.org/10.1109/DSN.2002.1028931
  

• Size

  Int v1.0

  The size of a CRC-32 checksum in bytes.
  

Variables

• IEEETable

  Var v1.0

  IEEETable is the table for the IEEE polynomial.
  

Functions, Macros, and Special Forms

• Checksum

  Function v1.0

  (Checksum data tab)
  

  Checksum returns the CRC-32 checksum of data
  using the polynomial represented by the Table.
  
  Go input arguments: (data []byte, tab *Table)
  
  Go returns: uint32
  
  Joker input arguments: [^arrayOfByte data, ^*Table tab]
  
  Joker returns: ^Number

• ChecksumIEEE

  Function v1.0

  (ChecksumIEEE data)
  

  ChecksumIEEE returns the CRC-32 checksum of data
  using the IEEE polynomial.
  
  Go input arguments: (data []byte)
  
  Go returns: uint32
  
  Joker input arguments: [^arrayOfByte data]
  
  Joker returns: ^Number

• MakeTable

  Function v1.0

  (MakeTable poly)
  

  MakeTable returns a Table constructed from the specified polynomial.
  The contents of this Table must not be modified.
  
  Go input arguments: (poly uint32)
  
  Go returns: *Table
  
  Joker input arguments: [^Number poly]
  
  Joker returns: ^*Table

• New

  Function v1.0

  (New tab)
  

  New creates a new hash.Hash32 computing the CRC-32 checksum using the
  polynomial represented by the Table. Its Sum method will lay the
  value out in big-endian byte order. The returned Hash32 also
  implements encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to
  marshal and unmarshal the internal state of the hash.
  
  Go input arguments: (tab *Table)
  
  Go returns: hash.Hash32
  
  Joker input arguments: [^*Table tab]
  
  Joker returns: ^go.std.hash/Hash32

• NewIEEE

  Function v1.0

  (NewIEEE)
  

  NewIEEE creates a new hash.Hash32 computing the CRC-32 checksum using
  the IEEE polynomial. Its Sum method will lay the value out in
  big-endian byte order. The returned Hash32 also implements
  encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to marshal
  and unmarshal the internal state of the hash.
  
  Go returns: hash.Hash32
  
  Joker input arguments: []
  
  Joker returns: ^go.std.hash/Hash32

• Update

  Function v1.0

  (Update crc tab p)
  

  Update returns the result of adding the bytes in p to the crc.
  
  Go input arguments: (crc uint32, tab *Table, p []byte)
  
  Go returns: uint32
  
  Joker input arguments: [^Number crc, ^*Table tab, ^arrayOfByte p]
  
  Joker returns: ^Number

Types

• *Table

  Concrete Type v1.0

  Table is a 256-word table representing the polynomial for efficient processing.
  

• Table

  Concrete Type v1.0

  Table is a 256-word table representing the polynomial for efficient processing.
  

• arrayOfTable

  Concrete Type v1.0

  Table is a 256-word table representing the polynomial for efficient processing.