Crate ps_ecc 

Reed-Solomon error-correcting codes over GF(256).

The crate offers three layers of API:

• The free functions encode, decode, and validate pick the appropriate format automatically: messages that fit a single Reed-Solomon codeword (at most 255 - 2 * parity bytes) are encoded directly, and longer messages use the long ECC format, which splits the message into segments of at most 255 bytes behind a checksummed header.
• ReedSolomon encodes, validates, and corrects single codewords, either attached (parity || data in one slice) or detached (parity and data as separate slices).
• Polynomial and euclidean expose the underlying GF(256) polynomial arithmetic.

The parity count parameter is the error-correction capability: the number of byte errors a codeword can recover from, each costing two parity bytes. It is capped at MAX_PARITY (63). The detached APIs instead take the generated parity bytes themselves, capped at MAX_PARITY_BYTES (126).

Structs

Codeword

A decoded codeword exposing the message bytes.

LongEccHeader

The 32-byte header of a long ECC codeword.

ParityBytes

Stack-allocated parity bytes returned by crate::ReedSolomon::generate_parity.

Polynomial

A polynomial over GF(256) with at most 255 coefficients.

ReedSolomon

A Reed-Solomon codec over GF(256) for codewords of at most 255 bytes.

Enums

Cow

A borrowed-or-owned byte buffer.

DecodeError

Errors returned by the free decode function.

EccError

Umbrella error over encoding and decoding.

EncodeError

Errors returned by the free encode function.

EuclideanError

Errors returned by euclidean.

GFError

Errors of GF(256) field arithmetic.

LongEccDecodeError

Errors of long ECC decoding.

LongEccEncodeError

Errors of long ECC encoding.

LongEccFastValidateError

LongEccHeaderConstructorError

Errors returned by LongEccHeader::new.

LongEccHeaderFromByteSliceError

Errors returned by LongEccHeader::from_byte_slice.

LongEccHeaderFromBytesError

Errors returned by LongEccHeader::from_bytes.

OverlapFactor

Approximate number of distinct codewords covering each byte.

PolynomialDivError

Errors of polynomial division and remainder.

PolynomialFromSliceError

Errors returned when constructing a Polynomial from a slice.

PolynomialMulError

Errors of polynomial multiplication.

PolynomialSetCoefficientsError

Errors returned by Polynomial::set_coefficients.

PolynomialXorError

Errors of polynomial XOR with a coefficient iterator.

RSComputeErrorsError

Errors returned by ReedSolomon::compute_errors.

RSConstructorError

Errors returned by ReedSolomon::new and by the detached-parity methods when the parity slice itself is invalid.

RSDecodeError

Errors returned by the decoding and correction methods of ReedSolomon.

RSEncodeError

Errors returned by ReedSolomon::encode.

RSGenerateParityError

Errors returned by ReedSolomon::generate_parity.

Constants

MAX_PARITY

Maximum error-correction capability of a Reed-Solomon codec.

MAX_PARITY_BYTES

Maximum parity byte count, equal to MAX_PARITY * 2.

Functions

decode

Verifies the error-correcting code and returns the message.

encode

Encodes a message by adding an error-correcting code.

euclidean

Extended Euclidean algorithm for Reed-Solomon decoding.

validate

Validates that a received codeword is pristine.