storj/pkg/eestream/rs.go

50 lines
1.1 KiB
Go

// Copyright (C) 2018 Storj Labs, Inc.
// See LICENSE for copying information.
package eestream
import (
"github.com/vivint/infectious"
)
type rsScheme struct {
fc *infectious.FEC
erasureShareSize int
}
// NewRSScheme returns a Reed-Solomon-based ErasureScheme.
func NewRSScheme(fc *infectious.FEC, erasureShareSize int) ErasureScheme {
return &rsScheme{fc: fc, erasureShareSize: erasureShareSize}
}
func (s *rsScheme) Encode(input []byte, output func(num int, data []byte)) (
err error) {
return s.fc.Encode(input, func(s infectious.Share) {
output(s.Number, s.Data)
})
}
func (s *rsScheme) Decode(out []byte, in map[int][]byte) ([]byte, error) {
shares := make([]infectious.Share, 0, len(in))
for num, data := range in {
shares = append(shares, infectious.Share{Number: num, Data: data})
}
return s.fc.Decode(out, shares)
}
func (s *rsScheme) ErasureShareSize() int {
return s.erasureShareSize
}
func (s *rsScheme) StripeSize() int {
return s.erasureShareSize * s.fc.Required()
}
func (s *rsScheme) TotalCount() int {
return s.fc.Total()
}
func (s *rsScheme) RequiredCount() int {
return s.fc.Required()
}