62 lines
1.5 KiB
Go
62 lines
1.5 KiB
Go
// Copyright (C) 2019 Storj Labs, Inc.
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// See LICENSE for copying information.
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package eestream
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import (
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"github.com/vivint/infectious"
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)
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type unsafeRSScheme struct {
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fc *infectious.FEC
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erasureShareSize int
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}
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// NewUnsafeRSScheme returns a Reed-Solomon-based ErasureScheme without error correction.
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func NewUnsafeRSScheme(fc *infectious.FEC, erasureShareSize int) ErasureScheme {
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return &unsafeRSScheme{fc: fc, erasureShareSize: erasureShareSize}
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}
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func (s *unsafeRSScheme) EncodeSingle(input, output []byte, num int) (err error) {
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return s.fc.EncodeSingle(input, output, num)
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}
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func (s *unsafeRSScheme) Encode(input []byte, output func(num int, data []byte)) (
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err error) {
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return s.fc.Encode(input, func(s infectious.Share) {
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output(s.Number, s.Data)
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})
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}
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func (s *unsafeRSScheme) Decode(out []byte, in map[int][]byte) ([]byte, error) {
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shares := make([]infectious.Share, 0, len(in))
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for num, data := range in {
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shares = append(shares, infectious.Share{Number: num, Data: data})
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}
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stripe := make([]byte, s.RequiredCount()*s.ErasureShareSize())
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err := s.fc.Rebuild(shares, func(share infectious.Share) {
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copy(stripe[share.Number*s.ErasureShareSize():], share.Data)
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})
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if err != nil {
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return nil, err
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}
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return stripe, nil
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}
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func (s *unsafeRSScheme) ErasureShareSize() int {
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return s.erasureShareSize
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}
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func (s *unsafeRSScheme) StripeSize() int {
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return s.erasureShareSize * s.fc.Required()
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}
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func (s *unsafeRSScheme) TotalCount() int {
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return s.fc.Total()
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}
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func (s *unsafeRSScheme) RequiredCount() int {
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return s.fc.Required()
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}
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