56 lines
917 B
Go
56 lines
917 B
Go
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package rlepluslazy
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import (
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"encoding/binary"
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bitvector "github.com/filecoin-project/go-lotus/lib/rlepluslazy/internal"
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)
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func EncodeRuns(rit RunIterator, buf []byte) ([]byte, error) {
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v := bitvector.NewBitVector(buf[:0], bitvector.LSB0)
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v.Extend(0, 2, bitvector.LSB0) // Version
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first := true
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varBuf := make([]byte, binary.MaxVarintLen64)
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for rit.HasNext() {
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run, err := rit.NextRun()
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if err != nil {
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return nil, err
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}
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if first {
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if run.Val {
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v.Push(1)
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} else {
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v.Push(0)
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}
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first = false
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}
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switch {
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case run.Len == 1:
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v.Push(1)
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case run.Len < 16:
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v.Push(0)
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v.Push(1)
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v.Extend(byte(run.Len), 4, bitvector.LSB0)
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case run.Len >= 16:
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v.Push(0)
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v.Push(0)
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numBytes := binary.PutUvarint(varBuf, run.Len)
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for i := 0; i < numBytes; i++ {
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v.Extend(varBuf[i], 8, bitvector.LSB0)
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}
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}
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}
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if first {
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v.Push(0)
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}
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return v.Buf, nil
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}
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