77 lines
1.6 KiB
77 lines
1.6 KiB
package erasure_coding
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import (
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"io"
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"os"
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"testing"
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"github.com/klauspost/reedsolomon"
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)
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func TestEncodingDecoding(t *testing.T) {
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largeBlockSize := int64(10000)
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smallBlockSize := int64(100)
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bufferSize := 50
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file, err := os.OpenFile("1.dat", os.O_RDONLY, 0)
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if err != nil {
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t.Logf("failed to open dat file: %v", err)
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}
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fi, err := file.Stat()
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if err != nil {
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t.Logf("failed to stat dat file: %v", err)
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}
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remainingSize := fi.Size()
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var processedSize int64
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enc, err := reedsolomon.New(DataShardsCount, ParityShardsCount)
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if err != nil {
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t.Logf("failed to create encoder: %v", err)
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}
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buffers := make([][]byte, DataShardsCount+ParityShardsCount)
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for i, _ := range buffers {
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buffers[i] = make([]byte, bufferSize)
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}
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for remainingSize > largeBlockSize*DataShardsCount {
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encodeData(file, enc, processedSize, largeBlockSize, buffers)
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remainingSize -= largeBlockSize * DataShardsCount
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processedSize += largeBlockSize * DataShardsCount
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}
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for remainingSize > 0 {
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encodeData(file, enc, processedSize, smallBlockSize, buffers)
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remainingSize -= smallBlockSize * DataShardsCount
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processedSize += smallBlockSize * DataShardsCount
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}
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}
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func encodeData(file *os.File, enc reedsolomon.Encoder, startOffset, blockSize int64, buffers [][]byte) error {
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// read data into buffers
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for i := 0; i < DataShardsCount; i++ {
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n, err := file.ReadAt(buffers[i], startOffset+blockSize*int64(i))
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if err != nil {
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if err != io.EOF {
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return err
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}
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}
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if n < len(buffers[i]) {
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for t := len(buffers[i]) - 1; t >= n; t-- {
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buffers[i][t] = 0
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}
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}
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}
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err := enc.Encode(buffers)
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if err != nil {
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return err
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}
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return nil
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}
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