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@ -1,8 +1,40 @@ |
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package erasure_coding |
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package erasure_coding |
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import ( |
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"io" |
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"os" |
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"github.com/klauspost/reedsolomon" |
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) |
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const ( |
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const ( |
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DataShardsCount = 10 |
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DataShardsCount = 10 |
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ParityShardsCount = 4 |
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ParityShardsCount = 4 |
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ErasureCodingLargeBlockSize = 1024 * 1024 * 1024 // 1GB
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ErasureCodingLargeBlockSize = 1024 * 1024 * 1024 // 1GB
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ErasureCodingSmallBlockSize = 1024 * 1024 // 1MB
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ErasureCodingSmallBlockSize = 1024 * 1024 // 1MB
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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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} |