}

func newBitrotWriter(disk StorageAPI, origvolume, volume, filePath string, length int64, algo BitrotAlgorithm, shardSize int64) io.Writer {
	if algo == HighwayHash256S {
		return newStreamingBitrotWriter(disk, origvolume, volume, filePath, length, algo, shardSize)
	}
	return newWholeBitrotWriter(disk, volume, filePath, algo, shardSize)
}

	h := algo.New()
	return &streamingBitrotReader{
		disk:       disk,
		data:       data,
		volume:     volume,
		filePath:   filePath,
		tillOffset: ceilFrac(tillOffset, shardSize)*int64(h.Size()) + tillOffset,
		h:          h,
		shardSize:  shardSize,
		hashBytes:  make([]byte, h.Size()),
	}

	// Fill buffers
	b := globalBytePoolCap.Load().Get()
	shardSize := int(e.ShardSize())
	if cap(b) < len(readers)*shardSize {
		// We should always have enough capacity, but older objects may be bigger.
		globalBytePoolCap.Load().Put(b)
		b = nil
	} else {
		// Seed the buffers.
		for i := range bufs {
			bufs[i] = b[i*shardSize : (i+1)*shardSize]
		}
	}

	return &parallelReader{
		readers:       readers,

	return nil
}

// Returns whole-file bitrot writer.
func newWholeBitrotWriter(disk StorageAPI, volume, filePath string, algo BitrotAlgorithm, shardSize int64) io.WriteCloser {
	return &wholeBitrotWriter{disk, volume, filePath, shardSize, algo.New()}
}

// Implementation to verify bitrot for the whole file.
type wholeBitrotReader struct {
	disk       StorageAPI
	volume     string
	filePath   string

		writers := make([]io.Writer, len(disks))
		for i, disk := range disks {
			writers[i] = newBitrotWriter(disk, "", "testbucket", "object", erasure.ShardFileSize(test.data), writeAlgorithm, erasure.ShardSize())
		}
		n, err := erasure.Encode(context.Background(), bytes.NewReader(data), writers, buffer, erasure.dataBlocks+1)
		closeBitrotWriters(writers)
		if err != nil {

	return numShards*e.ShardSize() + lastShardSize
}

// ShardFileOffset - returns the effective offset where erasure reading begins.
func (e *Erasure) ShardFileOffset(startOffset, length, totalLength int64) int64 {
	shardSize := e.ShardSize()
	shardFileSize := e.ShardFileSize(totalLength)
	endShard := (startOffset + length) / e.blockSize
	tillOffset := endShard*shardSize + shardSize
	if tillOffset > shardFileSize {

                    op.size(pager.getPageSize());
                    if (fessConfig.getSearchlogAggShardSizeAsInteger() >= 0) {
                        op.shardSize(fessConfig.getSearchlogAggShardSizeAsInteger());
                    }
                }, null);
            });
            final Terms agg = list.getAggregations().get(SearchLogPager.LOG_TYPE_CLICK_COUNT);

		writers := make([]io.Writer, len(disks))
		for i, disk := range disks {
			writers[i] = newBitrotWriter(disk, "", "testbucket", "testobject", erasure.ShardFileSize(test.size), test.algorithm, erasure.ShardSize())
		}
		_, err = erasure.Encode(context.Background(), bytes.NewReader(data), writers, buffer, erasure.dataBlocks+1)
		closeBitrotWriters(writers)
		if err != nil {

	lastBlockSize := totalLength % e.BlockSize
	lastShardSize := ceilFrac(lastBlockSize, int64(e.DataBlocks))
	return numShards*e.ShardSize() + lastShardSize
}

// ShardSize - returns actual shared size from erasure blockSize.
func (e ErasureInfo) ShardSize() int64 {
	return ceilFrac(e.BlockSize, int64(e.DataBlocks))
}

// IsValid - tells if erasure info fields are valid.
func (fi FileInfo) IsValid() bool {

	algo = HighwayHash256S
	shardSize := int64(1024 * 1024)
	shard := make([]byte, shardSize)
	w := newStreamingBitrotWriter(storage, "", volName, fileName, size, algo, shardSize)
	reader := bytes.NewReader(data)
	for {
		// Using io.Copy instead of this loop will not work for us as io.Copy
		// will use bytes.Reader.WriteTo() which will not do shardSize'ed writes
		// causing error.