type parallelReader struct {
	readers       []io.ReaderAt
	orgReaders    []io.ReaderAt
	dataBlocks    int
	offset        int64
	shardSize     int64
	shardFileSize int64
	buf           [][]byte
	readerToBuf   []int
	stashBuffer   []byte
}

// newParallelReader returns parallelReader.
func newParallelReader(readers []io.ReaderAt, e Erasure, offset, totalLength int64) *parallelReader {

		return f.permissions.CriticalOptions[ldapUserN]
	}
	return f.permissions.CriticalOptions["accessKey"]
}

func (f *sftpDriver) Fileread(r *sftp.Request) (ra io.ReaderAt, err error) {
	stopFn := globalSftpMetrics.log(r, f.AccessKey())
	defer stopFn(err)

	flags := r.Pflags()
	if !flags.Read {
		// sanity check
		return nil, os.ErrInvalid
	}

					return err
				}
				if st, err := f.Stat(); err == nil {
					sz = st.Size()
				}
				defer f.Close()
				r = f
			}
			if strings.HasSuffix(file, ".zip") {
				zr, err := zip.NewReader(r.(io.ReaderAt), sz)
				if err != nil {
					return err
				}
				for _, file := range zr.File {
					if !file.FileInfo().IsDir() && strings.HasSuffix(file.Name, "xl.meta") {
						r, err := file.Open()

			partIdx := latestMeta.Parts[partIndex].Index
			partChecksums := latestMeta.Parts[partIndex].Checksums
			tillOffset := erasure.ShardFileOffset(0, partSize, partSize)
			readers := make([]io.ReaderAt, len(latestDisks))
			prefer := make([]bool, len(latestDisks))
			checksumAlgo := erasureInfo.GetChecksumInfo(partNumber).Algorithm
			for i, disk := range latestDisks {
				if disk == OfflineDisk {
					continue

			partLength = length - totalBytesRead
		}

		tillOffset := erasure.ShardFileOffset(partOffset, partLength, partSize)
		// Get the checksums of the current part.
		readers := make([]io.ReaderAt, len(onlineDisks))
		prefer := make([]bool, len(onlineDisks))
		for index, disk := range onlineDisks {
			if disk == OfflineDisk {
				continue
			}
			if !metaArr[index].IsValid() {
				continue
			}

	}

	// Verify it is a regular file, otherwise subsequent Seek is
	// undefined.
	if !st.Mode().IsRegular() {
		return 0, errIsNotRegular
	}

	if verifier == nil {
		n, err = file.ReadAt(buffer, offset)
		return int64(n), err
	}

	h := verifier.algorithm.New()
	if _, err = io.Copy(h, io.LimitReader(file, offset)); err != nil {
		return 0, err
	}