DiskID string
}

// supported FS for Nlink optimization in readdir.
const (
	xfs  = "XFS"
	ext4 = "EXT4"
)

// WalkDir will traverse a directory and return all entries found.
// On success a sorted meta cache stream will be returned.
// Metadata has data stripped, if any.
func (s *xlStorage) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writer) (err error) {
	legacyFS := !(s.fsType == xfs || s.fsType == ext4)

	s.RLock()

//
// WalkDir does not follow symbolic links.
//
// WalkDir calls fn with paths that use the separator character appropriate
// for the operating system. This is unlike [io/fs.WalkDir], which always
// uses slash separated paths.
func WalkDir(root string, fn fs.WalkDirFunc) error {
	info, err := os.Lstat(root)
	if err != nil {
		err = fn(root, nil, err)
	} else {

		return "<" + err.Error() + ">"
	}
	return gofmtBuf.String()
}

func report(err error) {
	scanner.PrintError(os.Stderr, err)
	exitCode = 2
}

func walkDir(path string) {
	filepath.WalkDir(path, visitFile)
}

func visitFile(path string, f fs.DirEntry, err error) error {
	if err == nil && isGoFile(f) {
		err = processFile(path, false)
	}
	if err != nil {
		report(err)

	StatVol(ctx context.Context, volume string) (vol VolInfo, err error)
	DeleteVol(ctx context.Context, volume string, forceDelete bool) (err error)

	// WalkDir will walk a directory on disk and return a metacache stream on wr.
	WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writer) error

	// Metadata operations

		t.Skip("skipping; no GOROOT available")
	}

	goroot, err := filepath.EvalSymlinks(runtime.GOROOT())
	if err != nil {
		t.Fatal("error evaluating GOROOT: ", err)
	}
	var files []string
	err = filepath.WalkDir(goroot, func(path string, info fs.DirEntry, err error) error {
		if err != nil {
			return err
		}
		if !info.IsDir() && strings.HasSuffix(path, ".gz") {
			files = append(files, path)
		}
		return nil
	})

	if err := d.calcError(); err != nil {
		return err
	}
	return d.disk.DeleteVol(ctx, volume, forceDelete)
}

func (d *naughtyDisk) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writer) error {
	if err := d.calcError(); err != nil {
		return err
	}
	return d.disk.WalkDir(ctx, opts, wr)
}

func (d *naughtyDisk) ListDir(ctx context.Context, origvolume, volume, dirPath string, count int) (entries []string, err error) {

// to ErrInvalid is returned on symlink.
//
// Copying stops at and returns the first error encountered.
func CopyFS(dir string, fsys fs.FS) error {
	return fs.WalkDir(fsys, ".", func(path string, d fs.DirEntry, err error) error {
		if err != nil {
			return err
		}

		fpath, err := filepathlite.Localize(path)
		if err != nil {
			return err
		}

		}
		in = f
		defer func() {
			f.Close()
			<-fdSem
		}()
	}

	// Compute the file's size and read its contents with minimal allocations.
	//
	// If we have the FileInfo from filepath.WalkDir, use it to make
	// a buffer of the right size and avoid ReadAll's reallocations.
	//
	// If the size is unknown (or bogus, or overflows an int), fall back to
	// a size-independent ReadAll.
	size := -1

			base.Fatalf("download %s: %v", gotoolchain, err)
		}
		if info.Mode()&0111 == 0 {
			// allowExec sets the exec permission bits on all files found in dir.
			allowExec := func(dir string) {
				err := filepath.WalkDir(dir, func(path string, d fs.DirEntry, err error) error {
					if err != nil {
						return err
					}
					if !d.IsDir() {
						info, err := os.Stat(path)
						if err != nil {
							return err
						}

		readers[i] = newMetacacheReader(r)
		d := disks[i]

		// Send request to each disk.
		go func() {
			var werr error
			if d == nil {
				werr = errDiskNotFound
			} else {
				werr = d.WalkDir(ctx, WalkDirOptions{
					Limit:          opts.perDiskLimit,
					Bucket:         opts.bucket,
					BaseDir:        opts.path,
					Recursive:      opts.recursive,
					ReportNotFound: opts.reportNotFound,