}

	if size >= 0 {
		r := ioutil.HardLimitReader(src, size)
		if !disableMD5 {
			if _, ok := src.(etag.Tagger); !ok {
				src = etag.NewReader(ctx, r, MD5, forceMD5)
			} else {
				src = etag.Wrap(r, src)
			}
		} else {
			src = r
		}
	} else if _, ok := src.(etag.Tagger); !ok {
		if !disableMD5 {
			src = etag.NewReader(ctx, src, MD5, forceMD5)
		}
	}
	var h hash.Hash

			isDir := len(file.Name) > 0 && file.Name[len(file.Name)-1] == '/'
			name := toValidName(file.Name)
			if name == "" {
				continue
			}

			if idx, ok := files[name]; ok {
				r.fileList[idx].isDup = true
				continue
			}
			if idx, ok := knownDirs[name]; ok {
				r.fileList[idx].isDup = true
				continue
			}

			for dir := path.Dir(name); dir != "."; dir = path.Dir(dir) {
				dirs[dir] = true
			}

	default:
		return n, nil
	}
}

func (sr *sparseFileReader) WriteTo(w io.Writer) (n int64, err error) {
	ws, ok := w.(io.WriteSeeker)
	if ok {
		if _, err := ws.Seek(0, io.SeekCurrent); err != nil {
			ok = false // Not all io.Seeker can really seek
		}
	}
	if !ok {
		return io.Copy(w, struct{ io.Reader }{sr})
	}

	var writeLastByte bool
	pos0 := sr.pos