return nil, nil, err // EOF is okay here; exactly 0 bytes read
	}
	if bytes.Equal(tr.blk[:], zeroBlock[:]) {
		if _, err := io.ReadFull(tr.r, tr.blk[:]); err != nil {
			return nil, nil, err // EOF is okay here; exactly 1 block of zeros read
		}
		if bytes.Equal(tr.blk[:], zeroBlock[:]) {
			return nil, nil, io.EOF // normal EOF; exactly 2 block of zeros read
		}

			t.Errorf("test %d, Header.Size = %d, want %d", i, hdr.Size, v.wantSize)
		}
	}
}

func TestReadGNUSparsePAXHeaders(t *testing.T) {
	padInput := func(s string) string {
		return s + string(zeroBlock[:blockPadding(int64(len(s)))])
	}

	vectors := []struct {
		inputData string
		inputHdrs map[string]string
		wantMap   sparseDatas
		wantSize  int64
		wantName  string
		wantErr   error