// This matches the limit used by libarchive.
	maxSpecialFileSize = 1 << 20
)

// blockPadding computes the number of bytes needed to pad offset up to the
// nearest block edge where 0 <= n < blockSize.
func blockPadding(offset int64) (n int64) {
	return -offset & (blockSize - 1)
}

var zeroBlock block

type block [blockSize]byte

			for _, s := range spd {
				hdr.Size += s.Length
				spb = append(strconv.AppendInt(spb, s.Offset, 10), '\n')
				spb = append(strconv.AppendInt(spb, s.Length, 10), '\n')
			}
			pad := blockPadding(int64(len(spb)))
			spb = append(spb, zeroBlock[:pad]...)
			hdr.Size += int64(len(spb)) // Accounts for encoded sparse map

			// Add and modify appropriate PAX records.
			dir, file := path.Split(realName)

func alignSparseEntries(src []sparseEntry, size int64) []sparseEntry {
	dst := src[:0]
	for _, s := range src {
		pos, end := s.Offset, s.endOffset()
		pos += blockPadding(+pos) // Round-up to nearest blockSize
		if end != size {
			end -= blockPadding(-end) // Round-down to nearest blockSize
		}
		if pos < end {
			dst = append(dst, sparseEntry{Offset: pos, Length: end - pos})
		}
	}
	return dst
}

func (tr *Reader) handleRegularFile(hdr *Header) error {
	nb := hdr.Size
	if isHeaderOnlyType(hdr.Typeflag) {
		nb = 0
	}
	if nb < 0 {
		return ErrHeader
	}

	tr.pad = blockPadding(nb)
	tr.curr = &regFileReader{r: tr.r, nb: nb}
	return nil
}

// handleSparseFile checks if the current file is a sparse format of any type
// and sets the curr reader appropriately.

			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
	}{{