wantValid: false,
	}, {
		in: []sparseEntry{{1, 3}, {2, 2}}, size: 10,
		wantValid: false,
	}}

	for i, v := range vectors {
		gotValid := validateSparseEntries(v.in, v.size)
		if gotValid != v.wantValid {
			t.Errorf("test %d, validateSparseEntries() = %v, want %v", i, gotValid, v.wantValid)
		}
		if !v.wantValid {
			continue
		}
		gotAligned := alignSparseEntries(append([]sparseEntry{}, v.in...), v.size)

type (
	sparseDatas []sparseEntry
	sparseHoles []sparseEntry
)

// validateSparseEntries reports whether sp is a valid sparse map.
// It does not matter whether sp represents data fragments or hole fragments.
func validateSparseEntries(sp []sparseEntry, size int64) bool {
	// Validate all sparse entries. These are the same checks as performed by
	// the BSD tar utility.

		w := testNonEmptyWriter{bb}
		var fw fileWriter
		switch maker := v.maker.(type) {
		case makeReg:
			fw = &regFileWriter{w, maker.size}
			wantStr = maker.wantStr
		case makeSparse:
			if !validateSparseEntries(maker.sph, maker.size) {
				t.Fatalf("invalid sparse map: %v", maker.sph)
			}
			spd := invertSparseEntries(maker.sph, maker.size)
			fw = &regFileWriter{w, maker.makeReg.size}

	}

	// If sp is non-nil, then this is a sparse file.
	// Note that it is possible for len(sp) == 0.
	if err == nil && spd != nil {
		if isHeaderOnlyType(hdr.Typeflag) || !validateSparseEntries(spd, hdr.Size) {
			return ErrHeader
		}
		sph := invertSparseEntries(spd, hdr.Size)
		tr.curr = &sparseFileReader{tr.curr, sph, 0}
	}
	return err
}

		var fr fileReader
		switch maker := v.maker.(type) {
		case makeReg:
			r := testNonEmptyReader{strings.NewReader(maker.str)}
			fr = &regFileReader{r, maker.size}
		case makeSparse:
			if !validateSparseEntries(maker.spd, maker.size) {
				t.Fatalf("invalid sparse map: %v", maker.spd)
			}
			sph := invertSparseEntries(maker.spd, maker.size)
			r := testNonEmptyReader{strings.NewReader(maker.makeReg.str)}