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}

		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)}