return nil, ErrHeader
	}

	// There should be two numbers in sparseMap for each entry.
	sparseMap := strings.Split(paxHdrs[paxGNUSparseMap], ",")
	if len(sparseMap) == 1 && sparseMap[0] == "" {
		sparseMap = sparseMap[:0]
	}
	if int64(len(sparseMap)) != 2*numEntries {
		return nil, ErrHeader
	}

	// Loop through the entries in the sparse map.