//
// Keys and values should be UTF-8, but the number of bad writers out there
// forces us to be a more liberal.
// Thus, we only reject all keys with NUL, and only reject NULs in values
// for the PAX version of the USTAR string fields.
// The key must not contain an '=' character.
func validPAXRecord(k, v string) bool {
	if k == "" || strings.Contains(k, "=") {
		return false
	}
	switch k {

			Uid:      010000000,
			ModTime:  time.Unix(0, 0),
			Typeflag: '0',
		}},
	}, {
		// USTAR archive with a regular entry with non-zero device numbers.
		file: "testdata/ustar-file-devs.tar",
		headers: []*Header{{
			Name:     "file",
			Mode:     0644,
			Typeflag: '0',
			ModTime:  time.Unix(0, 0),
			Devmajor: 1,
			Devminor: 1,

		}
	}
}

func Benchmark(b *testing.B) {
	type file struct {
		hdr  *Header
		body []byte
	}

	vectors := []struct {
		label string
		files []file
	}{{
		"USTAR",
		[]file{{
			&Header{Name: "bar", Mode: 0640, Size: int64(3)},
			[]byte("foo"),
		}, {
			&Header{Name: "world", Mode: 0640, Size: int64(5)},
			[]byte("hello"),
		}},
	}, {
		"GNU",