func FuzzReader(f *testing.F) {
	testdata, err := os.ReadDir("testdata")
	if err != nil {
		f.Fatalf("failed to read testdata directory: %s", err)
	}
	for _, de := range testdata {
		if de.IsDir() {
			continue
		}
		b, err := os.ReadFile(filepath.Join("testdata", de.Name()))
		if err != nil {
			f.Fatalf("failed to read testdata: %s", err)
		}
		f.Add(b)
	}

	f.Fuzz(func(t *testing.T, b []byte) {

0000120 a7 13 d9 06 de 52 81 97 36 b2 d7 b8 fc 2b 5f 55
0000130 23 1f 32 59 cf 30 27 fb e2 8a b9 de 45 dd 63 9c
0000140 4b b5 8b 96 4c 7a 62 62 cc a1 a7 cf fa f1 fe dd
0000150 54 62 11 bf 36 78 b3 c7 b1 b5 f2 61 4d 4e dd 66
0000160 32 2e e6 70 34 5f f4 c9 e6 6c 43 6f da 6b c6 c3
0000170 09 2c ce 09 57 7f d2 7e b4 23 ba 7c 1b 99 bc 22
0000180 3e f1 de 91 2f e3 9c 1b 82 cc c2 84 39 aa e6 de

	}
	if s, err := buf.Peek(1); string(s) != "d" || err != nil {
		t.Fatalf("want %q got %q, err=%v", "d", string(s), err)
	}
	if s, err := buf.Peek(2); string(s) != "de" || err != nil {
		t.Fatalf("want %q got %q, err=%v", "de", string(s), err)
	}
	if _, err := buf.Read(p[0:3]); string(p[0:3]) != "def" || err != nil {
		t.Fatalf("want %q got %q, err=%v", "def", string(p[0:3]), err)
	}

		},
	}, {
		maker: makeSparse{makeReg{"abcde", 5}, sparseDatas{{1, 3}, {6, 0}, {6, 0}, {6, 2}}, 8},
		tests: []testFnc{
			testRemaining{8, 5},
			testWriteTo{fileOps{int64(1), "abc", int64(2), "de"}, 8, nil},
			testRemaining{0, 0},
		},
	}, {
		maker: makeSparse{makeReg{"abcde", 5}, sparseDatas{{1, 3}, {6, 2}}, 10},
		tests: []testFnc{
			testRead{100, "\x00abc\x00\x00de\x00\x00", io.EOF},
		},

but are otherwise ignored.
</p>

<pre>
struct {
	x, y float64 ""  // an empty tag string is like an absent tag
	name string  "any string is permitted as a tag"
	_    [4]byte "ceci n'est pas un champ de structure"
}

// A struct corresponding to a TimeStamp protocol buffer.
// The tag strings define the protocol buffer field numbers;
// they follow the convention outlined by the reflect package.
struct {

	directoryHeaderSignature = 0x02014b50
	directoryEndSignature    = 0x06054b50
	directory64LocSignature  = 0x07064b50
	directory64EndSignature  = 0x06064b50
	dataDescriptorSignature  = 0x08074b50 // de-facto standard; required by OS X Finder
	fileHeaderLen            = 30         // + filename + extra
	directoryHeaderLen       = 46         // + filename + extra + comment
	directoryEndLen          = 22         // + comment

but are otherwise ignored.
</p>

<pre>
struct {
	x, y float64 ""  // an empty tag string is like an absent tag
	name string  "any string is permitted as a tag"
	_    [4]byte "ceci n'est pas un champ de structure"
}

// A struct corresponding to a TimeStamp protocol buffer.
// The tag strings define the protocol buffer field numbers;
// they follow the convention outlined by the reflect package.
struct {

	dirents, err := os.ReadDir(goroot)
	if err != nil {
		return err
	}
	for _, de := range dirents {
		switch de.Name() {
		case "bin", "pkg":
			// We already created GOROOT/bin and GOROOT/pkg above; skip those.
			continue
		}
		if err := adb("push", filepath.Join(goroot, de.Name()), path.Join(deviceGoroot, de.Name())); err != nil {
			return err
		}
	}

	var buf []byte
	if w.isZip64() {
		buf = make([]byte, dataDescriptor64Len)
	} else {
		buf = make([]byte, dataDescriptorLen)
	}
	b := writeBuf(buf)
	b.uint32(dataDescriptorSignature) // de-facto standard, required by OS X
	b.uint32(w.CRC32)
	if w.isZip64() {
		b.uint64(w.CompressedSize64)
		b.uint64(w.UncompressedSize64)
	} else {
		b.uint32(w.CompressedSize)
		b.uint32(w.UncompressedSize)
	}