var tarinsecurepath = godebug.New("tarinsecurepath")

var (
	ErrHeader          = errors.New("archive/tar: invalid tar header")
	ErrWriteTooLong    = errors.New("archive/tar: write too long")
	ErrFieldTooLong    = errors.New("archive/tar: header field too long")
	ErrWriteAfterClose = errors.New("archive/tar: write after close")
	ErrInsecurePath    = errors.New("archive/tar: insecure file path")

		name    string
		extra   []byte
		wanterr error
	}{
		{
			name:    strings.Repeat("x", 1<<16),
			extra:   []byte{},
			wanterr: errLongName,
		},
		{
			name:    "long_extra",
			extra:   bytes.Repeat([]byte{0xff}, 1<<16),
			wanterr: errLongExtra,
		},
	}

	// write a zip file
	buf := new(bytes.Buffer)
	w := NewWriter(buf)

	for _, test := range headerTests {

		}
		c0 := sep[0]
		c1 := sep[1]
		i := 0
		t := len(s) - n + 1
		fails := 0
		for i < t {
			if s[i] != c0 {
				// IndexByte is faster than bytealg.Index, so use it as long as
				// we're not getting lots of false positives.
				o := IndexByte(s[i+1:t], c0)
				if o < 0 {
					return -1
				}
				i += o + 1
			}
			if s[i+1] == c1 && Equal(s[i:i+n], sep) {

<p>
Function literals are <i>closures</i>: they may refer to variables
defined in a surrounding function. Those variables are then shared between
the surrounding function and the function literal, and they survive as long
as they are accessible.
</p>


<h3 id="Primary_expressions">Primary expressions</h3>

<p>
Primary expressions are the operands for unary and binary expressions.
</p>

		// It was verified to work with GNU tar 1.27.1 and BSD tar 3.1.2.
		//  dd if=/dev/zero bs=1G count=16 >> writer-big-long.tar
		//  gnutar -xvf writer-big-long.tar
		//  bsdtar -xvf writer-big-long.tar
		//
		// This file is in PAX format.
		file: "testdata/writer-big-long.tar",
		tests: []testFnc{
			testHeader{Header{
				Typeflag: TypeReg,
				Name:     strings.Repeat("longname/", 15) + "16gig.txt",

	"bufio"
	"encoding/binary"
	"errors"
	"hash"
	"hash/crc32"
	"io"
	"io/fs"
	"strings"
	"unicode/utf8"
)

var (
	errLongName  = errors.New("zip: FileHeader.Name too long")
	errLongExtra = errors.New("zip: FileHeader.Extra too long")
)

// Writer implements a zip file writer.
type Writer struct {
	cw          *countWriter
	dir         []*header
	last        *fileWriter
	closed      bool