opReadRune4 readOp = 4  // Read rune of size 4.
)

// ErrTooLarge is passed to panic if memory cannot be allocated to store data in a buffer.
var ErrTooLarge = errors.New("bytes.Buffer: too large")
var errNegativeRead = errors.New("bytes.Buffer: reader returned negative count from Read")

const maxInt = int(^uint(0) >> 1)

// Bytes returns a slice of length b.Len() holding the unread portion of the buffer.

				t.Errorf("bad written data at %d %d", startLen, growLen)
			}
		}
	}
}

func TestGrowOverflow(t *testing.T) {
	defer func() {
		if err := recover(); err != ErrTooLarge {
			t.Errorf("after too-large Grow, recover() = %v; want %v", err, ErrTooLarge)
		}
	}()

	buf := NewBuffer(make([]byte, 1))
	const maxInt = int(^uint(0) >> 1)
	buf.Grow(maxInt)
}

// client may instead provide a custom split function.
//
// Scanning stops unrecoverably at EOF, the first I/O error, or a token too
// large to fit in the [Scanner.Buffer]. When a scan stops, the reader may have
// advanced arbitrarily far past the last token. Programs that need more
// control over error handling or large tokens, or must run sequential scans
// on a reader, should use [bufio.Reader] instead.
type Scanner struct {

var writeTests = []WriteTest{
	{
		Name:   "foo",
		Data:   []byte("Rabbits, guinea pigs, gophers, marsupial rats, and quolls."),
		Method: Store,
		Mode:   0666,
	},
	{
		Name:   "bar",
		Data:   nil, // large data set in the test
		Method: Deflate,
		Mode:   0644,
	},
	{
		Name:   "setuid",
		Data:   []byte("setuid file"),
		Method: Deflate,
		Mode:   0755 | fs.ModeSetuid,
	},
	{
		Name:   "setgid",

	n := len(b) * count

	if len(b) == 0 {
		return []byte{}
	}

	// Past a certain chunk size it is counterproductive to use
	// larger chunks as the source of the write, as when the source
	// is too large we are basically just thrashing the CPU D-cache.
	// So if the result length is larger than an empirically-found
	// limit (8KB), we stop growing the source string once the limit

}

const minReadBufferSize = 16
const maxConsecutiveEmptyReads = 100

// NewReaderSize returns a new [Reader] whose buffer has at least the specified
// size. If the argument io.Reader is already a [Reader] with large enough
// size, it returns the underlying [Reader].
func NewReaderSize(rd io.Reader, size int) *Reader {
	// Is it already a Reader?
	b, ok := rd.(*Reader)
	if ok && len(b.buf) >= size {
		return b
	}

	"fmt"
	"internal/godebug"
	"io/fs"
	"math"
	"path"
	"reflect"
	"strconv"
	"strings"
	"time"
)

// BUG: Use of the Uid and Gid fields in Header could overflow on 32-bit
// architectures. If a large value is encountered when decoding, the result
// stored in Header will be the truncated version.

var tarinsecurepath = godebug.New("tarinsecurepath")

var (

type int int

// uint is an unsigned integer type that is at least 32 bits in size. It is a
// distinct type, however, and not an alias for, say, uint32.
type uint uint

// uintptr is an integer type that is large enough to hold the bit pattern of
// any pointer.
type uintptr uintptr

// byte is an alias for uint8 and is equivalent to uint8 in all ways. It is
// used, by convention, to distinguish byte values from 8-bit unsigned

	case scanner.Int, '(':
		p.back()
		x := int64(p.expr())
		if p.arch.Family == sys.ARM64 {
			if x >= 64 {
				p.errorf("register shift count too large: %s", str)
			}
			count = int16((x & 63) << 10)
		} else {
			if x >= 32 {
				p.errorf("register shift count too large: %s", str)
			}
			count = int16((x & 31) << 7)
		}
	default:
		p.errorf("unexpected %s in register shift", tok.String())
	}

	//go:cgo_import_dynamic _ _ "libpthread.so.0"
	//go:cgo_import_dynamic _ _ "libc.so.6"

In the end, the compiled Go package, which will eventually be
presented to cmd/link as part of a larger program, contains:

	_go_.o        # gc-compiled object for _cgo_gotypes.go, _cgo_import.go, *.cgo1.go
	_all.o        # gcc-compiled object for _cgo_export.c, *.cgo2.c