return client, tempFile, server, data, hook
}

func hookSendFile(t *testing.T) *sendFileHook {
	h := new(sendFileHook)
	orig := poll.TestHookDidSendFile
	t.Cleanup(func() {
		poll.TestHookDidSendFile = orig
	})
	poll.TestHookDidSendFile = func(dstFD *poll.FD, src int, written int64, err error, handled bool) {
		h.called = true
		h.dstfd = dstFD.Sysfd
		h.srcfd = src
		h.written = written

// Copyright 2024 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package poll

// at a time.
const maxSendfileSize int = 4 << 20

// SendFile wraps the sendfile system call.
func SendFile(dstFD *FD, src int, remain int64) (written int64, err error, handled bool) {
	defer func() {
		TestHookDidSendFile(dstFD, src, written, err, handled)
	}()
	if err := dstFD.writeLock(); err != nil {
		return 0, err, false
	}
	defer dstFD.writeUnlock()

	if err := dstFD.pd.prepareWrite(dstFD.isFile); err != nil {

// at a time.
const maxSendfileSize int = 4 << 20

// SendFile wraps the sendfile system call.
func SendFile(dstFD *FD, src int, pos, remain int64) (written int64, err error, handled bool) {
	defer func() {
		TestHookDidSendFile(dstFD, src, written, err, handled)
	}()
	if err := dstFD.writeLock(); err != nil {
		return 0, err, false
	}
	defer dstFD.writeUnlock()

	if err := dstFD.pd.prepareWrite(dstFD.isFile); err != nil {

package poll

import (
	"io"
	"syscall"
)

// SendFile wraps the TransmitFile call.
func SendFile(fd *FD, src syscall.Handle, n int64) (written int64, err error) {
	defer func() {
		TestHookDidSendFile(fd, 0, written, err, written > 0)
	}()
	if fd.kind == kindPipe {
		// TransmitFile does not work with pipes
		return 0, syscall.ESPIPE
	}
	if ft, _ := syscall.GetFileType(src); ft == syscall.FILE_TYPE_PIPE {

// at a time.
const maxSendfileSize int = 4 << 20

// SendFile wraps the sendfile system call.
func SendFile(dstFD *FD, src int, pos, remain int64) (written int64, err error, handled bool) {
	defer func() {
		TestHookDidSendFile(dstFD, src, written, err, handled)
	}()
	if err := dstFD.writeLock(); err != nil {
		return 0, err, false
	}
	defer dstFD.writeUnlock()

	if err := dstFD.pd.prepareWrite(dstFD.isFile); err != nil {

	t.Helper()
	if !supportsSendfile {
		f()
		return
	}
	orig := poll.TestHookDidSendFile
	defer func() {
		poll.TestHookDidSendFile = orig
	}()
	var (
		called     bool
		gotHandled bool
		gotFD      *poll.FD
	)
	poll.TestHookDidSendFile = func(dstFD *poll.FD, src int, written int64, err error, handled bool) {
		if called {