1// Copyright 2020 The Go Authors. All rights reserved.
 2// Use of this source code is governed by a BSD-style
 3// license that can be found in the LICENSE file.
 4
 5//go:build zos && s390x
 6
 7package unix
 8
 9import (
10	"runtime"
11	"unsafe"
12)
13
14// ioctl itself should not be exposed directly, but additional get/set
15// functions for specific types are permissible.
16
17// IoctlSetInt performs an ioctl operation which sets an integer value
18// on fd, using the specified request number.
19func IoctlSetInt(fd int, req int, value int) error {
20	return ioctl(fd, req, uintptr(value))
21}
22
23// IoctlSetWinsize performs an ioctl on fd with a *Winsize argument.
24//
25// To change fd's window size, the req argument should be TIOCSWINSZ.
26func IoctlSetWinsize(fd int, req int, value *Winsize) error {
27	// TODO: if we get the chance, remove the req parameter and
28	// hardcode TIOCSWINSZ.
29	return ioctlPtr(fd, req, unsafe.Pointer(value))
30}
31
32// IoctlSetTermios performs an ioctl on fd with a *Termios.
33//
34// The req value is expected to be TCSETS, TCSETSW, or TCSETSF
35func IoctlSetTermios(fd int, req int, value *Termios) error {
36	if (req != TCSETS) && (req != TCSETSW) && (req != TCSETSF) {
37		return ENOSYS
38	}
39	err := Tcsetattr(fd, int(req), value)
40	runtime.KeepAlive(value)
41	return err
42}
43
44// IoctlGetInt performs an ioctl operation which gets an integer value
45// from fd, using the specified request number.
46//
47// A few ioctl requests use the return value as an output parameter;
48// for those, IoctlRetInt should be used instead of this function.
49func IoctlGetInt(fd int, req int) (int, error) {
50	var value int
51	err := ioctlPtr(fd, req, unsafe.Pointer(&value))
52	return value, err
53}
54
55func IoctlGetWinsize(fd int, req int) (*Winsize, error) {
56	var value Winsize
57	err := ioctlPtr(fd, req, unsafe.Pointer(&value))
58	return &value, err
59}
60
61// IoctlGetTermios performs an ioctl on fd with a *Termios.
62//
63// The req value is expected to be TCGETS
64func IoctlGetTermios(fd int, req int) (*Termios, error) {
65	var value Termios
66	if req != TCGETS {
67		return &value, ENOSYS
68	}
69	err := Tcgetattr(fd, &value)
70	return &value, err
71}