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// +build zos,s390x
7
8package unix
9
10import (
11	"runtime"
12	"unsafe"
13)
14
15// ioctl itself should not be exposed directly, but additional get/set
16// functions for specific types are permissible.
17
18// IoctlSetInt performs an ioctl operation which sets an integer value
19// on fd, using the specified request number.
20func IoctlSetInt(fd int, req uint, value int) error {
21	return ioctl(fd, req, uintptr(value))
22}
23
24// IoctlSetWinsize performs an ioctl on fd with a *Winsize argument.
25//
26// To change fd's window size, the req argument should be TIOCSWINSZ.
27func IoctlSetWinsize(fd int, req uint, value *Winsize) error {
28	// TODO: if we get the chance, remove the req parameter and
29	// hardcode TIOCSWINSZ.
30	err := ioctl(fd, req, uintptr(unsafe.Pointer(value)))
31	runtime.KeepAlive(value)
32	return err
33}
34
35// IoctlSetTermios performs an ioctl on fd with a *Termios.
36//
37// The req value is expected to be TCSETS, TCSETSW, or TCSETSF
38func IoctlSetTermios(fd int, req uint, value *Termios) error {
39	if (req != TCSETS) && (req != TCSETSW) && (req != TCSETSF) {
40		return ENOSYS
41	}
42	err := Tcsetattr(fd, int(req), value)
43	runtime.KeepAlive(value)
44	return err
45}
46
47// IoctlGetInt performs an ioctl operation which gets an integer value
48// from fd, using the specified request number.
49//
50// A few ioctl requests use the return value as an output parameter;
51// for those, IoctlRetInt should be used instead of this function.
52func IoctlGetInt(fd int, req uint) (int, error) {
53	var value int
54	err := ioctl(fd, req, uintptr(unsafe.Pointer(&value)))
55	return value, err
56}
57
58func IoctlGetWinsize(fd int, req uint) (*Winsize, error) {
59	var value Winsize
60	err := ioctl(fd, req, uintptr(unsafe.Pointer(&value)))
61	return &value, err
62}
63
64// IoctlGetTermios performs an ioctl on fd with a *Termios.
65//
66// The req value is expected to be TCGETS
67func IoctlGetTermios(fd int, req uint) (*Termios, error) {
68	var value Termios
69	if req != TCGETS {
70		return &value, ENOSYS
71	}
72	err := Tcgetattr(fd, &value)
73	return &value, err
74}
75