syscall to set raw-mode-input terminal in Go (Posix/Windows)

raw_mode_posix.go

// +build darwin linux

package main

import (
    "os"
    "syscall"
    "unsafe"
)

func getTermios(fd uintptr) *syscall.Termios {
    var t syscall.Termios
    _, _, err := syscall.Syscall6(
        syscall.SYS_IOCTL,
        os.Stdin.Fd(),
        syscall.TCGETS,
        uintptr(unsafe.Pointer(&t)),
        0, 0, 0)

    if err != 0 {
        panic("err")
    }

    return &t
}

func setTermios(fd uintptr, term *syscall.Termios) {
    _, _, err := syscall.Syscall6(
        syscall.SYS_IOCTL,
        os.Stdin.Fd(),
        syscall.TCSETS,
        uintptr(unsafe.Pointer(term)),
        0,0,0)
    if err != 0 {
        panic("err")
    }
}

func setRaw(term *syscall.Termios) {
    // This attempts to replicate the behaviour documented for cfmakeraw in
    // the termios(3) manpage.
    term.Iflag &^= syscall.IGNBRK | syscall.BRKINT | syscall.PARMRK | syscall.ISTRIP | syscall.INLCR | syscall.IGNCR | syscall.ICRNL | syscall.IXON
    // newState.Oflag &^= syscall.OPOST
    term.Lflag &^= syscall.ECHO | syscall.ECHONL | syscall.ICANON | syscall.ISIG | syscall.IEXTEN
    term.Cflag &^= syscall.CSIZE | syscall.PARENB
    term.Cflag |= syscall.CS8

    term.Cc[syscall.VMIN] = 1
    term.Cc[syscall.VTIME] = 0
}

func main() {
    t := getTermios(os.Stdin.Fd())

    origin := *t
    defer func() {
        setTermios(os.Stdin.Fd(), &origin)
    }()

    setRaw(t)
    setTermios(os.Stdin.Fd(), t)

    for i := 0; i < 3; i++{
        buf := make([]byte, 1)
        syscall.Read(0, buf)
        println(buf[0])
    }
}

raw_mode_windows.go

package main

import (
	"os"
	"syscall"
	"unsafe"
)

var kernel32 = syscall.NewLazyDLL("kernel32.dll")

var (
	procGetConsoleMode             = kernel32.NewProc("GetConsoleMode")
	procSetConsoleMode             = kernel32.NewProc("SetConsoleMode")
)

const (
	enableLineInput       = 2
	enableEchoInput       = 4
	enableProcessedInput  = 1
	enableWindowInput     = 8
	enableMouseInput      = 16
	enableInsertMode      = 32
	enableQuickEditMode   = 64
	enableExtendedFlags   = 128
	enableAutoPosition    = 256
	enableProcessedOutput = 1
	enableWrapAtEolOutput = 2
)

func getTermMode(fd uintptr) uint32 {
	var mode uint32
	_, _, err := syscall.Syscall(
		procGetConsoleMode.Addr(),
		2,
		fd,
		uintptr(unsafe.Pointer(&mode)),
		0)
	if err != 0 {
		panic("err")
	}

	return mode
}

func setTermMode(fd uintptr, mode uint32) {
	_, _, err := syscall.Syscall(
		procSetConsoleMode.Addr(),
		2,
		fd,
		uintptr(mode),
		0)
	if err != 0 {
		panic("err")
	}
}

func main() {
	originMode := getTermMode(os.Stdin.Fd())

	defer func(m uint32) {
		setTermMode(os.Stdin.Fd(), m)
	}(originMode)

	originMode &^= (enableEchoInput | enableProcessedInput | enableLineInput | enableProcessedOutput)
	setTermMode(os.Stdin.Fd(), originMode)

	for i := 0; i < 3; i++{
		buf := make([]byte, 1)
		syscall.Read(syscall.Handle(os.Stdin.Fd()), buf)
		println(buf[0])
	}
}