128 lines
3.9 KiB
Go
Executable file
128 lines
3.9 KiB
Go
Executable file
// Copyright 2011 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.
|
|
|
|
// +build darwin dragonfly freebsd linux,!appengine netbsd openbsd
|
|
|
|
// Package terminal provides support functions for dealing with terminals, as
|
|
// commonly found on UNIX systems.
|
|
//
|
|
// Putting a terminal into raw mode is the most common requirement:
|
|
//
|
|
// oldState, err := terminal.MakeRaw(0)
|
|
// if err != nil {
|
|
// panic(err)
|
|
// }
|
|
// defer terminal.Restore(0, oldState)
|
|
package terminal
|
|
|
|
import (
|
|
"io"
|
|
"syscall"
|
|
"unsafe"
|
|
)
|
|
|
|
// State contains the state of a terminal.
|
|
type State struct {
|
|
termios syscall.Termios
|
|
}
|
|
|
|
// IsTerminal returns true if the given file descriptor is a terminal.
|
|
func IsTerminal(fd int) bool {
|
|
var termios syscall.Termios
|
|
_, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlReadTermios, uintptr(unsafe.Pointer(&termios)), 0, 0, 0)
|
|
return err == 0
|
|
}
|
|
|
|
// MakeRaw put the terminal connected to the given file descriptor into raw
|
|
// mode and returns the previous state of the terminal so that it can be
|
|
// restored.
|
|
func MakeRaw(fd int) (*State, error) {
|
|
var oldState State
|
|
if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlReadTermios, uintptr(unsafe.Pointer(&oldState.termios)), 0, 0, 0); err != 0 {
|
|
return nil, err
|
|
}
|
|
|
|
newState := oldState.termios
|
|
newState.Iflag &^= syscall.ISTRIP | syscall.INLCR | syscall.ICRNL | syscall.IGNCR | syscall.IXON | syscall.IXOFF
|
|
newState.Lflag &^= syscall.ECHO | syscall.ICANON | syscall.ISIG
|
|
if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&newState)), 0, 0, 0); err != 0 {
|
|
return nil, err
|
|
}
|
|
|
|
return &oldState, nil
|
|
}
|
|
|
|
// GetState returns the current state of a terminal which may be useful to
|
|
// restore the terminal after a signal.
|
|
func GetState(fd int) (*State, error) {
|
|
var oldState State
|
|
if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlReadTermios, uintptr(unsafe.Pointer(&oldState.termios)), 0, 0, 0); err != 0 {
|
|
return nil, err
|
|
}
|
|
|
|
return &oldState, nil
|
|
}
|
|
|
|
// Restore restores the terminal connected to the given file descriptor to a
|
|
// previous state.
|
|
func Restore(fd int, state *State) error {
|
|
_, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&state.termios)), 0, 0, 0)
|
|
return err
|
|
}
|
|
|
|
// GetSize returns the dimensions of the given terminal.
|
|
func GetSize(fd int) (width, height int, err error) {
|
|
var dimensions [4]uint16
|
|
|
|
if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), uintptr(syscall.TIOCGWINSZ), uintptr(unsafe.Pointer(&dimensions)), 0, 0, 0); err != 0 {
|
|
return -1, -1, err
|
|
}
|
|
return int(dimensions[1]), int(dimensions[0]), nil
|
|
}
|
|
|
|
// ReadPassword reads a line of input from a terminal without local echo. This
|
|
// is commonly used for inputting passwords and other sensitive data. The slice
|
|
// returned does not include the \n.
|
|
func ReadPassword(fd int) ([]byte, error) {
|
|
var oldState syscall.Termios
|
|
if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlReadTermios, uintptr(unsafe.Pointer(&oldState)), 0, 0, 0); err != 0 {
|
|
return nil, err
|
|
}
|
|
|
|
newState := oldState
|
|
newState.Lflag &^= syscall.ECHO
|
|
newState.Lflag |= syscall.ICANON | syscall.ISIG
|
|
newState.Iflag |= syscall.ICRNL
|
|
if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&newState)), 0, 0, 0); err != 0 {
|
|
return nil, err
|
|
}
|
|
|
|
defer func() {
|
|
syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&oldState)), 0, 0, 0)
|
|
}()
|
|
|
|
var buf [16]byte
|
|
var ret []byte
|
|
for {
|
|
n, err := syscall.Read(fd, buf[:])
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if n == 0 {
|
|
if len(ret) == 0 {
|
|
return nil, io.EOF
|
|
}
|
|
break
|
|
}
|
|
if buf[n-1] == '\n' {
|
|
n--
|
|
}
|
|
ret = append(ret, buf[:n]...)
|
|
if n < len(buf) {
|
|
break
|
|
}
|
|
}
|
|
|
|
return ret, nil
|
|
}
|