| // Copyright 2019 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 term |
| |
| import ( |
| "io" |
| "syscall" |
| |
| "golang.org/x/sys/unix" |
| ) |
| |
| // State contains the state of a terminal. |
| type state struct { |
| termios unix.Termios |
| } |
| |
| func isTerminal(fd int) bool { |
| _, err := unix.IoctlGetTermio(fd, unix.TCGETA) |
| return err == nil |
| } |
| |
| func readPassword(fd int) ([]byte, error) { |
| // see also: http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libast/common/uwin/getpass.c |
| val, err := unix.IoctlGetTermios(fd, unix.TCGETS) |
| if err != nil { |
| return nil, err |
| } |
| oldState := *val |
| |
| newState := oldState |
| newState.Lflag &^= syscall.ECHO |
| newState.Lflag |= syscall.ICANON | syscall.ISIG |
| newState.Iflag |= syscall.ICRNL |
| err = unix.IoctlSetTermios(fd, unix.TCSETS, &newState) |
| if err != nil { |
| return nil, err |
| } |
| |
| defer unix.IoctlSetTermios(fd, unix.TCSETS, &oldState) |
| |
| 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 |
| } |
| |
| func makeRaw(fd int) (*State, error) { |
| // see http://cr.illumos.org/~webrev/andy_js/1060/ |
| termios, err := unix.IoctlGetTermios(fd, unix.TCGETS) |
| if err != nil { |
| return nil, err |
| } |
| |
| oldState := State{state{termios: *termios}} |
| |
| termios.Iflag &^= unix.IGNBRK | unix.BRKINT | unix.PARMRK | unix.ISTRIP | unix.INLCR | unix.IGNCR | unix.ICRNL | unix.IXON |
| termios.Oflag &^= unix.OPOST |
| termios.Lflag &^= unix.ECHO | unix.ECHONL | unix.ICANON | unix.ISIG | unix.IEXTEN |
| termios.Cflag &^= unix.CSIZE | unix.PARENB |
| termios.Cflag |= unix.CS8 |
| termios.Cc[unix.VMIN] = 1 |
| termios.Cc[unix.VTIME] = 0 |
| |
| if err := unix.IoctlSetTermios(fd, unix.TCSETS, termios); err != nil { |
| return nil, err |
| } |
| |
| return &oldState, nil |
| } |
| |
| func restore(fd int, oldState *State) error { |
| return unix.IoctlSetTermios(fd, unix.TCSETS, &oldState.termios) |
| } |
| |
| func getState(fd int) (*State, error) { |
| termios, err := unix.IoctlGetTermios(fd, unix.TCGETS) |
| if err != nil { |
| return nil, err |
| } |
| |
| return &State{state{termios: *termios}}, nil |
| } |
| |
| func getSize(fd int) (width, height int, err error) { |
| ws, err := unix.IoctlGetWinsize(fd, unix.TIOCGWINSZ) |
| if err != nil { |
| return 0, 0, err |
| } |
| return int(ws.Col), int(ws.Row), nil |
| } |