diff options
Diffstat (limited to 'vendor/github.com/shazow/ssh-chat/sshd/terminal/util.go')
-rw-r--r-- | vendor/github.com/shazow/ssh-chat/sshd/terminal/util.go | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/vendor/github.com/shazow/ssh-chat/sshd/terminal/util.go b/vendor/github.com/shazow/ssh-chat/sshd/terminal/util.go new file mode 100644 index 00000000..39110408 --- /dev/null +++ b/vendor/github.com/shazow/ssh-chat/sshd/terminal/util.go @@ -0,0 +1,114 @@ +// 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 aix 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 "golang.org/x/crypto/ssh/terminal" + +import ( + "golang.org/x/sys/unix" +) + +// State contains the state of a terminal. +type State struct { + termios unix.Termios +} + +// IsTerminal returns whether the given file descriptor is a terminal. +func IsTerminal(fd int) bool { + _, err := unix.IoctlGetTermios(fd, ioctlReadTermios) + return err == nil +} + +// 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) { + termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios) + if err != nil { + return nil, err + } + + oldState := State{termios: *termios} + + // This attempts to replicate the behaviour documented for cfmakeraw in + // the termios(3) manpage. + 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, ioctlWriteTermios, termios); err != nil { + 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) { + termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios) + if err != nil { + return nil, err + } + + return &State{termios: *termios}, nil +} + +// Restore restores the terminal connected to the given file descriptor to a +// previous state. +func Restore(fd int, state *State) error { + return unix.IoctlSetTermios(fd, ioctlWriteTermios, &state.termios) +} + +// GetSize returns the dimensions of the given terminal. +func GetSize(fd int) (width, height int, err error) { + ws, err := unix.IoctlGetWinsize(fd, unix.TIOCGWINSZ) + if err != nil { + return -1, -1, err + } + return int(ws.Col), int(ws.Row), nil +} + +// passwordReader is an io.Reader that reads from a specific file descriptor. +type passwordReader int + +func (r passwordReader) Read(buf []byte) (int, error) { + return unix.Read(int(r), buf) +} + +// 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) { + termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios) + if err != nil { + return nil, err + } + + newState := *termios + newState.Lflag &^= unix.ECHO + newState.Lflag |= unix.ICANON | unix.ISIG + newState.Iflag |= unix.ICRNL + if err := unix.IoctlSetTermios(fd, ioctlWriteTermios, &newState); err != nil { + return nil, err + } + + defer unix.IoctlSetTermios(fd, ioctlWriteTermios, termios) + + return readPasswordLine(passwordReader(fd)) +} |