+++ /dev/null
-// 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.
-
-package terminal
-
-import (
- "io"
- "sync"
-)
-
-// EscapeCodes contains escape sequences that can be written to the terminal in
-// order to achieve different styles of text.
-type EscapeCodes struct {
- // Foreground colors
- Black, Red, Green, Yellow, Blue, Magenta, Cyan, White []byte
-
- // Reset all attributes
- Reset []byte
-}
-
-var vt100EscapeCodes = EscapeCodes{
- Black: []byte{keyEscape, '[', '3', '0', 'm'},
- Red: []byte{keyEscape, '[', '3', '1', 'm'},
- Green: []byte{keyEscape, '[', '3', '2', 'm'},
- Yellow: []byte{keyEscape, '[', '3', '3', 'm'},
- Blue: []byte{keyEscape, '[', '3', '4', 'm'},
- Magenta: []byte{keyEscape, '[', '3', '5', 'm'},
- Cyan: []byte{keyEscape, '[', '3', '6', 'm'},
- White: []byte{keyEscape, '[', '3', '7', 'm'},
-
- Reset: []byte{keyEscape, '[', '0', 'm'},
-}
-
-// Terminal contains the state for running a VT100 terminal that is capable of
-// reading lines of input.
-type Terminal struct {
- // AutoCompleteCallback, if non-null, is called for each keypress
- // with the full input line and the current position of the cursor.
- // If it returns a nil newLine, the key press is processed normally.
- // Otherwise it returns a replacement line and the new cursor position.
- AutoCompleteCallback func(line []byte, pos, key int) (newLine []byte, newPos int)
-
- // Escape contains a pointer to the escape codes for this terminal.
- // It's always a valid pointer, although the escape codes themselves
- // may be empty if the terminal doesn't support them.
- Escape *EscapeCodes
-
- // lock protects the terminal and the state in this object from
- // concurrent processing of a key press and a Write() call.
- lock sync.Mutex
-
- c io.ReadWriter
- prompt string
-
- // line is the current line being entered.
- line []byte
- // pos is the logical position of the cursor in line
- pos int
- // echo is true if local echo is enabled
- echo bool
-
- // cursorX contains the current X value of the cursor where the left
- // edge is 0. cursorY contains the row number where the first row of
- // the current line is 0.
- cursorX, cursorY int
- // maxLine is the greatest value of cursorY so far.
- maxLine int
-
- termWidth, termHeight int
-
- // outBuf contains the terminal data to be sent.
- outBuf []byte
- // remainder contains the remainder of any partial key sequences after
- // a read. It aliases into inBuf.
- remainder []byte
- inBuf [256]byte
-}
-
-// NewTerminal runs a VT100 terminal on the given ReadWriter. If the ReadWriter is
-// a local terminal, that terminal must first have been put into raw mode.
-// prompt is a string that is written at the start of each input line (i.e.
-// "> ").
-func NewTerminal(c io.ReadWriter, prompt string) *Terminal {
- return &Terminal{
- Escape: &vt100EscapeCodes,
- c: c,
- prompt: prompt,
- termWidth: 80,
- termHeight: 24,
- echo: true,
- }
-}
-
-const (
- keyCtrlD = 4
- keyEnter = '\r'
- keyEscape = 27
- keyBackspace = 127
- keyUnknown = 256 + iota
- keyUp
- keyDown
- keyLeft
- keyRight
- keyAltLeft
- keyAltRight
-)
-
-// bytesToKey tries to parse a key sequence from b. If successful, it returns
-// the key and the remainder of the input. Otherwise it returns -1.
-func bytesToKey(b []byte) (int, []byte) {
- if len(b) == 0 {
- return -1, nil
- }
-
- if b[0] != keyEscape {
- return int(b[0]), b[1:]
- }
-
- if len(b) >= 3 && b[0] == keyEscape && b[1] == '[' {
- switch b[2] {
- case 'A':
- return keyUp, b[3:]
- case 'B':
- return keyDown, b[3:]
- case 'C':
- return keyRight, b[3:]
- case 'D':
- return keyLeft, b[3:]
- }
- }
-
- if len(b) >= 6 && b[0] == keyEscape && b[1] == '[' && b[2] == '1' && b[3] == ';' && b[4] == '3' {
- switch b[5] {
- case 'C':
- return keyAltRight, b[6:]
- case 'D':
- return keyAltLeft, b[6:]
- }
- }
-
- // If we get here then we have a key that we don't recognise, or a
- // partial sequence. It's not clear how one should find the end of a
- // sequence without knowing them all, but it seems that [a-zA-Z] only
- // appears at the end of a sequence.
- for i, c := range b[0:] {
- if c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' {
- return keyUnknown, b[i+1:]
- }
- }
-
- return -1, b
-}
-
-// queue appends data to the end of t.outBuf
-func (t *Terminal) queue(data []byte) {
- t.outBuf = append(t.outBuf, data...)
-}
-
-var eraseUnderCursor = []byte{' ', keyEscape, '[', 'D'}
-var space = []byte{' '}
-
-func isPrintable(key int) bool {
- return key >= 32 && key < 127
-}
-
-// moveCursorToPos appends data to t.outBuf which will move the cursor to the
-// given, logical position in the text.
-func (t *Terminal) moveCursorToPos(pos int) {
- if !t.echo {
- return
- }
-
- x := len(t.prompt) + pos
- y := x / t.termWidth
- x = x % t.termWidth
-
- up := 0
- if y < t.cursorY {
- up = t.cursorY - y
- }
-
- down := 0
- if y > t.cursorY {
- down = y - t.cursorY
- }
-
- left := 0
- if x < t.cursorX {
- left = t.cursorX - x
- }
-
- right := 0
- if x > t.cursorX {
- right = x - t.cursorX
- }
-
- t.cursorX = x
- t.cursorY = y
- t.move(up, down, left, right)
-}
-
-func (t *Terminal) move(up, down, left, right int) {
- movement := make([]byte, 3*(up+down+left+right))
- m := movement
- for i := 0; i < up; i++ {
- m[0] = keyEscape
- m[1] = '['
- m[2] = 'A'
- m = m[3:]
- }
- for i := 0; i < down; i++ {
- m[0] = keyEscape
- m[1] = '['
- m[2] = 'B'
- m = m[3:]
- }
- for i := 0; i < left; i++ {
- m[0] = keyEscape
- m[1] = '['
- m[2] = 'D'
- m = m[3:]
- }
- for i := 0; i < right; i++ {
- m[0] = keyEscape
- m[1] = '['
- m[2] = 'C'
- m = m[3:]
- }
-
- t.queue(movement)
-}
-
-func (t *Terminal) clearLineToRight() {
- op := []byte{keyEscape, '[', 'K'}
- t.queue(op)
-}
-
-const maxLineLength = 4096
-
-// handleKey processes the given key and, optionally, returns a line of text
-// that the user has entered.
-func (t *Terminal) handleKey(key int) (line string, ok bool) {
- switch key {
- case keyBackspace:
- if t.pos == 0 {
- return
- }
- t.pos--
- t.moveCursorToPos(t.pos)
-
- copy(t.line[t.pos:], t.line[1+t.pos:])
- t.line = t.line[:len(t.line)-1]
- if t.echo {
- t.writeLine(t.line[t.pos:])
- }
- t.queue(eraseUnderCursor)
- t.moveCursorToPos(t.pos)
- case keyAltLeft:
- // move left by a word.
- if t.pos == 0 {
- return
- }
- t.pos--
- for t.pos > 0 {
- if t.line[t.pos] != ' ' {
- break
- }
- t.pos--
- }
- for t.pos > 0 {
- if t.line[t.pos] == ' ' {
- t.pos++
- break
- }
- t.pos--
- }
- t.moveCursorToPos(t.pos)
- case keyAltRight:
- // move right by a word.
- for t.pos < len(t.line) {
- if t.line[t.pos] == ' ' {
- break
- }
- t.pos++
- }
- for t.pos < len(t.line) {
- if t.line[t.pos] != ' ' {
- break
- }
- t.pos++
- }
- t.moveCursorToPos(t.pos)
- case keyLeft:
- if t.pos == 0 {
- return
- }
- t.pos--
- t.moveCursorToPos(t.pos)
- case keyRight:
- if t.pos == len(t.line) {
- return
- }
- t.pos++
- t.moveCursorToPos(t.pos)
- case keyEnter:
- t.moveCursorToPos(len(t.line))
- t.queue([]byte("\r\n"))
- line = string(t.line)
- ok = true
- t.line = t.line[:0]
- t.pos = 0
- t.cursorX = 0
- t.cursorY = 0
- t.maxLine = 0
- default:
- if t.AutoCompleteCallback != nil {
- t.lock.Unlock()
- newLine, newPos := t.AutoCompleteCallback(t.line, t.pos, key)
- t.lock.Lock()
-
- if newLine != nil {
- if t.echo {
- t.moveCursorToPos(0)
- t.writeLine(newLine)
- for i := len(newLine); i < len(t.line); i++ {
- t.writeLine(space)
- }
- t.moveCursorToPos(newPos)
- }
- t.line = newLine
- t.pos = newPos
- return
- }
- }
- if !isPrintable(key) {
- return
- }
- if len(t.line) == maxLineLength {
- return
- }
- if len(t.line) == cap(t.line) {
- newLine := make([]byte, len(t.line), 2*(1+len(t.line)))
- copy(newLine, t.line)
- t.line = newLine
- }
- t.line = t.line[:len(t.line)+1]
- copy(t.line[t.pos+1:], t.line[t.pos:])
- t.line[t.pos] = byte(key)
- if t.echo {
- t.writeLine(t.line[t.pos:])
- }
- t.pos++
- t.moveCursorToPos(t.pos)
- }
- return
-}
-
-func (t *Terminal) writeLine(line []byte) {
- for len(line) != 0 {
- remainingOnLine := t.termWidth - t.cursorX
- todo := len(line)
- if todo > remainingOnLine {
- todo = remainingOnLine
- }
- t.queue(line[:todo])
- t.cursorX += todo
- line = line[todo:]
-
- if t.cursorX == t.termWidth {
- t.cursorX = 0
- t.cursorY++
- if t.cursorY > t.maxLine {
- t.maxLine = t.cursorY
- }
- }
- }
-}
-
-func (t *Terminal) Write(buf []byte) (n int, err error) {
- t.lock.Lock()
- defer t.lock.Unlock()
-
- if t.cursorX == 0 && t.cursorY == 0 {
- // This is the easy case: there's nothing on the screen that we
- // have to move out of the way.
- return t.c.Write(buf)
- }
-
- // We have a prompt and possibly user input on the screen. We
- // have to clear it first.
- t.move(0 /* up */, 0 /* down */, t.cursorX /* left */, 0 /* right */)
- t.cursorX = 0
- t.clearLineToRight()
-
- for t.cursorY > 0 {
- t.move(1 /* up */, 0, 0, 0)
- t.cursorY--
- t.clearLineToRight()
- }
-
- if _, err = t.c.Write(t.outBuf); err != nil {
- return
- }
- t.outBuf = t.outBuf[:0]
-
- if n, err = t.c.Write(buf); err != nil {
- return
- }
-
- t.queue([]byte(t.prompt))
- chars := len(t.prompt)
- if t.echo {
- t.queue(t.line)
- chars += len(t.line)
- }
- t.cursorX = chars % t.termWidth
- t.cursorY = chars / t.termWidth
- t.moveCursorToPos(t.pos)
-
- if _, err = t.c.Write(t.outBuf); err != nil {
- return
- }
- t.outBuf = t.outBuf[:0]
- return
-}
-
-// ReadPassword temporarily changes the prompt and reads a password, without
-// echo, from the terminal.
-func (t *Terminal) ReadPassword(prompt string) (line string, err error) {
- t.lock.Lock()
- defer t.lock.Unlock()
-
- oldPrompt := t.prompt
- t.prompt = prompt
- t.echo = false
-
- line, err = t.readLine()
-
- t.prompt = oldPrompt
- t.echo = true
-
- return
-}
-
-// ReadLine returns a line of input from the terminal.
-func (t *Terminal) ReadLine() (line string, err error) {
- t.lock.Lock()
- defer t.lock.Unlock()
-
- return t.readLine()
-}
-
-func (t *Terminal) readLine() (line string, err error) {
- // t.lock must be held at this point
-
- if t.cursorX == 0 && t.cursorY == 0 {
- t.writeLine([]byte(t.prompt))
- t.c.Write(t.outBuf)
- t.outBuf = t.outBuf[:0]
- }
-
- for {
- rest := t.remainder
- lineOk := false
- for !lineOk {
- var key int
- key, rest = bytesToKey(rest)
- if key < 0 {
- break
- }
- if key == keyCtrlD {
- return "", io.EOF
- }
- line, lineOk = t.handleKey(key)
- }
- if len(rest) > 0 {
- n := copy(t.inBuf[:], rest)
- t.remainder = t.inBuf[:n]
- } else {
- t.remainder = nil
- }
- t.c.Write(t.outBuf)
- t.outBuf = t.outBuf[:0]
- if lineOk {
- return
- }
-
- // t.remainder is a slice at the beginning of t.inBuf
- // containing a partial key sequence
- readBuf := t.inBuf[len(t.remainder):]
- var n int
-
- t.lock.Unlock()
- n, err = t.c.Read(readBuf)
- t.lock.Lock()
-
- if err != nil {
- return
- }
-
- t.remainder = t.inBuf[:n+len(t.remainder)]
- }
- panic("unreachable")
-}
-
-// SetPrompt sets the prompt to be used when reading subsequent lines.
-func (t *Terminal) SetPrompt(prompt string) {
- t.lock.Lock()
- defer t.lock.Unlock()
-
- t.prompt = prompt
-}
-
-func (t *Terminal) SetSize(width, height int) {
- t.lock.Lock()
- defer t.lock.Unlock()
-
- t.termWidth, t.termHeight = width, height
-}
+++ /dev/null
-// 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 linux
-
-// 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), uintptr(syscall.TCGETS), 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), uintptr(syscall.TCGETS), 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), uintptr(syscall.TCSETS), uintptr(unsafe.Pointer(&newState)), 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), uintptr(syscall.TCSETS), 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), uintptr(syscall.TCGETS), uintptr(unsafe.Pointer(&oldState)), 0, 0, 0); err != 0 {
- return nil, err
- }
-
- newState := oldState
- newState.Lflag &^= syscall.ECHO
- if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), uintptr(syscall.TCSETS), uintptr(unsafe.Pointer(&newState)), 0, 0, 0); err != 0 {
- return nil, err
- }
-
- defer func() {
- syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), uintptr(syscall.TCSETS), 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
-}