mirror of
https://github.com/cwinfo/matterbridge.git
synced 2024-11-15 14:30:26 +00:00
956 lines
22 KiB
Go
956 lines
22 KiB
Go
// 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 (
|
|
"bytes"
|
|
"io"
|
|
"sync"
|
|
"unicode/utf8"
|
|
)
|
|
|
|
// 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 (in
|
|
// bytes, as an index into |line|). If it returns ok=false, the key
|
|
// press is processed normally. Otherwise it returns a replacement line
|
|
// and the new cursor position.
|
|
AutoCompleteCallback func(line string, pos int, key rune) (newLine string, newPos int, ok bool)
|
|
|
|
// 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 []rune
|
|
|
|
// line is the current line being entered.
|
|
line []rune
|
|
// pos is the logical position of the cursor in line
|
|
pos int
|
|
// echo is true if local echo is enabled
|
|
echo bool
|
|
// pasteActive is true iff there is a bracketed paste operation in
|
|
// progress.
|
|
pasteActive 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
|
|
|
|
// history contains previously entered commands so that they can be
|
|
// accessed with the up and down keys.
|
|
history stRingBuffer
|
|
// historyIndex stores the currently accessed history entry, where zero
|
|
// means the immediately previous entry.
|
|
historyIndex int
|
|
// When navigating up and down the history it's possible to return to
|
|
// the incomplete, initial line. That value is stored in
|
|
// historyPending.
|
|
historyPending string
|
|
}
|
|
|
|
// 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: []rune(prompt),
|
|
termWidth: 80,
|
|
termHeight: 24,
|
|
echo: true,
|
|
historyIndex: -1,
|
|
}
|
|
}
|
|
|
|
const (
|
|
keyCtrlD = 4
|
|
keyCtrlU = 21
|
|
keyEnter = '\r'
|
|
keyEscape = 27
|
|
keyBackspace = 127
|
|
keyUnknown = 0xd800 /* UTF-16 surrogate area */ + iota
|
|
keyUp
|
|
keyDown
|
|
keyLeft
|
|
keyRight
|
|
keyAltLeft
|
|
keyAltRight
|
|
keyHome
|
|
keyEnd
|
|
keyDeleteWord
|
|
keyDeleteLine
|
|
keyClearScreen
|
|
keyPasteStart
|
|
keyPasteEnd
|
|
)
|
|
|
|
var (
|
|
crlf = []byte{'\r', '\n'}
|
|
pasteStart = []byte{keyEscape, '[', '2', '0', '0', '~'}
|
|
pasteEnd = []byte{keyEscape, '[', '2', '0', '1', '~'}
|
|
)
|
|
|
|
// bytesToKey tries to parse a key sequence from b. If successful, it returns
|
|
// the key and the remainder of the input. Otherwise it returns utf8.RuneError.
|
|
func bytesToKey(b []byte, pasteActive bool) (rune, []byte) {
|
|
if len(b) == 0 {
|
|
return utf8.RuneError, nil
|
|
}
|
|
|
|
if !pasteActive {
|
|
switch b[0] {
|
|
case 1: // ^A
|
|
return keyHome, b[1:]
|
|
case 5: // ^E
|
|
return keyEnd, b[1:]
|
|
case 8: // ^H
|
|
return keyBackspace, b[1:]
|
|
case 11: // ^K
|
|
return keyDeleteLine, b[1:]
|
|
case 12: // ^L
|
|
return keyClearScreen, b[1:]
|
|
case 23: // ^W
|
|
return keyDeleteWord, b[1:]
|
|
case 14: // ^N
|
|
return keyDown, b[1:]
|
|
case 16: // ^P
|
|
return keyUp, b[1:]
|
|
}
|
|
}
|
|
|
|
if b[0] != keyEscape {
|
|
if !utf8.FullRune(b) {
|
|
return utf8.RuneError, b
|
|
}
|
|
r, l := utf8.DecodeRune(b)
|
|
return r, b[l:]
|
|
}
|
|
|
|
if !pasteActive && 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:]
|
|
case 'H':
|
|
return keyHome, b[3:]
|
|
case 'F':
|
|
return keyEnd, b[3:]
|
|
}
|
|
}
|
|
|
|
if !pasteActive && 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 !pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteStart) {
|
|
return keyPasteStart, b[6:]
|
|
}
|
|
|
|
if pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteEnd) {
|
|
return keyPasteEnd, 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' || c == '~' {
|
|
return keyUnknown, b[i+1:]
|
|
}
|
|
}
|
|
|
|
return utf8.RuneError, b
|
|
}
|
|
|
|
// queue appends data to the end of t.outBuf
|
|
func (t *Terminal) queue(data []rune) {
|
|
t.outBuf = append(t.outBuf, []byte(string(data))...)
|
|
}
|
|
|
|
var eraseUnderCursor = []rune{' ', keyEscape, '[', 'D'}
|
|
var space = []rune{' '}
|
|
|
|
func isPrintable(key rune) bool {
|
|
isInSurrogateArea := key >= 0xd800 && key <= 0xdbff
|
|
return key >= 32 && !isInSurrogateArea
|
|
}
|
|
|
|
// 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 := visualLength(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([]rune, 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 := []rune{keyEscape, '[', 'K'}
|
|
t.queue(op)
|
|
}
|
|
|
|
const maxLineLength = 4096
|
|
|
|
func (t *Terminal) setLine(newLine []rune, newPos int) {
|
|
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
|
|
}
|
|
|
|
func (t *Terminal) advanceCursor(places int) {
|
|
t.cursorX += places
|
|
t.cursorY += t.cursorX / t.termWidth
|
|
if t.cursorY > t.maxLine {
|
|
t.maxLine = t.cursorY
|
|
}
|
|
t.cursorX = t.cursorX % t.termWidth
|
|
|
|
if places > 0 && t.cursorX == 0 {
|
|
// Normally terminals will advance the current position
|
|
// when writing a character. But that doesn't happen
|
|
// for the last character in a line. However, when
|
|
// writing a character (except a new line) that causes
|
|
// a line wrap, the position will be advanced two
|
|
// places.
|
|
//
|
|
// So, if we are stopping at the end of a line, we
|
|
// need to write a newline so that our cursor can be
|
|
// advanced to the next line.
|
|
t.outBuf = append(t.outBuf, '\r', '\n')
|
|
}
|
|
}
|
|
|
|
func (t *Terminal) eraseNPreviousChars(n int) {
|
|
if n == 0 {
|
|
return
|
|
}
|
|
|
|
if t.pos < n {
|
|
n = t.pos
|
|
}
|
|
t.pos -= n
|
|
t.moveCursorToPos(t.pos)
|
|
|
|
copy(t.line[t.pos:], t.line[n+t.pos:])
|
|
t.line = t.line[:len(t.line)-n]
|
|
if t.echo {
|
|
t.writeLine(t.line[t.pos:])
|
|
for i := 0; i < n; i++ {
|
|
t.queue(space)
|
|
}
|
|
t.advanceCursor(n)
|
|
t.moveCursorToPos(t.pos)
|
|
}
|
|
}
|
|
|
|
// countToLeftWord returns then number of characters from the cursor to the
|
|
// start of the previous word.
|
|
func (t *Terminal) countToLeftWord() int {
|
|
if t.pos == 0 {
|
|
return 0
|
|
}
|
|
|
|
pos := t.pos - 1
|
|
for pos > 0 {
|
|
if t.line[pos] != ' ' {
|
|
break
|
|
}
|
|
pos--
|
|
}
|
|
for pos > 0 {
|
|
if t.line[pos] == ' ' {
|
|
pos++
|
|
break
|
|
}
|
|
pos--
|
|
}
|
|
|
|
return t.pos - pos
|
|
}
|
|
|
|
// countToRightWord returns then number of characters from the cursor to the
|
|
// start of the next word.
|
|
func (t *Terminal) countToRightWord() int {
|
|
pos := t.pos
|
|
for pos < len(t.line) {
|
|
if t.line[pos] == ' ' {
|
|
break
|
|
}
|
|
pos++
|
|
}
|
|
for pos < len(t.line) {
|
|
if t.line[pos] != ' ' {
|
|
break
|
|
}
|
|
pos++
|
|
}
|
|
return pos - t.pos
|
|
}
|
|
|
|
// visualLength returns the number of visible glyphs in s.
|
|
func visualLength(runes []rune) int {
|
|
inEscapeSeq := false
|
|
length := 0
|
|
|
|
for _, r := range runes {
|
|
switch {
|
|
case inEscapeSeq:
|
|
if (r >= 'a' && r <= 'z') || (r >= 'A' && r <= 'Z') {
|
|
inEscapeSeq = false
|
|
}
|
|
case r == '\x1b':
|
|
inEscapeSeq = true
|
|
default:
|
|
length++
|
|
}
|
|
}
|
|
|
|
return length
|
|
}
|
|
|
|
// handleKey processes the given key and, optionally, returns a line of text
|
|
// that the user has entered.
|
|
func (t *Terminal) handleKey(key rune) (line string, ok bool) {
|
|
if t.pasteActive && key != keyEnter {
|
|
t.addKeyToLine(key)
|
|
return
|
|
}
|
|
|
|
switch key {
|
|
case keyBackspace:
|
|
if t.pos == 0 {
|
|
return
|
|
}
|
|
t.eraseNPreviousChars(1)
|
|
case keyAltLeft:
|
|
// move left by a word.
|
|
t.pos -= t.countToLeftWord()
|
|
t.moveCursorToPos(t.pos)
|
|
case keyAltRight:
|
|
// move right by a word.
|
|
t.pos += t.countToRightWord()
|
|
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 keyHome:
|
|
if t.pos == 0 {
|
|
return
|
|
}
|
|
t.pos = 0
|
|
t.moveCursorToPos(t.pos)
|
|
case keyEnd:
|
|
if t.pos == len(t.line) {
|
|
return
|
|
}
|
|
t.pos = len(t.line)
|
|
t.moveCursorToPos(t.pos)
|
|
case keyUp:
|
|
entry, ok := t.history.NthPreviousEntry(t.historyIndex + 1)
|
|
if !ok {
|
|
return "", false
|
|
}
|
|
if t.historyIndex == -1 {
|
|
t.historyPending = string(t.line)
|
|
}
|
|
t.historyIndex++
|
|
runes := []rune(entry)
|
|
t.setLine(runes, len(runes))
|
|
case keyDown:
|
|
switch t.historyIndex {
|
|
case -1:
|
|
return
|
|
case 0:
|
|
runes := []rune(t.historyPending)
|
|
t.setLine(runes, len(runes))
|
|
t.historyIndex--
|
|
default:
|
|
entry, ok := t.history.NthPreviousEntry(t.historyIndex - 1)
|
|
if ok {
|
|
t.historyIndex--
|
|
runes := []rune(entry)
|
|
t.setLine(runes, len(runes))
|
|
}
|
|
}
|
|
case keyEnter:
|
|
t.moveCursorToPos(len(t.line))
|
|
t.queue([]rune("\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
|
|
case keyDeleteWord:
|
|
// Delete zero or more spaces and then one or more characters.
|
|
t.eraseNPreviousChars(t.countToLeftWord())
|
|
case keyDeleteLine:
|
|
// Delete everything from the current cursor position to the
|
|
// end of line.
|
|
for i := t.pos; i < len(t.line); i++ {
|
|
t.queue(space)
|
|
t.advanceCursor(1)
|
|
}
|
|
t.line = t.line[:t.pos]
|
|
t.moveCursorToPos(t.pos)
|
|
case keyCtrlD:
|
|
// Erase the character under the current position.
|
|
// The EOF case when the line is empty is handled in
|
|
// readLine().
|
|
if t.pos < len(t.line) {
|
|
t.pos++
|
|
t.eraseNPreviousChars(1)
|
|
}
|
|
case keyCtrlU:
|
|
t.eraseNPreviousChars(t.pos)
|
|
case keyClearScreen:
|
|
// Erases the screen and moves the cursor to the home position.
|
|
t.queue([]rune("\x1b[2J\x1b[H"))
|
|
t.queue(t.prompt)
|
|
t.cursorX, t.cursorY = 0, 0
|
|
t.advanceCursor(visualLength(t.prompt))
|
|
t.setLine(t.line, t.pos)
|
|
default:
|
|
if t.AutoCompleteCallback != nil {
|
|
prefix := string(t.line[:t.pos])
|
|
suffix := string(t.line[t.pos:])
|
|
|
|
t.lock.Unlock()
|
|
newLine, newPos, completeOk := t.AutoCompleteCallback(prefix+suffix, len(prefix), key)
|
|
t.lock.Lock()
|
|
|
|
if completeOk {
|
|
t.setLine([]rune(newLine), utf8.RuneCount([]byte(newLine)[:newPos]))
|
|
return
|
|
}
|
|
}
|
|
if !isPrintable(key) {
|
|
return
|
|
}
|
|
if len(t.line) == maxLineLength {
|
|
return
|
|
}
|
|
t.addKeyToLine(key)
|
|
}
|
|
return
|
|
}
|
|
|
|
// addKeyToLine inserts the given key at the current position in the current
|
|
// line.
|
|
func (t *Terminal) addKeyToLine(key rune) {
|
|
if len(t.line) == cap(t.line) {
|
|
newLine := make([]rune, 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] = key
|
|
if t.echo {
|
|
t.writeLine(t.line[t.pos:])
|
|
}
|
|
t.pos++
|
|
t.moveCursorToPos(t.pos)
|
|
}
|
|
|
|
func (t *Terminal) writeLine(line []rune) {
|
|
for len(line) != 0 {
|
|
remainingOnLine := t.termWidth - t.cursorX
|
|
todo := len(line)
|
|
if todo > remainingOnLine {
|
|
todo = remainingOnLine
|
|
}
|
|
t.queue(line[:todo])
|
|
t.advanceCursor(visualLength(line[:todo]))
|
|
line = line[todo:]
|
|
}
|
|
}
|
|
|
|
// writeWithCRLF writes buf to w but replaces all occurrences of \n with \r\n.
|
|
func writeWithCRLF(w io.Writer, buf []byte) (n int, err error) {
|
|
for len(buf) > 0 {
|
|
i := bytes.IndexByte(buf, '\n')
|
|
todo := len(buf)
|
|
if i >= 0 {
|
|
todo = i
|
|
}
|
|
|
|
var nn int
|
|
nn, err = w.Write(buf[:todo])
|
|
n += nn
|
|
if err != nil {
|
|
return n, err
|
|
}
|
|
buf = buf[todo:]
|
|
|
|
if i >= 0 {
|
|
if _, err = w.Write(crlf); err != nil {
|
|
return n, err
|
|
}
|
|
n++
|
|
buf = buf[1:]
|
|
}
|
|
}
|
|
|
|
return n, nil
|
|
}
|
|
|
|
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 writeWithCRLF(t.c, 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 = writeWithCRLF(t.c, buf); err != nil {
|
|
return
|
|
}
|
|
|
|
t.writeLine(t.prompt)
|
|
if t.echo {
|
|
t.writeLine(t.line)
|
|
}
|
|
|
|
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 = []rune(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(t.prompt)
|
|
t.c.Write(t.outBuf)
|
|
t.outBuf = t.outBuf[:0]
|
|
}
|
|
|
|
lineIsPasted := t.pasteActive
|
|
|
|
for {
|
|
rest := t.remainder
|
|
lineOk := false
|
|
for !lineOk {
|
|
var key rune
|
|
key, rest = bytesToKey(rest, t.pasteActive)
|
|
if key == utf8.RuneError {
|
|
break
|
|
}
|
|
if !t.pasteActive {
|
|
if key == keyCtrlD {
|
|
if len(t.line) == 0 {
|
|
return "", io.EOF
|
|
}
|
|
}
|
|
if key == keyPasteStart {
|
|
t.pasteActive = true
|
|
if len(t.line) == 0 {
|
|
lineIsPasted = true
|
|
}
|
|
continue
|
|
}
|
|
} else if key == keyPasteEnd {
|
|
t.pasteActive = false
|
|
continue
|
|
}
|
|
if !t.pasteActive {
|
|
lineIsPasted = false
|
|
}
|
|
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 {
|
|
if t.echo {
|
|
t.historyIndex = -1
|
|
t.history.Add(line)
|
|
}
|
|
if lineIsPasted {
|
|
err = ErrPasteIndicator
|
|
}
|
|
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)]
|
|
}
|
|
}
|
|
|
|
// 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 = []rune(prompt)
|
|
}
|
|
|
|
func (t *Terminal) clearAndRepaintLinePlusNPrevious(numPrevLines int) {
|
|
// Move cursor to column zero at the start of the line.
|
|
t.move(t.cursorY, 0, t.cursorX, 0)
|
|
t.cursorX, t.cursorY = 0, 0
|
|
t.clearLineToRight()
|
|
for t.cursorY < numPrevLines {
|
|
// Move down a line
|
|
t.move(0, 1, 0, 0)
|
|
t.cursorY++
|
|
t.clearLineToRight()
|
|
}
|
|
// Move back to beginning.
|
|
t.move(t.cursorY, 0, 0, 0)
|
|
t.cursorX, t.cursorY = 0, 0
|
|
|
|
t.queue(t.prompt)
|
|
t.advanceCursor(visualLength(t.prompt))
|
|
t.writeLine(t.line)
|
|
t.moveCursorToPos(t.pos)
|
|
}
|
|
|
|
func (t *Terminal) SetSize(width, height int) error {
|
|
t.lock.Lock()
|
|
defer t.lock.Unlock()
|
|
|
|
if width == 0 {
|
|
width = 1
|
|
}
|
|
|
|
oldWidth := t.termWidth
|
|
t.termWidth, t.termHeight = width, height
|
|
|
|
switch {
|
|
case width == oldWidth:
|
|
// If the width didn't change then nothing else needs to be
|
|
// done.
|
|
return nil
|
|
case len(t.line) == 0 && t.cursorX == 0 && t.cursorY == 0:
|
|
// If there is nothing on current line and no prompt printed,
|
|
// just do nothing
|
|
return nil
|
|
case width < oldWidth:
|
|
// Some terminals (e.g. xterm) will truncate lines that were
|
|
// too long when shinking. Others, (e.g. gnome-terminal) will
|
|
// attempt to wrap them. For the former, repainting t.maxLine
|
|
// works great, but that behaviour goes badly wrong in the case
|
|
// of the latter because they have doubled every full line.
|
|
|
|
// We assume that we are working on a terminal that wraps lines
|
|
// and adjust the cursor position based on every previous line
|
|
// wrapping and turning into two. This causes the prompt on
|
|
// xterms to move upwards, which isn't great, but it avoids a
|
|
// huge mess with gnome-terminal.
|
|
if t.cursorX >= t.termWidth {
|
|
t.cursorX = t.termWidth - 1
|
|
}
|
|
t.cursorY *= 2
|
|
t.clearAndRepaintLinePlusNPrevious(t.maxLine * 2)
|
|
case width > oldWidth:
|
|
// If the terminal expands then our position calculations will
|
|
// be wrong in the future because we think the cursor is
|
|
// |t.pos| chars into the string, but there will be a gap at
|
|
// the end of any wrapped line.
|
|
//
|
|
// But the position will actually be correct until we move, so
|
|
// we can move back to the beginning and repaint everything.
|
|
t.clearAndRepaintLinePlusNPrevious(t.maxLine)
|
|
}
|
|
|
|
_, err := t.c.Write(t.outBuf)
|
|
t.outBuf = t.outBuf[:0]
|
|
return err
|
|
}
|
|
|
|
type pasteIndicatorError struct{}
|
|
|
|
func (pasteIndicatorError) Error() string {
|
|
return "terminal: ErrPasteIndicator not correctly handled"
|
|
}
|
|
|
|
// ErrPasteIndicator may be returned from ReadLine as the error, in addition
|
|
// to valid line data. It indicates that bracketed paste mode is enabled and
|
|
// that the returned line consists only of pasted data. Programs may wish to
|
|
// interpret pasted data more literally than typed data.
|
|
var ErrPasteIndicator = pasteIndicatorError{}
|
|
|
|
// SetBracketedPasteMode requests that the terminal bracket paste operations
|
|
// with markers. Not all terminals support this but, if it is supported, then
|
|
// enabling this mode will stop any autocomplete callback from running due to
|
|
// pastes. Additionally, any lines that are completely pasted will be returned
|
|
// from ReadLine with the error set to ErrPasteIndicator.
|
|
func (t *Terminal) SetBracketedPasteMode(on bool) {
|
|
if on {
|
|
io.WriteString(t.c, "\x1b[?2004h")
|
|
} else {
|
|
io.WriteString(t.c, "\x1b[?2004l")
|
|
}
|
|
}
|
|
|
|
// stRingBuffer is a ring buffer of strings.
|
|
type stRingBuffer struct {
|
|
// entries contains max elements.
|
|
entries []string
|
|
max int
|
|
// head contains the index of the element most recently added to the ring.
|
|
head int
|
|
// size contains the number of elements in the ring.
|
|
size int
|
|
}
|
|
|
|
func (s *stRingBuffer) Add(a string) {
|
|
if s.entries == nil {
|
|
const defaultNumEntries = 100
|
|
s.entries = make([]string, defaultNumEntries)
|
|
s.max = defaultNumEntries
|
|
}
|
|
|
|
s.head = (s.head + 1) % s.max
|
|
s.entries[s.head] = a
|
|
if s.size < s.max {
|
|
s.size++
|
|
}
|
|
}
|
|
|
|
// NthPreviousEntry returns the value passed to the nth previous call to Add.
|
|
// If n is zero then the immediately prior value is returned, if one, then the
|
|
// next most recent, and so on. If such an element doesn't exist then ok is
|
|
// false.
|
|
func (s *stRingBuffer) NthPreviousEntry(n int) (value string, ok bool) {
|
|
if n >= s.size {
|
|
return "", false
|
|
}
|
|
index := s.head - n
|
|
if index < 0 {
|
|
index += s.max
|
|
}
|
|
return s.entries[index], true
|
|
}
|
|
|
|
// readPasswordLine reads from reader until it finds \n or io.EOF.
|
|
// The slice returned does not include the \n.
|
|
// readPasswordLine also ignores any \r it finds.
|
|
func readPasswordLine(reader io.Reader) ([]byte, error) {
|
|
var buf [1]byte
|
|
var ret []byte
|
|
|
|
for {
|
|
n, err := reader.Read(buf[:])
|
|
if n > 0 {
|
|
switch buf[0] {
|
|
case '\n':
|
|
return ret, nil
|
|
case '\r':
|
|
// remove \r from passwords on Windows
|
|
default:
|
|
ret = append(ret, buf[0])
|
|
}
|
|
continue
|
|
}
|
|
if err != nil {
|
|
if err == io.EOF && len(ret) > 0 {
|
|
return ret, nil
|
|
}
|
|
return ret, err
|
|
}
|
|
}
|
|
}
|