node/lib/readline.js

289 строки
6.8 KiB
JavaScript

// Inspiration for this code comes from Salvatore Sanfilippo's linenoise.
// http://github.com/antirez/linenoise
// Reference:
// * http://invisible-island.net/xterm/ctlseqs/ctlseqs.html
// * http://www.3waylabs.com/nw/WWW/products/wizcon/vt220.html
var kHistorySize = 30;
var kBufSize = 10*1024;
var Buffer = require('buffer').Buffer;
var inherits = require('sys').inherits;
var EventEmitter = require('events').EventEmitter;
var stdio = process.binding('stdio');
exports.createInterface = function (output, isTTY) {
return new Interface(output, isTTY);
};
function Interface (output, isTTY) {
this.output = output;
this.setPrompt("node> ");
// Current line
this.buf = new Buffer(kBufSize);
this.buf.used = 0;
if (!isTTY) {
this._tty = false;
} else {
// input refers to stdin
// Check process.env.TERM ?
stdio.setRawMode(true);
this._tty = true;
this.columns = stdio.getColumns();
// Cursor position on the line.
this.cursor = 0;
this.history = [];
this.historyIndex = -1;
}
}
inherits(Interface, EventEmitter);
Interface.prototype.setPrompt = function (prompt, length) {
this._prompt = prompt;
this._promptLength = length ? length : Buffer.byteLength(prompt);
};
Interface.prototype.prompt = function () {
if (this._tty) {
this.buf.used = 0;
this.cursor = 0;
this._refreshLine();
} else {
this.output.write(this._prompt);
}
};
Interface.prototype._addHistory = function () {
if (this.buf.used === 0) return "";
var b = new Buffer(this.buf.used);
this.buf.copy(b, 0, 0, this.buf.used);
this.buf.used = 0;
this.history.unshift(b);
this.historyIndex = -1;
this.cursor = 0;
// Only store so many
if (this.history.length > kHistorySize) this.history.pop();
return b.toString('utf8');
};
Interface.prototype._refreshLine = function () {
if (this._closed) return;
stdio.setRawMode(true);
// Cursor to left edge.
this.output.write('\x1b[0G');
// Write the prompt and the current buffer content.
this.output.write(this._prompt);
if (this.buf.used > 0) {
this.output.write(this.buf.slice(0, this.buf.used));
}
// Erase to right.
this.output.write('\x1b[0K');
// Move cursor to original position.
this.output.write('\x1b[0G\x1b[' + (this._promptLength + this.cursor) + 'C');
};
Interface.prototype.close = function (d) {
if (this._tty) {
stdio.setRawMode(false);
}
this.emit('close');
this._closed = true;
};
Interface.prototype.write = function (d) {
if (this._closed) return;
return this._tty ? this._ttyWrite(d) : this._normalWrite(d);
};
Interface.prototype._normalWrite = function (b) {
for (var i = 0; i < b.length; i++) {
var code = b instanceof Buffer ? b[i] : b.charCodeAt(i);
if (code === '\n'.charCodeAt(0) || code === '\r'.charCodeAt(0)) {
var s = this.buf.toString('utf8', 0, this.buf.used);
this.emit('line', s);
this.buf.used = 0;
} else {
this.buf[this.buf.used++] = code;
}
}
};
Interface.prototype._historyNext = function () {
if (this.historyIndex > 0) {
this.historyIndex--;
this.history[this.historyIndex].copy(this.buf, 0);
this.buf.used = this.history[this.historyIndex].length;
// set cursor to end of line.
this.cursor = this.buf.used;
this._refreshLine();
} else if (this.historyIndex === 0) {
this.historyIndex = -1;
this.cursor = 0;
this.buf.used = 0;
this._refreshLine();
}
};
Interface.prototype._historyPrev = function () {
if (this.historyIndex + 1 < this.history.length) {
this.historyIndex++;
this.history[this.historyIndex].copy(this.buf, 0);
this.buf.used = this.history[this.historyIndex].length;
// set cursor to end of line.
this.cursor = this.buf.used;
this._refreshLine();
}
};
// handle a write from the tty
Interface.prototype._ttyWrite = function (b) {
switch (b[0]) {
/* ctrl+c */
case 3:
//process.kill(process.pid, "SIGINT");
this.close();
break;
case 4: // control-d, delete right or EOF
if (this.cursor === 0 && this.buf.used === 0) {
this.close();
} else if (this.cursor < this.buf.used) {
for (var i = this.cursor; i < this.buf.used; i++) {
this.buf[i] = this.buf[i+1];
}
this.buf.used--;
this._refreshLine();
}
break;
case 13: /* enter */
var line = this._addHistory();
this.output.write('\n\x1b[0G');
stdio.setRawMode(false);
this.emit('line', line);
break;
case 127: /* backspace */
case 8: /* ctrl+h */
if (this.cursor > 0 && this.buf.used > 0) {
for (var i = this.cursor; i < this.buf.used; i++) {
this.buf[i-1] = this.buf[i];
}
this.cursor--;
this.buf.used--;
this._refreshLine();
}
break;
case 21: /* Ctrl+u, delete the whole line. */
this.cursor = this.buf.used = 0;
this._refreshLine();
break;
case 11: /* Ctrl+k, delete from current to end of line. */
this.buf.used = this.cursor;
this._refreshLine();
break;
case 1: /* Ctrl+a, go to the start of the line */
this.cursor = 0;
this._refreshLine();
break;
case 5: /* ctrl+e, go to the end of the line */
this.cursor = this.buf.used;
this._refreshLine();
break;
case 2: // control-b, back one character
if (this.cursor > 0) {
this.cursor--;
this._refreshLine();
}
break;
case 6: // control-f, forward one character
if (this.cursor != this.buf.used) {
this.cursor++;
this._refreshLine();
}
break;
case 14: // control-n, next history item
this._historyNext();
break;
case 16: // control-p, previous history item
this._historyPrev();
break;
case 27: /* escape sequence */
if (b[1] === 98 && this.cursor > 0) { // meta-b - backward word
} else if (b[1] === 102 && this.cursor < this.buf.used) { // meta-f - forward word
} else if (b[1] === 91 && b[2] === 68) { // left arrow
if (this.cursor > 0) {
this.cursor--;
this._refreshLine();
}
} else if (b[1] === 91 && b[2] === 67) { // right arrow
if (this.cursor != this.buf.used) {
this.cursor++;
this._refreshLine();
}
} else if (b[1] === 91 && b[2] === 65) { // up arrow
this._historyPrev();
} else if (b[1] === 91 && b[2] === 66) { // down arrow
this._historyNext();
}
break;
default:
if (this.buf.used < kBufSize) {
for (var i = this.buf.used + 1; this.cursor < i; i--) {
this.buf[i] = this.buf[i-1];
}
this.buf[this.cursor++] = b[0];
this.buf.used++;
if (this.buf.used == this.cursor) {
this.output.write(b);
} else {
this._refreshLine();
}
}
break;
}
};