lts/lib/tty.js
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.
'use strict';
const {
Array,
NumberIsInteger,
ObjectSetPrototypeOf,
} = primordials;
const net = require('net');
const { TTY, isTTY } = internalBinding('tty_wrap');
const errors = require('internal/errors');
const { ERR_INVALID_FD, ERR_TTY_INIT_FAILED } = errors.codes;
const {
getColorDepth,
hasColors
} = require('internal/tty');
// Lazy loaded for startup performance.
let readline;
function isatty(fd) {
return NumberIsInteger(fd) && fd >= 0 && isTTY(fd);
}
function ReadStream(fd, options) {
if (!(this instanceof ReadStream))
return new ReadStream(fd, options);
if (fd >> 0 !== fd || fd < 0)
throw new ERR_INVALID_FD(fd);
const ctx = {};
const tty = new TTY(fd, true, ctx);
if (ctx.code !== undefined) {
throw new ERR_TTY_INIT_FAILED(ctx);
}
net.Socket.call(this, {
highWaterMark: 0,
readable: true,
writable: false,
handle: tty,
...options
});
this.isRaw = false;
this.isTTY = true;
}
ObjectSetPrototypeOf(ReadStream.prototype, net.Socket.prototype);
ObjectSetPrototypeOf(ReadStream, net.Socket);
ReadStream.prototype.setRawMode = function(flag) {
flag = !!flag;
const err = this._handle.setRawMode(flag);
if (err) {
this.emit('error', errors.errnoException(err, 'setRawMode'));
return this;
}
this.isRaw = flag;
return this;
};
function WriteStream(fd) {
if (!(this instanceof WriteStream))
return new WriteStream(fd);
if (fd >> 0 !== fd || fd < 0)
throw new ERR_INVALID_FD(fd);
const ctx = {};
const tty = new TTY(fd, false, ctx);
if (ctx.code !== undefined) {
throw new ERR_TTY_INIT_FAILED(ctx);
}
net.Socket.call(this, {
handle: tty,
readable: false,
writable: true
});
// Prevents interleaved or dropped stdout/stderr output for terminals.
// As noted in the following reference, local TTYs tend to be quite fast and
// this behavior has become expected due historical functionality on OS X,
// even though it was originally intended to change in v1.0.2 (Libuv 1.2.1).
// Ref: https://github.com/nodejs/node/pull/1771#issuecomment-119351671
this._handle.setBlocking(true);
const winSize = new Array(2);
const err = this._handle.getWindowSize(winSize);
if (!err) {
this.columns = winSize[0];
this.rows = winSize[1];
}
}
ObjectSetPrototypeOf(WriteStream.prototype, net.Socket.prototype);
ObjectSetPrototypeOf(WriteStream, net.Socket);
WriteStream.prototype.isTTY = true;
WriteStream.prototype.getColorDepth = getColorDepth;
WriteStream.prototype.hasColors = hasColors;
WriteStream.prototype._refreshSize = function() {
const oldCols = this.columns;
const oldRows = this.rows;
const winSize = new Array(2);
const err = this._handle.getWindowSize(winSize);
if (err) {
this.emit('error', errors.errnoException(err, 'getWindowSize'));
return;
}
const [newCols, newRows] = winSize;
if (oldCols !== newCols || oldRows !== newRows) {
this.columns = newCols;
this.rows = newRows;
this.emit('resize');
}
};
// Backwards-compat
WriteStream.prototype.cursorTo = function(x, y, callback) {
if (readline === undefined) readline = require('readline');
return readline.cursorTo(this, x, y, callback);
};
WriteStream.prototype.moveCursor = function(dx, dy, callback) {
if (readline === undefined) readline = require('readline');
return readline.moveCursor(this, dx, dy, callback);
};
WriteStream.prototype.clearLine = function(dir, callback) {
if (readline === undefined) readline = require('readline');
return readline.clearLine(this, dir, callback);
};
WriteStream.prototype.clearScreenDown = function(callback) {
if (readline === undefined) readline = require('readline');
return readline.clearScreenDown(this, callback);
};
WriteStream.prototype.getWindowSize = function() {
return [this.columns, this.rows];
};
module.exports = { isatty, ReadStream, WriteStream };