TrinetraLabs/Placebo_AI

1// Copyright Joyent, Inc. and other Node contributors.2//3// Permission is hereby granted, free of charge, to any person obtaining a4// copy of this software and associated documentation files (the5// "Software"), to deal in the Software without restriction, including6// without limitation the rights to use, copy, modify, merge, publish,7// distribute, sublicense, and/or sell copies of the Software, and to permit8// persons to whom the Software is furnished to do so, subject to the9// following conditions:10//11// The above copyright notice and this permission notice shall be included12// in all copies or substantial portions of the Software.13//14// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS15// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF16// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN17// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,18// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR19// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE20// USE OR OTHER DEALINGS IN THE SOFTWARE.21 22// a duplex stream is just a stream that is both readable and writable.23// Since JS doesn't have multiple prototypal inheritance, this class24// prototypally inherits from Readable, and then parasitically from25// Writable.26 27'use strict';28 29/*<replacement>*/30 31var pna = require('process-nextick-args');32/*</replacement>*/33 34/*<replacement>*/35var objectKeys = Object.keys || function (obj) {36  var keys = [];37  for (var key in obj) {38    keys.push(key);39  }return keys;40};41/*</replacement>*/42 43module.exports = Duplex;44 45/*<replacement>*/46var util = Object.create(require('core-util-is'));47util.inherits = require('inherits');48/*</replacement>*/49 50var Readable = require('./_stream_readable');51var Writable = require('./_stream_writable');52 53util.inherits(Duplex, Readable);54 55{56  // avoid scope creep, the keys array can then be collected57  var keys = objectKeys(Writable.prototype);58  for (var v = 0; v < keys.length; v++) {59    var method = keys[v];60    if (!Duplex.prototype[method]) Duplex.prototype[method] = Writable.prototype[method];61  }62}63 64function Duplex(options) {65  if (!(this instanceof Duplex)) return new Duplex(options);66 67  Readable.call(this, options);68  Writable.call(this, options);69 70  if (options && options.readable === false) this.readable = false;71 72  if (options && options.writable === false) this.writable = false;73 74  this.allowHalfOpen = true;75  if (options && options.allowHalfOpen === false) this.allowHalfOpen = false;76 77  this.once('end', onend);78}79 80Object.defineProperty(Duplex.prototype, 'writableHighWaterMark', {81  // making it explicit this property is not enumerable82  // because otherwise some prototype manipulation in83  // userland will fail84  enumerable: false,85  get: function () {86    return this._writableState.highWaterMark;87  }88});89 90// the no-half-open enforcer91function onend() {92  // if we allow half-open state, or if the writable side ended,93  // then we're ok.94  if (this.allowHalfOpen || this._writableState.ended) return;95 96  // no more data can be written.97  // But allow more writes to happen in this tick.98  pna.nextTick(onEndNT, this);99}100 101function onEndNT(self) {102  self.end();103}104 105Object.defineProperty(Duplex.prototype, 'destroyed', {106  get: function () {107    if (this._readableState === undefined || this._writableState === undefined) {108      return false;109    }110    return this._readableState.destroyed && this._writableState.destroyed;111  },112  set: function (value) {113    // we ignore the value if the stream114    // has not been initialized yet115    if (this._readableState === undefined || this._writableState === undefined) {116      return;117    }118 119    // backward compatibility, the user is explicitly120    // managing destroyed121    this._readableState.destroyed = value;122    this._writableState.destroyed = value;123  }124});125 126Duplex.prototype._destroy = function (err, cb) {127  this.push(null);128  this.end();129 130  pna.nextTick(cb, err);131};