// 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. // a duplex stream is just a stream that is both readable and writable. // Since JS doesn't have multiple prototypal inheritance, this class // prototypally inherits from Readable, and then parasitically from // Writable. 'use strict'; /*<replacement>*/ var pna = require('process-nextick-args'); /*</replacement>*/ /*<replacement>*/ var objectKeys = Object.keys || function (obj) { var keys = []; for (var key in obj) { keys.push(key); }return keys; }; /*</replacement>*/ module.exports = Duplex; /*<replacement>*/ var util = require('core-util-is'); util.inherits = require('inherits'); /*</replacement>*/ var Readable = require('./_stream_readable'); var Writable = require('./_stream_writable'); util.inherits(Duplex, Readable); { // avoid scope creep, the keys array can then be collected var keys = objectKeys(Writable.prototype); for (var v = 0; v < keys.length; v++) { var method = keys[v]; if (!Duplex.prototype[method]) Duplex.prototype[method] = Writable.prototype[method]; } } function Duplex(options) { if (!(this instanceof Duplex)) return new Duplex(options); Readable.call(this, options); Writable.call(this, options); if (options && options.readable === false) this.readable = false; if (options && options.writable === false) this.writable = false; this.allowHalfOpen = true; if (options && options.allowHalfOpen === false) this.allowHalfOpen = false; this.once('end', onend); } Object.defineProperty(Duplex.prototype, 'writableHighWaterMark', { // making it explicit this property is not enumerable // because otherwise some prototype manipulation in // userland will fail enumerable: false, get: function () { return this._writableState.highWaterMark; } }); // the no-half-open enforcer function onend() { // if we allow half-open state, or if the writable side ended, // then we're ok. if (this.allowHalfOpen || this._writableState.ended) return; // no more data can be written. // But allow more writes to happen in this tick. pna.nextTick(onEndNT, this); } function onEndNT(self) { self.end(); } Object.defineProperty(Duplex.prototype, 'destroyed', { get: function () { if (this._readableState === undefined || this._writableState === undefined) { return false; } return this._readableState.destroyed && this._writableState.destroyed; }, set: function (value) { // we ignore the value if the stream // has not been initialized yet if (this._readableState === undefined || this._writableState === undefined) { return; } // backward compatibility, the user is explicitly // managing destroyed this._readableState.destroyed = value; this._writableState.destroyed = value; } }); Duplex.prototype._destroy = function (err, cb) { this.push(null); this.end(); pna.nextTick(cb, err); };