| 'use strict'; | 
|   | 
| /*<replacement>*/ | 
|   | 
| var pna = require('process-nextick-args'); | 
| /*</replacement>*/ | 
|   | 
| // undocumented cb() API, needed for core, not for public API | 
| function destroy(err, cb) { | 
|   var _this = this; | 
|   | 
|   var readableDestroyed = this._readableState && this._readableState.destroyed; | 
|   var writableDestroyed = this._writableState && this._writableState.destroyed; | 
|   | 
|   if (readableDestroyed || writableDestroyed) { | 
|     if (cb) { | 
|       cb(err); | 
|     } else if (err && (!this._writableState || !this._writableState.errorEmitted)) { | 
|       pna.nextTick(emitErrorNT, this, err); | 
|     } | 
|     return this; | 
|   } | 
|   | 
|   // we set destroyed to true before firing error callbacks in order | 
|   // to make it re-entrance safe in case destroy() is called within callbacks | 
|   | 
|   if (this._readableState) { | 
|     this._readableState.destroyed = true; | 
|   } | 
|   | 
|   // if this is a duplex stream mark the writable part as destroyed as well | 
|   if (this._writableState) { | 
|     this._writableState.destroyed = true; | 
|   } | 
|   | 
|   this._destroy(err || null, function (err) { | 
|     if (!cb && err) { | 
|       pna.nextTick(emitErrorNT, _this, err); | 
|       if (_this._writableState) { | 
|         _this._writableState.errorEmitted = true; | 
|       } | 
|     } else if (cb) { | 
|       cb(err); | 
|     } | 
|   }); | 
|   | 
|   return this; | 
| } | 
|   | 
| function undestroy() { | 
|   if (this._readableState) { | 
|     this._readableState.destroyed = false; | 
|     this._readableState.reading = false; | 
|     this._readableState.ended = false; | 
|     this._readableState.endEmitted = false; | 
|   } | 
|   | 
|   if (this._writableState) { | 
|     this._writableState.destroyed = false; | 
|     this._writableState.ended = false; | 
|     this._writableState.ending = false; | 
|     this._writableState.finished = false; | 
|     this._writableState.errorEmitted = false; | 
|   } | 
| } | 
|   | 
| function emitErrorNT(self, err) { | 
|   self.emit('error', err); | 
| } | 
|   | 
| module.exports = { | 
|   destroy: destroy, | 
|   undestroy: undestroy | 
| }; |