1  'use strict'
 2  
 3  const DuplexStream = require('readable-stream').Duplex
 4  const inherits = require('inherits')
 5  const BufferList = require('./BufferList')
 6  
 7  function BufferListStream (callback) {
 8    if (!(this instanceof BufferListStream)) {
 9      return new BufferListStream(callback)
10    }
11  
12    if (typeof callback === 'function') {
13      this._callback = callback
14  
15      const piper = function piper (err) {
16        if (this._callback) {
17          this._callback(err)
18          this._callback = null
19        }
20      }.bind(this)
21  
22      this.on('pipe', function onPipe (src) {
23        src.on('error', piper)
24      })
25      this.on('unpipe', function onUnpipe (src) {
26        src.removeListener('error', piper)
27      })
28  
29      callback = null
30    }
31  
32    BufferList._init.call(this, callback)
33    DuplexStream.call(this)
34  }
35  
36  inherits(BufferListStream, DuplexStream)
37  Object.assign(BufferListStream.prototype, BufferList.prototype)
38  
39  BufferListStream.prototype._new = function _new (callback) {
40    return new BufferListStream(callback)
41  }
42  
43  BufferListStream.prototype._write = function _write (buf, encoding, callback) {
44    this._appendBuffer(buf)
45  
46    if (typeof callback === 'function') {
47      callback()
48    }
49  }
50  
51  BufferListStream.prototype._read = function _read (size) {
52    if (!this.length) {
53      return this.push(null)
54    }
55  
56    size = Math.min(size, this.length)
57    this.push(this.slice(0, size))
58    this.consume(size)
59  }
60  
61  BufferListStream.prototype.end = function end (chunk) {
62    DuplexStream.prototype.end.call(this, chunk)
63  
64    if (this._callback) {
65      this._callback(null, this.slice())
66      this._callback = null
67    }
68  }
69  
70  BufferListStream.prototype._destroy = function _destroy (err, cb) {
71    this._bufs.length = 0
72    this.length = 0
73    cb(err)
74  }
75  
76  BufferListStream.prototype._isBufferList = function _isBufferList (b) {
77    return b instanceof BufferListStream || b instanceof BufferList || BufferListStream.isBufferList(b)
78  }
79  
80  BufferListStream.isBufferList = BufferList.isBufferList
81  
82  module.exports = BufferListStream
83  module.exports.BufferListStream = BufferListStream
84  module.exports.BufferList = BufferList