aboutsummaryrefslogtreecommitdiff
path: root/node_modules/graceful-fs/graceful-fs.js
blob: ac206757e63c5ace954ca0643c05f5a63b3373f0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
var fs = require('fs')
var polyfills = require('./polyfills.js')
var legacy = require('./legacy-streams.js')
var clone = require('./clone.js')

var queue = []

var util = require('util')

function noop () {}

var debug = noop
if (util.debuglog)
  debug = util.debuglog('gfs4')
else if (/\bgfs4\b/i.test(process.env.NODE_DEBUG || ''))
  debug = function() {
    var m = util.format.apply(util, arguments)
    m = 'GFS4: ' + m.split(/\n/).join('\nGFS4: ')
    console.error(m)
  }

if (/\bgfs4\b/i.test(process.env.NODE_DEBUG || '')) {
  process.on('exit', function() {
    debug(queue)
    require('assert').equal(queue.length, 0)
  })
}

module.exports = patch(clone(fs))
if (process.env.TEST_GRACEFUL_FS_GLOBAL_PATCH && !fs.__patched) {
    module.exports = patch(fs)
    fs.__patched = true;
}

// Always patch fs.close/closeSync, because we want to
// retry() whenever a close happens *anywhere* in the program.
// This is essential when multiple graceful-fs instances are
// in play at the same time.
module.exports.close = (function (fs$close) { return function (fd, cb) {
  return fs$close.call(fs, fd, function (err) {
    if (!err)
      retry()

    if (typeof cb === 'function')
      cb.apply(this, arguments)
  })
}})(fs.close)

module.exports.closeSync = (function (fs$closeSync) { return function (fd) {
  // Note that graceful-fs also retries when fs.closeSync() fails.
  // Looks like a bug to me, although it's probably a harmless one.
  var rval = fs$closeSync.apply(fs, arguments)
  retry()
  return rval
}})(fs.closeSync)

// Only patch fs once, otherwise we'll run into a memory leak if
// graceful-fs is loaded multiple times, such as in test environments that
// reset the loaded modules between tests.
// We look for the string `graceful-fs` from the comment above. This
// way we are not adding any extra properties and it will detect if older
// versions of graceful-fs are installed.
if (!/\bgraceful-fs\b/.test(fs.closeSync.toString())) {
  fs.closeSync = module.exports.closeSync;
  fs.close = module.exports.close;
}

function patch (fs) {
  // Everything that references the open() function needs to be in here
  polyfills(fs)
  fs.gracefulify = patch
  fs.FileReadStream = ReadStream;  // Legacy name.
  fs.FileWriteStream = WriteStream;  // Legacy name.
  fs.createReadStream = createReadStream
  fs.createWriteStream = createWriteStream
  var fs$readFile = fs.readFile
  fs.readFile = readFile
  function readFile (path, options, cb) {
    if (typeof options === 'function')
      cb = options, options = null

    return go$readFile(path, options, cb)

    function go$readFile (path, options, cb) {
      return fs$readFile(path, options, function (err) {
        if (err && (err.code === 'EMFILE' || err.code === 'ENFILE'))
          enqueue([go$readFile, [path, options, cb]])
        else {
          if (typeof cb === 'function')
            cb.apply(this, arguments)
          retry()
        }
      })
    }
  }

  var fs$writeFile = fs.writeFile
  fs.writeFile = writeFile
  function writeFile (path, data, options, cb) {
    if (typeof options === 'function')
      cb = options, options = null

    return go$writeFile(path, data, options, cb)

    function go$writeFile (path, data, options, cb) {
      return fs$writeFile(path, data, options, function (err) {
        if (err && (err.code === 'EMFILE' || err.code === 'ENFILE'))
          enqueue([go$writeFile, [path, data, options, cb]])
        else {
          if (typeof cb === 'function')
            cb.apply(this, arguments)
          retry()
        }
      })
    }
  }

  var fs$appendFile = fs.appendFile
  if (fs$appendFile)
    fs.appendFile = appendFile
  function appendFile (path, data, options, cb) {
    if (typeof options === 'function')
      cb = options, options = null

    return go$appendFile(path, data, options, cb)

    function go$appendFile (path, data, options, cb) {
      return fs$appendFile(path, data, options, function (err) {
        if (err && (err.code === 'EMFILE' || err.code === 'ENFILE'))
          enqueue([go$appendFile, [path, data, options, cb]])
        else {
          if (typeof cb === 'function')
            cb.apply(this, arguments)
          retry()
        }
      })
    }
  }

  var fs$readdir = fs.readdir
  fs.readdir = readdir
  function readdir (path, options, cb) {
    var args = [path]
    if (typeof options !== 'function') {
      args.push(options)
    } else {
      cb = options
    }
    args.push(go$readdir$cb)

    return go$readdir(args)

    function go$readdir$cb (err, files) {
      if (files && files.sort)
        files.sort()

      if (err && (err.code === 'EMFILE' || err.code === 'ENFILE'))
        enqueue([go$readdir, [args]])

      else {
        if (typeof cb === 'function')
          cb.apply(this, arguments)
        retry()
      }
    }
  }

  function go$readdir (args) {
    return fs$readdir.apply(fs, args)
  }

  if (process.version.substr(0, 4) === 'v0.8') {
    var legStreams = legacy(fs)
    ReadStream = legStreams.ReadStream
    WriteStream = legStreams.WriteStream
  }

  var fs$ReadStream = fs.ReadStream
  if (fs$ReadStream) {
    ReadStream.prototype = Object.create(fs$ReadStream.prototype)
    ReadStream.prototype.open = ReadStream$open
  }

  var fs$WriteStream = fs.WriteStream
  if (fs$WriteStream) {
    WriteStream.prototype = Object.create(fs$WriteStream.prototype)
    WriteStream.prototype.open = WriteStream$open
  }

  fs.ReadStream = ReadStream
  fs.WriteStream = WriteStream

  function ReadStream (path, options) {
    if (this instanceof ReadStream)
      return fs$ReadStream.apply(this, arguments), this
    else
      return ReadStream.apply(Object.create(ReadStream.prototype), arguments)
  }

  function ReadStream$open () {
    var that = this
    open(that.path, that.flags, that.mode, function (err, fd) {
      if (err) {
        if (that.autoClose)
          that.destroy()

        that.emit('error', err)
      } else {
        that.fd = fd
        that.emit('open', fd)
        that.read()
      }
    })
  }

  function WriteStream (path, options) {
    if (this instanceof WriteStream)
      return fs$WriteStream.apply(this, arguments), this
    else
      return WriteStream.apply(Object.create(WriteStream.prototype), arguments)
  }

  function WriteStream$open () {
    var that = this
    open(that.path, that.flags, that.mode, function (err, fd) {
      if (err) {
        that.destroy()
        that.emit('error', err)
      } else {
        that.fd = fd
        that.emit('open', fd)
      }
    })
  }

  function createReadStream (path, options) {
    return new ReadStream(path, options)
  }

  function createWriteStream (path, options) {
    return new WriteStream(path, options)
  }

  var fs$open = fs.open
  fs.open = open
  function open (path, flags, mode, cb) {
    if (typeof mode === 'function')
      cb = mode, mode = null

    return go$open(path, flags, mode, cb)

    function go$open (path, flags, mode, cb) {
      return fs$open(path, flags, mode, function (err, fd) {
        if (err && (err.code === 'EMFILE' || err.code === 'ENFILE'))
          enqueue([go$open, [path, flags, mode, cb]])
        else {
          if (typeof cb === 'function')
            cb.apply(this, arguments)
          retry()
        }
      })
    }
  }

  return fs
}

function enqueue (elem) {
  debug('ENQUEUE', elem[0].name, elem[1])
  queue.push(elem)
}

function retry () {
  var elem = queue.shift()
  if (elem) {
    debug('RETRY', elem[0].name, elem[1])
    elem[0].apply(null, elem[1])
  }
}