graceful-fs.js

var fs = require('fs')
var polyfills = require('./polyfills.js')
var legacy = require('./legacy-streams.js')
var clone = require('./clone.js')

var util = require('util')

/* istanbul ignore next - node 0.x polyfill */
var gracefulQueue
var previousSymbol

/* istanbul ignore else - node 0.x polyfill */
if (typeof Symbol === 'function' && typeof Symbol.for === 'function') {
  gracefulQueue = Symbol.for('graceful-fs.queue')
  // This is used in testing by future versions
  previousSymbol = Symbol.for('graceful-fs.previous')
} else {
  gracefulQueue = '___graceful-fs.queue'
  previousSymbol = '___graceful-fs.previous'
}

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)
  }

// Once time initialization
if (!global[gracefulQueue]) {
  // This queue can be shared by multiple loaded instances
  var queue = []
  Object.defineProperty(global, gracefulQueue, {
    get: function() {
      return queue
    }
  })

  // Patch fs.close/closeSync to shared queue version, because we need
  // 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.
  fs.close = (function (fs$close) {
    function close (fd, cb) {
      return fs$close.call(fs, fd, function (err) {
        // This function uses the graceful-fs shared queue
        if (!err) {
          retry()
        }

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

    Object.defineProperty(close, previousSymbol, {
      value: fs$close
    })
    return close
  })(fs.close)

  fs.closeSync = (function (fs$closeSync) {
    function closeSync (fd) {
      // This function uses the graceful-fs shared queue
      fs$closeSync.apply(fs, arguments)