documentit/node_modules/graceful-fs/graceful-fs.js
2018-01-05 10:48:13 -08:00

263 lines
6.8 KiB
JavaScript

var fs = require('fs')
var polyfills = require('./polyfills.js')
var legacy = require('./legacy-streams.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(require('./fs.js'))
if (process.env.TEST_GRACEFUL_FS_GLOBAL_PATCH) {
module.exports = patch(fs)
}
// 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 =
fs.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 =
fs.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)
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
ReadStream.prototype = Object.create(fs$ReadStream.prototype)
ReadStream.prototype.open = ReadStream$open
var fs$WriteStream = fs.WriteStream
WriteStream.prototype = Object.create(fs$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])
}
}