Current File : //opt/alt/alt-nodejs11/root/lib/node_modules/npm/node_modules/fstream/lib/reader.js
module.exports = Reader
var fs = require('graceful-fs')
var Stream = require('stream').Stream
var inherits = require('inherits')
var path = require('path')
var getType = require('./get-type.js')
var hardLinks = Reader.hardLinks = {}
var Abstract = require('./abstract.js')
// Must do this *before* loading the child classes
inherits(Reader, Abstract)
var LinkReader = require('./link-reader.js')
function Reader (props, currentStat) {
var self = this
if (!(self instanceof Reader)) return new Reader(props, currentStat)
if (typeof props === 'string') {
props = { path: props }
}
// polymorphism.
// call fstream.Reader(dir) to get a DirReader object, etc.
// Note that, unlike in the Writer case, ProxyReader is going
// to be the *normal* state of affairs, since we rarely know
// the type of a file prior to reading it.
var type
var ClassType
if (props.type && typeof props.type === 'function') {
type = props.type
ClassType = type
} else {
type = getType(props)
ClassType = Reader
}
if (currentStat && !type) {
type = getType(currentStat)
props[type] = true
props.type = type
}
switch (type) {
case 'Directory':
ClassType = require('./dir-reader.js')
break
case 'Link':
// XXX hard links are just files.
// However, it would be good to keep track of files' dev+inode
// and nlink values, and create a HardLinkReader that emits
// a linkpath value of the original copy, so that the tar
// writer can preserve them.
// ClassType = HardLinkReader
// break
case 'File':
ClassType = require('./file-reader.js')
break
case 'SymbolicLink':
ClassType = LinkReader
break
case 'Socket':
ClassType = require('./socket-reader.js')
break
case null:
ClassType = require('./proxy-reader.js')
break
}
if (!(self instanceof ClassType)) {
return new ClassType(props)
}
Abstract.call(self)
if (!props.path) {
self.error('Must provide a path', null, true)
}
self.readable = true
self.writable = false
self.type = type
self.props = props
self.depth = props.depth = props.depth || 0
self.parent = props.parent || null
self.root = props.root || (props.parent && props.parent.root) || self
self._path = self.path = path.resolve(props.path)
if (process.platform === 'win32') {
self.path = self._path = self.path.replace(/\?/g, '_')
if (self._path.length >= 260) {
// how DOES one create files on the moon?
// if the path has spaces in it, then UNC will fail.
self._swallowErrors = true
// if (self._path.indexOf(" ") === -1) {
self._path = '\\\\?\\' + self.path.replace(/\//g, '\\')
// }
}
}
self.basename = props.basename = path.basename(self.path)
self.dirname = props.dirname = path.dirname(self.path)
// these have served their purpose, and are now just noisy clutter
props.parent = props.root = null
// console.error("\n\n\n%s setting size to", props.path, props.size)
self.size = props.size
self.filter = typeof props.filter === 'function' ? props.filter : null
if (props.sort === 'alpha') props.sort = alphasort
// start the ball rolling.
// this will stat the thing, and then call self._read()
// to start reading whatever it is.
// console.error("calling stat", props.path, currentStat)
self._stat(currentStat)
}
function alphasort (a, b) {
return a === b ? 0
: a.toLowerCase() > b.toLowerCase() ? 1
: a.toLowerCase() < b.toLowerCase() ? -1
: a > b ? 1
: -1
}
Reader.prototype._stat = function (currentStat) {
var self = this
var props = self.props
var stat = props.follow ? 'stat' : 'lstat'
// console.error("Reader._stat", self._path, currentStat)
if (currentStat) process.nextTick(statCb.bind(null, null, currentStat))
else fs[stat](self._path, statCb)
function statCb (er, props_) {
// console.error("Reader._stat, statCb", self._path, props_, props_.nlink)
if (er) return self.error(er)
Object.keys(props_).forEach(function (k) {
props[k] = props_[k]
})
// if it's not the expected size, then abort here.
if (undefined !== self.size && props.size !== self.size) {
return self.error('incorrect size')
}
self.size = props.size
var type = getType(props)
var handleHardlinks = props.hardlinks !== false
// special little thing for handling hardlinks.
if (handleHardlinks && type !== 'Directory' && props.nlink && props.nlink > 1) {
var k = props.dev + ':' + props.ino
// console.error("Reader has nlink", self._path, k)
if (hardLinks[k] === self._path || !hardLinks[k]) {
hardLinks[k] = self._path
} else {
// switch into hardlink mode.
type = self.type = self.props.type = 'Link'
self.Link = self.props.Link = true
self.linkpath = self.props.linkpath = hardLinks[k]
// console.error("Hardlink detected, switching mode", self._path, self.linkpath)
// Setting __proto__ would arguably be the "correct"
// approach here, but that just seems too wrong.
self._stat = self._read = LinkReader.prototype._read
}
}
if (self.type && self.type !== type) {
self.error('Unexpected type: ' + type)
}
// if the filter doesn't pass, then just skip over this one.
// still have to emit end so that dir-walking can move on.
if (self.filter) {
var who = self._proxy || self
// special handling for ProxyReaders
if (!self.filter.call(who, who, props)) {
if (!self._disowned) {
self.abort()
self.emit('end')
self.emit('close')
}
return
}
}
// last chance to abort or disown before the flow starts!
var events = ['_stat', 'stat', 'ready']
var e = 0
;(function go () {
if (self._aborted) {
self.emit('end')
self.emit('close')
return
}
if (self._paused && self.type !== 'Directory') {
self.once('resume', go)
return
}
var ev = events[e++]
if (!ev) {
return self._read()
}
self.emit(ev, props)
go()
})()
}
}
Reader.prototype.pipe = function (dest) {
var self = this
if (typeof dest.add === 'function') {
// piping to a multi-compatible, and we've got directory entries.
self.on('entry', function (entry) {
var ret = dest.add(entry)
if (ret === false) {
self.pause()
}
})
}
// console.error("R Pipe apply Stream Pipe")
return Stream.prototype.pipe.apply(this, arguments)
}
Reader.prototype.pause = function (who) {
this._paused = true
who = who || this
this.emit('pause', who)
if (this._stream) this._stream.pause(who)
}
Reader.prototype.resume = function (who) {
this._paused = false
who = who || this
this.emit('resume', who)
if (this._stream) this._stream.resume(who)
this._read()
}
Reader.prototype._read = function () {
this.error('Cannot read unknown type: ' + this.type)
}
Mini Shell