var util = require('util') var bl = require('bl') var headers = require('./headers') var Writable = require('readable-stream').Writable var PassThrough = require('readable-stream').PassThrough var noop = function () {} var overflow = function (size) { size &= 511 return size && 512 - size } var emptyStream = function (self, offset) { var s = new Source(self, offset) s.end() return s } var mixinPax = function (header, pax) { if (pax.path) header.name = pax.path if (pax.linkpath) header.linkname = pax.linkpath if (pax.size) header.size = parseInt(pax.size, 10) header.pax = pax return header } var Source = function (self, offset) { this._parent = self this.offset = offset PassThrough.call(this, { autoDestroy: false }) } util.inherits(Source, PassThrough) Source.prototype.destroy = function (err) { this._parent.destroy(err) } var Extract = function (opts) { if (!(this instanceof Extract)) return new Extract(opts) Writable.call(this, opts) opts = opts || {} this._offset = 0 this._buffer = bl() this._missing = 0 this._partial = false this._onparse = noop this._header = null this._stream = null this._overflow = null this._cb = null this._locked = false this._destroyed = false this._pax = null this._paxGlobal = null this._gnuLongPath = null this._gnuLongLinkPath = null var self = this var b = self._buffer var oncontinue = function () { self._continue() } var onunlock = function (err) { self._locked = false if (err) return self.destroy(err) if (!self._stream) oncontinue() } var onstreamend = function () { self._stream = null var drain = overflow(self._header.size) if (drain) self._parse(drain, ondrain) else self._parse(512, onheader) if (!self._locked) oncontinue() } var ondrain = function () { self._buffer.consume(overflow(self._header.size)) self._parse(512, onheader) oncontinue() } var onpaxglobalheader = function () { var size = self._header.size self._paxGlobal = headers.decodePax(b.slice(0, size)) b.consume(size) onstreamend() } var onpaxheader = function () { var size = self._header.size self._pax = headers.decodePax(b.slice(0, size)) if (self._paxGlobal) self._pax = Object.assign({}, self._paxGlobal, self._pax) b.consume(size) onstreamend() } var ongnulongpath = function () { var size = self._header.size this._gnuLongPath = headers.decodeLongPath(b.slice(0, size), opts.filenameEncoding) b.consume(size) onstreamend() } var ongnulonglinkpath = function () { var size = self._header.size this._gnuLongLinkPath = headers.decodeLongPath(b.slice(0, size), opts.filenameEncoding) b.consume(size) onstreamend() } var onheader = function () { var offset = self._offset var header try { header = self._header = headers.decode(b.slice(0, 512), opts.filenameEncoding, opts.allowUnknownFormat) } catch (err) { self.emit('error', err) } b.consume(512) if (!header) { self._parse(512, onheader) oncontinue() return } if (header.type === 'gnu-long-path') { self._parse(header.size, ongnulongpath) oncontinue() return } if (header.type === 'gnu-long-link-path') { self._parse(header.size, ongnulonglinkpath) oncontinue() return } if (header.type === 'pax-global-header') { self._parse(header.size, onpaxglobalheader) oncontinue() return } if (header.type === 'pax-header') { self._parse(header.size, onpaxheader) oncontinue() return } if (self._gnuLongPath) { header.name = self._gnuLongPath self._gnuLongPath = null } if (self._gnuLongLinkPath) { header.linkname = self._gnuLongLinkPath self._gnuLongLinkPath = null } if (self._pax) { self._header = header = mixinPax(header, self._pax) self._pax = null } self._locked = true if (!header.size || header.type === 'directory') { self._parse(512, onheader) self.emit('entry', header, emptyStream(self, offset), onunlock) return } self._stream = new Source(self, offset) self.emit('entry', header, self._stream, onunlock) self._parse(header.size, onstreamend) oncontinue() } this._onheader = onheader this._parse(512, onheader) } util.inherits(Extract, Writable) Extract.prototype.destroy = function (err) { if (this._destroyed) return this._destroyed = true if (err) this.emit('error', err) this.emit('close') if (this._stream) this._stream.emit('close') } Extract.prototype._parse = function (size, onparse) { if (this._destroyed) return this._offset += size this._missing = size if (onparse === this._onheader) this._partial = false this._onparse = onparse } Extract.prototype._continue = function () { if (this._destroyed) return var cb = this._cb this._cb = noop if (this._overflow) this._write(this._overflow, undefined, cb) else cb() } Extract.prototype._write = function (data, enc, cb) { if (this._destroyed) return var s = this._stream var b = this._buffer var missing = this._missing if (data.length) this._partial = true // we do not reach end-of-chunk now. just forward it if (data.length < missing) { this._missing -= data.length this._overflow = null if (s) return s.write(data, cb) b.append(data) return cb() } // end-of-chunk. the parser should call cb. this._cb = cb this._missing = 0 var overflow = null if (data.length > missing) { overflow = data.slice(missing) data = data.slice(0, missing) } if (s) s.end(data) else b.append(data) this._overflow = overflow this._onparse() } Extract.prototype._final = function (cb) { if (this._partial) return this.destroy(new Error('Unexpected end of data')) cb() } module.exports = Extract