trouble-in-terror-town/node_modules/tar/lib/extract.js
Mikolaj 2bbacbea09 did some more work on networking and removed EOS in favor of LRM
did some more work on networking and removed EOS in favor of Light Reflective Mirror
2022-05-31 15:04:31 +02:00

107 lines
2.7 KiB
JavaScript

'use strict'
// tar -x
const hlo = require('./high-level-opt.js')
const Unpack = require('./unpack.js')
const fs = require('fs')
const fsm = require('fs-minipass')
const path = require('path')
const stripSlash = require('./strip-trailing-slashes.js')
module.exports = (opt_, files, cb) => {
if (typeof opt_ === 'function')
cb = opt_, files = null, opt_ = {}
else if (Array.isArray(opt_))
files = opt_, opt_ = {}
if (typeof files === 'function')
cb = files, files = null
if (!files)
files = []
else
files = Array.from(files)
const opt = hlo(opt_)
if (opt.sync && typeof cb === 'function')
throw new TypeError('callback not supported for sync tar functions')
if (!opt.file && typeof cb === 'function')
throw new TypeError('callback only supported with file option')
if (files.length)
filesFilter(opt, files)
return opt.file && opt.sync ? extractFileSync(opt)
: opt.file ? extractFile(opt, cb)
: opt.sync ? extractSync(opt)
: extract(opt)
}
// construct a filter that limits the file entries listed
// include child entries if a dir is included
const filesFilter = (opt, files) => {
const map = new Map(files.map(f => [stripSlash(f), true]))
const filter = opt.filter
const mapHas = (file, r) => {
const root = r || path.parse(file).root || '.'
const ret = file === root ? false
: map.has(file) ? map.get(file)
: mapHas(path.dirname(file), root)
map.set(file, ret)
return ret
}
opt.filter = filter
? (file, entry) => filter(file, entry) && mapHas(stripSlash(file))
: file => mapHas(stripSlash(file))
}
const extractFileSync = opt => {
const u = new Unpack.Sync(opt)
const file = opt.file
const stat = fs.statSync(file)
// This trades a zero-byte read() syscall for a stat
// However, it will usually result in less memory allocation
const readSize = opt.maxReadSize || 16 * 1024 * 1024
const stream = new fsm.ReadStreamSync(file, {
readSize: readSize,
size: stat.size,
})
stream.pipe(u)
}
const extractFile = (opt, cb) => {
const u = new Unpack(opt)
const readSize = opt.maxReadSize || 16 * 1024 * 1024
const file = opt.file
const p = new Promise((resolve, reject) => {
u.on('error', reject)
u.on('close', resolve)
// This trades a zero-byte read() syscall for a stat
// However, it will usually result in less memory allocation
fs.stat(file, (er, stat) => {
if (er)
reject(er)
else {
const stream = new fsm.ReadStream(file, {
readSize: readSize,
size: stat.size,
})
stream.on('error', reject)
stream.pipe(u)
}
})
})
return cb ? p.then(cb, cb) : p
}
const extractSync = opt => new Unpack.Sync(opt)
const extract = opt => new Unpack(opt)