atcheck/lsscanner/new_ubuntu/node_modules/tar/lib/replace.js

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2019-12-16 18:42:21 +01:00
'use strict'
const Buffer = require('./buffer.js')
// tar -r
const hlo = require('./high-level-opt.js')
const Pack = require('./pack.js')
const Parse = require('./parse.js')
const fs = require('fs')
const fsm = require('fs-minipass')
const t = require('./list.js')
const path = require('path')
// starting at the head of the file, read a Header
// If the checksum is invalid, that's our position to start writing
// If it is, jump forward by the specified size (round up to 512)
// and try again.
// Write the new Pack stream starting there.
const Header = require('./header.js')
const r = module.exports = (opt_, files, cb) => {
const opt = hlo(opt_)
if (!opt.file)
throw new TypeError('file is required')
if (opt.gzip)
throw new TypeError('cannot append to compressed archives')
if (!files || !Array.isArray(files) || !files.length)
throw new TypeError('no files or directories specified')
files = Array.from(files)
return opt.sync ? replaceSync(opt, files)
: replace(opt, files, cb)
}
const replaceSync = (opt, files) => {
const p = new Pack.Sync(opt)
let threw = true
let fd
let position
try {
try {
fd = fs.openSync(opt.file, 'r+')
} catch (er) {
if (er.code === 'ENOENT')
fd = fs.openSync(opt.file, 'w+')
else
throw er
}
const st = fs.fstatSync(fd)
const headBuf = Buffer.alloc(512)
POSITION: for (position = 0; position < st.size; position += 512) {
for (let bufPos = 0, bytes = 0; bufPos < 512; bufPos += bytes) {
bytes = fs.readSync(
fd, headBuf, bufPos, headBuf.length - bufPos, position + bufPos
)
if (position === 0 && headBuf[0] === 0x1f && headBuf[1] === 0x8b)
throw new Error('cannot append to compressed archives')
if (!bytes)
break POSITION
}
let h = new Header(headBuf)
if (!h.cksumValid)
break
let entryBlockSize = 512 * Math.ceil(h.size / 512)
if (position + entryBlockSize + 512 > st.size)
break
// the 512 for the header we just parsed will be added as well
// also jump ahead all the blocks for the body
position += entryBlockSize
if (opt.mtimeCache)
opt.mtimeCache.set(h.path, h.mtime)
}
threw = false
streamSync(opt, p, position, fd, files)
} finally {
if (threw)
try { fs.closeSync(fd) } catch (er) {}
}
}
const streamSync = (opt, p, position, fd, files) => {
const stream = new fsm.WriteStreamSync(opt.file, {
fd: fd,
start: position
})
p.pipe(stream)
addFilesSync(p, files)
}
const replace = (opt, files, cb) => {
files = Array.from(files)
const p = new Pack(opt)
const getPos = (fd, size, cb_) => {
const cb = (er, pos) => {
if (er)
fs.close(fd, _ => cb_(er))
else
cb_(null, pos)
}
let position = 0
if (size === 0)
return cb(null, 0)
let bufPos = 0
const headBuf = Buffer.alloc(512)
const onread = (er, bytes) => {
if (er)
return cb(er)
bufPos += bytes
if (bufPos < 512 && bytes)
return fs.read(
fd, headBuf, bufPos, headBuf.length - bufPos,
position + bufPos, onread
)
if (position === 0 && headBuf[0] === 0x1f && headBuf[1] === 0x8b)
return cb(new Error('cannot append to compressed archives'))
// truncated header
if (bufPos < 512)
return cb(null, position)
const h = new Header(headBuf)
if (!h.cksumValid)
return cb(null, position)
const entryBlockSize = 512 * Math.ceil(h.size / 512)
if (position + entryBlockSize + 512 > size)
return cb(null, position)
position += entryBlockSize + 512
if (position >= size)
return cb(null, position)
if (opt.mtimeCache)
opt.mtimeCache.set(h.path, h.mtime)
bufPos = 0
fs.read(fd, headBuf, 0, 512, position, onread)
}
fs.read(fd, headBuf, 0, 512, position, onread)
}
const promise = new Promise((resolve, reject) => {
p.on('error', reject)
let flag = 'r+'
const onopen = (er, fd) => {
if (er && er.code === 'ENOENT' && flag === 'r+') {
flag = 'w+'
return fs.open(opt.file, flag, onopen)
}
if (er)
return reject(er)
fs.fstat(fd, (er, st) => {
if (er)
return reject(er)
getPos(fd, st.size, (er, position) => {
if (er)
return reject(er)
const stream = new fsm.WriteStream(opt.file, {
fd: fd,
start: position
})
p.pipe(stream)
stream.on('error', reject)
stream.on('close', resolve)
addFilesAsync(p, files)
})
})
}
fs.open(opt.file, flag, onopen)
})
return cb ? promise.then(cb, cb) : promise
}
const addFilesSync = (p, files) => {
files.forEach(file => {
if (file.charAt(0) === '@')
t({
file: path.resolve(p.cwd, file.substr(1)),
sync: true,
noResume: true,
onentry: entry => p.add(entry)
})
else
p.add(file)
})
p.end()
}
const addFilesAsync = (p, files) => {
while (files.length) {
const file = files.shift()
if (file.charAt(0) === '@')
return t({
file: path.resolve(p.cwd, file.substr(1)),
noResume: true,
onentry: entry => p.add(entry)
}).then(_ => addFilesAsync(p, files))
else
p.add(file)
}
p.end()
}