* first action! (#1)

node_modules/tar/lib/pax.js

@@ -0,0 +1,146 @@
+'use strict'
+const Buffer = require('./buffer.js')
+const Header = require('./header.js')
+const path = require('path')
+
+class Pax {
+  constructor (obj, global) {
+    this.atime = obj.atime || null
+    this.charset = obj.charset || null
+    this.comment = obj.comment || null
+    this.ctime = obj.ctime || null
+    this.gid = obj.gid || null
+    this.gname = obj.gname || null
+    this.linkpath = obj.linkpath || null
+    this.mtime = obj.mtime || null
+    this.path = obj.path || null
+    this.size = obj.size || null
+    this.uid = obj.uid || null
+    this.uname = obj.uname || null
+    this.dev = obj.dev || null
+    this.ino = obj.ino || null
+    this.nlink = obj.nlink || null
+    this.global = global || false
+  }
+
+  encode () {
+    const body = this.encodeBody()
+    if (body === '')
+      return null
+
+    const bodyLen = Buffer.byteLength(body)
+    // round up to 512 bytes
+    // add 512 for header
+    const bufLen = 512 * Math.ceil(1 + bodyLen / 512)
+    const buf = Buffer.allocUnsafe(bufLen)
+
+    // 0-fill the header section, it might not hit every field
+    for (let i = 0; i < 512; i++) {
+      buf[i] = 0
+    }
+
+    new Header({
+      // XXX split the path
+      // then the path should be PaxHeader + basename, but less than 99,
+      // prepend with the dirname
+      path: ('PaxHeader/' + path.basename(this.path)).slice(0, 99),
+      mode: this.mode || 0o644,
+      uid: this.uid || null,
+      gid: this.gid || null,
+      size: bodyLen,
+      mtime: this.mtime || null,
+      type: this.global ? 'GlobalExtendedHeader' : 'ExtendedHeader',
+      linkpath: '',
+      uname: this.uname || '',
+      gname: this.gname || '',
+      devmaj: 0,
+      devmin: 0,
+      atime: this.atime || null,
+      ctime: this.ctime || null
+    }).encode(buf)
+
+    buf.write(body, 512, bodyLen, 'utf8')
+
+    // null pad after the body
+    for (let i = bodyLen + 512; i < buf.length; i++) {
+      buf[i] = 0
+    }
+
+    return buf
+  }
+
+  encodeBody () {
+    return (
+      this.encodeField('path') +
+      this.encodeField('ctime') +
+      this.encodeField('atime') +
+      this.encodeField('dev') +
+      this.encodeField('ino') +
+      this.encodeField('nlink') +
+      this.encodeField('charset') +
+      this.encodeField('comment') +
+      this.encodeField('gid') +
+      this.encodeField('gname') +
+      this.encodeField('linkpath') +
+      this.encodeField('mtime') +
+      this.encodeField('size') +
+      this.encodeField('uid') +
+      this.encodeField('uname')
+    )
+  }
+
+  encodeField (field) {
+    if (this[field] === null || this[field] === undefined)
+      return ''
+    const v = this[field] instanceof Date ? this[field].getTime() / 1000
+      : this[field]
+    const s = ' ' +
+      (field === 'dev' || field === 'ino' || field === 'nlink'
+       ? 'SCHILY.' : '') +
+      field + '=' + v + '\n'
+    const byteLen = Buffer.byteLength(s)
+    // the digits includes the length of the digits in ascii base-10
+    // so if it's 9 characters, then adding 1 for the 9 makes it 10
+    // which makes it 11 chars.
+    let digits = Math.floor(Math.log(byteLen) / Math.log(10)) + 1
+    if (byteLen + digits >= Math.pow(10, digits))
+      digits += 1
+    const len = digits + byteLen
+    return len + s
+  }
+}
+
+Pax.parse = (string, ex, g) => new Pax(merge(parseKV(string), ex), g)
+
+const merge = (a, b) =>
+  b ? Object.keys(a).reduce((s, k) => (s[k] = a[k], s), b) : a
+
+const parseKV = string =>
+  string
+    .replace(/\n$/, '')
+    .split('\n')
+    .reduce(parseKVLine, Object.create(null))
+
+const parseKVLine = (set, line) => {
+  const n = parseInt(line, 10)
+
+  // XXX Values with \n in them will fail this.
+  // Refactor to not be a naive line-by-line parse.
+  if (n !== Buffer.byteLength(line) + 1)
+    return set
+
+  line = line.substr((n + ' ').length)
+  const kv = line.split('=')
+  const k = kv.shift().replace(/^SCHILY\.(dev|ino|nlink)/, '$1')
+  if (!k)
+    return set
+
+  const v = kv.join('=')
+  set[k] = /^([A-Z]+\.)?([mac]|birth|creation)time$/.test(k)
+    ?  new Date(v * 1000)
+    : /^[0-9]+$/.test(v) ? +v
+    : v
+  return set
+}
+
+module.exports = Pax