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// field paths that every tar file must have.
// header is padded to 512 bytes.
var f = 0
, fields = {}
, path = fields.path = f++
, mode = fields.mode = f++
, uid = fields.uid = f++
, gid = fields.gid = f++
, size = fields.size = f++
, mtime = fields.mtime = f++
, cksum = fields.cksum = f++
, type = fields.type = f++
, linkpath = fields.linkpath = f++
, headerSize = 512
, blockSize = 512
, fieldSize = []
fieldSize[path] = 100
fieldSize[mode] = 8
fieldSize[uid] = 8
fieldSize[gid] = 8
fieldSize[size] = 12
fieldSize[mtime] = 12
fieldSize[cksum] = 8
fieldSize[type] = 1
fieldSize[linkpath] = 100
// "ustar\0" may introduce another bunch of headers.
// these are optional, and will be nulled out if not present.
var ustar = fields.ustar = f++
, ustarver = fields.ustarver = f++
, uname = fields.uname = f++
, gname = fields.gname = f++
, devmaj = fields.devmaj = f++
, devmin = fields.devmin = f++
, prefix = fields.prefix = f++
, fill = fields.fill = f++
// terminate fields.
fields[f] = null
fieldSize[ustar] = 6
fieldSize[ustarver] = 2
fieldSize[uname] = 32
fieldSize[gname] = 32
fieldSize[devmaj] = 8
fieldSize[devmin] = 8
fieldSize[prefix] = 155
fieldSize[fill] = 12
// nb: prefix field may in fact be 130 bytes of prefix,
// a null char, 12 bytes for atime, 12 bytes for ctime.
//
// To recognize this format:
// 1. prefix[130] === ' ' or '\0'
// 2. atime and ctime are octal numeric values
// 3. atime and ctime have ' ' in their last byte
var fieldEnds = {}
, fieldOffs = {}
, fe = 0
for (var i = 0; i < f; i ++) {
fieldOffs[i] = fe
fieldEnds[i] = (fe += fieldSize[i])
}
// build a translation table of field paths.
Object.keys(fields).forEach(function (f) {
if (fields[f] !== null) fields[fields[f]] = f
})
// different values of the 'type' field
// paths match the values of Stats.isX() functions, where appropriate
var types =
{ 0: "File"
, "\0": "OldFile" // like 0
, "": "OldFile"
, 1: "Link"
, 2: "SymbolicLink"
, 3: "CharacterDevice"
, 4: "BlockDevice"
, 5: "Directory"
, 6: "FIFO"
, 7: "ContiguousFile" // like 0
// posix headers
, g: "GlobalExtendedHeader" // k=v for the rest of the archive
, x: "ExtendedHeader" // k=v for the next file
// vendor-specific stuff
, A: "SolarisACL" // skip
, D: "GNUDumpDir" // like 5, but with data, which should be skipped
, I: "Inode" // metadata only, skip
, K: "NextFileHasLongLinkpath" // data = link path of next file
, L: "NextFileHasLongPath" // data = path of next file
, M: "ContinuationFile" // skip
, N: "OldGnuLongPath" // like L
, S: "SparseFile" // skip
, V: "TapeVolumeHeader" // skip
, X: "OldExtendedHeader" // like x
}
Object.keys(types).forEach(function (t) {
types[types[t]] = types[types[t]] || t
})
// values for the mode field
var modes =
{ suid: 04000 // set uid on extraction
, sgid: 02000 // set gid on extraction
, svtx: 01000 // set restricted deletion flag on dirs on extraction
, uread: 0400
, uwrite: 0200
, uexec: 0100
, gread: 040
, gwrite: 020
, gexec: 010
, oread: 4
, owrite: 2
, oexec: 1
, all: 07777
}
var numeric =
{ mode: true
, uid: true
, gid: true
, size: true
, mtime: true
, devmaj: true
, devmin: true
, cksum: true
, atime: true
, ctime: true
, dev: true
, ino: true
, nlink: true
}
Object.keys(modes).forEach(function (t) {
modes[modes[t]] = modes[modes[t]] || t
})
var knownExtended =
{ atime: true
, charset: true
, comment: true
, ctime: true
, gid: true
, gname: true
, linkpath: true
, mtime: true
, path: true
, realtime: true
, security: true
, size: true
, uid: true
, uname: true }
exports.fields = fields
exports.fieldSize = fieldSize
exports.fieldOffs = fieldOffs
exports.fieldEnds = fieldEnds
exports.types = types
exports.modes = modes
exports.numeric = numeric
exports.headerSize = headerSize
exports.blockSize = blockSize
exports.knownExtended = knownExtended
exports.Pack = require("./lib/pack.js")
exports.Parse = require("./lib/parse.js")
exports.Extract = require("./lib/extract.js")
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