electron/atom/common/lib/asar.coffee
2016-01-12 16:22:34 -08:00

394 lines
12 KiB
CoffeeScript

asar = process.binding 'atom_common_asar'
child_process = require 'child_process'
path = require 'path'
util = require 'util'
### Cache asar archive objects. ###
cachedArchives = {}
getOrCreateArchive = (p) ->
archive = cachedArchives[p]
return archive if archive?
archive = asar.createArchive p
return false unless archive
cachedArchives[p] = archive
### Clean cache on quit. ###
process.on 'exit', ->
archive.destroy() for own p, archive of cachedArchives
### Separate asar package's path from full path. ###
splitPath = (p) ->
### shortcut to disable asar. ###
return [false] if process.noAsar
return [false] if typeof p isnt 'string'
return [true, p, ''] if p.substr(-5) is '.asar'
p = path.normalize p
index = p.lastIndexOf ".asar#{path.sep}"
return [false] if index is -1
[true, p.substr(0, index + 5), p.substr(index + 6)]
### Convert asar archive's Stats object to fs's Stats object. ###
nextInode = 0
uid = if process.getuid? then process.getuid() else 0
gid = if process.getgid? then process.getgid() else 0
fakeTime = new Date()
asarStatsToFsStats = (stats) ->
{
dev: 1,
ino: ++nextInode,
mode: 33188,
nlink: 1,
uid: uid,
gid: gid,
rdev: 0,
atime: stats.atime || fakeTime,
birthtime: stats.birthtime || fakeTime,
mtime: stats.mtime || fakeTime,
ctime: stats.ctime || fakeTime,
size: stats.size,
isFile: -> stats.isFile
isDirectory: -> stats.isDirectory
isSymbolicLink: -> stats.isLink
isBlockDevice: -> false
isCharacterDevice: -> false
isFIFO: -> false
isSocket: -> false
}
### Create a ENOENT error. ###
notFoundError = (asarPath, filePath, callback) ->
error = new Error("ENOENT, #{filePath} not found in #{asarPath}")
error.code = "ENOENT"
error.errno = -2
unless typeof callback is 'function'
throw error
process.nextTick -> callback error
### Create a ENOTDIR error. ###
notDirError = (callback) ->
error = new Error('ENOTDIR, not a directory')
error.code = 'ENOTDIR'
error.errno = -20
unless typeof callback is 'function'
throw error
process.nextTick -> callback error
### Create invalid archive error. ###
invalidArchiveError = (asarPath, callback) ->
error = new Error("Invalid package #{asarPath}")
unless typeof callback is 'function'
throw error
process.nextTick -> callback error
### Override APIs that rely on passing file path instead of content to C++. ###
overrideAPISync = (module, name, arg = 0) ->
old = module[name]
module[name] = ->
p = arguments[arg]
[isAsar, asarPath, filePath] = splitPath p
return old.apply this, arguments unless isAsar
archive = getOrCreateArchive asarPath
invalidArchiveError asarPath unless archive
newPath = archive.copyFileOut filePath
notFoundError asarPath, filePath unless newPath
arguments[arg] = newPath
old.apply this, arguments
overrideAPI = (module, name, arg = 0) ->
old = module[name]
module[name] = ->
p = arguments[arg]
[isAsar, asarPath, filePath] = splitPath p
return old.apply this, arguments unless isAsar
callback = arguments[arguments.length - 1]
return overrideAPISync module, name, arg unless typeof callback is 'function'
archive = getOrCreateArchive asarPath
return invalidArchiveError asarPath, callback unless archive
newPath = archive.copyFileOut filePath
return notFoundError asarPath, filePath, callback unless newPath
arguments[arg] = newPath
old.apply this, arguments
### Override fs APIs. ###
exports.wrapFsWithAsar = (fs) ->
lstatSync = fs.lstatSync
fs.lstatSync = (p) ->
[isAsar, asarPath, filePath] = splitPath p
return lstatSync p unless isAsar
archive = getOrCreateArchive asarPath
invalidArchiveError asarPath unless archive
stats = archive.stat filePath
notFoundError asarPath, filePath unless stats
asarStatsToFsStats stats
lstat = fs.lstat
fs.lstat = (p, callback) ->
[isAsar, asarPath, filePath] = splitPath p
return lstat p, callback unless isAsar
archive = getOrCreateArchive asarPath
return invalidArchiveError asarPath, callback unless archive
stats = getOrCreateArchive(asarPath).stat filePath
return notFoundError asarPath, filePath, callback unless stats
process.nextTick -> callback null, asarStatsToFsStats stats
statSync = fs.statSync
fs.statSync = (p) ->
[isAsar, asarPath, filePath] = splitPath p
return statSync p unless isAsar
### Do not distinguish links for now. ###
fs.lstatSync p
stat = fs.stat
fs.stat = (p, callback) ->
[isAsar, asarPath, filePath] = splitPath p
return stat p, callback unless isAsar
### Do not distinguish links for now. ###
process.nextTick -> fs.lstat p, callback
statSyncNoException = fs.statSyncNoException
fs.statSyncNoException = (p) ->
[isAsar, asarPath, filePath] = splitPath p
return statSyncNoException p unless isAsar
archive = getOrCreateArchive asarPath
return false unless archive
stats = archive.stat filePath
return false unless stats
asarStatsToFsStats stats
realpathSync = fs.realpathSync
fs.realpathSync = (p) ->
[isAsar, asarPath, filePath] = splitPath p
return realpathSync.apply this, arguments unless isAsar
archive = getOrCreateArchive asarPath
invalidArchiveError asarPath unless archive
real = archive.realpath filePath
notFoundError asarPath, filePath if real is false
path.join realpathSync(asarPath), real
realpath = fs.realpath
fs.realpath = (p, cache, callback) ->
[isAsar, asarPath, filePath] = splitPath p
return realpath.apply this, arguments unless isAsar
if typeof cache is 'function'
callback = cache
cache = undefined
archive = getOrCreateArchive asarPath
return invalidArchiveError asarPath, callback unless archive
real = archive.realpath filePath
if real is false
return notFoundError asarPath, filePath, callback
realpath asarPath, (err, p) ->
return callback err if err
callback null, path.join(p, real)
exists = fs.exists
fs.exists = (p, callback) ->
[isAsar, asarPath, filePath] = splitPath p
return exists p, callback unless isAsar
archive = getOrCreateArchive asarPath
return invalidArchiveError asarPath, callback unless archive
process.nextTick -> callback archive.stat(filePath) isnt false
existsSync = fs.existsSync
fs.existsSync = (p) ->
[isAsar, asarPath, filePath] = splitPath p
return existsSync p unless isAsar
archive = getOrCreateArchive asarPath
return false unless archive
archive.stat(filePath) isnt false
open = fs.open
readFile = fs.readFile
fs.readFile = (p, options, callback) ->
[isAsar, asarPath, filePath] = splitPath p
return readFile.apply this, arguments unless isAsar
if typeof options is 'function'
callback = options
options = undefined
archive = getOrCreateArchive asarPath
return invalidArchiveError asarPath, callback unless archive
info = archive.getFileInfo filePath
return notFoundError asarPath, filePath, callback unless info
if info.size is 0
return process.nextTick -> callback null, new Buffer(0)
if info.unpacked
realPath = archive.copyFileOut filePath
return fs.readFile realPath, options, callback
if not options
options = encoding: null
else if util.isString options
options = encoding: options
else if not util.isObject options
throw new TypeError('Bad arguments')
encoding = options.encoding
buffer = new Buffer(info.size)
fd = archive.getFd()
return notFoundError asarPath, filePath, callback unless fd >= 0
fs.read fd, buffer, 0, info.size, info.offset, (error) ->
callback error, if encoding then buffer.toString encoding else buffer
openSync = fs.openSync
readFileSync = fs.readFileSync
fs.readFileSync = (p, opts) ->
### this allows v8 to optimize this function ###
options = opts
[isAsar, asarPath, filePath] = splitPath p
return readFileSync.apply this, arguments unless isAsar
archive = getOrCreateArchive asarPath
invalidArchiveError asarPath unless archive
info = archive.getFileInfo filePath
notFoundError asarPath, filePath unless info
if info.size is 0
return if options then '' else new Buffer(0)
if info.unpacked
realPath = archive.copyFileOut filePath
return fs.readFileSync realPath, options
if not options
options = encoding: null
else if util.isString options
options = encoding: options
else if not util.isObject options
throw new TypeError('Bad arguments')
encoding = options.encoding
buffer = new Buffer(info.size)
fd = archive.getFd()
notFoundError asarPath, filePath unless fd >= 0
fs.readSync fd, buffer, 0, info.size, info.offset
if encoding then buffer.toString encoding else buffer
readdir = fs.readdir
fs.readdir = (p, callback) ->
[isAsar, asarPath, filePath] = splitPath p
return readdir.apply this, arguments unless isAsar
archive = getOrCreateArchive asarPath
return invalidArchiveError asarPath, callback unless archive
files = archive.readdir filePath
return notFoundError asarPath, filePath, callback unless files
process.nextTick -> callback null, files
readdirSync = fs.readdirSync
fs.readdirSync = (p) ->
[isAsar, asarPath, filePath] = splitPath p
return readdirSync.apply this, arguments unless isAsar
archive = getOrCreateArchive asarPath
invalidArchiveError asarPath unless archive
files = archive.readdir filePath
notFoundError asarPath, filePath unless files
files
internalModuleReadFile = process.binding('fs').internalModuleReadFile
process.binding('fs').internalModuleReadFile = (p) ->
[isAsar, asarPath, filePath] = splitPath p
return internalModuleReadFile p unless isAsar
archive = getOrCreateArchive asarPath
return undefined unless archive
info = archive.getFileInfo filePath
return undefined unless info
return '' if info.size is 0
if info.unpacked
realPath = archive.copyFileOut filePath
return fs.readFileSync realPath, encoding: 'utf8'
buffer = new Buffer(info.size)
fd = archive.getFd()
return undefined unless fd >= 0
fs.readSync fd, buffer, 0, info.size, info.offset
buffer.toString 'utf8'
internalModuleStat = process.binding('fs').internalModuleStat
process.binding('fs').internalModuleStat = (p) ->
[isAsar, asarPath, filePath] = splitPath p
return internalModuleStat p unless isAsar
archive = getOrCreateArchive asarPath
### -ENOENT ###
return -34 unless archive
stats = archive.stat filePath
### -ENOENT ###
return -34 unless stats
if stats.isDirectory then return 1 else return 0
###
Calling mkdir for directory inside asar archive should throw ENOTDIR
error, but on Windows it throws ENOENT.
This is to work around the recursive looping bug of mkdirp since it is
widely used.
###
if process.platform is 'win32'
mkdir = fs.mkdir
fs.mkdir = (p, mode, callback) ->
callback = mode if typeof mode is 'function'
[isAsar, asarPath, filePath] = splitPath p
return notDirError callback if isAsar and filePath.length
mkdir p, mode, callback
mkdirSync = fs.mkdirSync
fs.mkdirSync = (p, mode) ->
[isAsar, asarPath, filePath] = splitPath p
notDirError() if isAsar and filePath.length
mkdirSync p, mode
overrideAPI fs, 'open'
overrideAPI child_process, 'execFile'
overrideAPISync process, 'dlopen', 1
overrideAPISync require('module')._extensions, '.node', 1
overrideAPISync fs, 'openSync'
overrideAPISync child_process, 'execFileSync'