Express_Crud_Example/node_modules/graceful-fs/polyfills.js
2022-01-28 22:33:42 +01:00

349 lines
9.5 KiB
JavaScript

var constants = require('constants')
var origCwd = process.cwd
var cwd = null
var platform = process.env.GRACEFUL_FS_PLATFORM || process.platform
process.cwd = function() {
if (!cwd)
cwd = origCwd.call(process)
return cwd
}
try {
process.cwd()
} catch (er) {}
// This check is needed until node.js 12 is required
if (typeof process.chdir === 'function') {
var chdir = process.chdir
process.chdir = function (d) {
cwd = null
chdir.call(process, d)
}
if (Object.setPrototypeOf) Object.setPrototypeOf(process.chdir, chdir)
}
module.exports = patch
function patch (fs) {
// (re-)implement some things that are known busted or missing.
// lchmod, broken prior to 0.6.2
// back-port the fix here.
if (constants.hasOwnProperty('O_SYMLINK') &&
process.version.match(/^v0\.6\.[0-2]|^v0\.5\./)) {
patchLchmod(fs)
}
// lutimes implementation, or no-op
if (!fs.lutimes) {
patchLutimes(fs)
}
// https://github.com/isaacs/node-graceful-fs/issues/4
// Chown should not fail on einval or eperm if non-root.
// It should not fail on enosys ever, as this just indicates
// that a fs doesn't support the intended operation.
fs.chown = chownFix(fs.chown)
fs.fchown = chownFix(fs.fchown)
fs.lchown = chownFix(fs.lchown)
fs.chmod = chmodFix(fs.chmod)
fs.fchmod = chmodFix(fs.fchmod)
fs.lchmod = chmodFix(fs.lchmod)
fs.chownSync = chownFixSync(fs.chownSync)
fs.fchownSync = chownFixSync(fs.fchownSync)
fs.lchownSync = chownFixSync(fs.lchownSync)
fs.chmodSync = chmodFixSync(fs.chmodSync)
fs.fchmodSync = chmodFixSync(fs.fchmodSync)
fs.lchmodSync = chmodFixSync(fs.lchmodSync)
fs.stat = statFix(fs.stat)
fs.fstat = statFix(fs.fstat)
fs.lstat = statFix(fs.lstat)
fs.statSync = statFixSync(fs.statSync)
fs.fstatSync = statFixSync(fs.fstatSync)
fs.lstatSync = statFixSync(fs.lstatSync)
// if lchmod/lchown do not exist, then make them no-ops
if (!fs.lchmod) {
fs.lchmod = function (path, mode, cb) {
if (cb) process.nextTick(cb)
}
fs.lchmodSync = function () {}
}
if (!fs.lchown) {
fs.lchown = function (path, uid, gid, cb) {
if (cb) process.nextTick(cb)
}
fs.lchownSync = function () {}
}
// on Windows, A/V software can lock the directory, causing this
// to fail with an EACCES or EPERM if the directory contains newly
// created files. Try again on failure, for up to 60 seconds.
// Set the timeout this long because some Windows Anti-Virus, such as Parity
// bit9, may lock files for up to a minute, causing npm package install
// failures. Also, take care to yield the scheduler. Windows scheduling gives
// CPU to a busy looping process, which can cause the program causing the lock
// contention to be starved of CPU by node, so the contention doesn't resolve.
if (platform === "win32") {
fs.rename = (function (fs$rename) { return function (from, to, cb) {
var start = Date.now()
var backoff = 0;
fs$rename(from, to, function CB (er) {
if (er
&& (er.code === "EACCES" || er.code === "EPERM")
&& Date.now() - start < 60000) {
setTimeout(function() {
fs.stat(to, function (stater, st) {
if (stater && stater.code === "ENOENT")
fs$rename(from, to, CB);
else
cb(er)
})
}, backoff)
if (backoff < 100)
backoff += 10;
return;
}
if (cb) cb(er)
})
}})(fs.rename)
}
// if read() returns EAGAIN, then just try it again.
fs.read = (function (fs$read) {
function read (fd, buffer, offset, length, position, callback_) {
var callback
if (callback_ && typeof callback_ === 'function') {
var eagCounter = 0
callback = function (er, _, __) {
if (er && er.code === 'EAGAIN' && eagCounter < 10) {
eagCounter ++
return fs$read.call(fs, fd, buffer, offset, length, position, callback)
}
callback_.apply(this, arguments)
}
}
return fs$read.call(fs, fd, buffer, offset, length, position, callback)
}
// This ensures `util.promisify` works as it does for native `fs.read`.
if (Object.setPrototypeOf) Object.setPrototypeOf(read, fs$read)
return read
})(fs.read)
fs.readSync = (function (fs$readSync) { return function (fd, buffer, offset, length, position) {
var eagCounter = 0
while (true) {
try {
return fs$readSync.call(fs, fd, buffer, offset, length, position)
} catch (er) {
if (er.code === 'EAGAIN' && eagCounter < 10) {
eagCounter ++
continue
}
throw er
}
}
}})(fs.readSync)
function patchLchmod (fs) {
fs.lchmod = function (path, mode, callback) {
fs.open( path
, constants.O_WRONLY | constants.O_SYMLINK
, mode
, function (err, fd) {
if (err) {
if (callback) callback(err)
return
}
// prefer to return the chmod error, if one occurs,
// but still try to close, and report closing errors if they occur.
fs.fchmod(fd, mode, function (err) {
fs.close(fd, function(err2) {
if (callback) callback(err || err2)
})
})
})
}
fs.lchmodSync = function (path, mode) {
var fd = fs.openSync(path, constants.O_WRONLY | constants.O_SYMLINK, mode)
// prefer to return the chmod error, if one occurs,
// but still try to close, and report closing errors if they occur.
var threw = true
var ret
try {
ret = fs.fchmodSync(fd, mode)
threw = false
} finally {
if (threw) {
try {
fs.closeSync(fd)
} catch (er) {}
} else {
fs.closeSync(fd)
}
}
return ret
}
}
function patchLutimes (fs) {
if (constants.hasOwnProperty("O_SYMLINK")) {
fs.lutimes = function (path, at, mt, cb) {
fs.open(path, constants.O_SYMLINK, function (er, fd) {
if (er) {
if (cb) cb(er)
return
}
fs.futimes(fd, at, mt, function (er) {
fs.close(fd, function (er2) {
if (cb) cb(er || er2)
})
})
})
}
fs.lutimesSync = function (path, at, mt) {
var fd = fs.openSync(path, constants.O_SYMLINK)
var ret
var threw = true
try {
ret = fs.futimesSync(fd, at, mt)
threw = false
} finally {
if (threw) {
try {
fs.closeSync(fd)
} catch (er) {}
} else {
fs.closeSync(fd)
}
}
return ret
}
} else {
fs.lutimes = function (_a, _b, _c, cb) { if (cb) process.nextTick(cb) }
fs.lutimesSync = function () {}
}
}
function chmodFix (orig) {
if (!orig) return orig
return function (target, mode, cb) {
return orig.call(fs, target, mode, function (er) {
if (chownErOk(er)) er = null
if (cb) cb.apply(this, arguments)
})
}
}
function chmodFixSync (orig) {
if (!orig) return orig
return function (target, mode) {
try {
return orig.call(fs, target, mode)
} catch (er) {
if (!chownErOk(er)) throw er
}
}
}
function chownFix (orig) {
if (!orig) return orig
return function (target, uid, gid, cb) {
return orig.call(fs, target, uid, gid, function (er) {
if (chownErOk(er)) er = null
if (cb) cb.apply(this, arguments)
})
}
}
function chownFixSync (orig) {
if (!orig) return orig
return function (target, uid, gid) {
try {
return orig.call(fs, target, uid, gid)
} catch (er) {
if (!chownErOk(er)) throw er
}
}
}
function statFix (orig) {
if (!orig) return orig
// Older versions of Node erroneously returned signed integers for
// uid + gid.
return function (target, options, cb) {
if (typeof options === 'function') {
cb = options
options = null
}
function callback (er, stats) {
if (stats) {
if (stats.uid < 0) stats.uid += 0x100000000
if (stats.gid < 0) stats.gid += 0x100000000
}
if (cb) cb.apply(this, arguments)
}
return options ? orig.call(fs, target, options, callback)
: orig.call(fs, target, callback)
}
}
function statFixSync (orig) {
if (!orig) return orig
// Older versions of Node erroneously returned signed integers for
// uid + gid.
return function (target, options) {
var stats = options ? orig.call(fs, target, options)
: orig.call(fs, target)
if (stats) {
if (stats.uid < 0) stats.uid += 0x100000000
if (stats.gid < 0) stats.gid += 0x100000000
}
return stats;
}
}
// ENOSYS means that the fs doesn't support the op. Just ignore
// that, because it doesn't matter.
//
// if there's no getuid, or if getuid() is something other
// than 0, and the error is EINVAL or EPERM, then just ignore
// it.
//
// This specific case is a silent failure in cp, install, tar,
// and most other unix tools that manage permissions.
//
// When running as root, or if other types of errors are
// encountered, then it's strict.
function chownErOk (er) {
if (!er)
return true
if (er.code === "ENOSYS")
return true
var nonroot = !process.getuid || process.getuid() !== 0
if (nonroot) {
if (er.code === "EINVAL" || er.code === "EPERM")
return true
}
return false
}
}