// Hello, and welcome to hacking node.js!

//

// This file is invoked by node::Load in src/node.cc, and responsible for

// bootstrapping the node.js core. Special caution is given to the performance

// of the startup process, so many dependencies are invoked lazily.

'use strict';

(function(process) {

this.global = this;

function startup() {

var EventEmitter = NativeModule.require('events').EventEmitter;

process.__proto__ = Object.create(EventEmitter.prototype, {

constructor: {

value: process.constructor

}

});

EventEmitter.call(process);

process.EventEmitter = EventEmitter; // process.EventEmitter is deprecated

// do this good and early, since it handles errors.

startup.processFatal();

startup.globalVariables();

startup.globalTimeouts();

startup.globalConsole();

startup.processAssert();

startup.processConfig();

startup.processNextTick();

startup.processPromises();

startup.processStdio();

startup.processKillAndExit();

startup.processSignalHandlers();

// Do not initialize channel in debugger agent, it deletes env variable

// and the main thread won't see it.

if (process.argv[1] !== '--debug-agent')

startup.processChannel();

startup.processRawDebug();

process.argv[0] = process.execPath;

// There are various modes that Node can run in. The most common two

// are running from a script and running the REPL - but there are a few

// others like the debugger or running --eval arguments. Here we decide

// which mode we run in.

if (NativeModule.exists('_third_party_main')) {

// To allow people to extend Node in different ways, this hook allows

// one to drop a file lib/_third_party_main.js into the build

// directory which will be executed instead of Node's normal loading.

process.nextTick(function() {

NativeModule.require('_third_party_main');

});

} else if (process.argv[1] == 'debug') {

// Start the debugger agent

var d = NativeModule.require('_debugger');

d.start();

} else if (process.argv[1] == '--debug-agent') {

// Start the debugger agent

var d = NativeModule.require('_debug_agent');

d.start();

} else {

// There is user code to be run

// If this is a worker in cluster mode, start up the communication

// channel. This needs to be done before any user code gets executed

// (including preload modules).

if (process.argv[1] && process.env.NODE_UNIQUE_ID) {

var cluster = NativeModule.require('cluster');

cluster._setupWorker();

// Make sure it's not accidentally inherited by child processes.

delete process.env.NODE_UNIQUE_ID;

}

// Load any preload modules

if (process._preload_modules) {

var Module = NativeModule.require('module');

process._preload_modules.forEach(function(module) {

Module._load(module);

});

}

if (process._eval != null) {

// User passed '-e' or '--eval' arguments to Node.

evalScript('[eval]');

} else if (process.argv[1]) {

// make process.argv[1] into a full path

var path = NativeModule.require('path');

process.argv[1] = path.resolve(process.argv[1]);

var Module = NativeModule.require('module');

if (global.v8debug &&

process.execArgv.some(function(arg) {

return arg.match(/^--debug-brk(=[0-9]*)?$/);

})) {

// XXX Fix this terrible hack!

//

// Give the client program a few ticks to connect.

// Otherwise, there's a race condition where `node debug foo.js`

// will not be able to connect in time to catch the first

// breakpoint message on line 1.

//

// A better fix would be to somehow get a message from the

// global.v8debug object about a connection, and runMain when

// that occurs. --isaacs

var debugTimeout = +process.env.NODE_DEBUG_TIMEOUT || 50;

setTimeout(Module.runMain, debugTimeout);

} else {

// Main entry point into most programs:

Module.runMain();

}

} else {

var Module = NativeModule.require('module');

// If -i or --interactive were passed, or stdin is a TTY.

if (process._forceRepl || NativeModule.require('tty').isatty(0)) {

// REPL

Module.requireRepl().createRepl(process.env, function(err, repl) {

if (err) {

throw err;

}

repl.on('exit', function() {

if (repl._flushing) {

repl.pause();

return repl.once('flushHistory', function() {

process.exit();

});

}

process.exit();

});

});

} else {

// Read all of stdin - execute it.

process.stdin.setEncoding('utf8');

var code = '';

process.stdin.on('data', function(d) {

code += d;

});

process.stdin.on('end', function() {

process._eval = code;

evalScript('[stdin]');

});

}

}

}

}

startup.globalVariables = function() {

global.process = process;

global.global = global;

global.GLOBAL = global;

global.root = global;

global.Buffer = NativeModule.require('buffer').Buffer;

process.domain = null;

process._exiting = false;

};

startup.globalTimeouts = function() {

const timers = NativeModule.require('timers');

global.clearImmediate = timers.clearImmediate;

global.clearInterval = timers.clearInterval;

global.clearTimeout = timers.clearTimeout;

global.setImmediate = timers.setImmediate;

global.setInterval = timers.setInterval;

global.setTimeout = timers.setTimeout;

};

startup.globalConsole = function() {

global.__defineGetter__('console', function() {

return NativeModule.require('console');

});

};

startup._lazyConstants = null;

startup.lazyConstants = function() {

if (!startup._lazyConstants) {

startup._lazyConstants = process.binding('constants');

}

return startup._lazyConstants;

};

startup.processFatal = function() {

process._makeCallbackAbortOnUncaught = function() {

try {

return this[1].apply(this[0], arguments);

} catch (err) {

process._fatalException(err);

}

};

process._fatalException = function(er) {

var caught;

if (process.domain && process.domain._errorHandler)

caught = process.domain._errorHandler(er) || caught;

if (!caught)

caught = process.emit('uncaughtException', er);

// If someone handled it, then great. otherwise, die in C++ land

// since that means that we'll exit the process, emit the 'exit' event

if (!caught) {

try {

if (!process._exiting) {

process._exiting = true;

process.emit('exit', 1);

}

} catch (er) {

// nothing to be done about it at this point.

}

// if we handled an error, then make sure any ticks get processed

} else {

NativeModule.require('timers').setImmediate(process._tickCallback);

}

return caught;

};

};

var assert;

startup.processAssert = function() {

assert = process.assert = function(x, msg) {

if (!x) throw new Error(msg || 'assertion error');

};

};

startup.processConfig = function() {

// used for `process.config`, but not a real module

var config = NativeModule._source.config;

delete NativeModule._source.config;

// strip the gyp comment line at the beginning

config = config.split('\n')

.slice(1)

.join('\n')

.replace(/"/g, '\\"')

.replace(/'/g, '"');

process.config = JSON.parse(config, function(key, value) {

if (value === 'true') return true;

if (value === 'false') return false;

return value;

});

};

var addPendingUnhandledRejection;

var hasBeenNotifiedProperty = new WeakMap();

startup.processNextTick = function() {

var nextTickQueue = [];

var pendingUnhandledRejections = [];

var microtasksScheduled = false;

// Used to run V8's micro task queue.

var _runMicrotasks = {};

// This tickInfo thing is used so that the C++ code in src/node.cc

// can have easy accesss to our nextTick state, and avoid unnecessary

var tickInfo = {};

// *Must* match Environment::TickInfo::Fields in src/env.h.

var kIndex = 0;

var kLength = 1;

process.nextTick = nextTick;

// Needs to be accessible from beyond this scope.

process._tickCallback = _tickCallback;

process._tickDomainCallback = _tickDomainCallback;

process._setupNextTick(tickInfo, _tickCallback, _runMicrotasks);

_runMicrotasks = _runMicrotasks.runMicrotasks;

function tickDone() {

if (tickInfo[kLength] !== 0) {

if (tickInfo[kLength] <= tickInfo[kIndex]) {

nextTickQueue = [];

tickInfo[kLength] = 0;

} else {

nextTickQueue.splice(0, tickInfo[kIndex]);

tickInfo[kLength] = nextTickQueue.length;

}

}

tickInfo[kIndex] = 0;

}

function scheduleMicrotasks() {

if (microtasksScheduled)

return;

nextTickQueue.push({

callback: runMicrotasksCallback,

domain: null

});

tickInfo[kLength]++;

microtasksScheduled = true;

}

function runMicrotasksCallback() {

microtasksScheduled = false;

_runMicrotasks();

if (tickInfo[kIndex] < tickInfo[kLength] ||

emitPendingUnhandledRejections())

scheduleMicrotasks();

}

// Run callbacks that have no domain.

// Using domains will cause this to be overridden.

function _tickCallback() {

var callback, args, tock;

do {

while (tickInfo[kIndex] < tickInfo[kLength]) {

tock = nextTickQueue[tickInfo[kIndex]++];

callback = tock.callback;

args = tock.args;

// Using separate callback execution functions helps to limit the

// scope of DEOPTs caused by using try blocks and allows direct

// callback invocation with small numbers of arguments to avoid the

// performance hit associated with using `fn.apply()`

if (args === undefined) {

doNTCallback0(callback);

} else {

switch (args.length) {

case 1:

doNTCallback1(callback, args[0]);

break;

case 2:

doNTCallback2(callback, args[0], args[1]);

break;

case 3:

doNTCallback3(callback, args[0], args[1], args[2]);

break;

default:

doNTCallbackMany(callback, args);

}

}

if (1e4 < tickInfo[kIndex])

tickDone();

}

tickDone();

_runMicrotasks();

emitPendingUnhandledRejections();

} while (tickInfo[kLength] !== 0);

}

function _tickDomainCallback() {

var callback, domain, args, tock;

do {

while (tickInfo[kIndex] < tickInfo[kLength]) {

tock = nextTickQueue[tickInfo[kIndex]++];

callback = tock.callback;

domain = tock.domain;

args = tock.args;

if (domain)

domain.enter();

// Using separate callback execution functions helps to limit the

// scope of DEOPTs caused by using try blocks and allows direct

// callback invocation with small numbers of arguments to avoid the

// performance hit associated with using `fn.apply()`

if (args === undefined) {

doNTCallback0(callback);

} else {

switch (args.length) {

case 1:

doNTCallback1(callback, args[0]);

break;

case 2:

doNTCallback2(callback, args[0], args[1]);

break;

case 3:

doNTCallback3(callback, args[0], args[1], args[2]);

break;

default:

doNTCallbackMany(callback, args);

}

}

if (1e4 < tickInfo[kIndex])

tickDone();

if (domain)

domain.exit();

}

tickDone();

_runMicrotasks();

emitPendingUnhandledRejections();

} while (tickInfo[kLength] !== 0);

}

function doNTCallback0(callback) {

var threw = true;

try {

callback();

threw = false;

} finally {

if (threw)

tickDone();

}

}

function doNTCallback1(callback, arg1) {

var threw = true;

try {

callback(arg1);

threw = false;

} finally {

if (threw)

tickDone();

}

}

function doNTCallback2(callback, arg1, arg2) {

var threw = true;

try {

callback(arg1, arg2);

threw = false;

} finally {

if (threw)

tickDone();

}

}

function doNTCallback3(callback, arg1, arg2, arg3) {

var threw = true;

try {

callback(arg1, arg2, arg3);

threw = false;

} finally {

if (threw)

tickDone();

}

}

function doNTCallbackMany(callback, args) {

var threw = true;

try {

callback.apply(null, args);

threw = false;

} finally {

if (threw)

tickDone();

}

}

function TickObject(c, args) {

this.callback = c;

this.domain = process.domain || null;

this.args = args;

}

function nextTick(callback) {

// on the way out, don't bother. it won't get fired anyway.

if (process._exiting)

return;

var args = undefined;

if (arguments.length > 1) {

args = [];

for (var i = 1; i < arguments.length; i++)

args.push(arguments[i]);

}

nextTickQueue.push(new TickObject(callback, args));

tickInfo[kLength]++;

}

function emitPendingUnhandledRejections() {

var hadListeners = false;

while (pendingUnhandledRejections.length > 0) {

var promise = pendingUnhandledRejections.shift();

var reason = pendingUnhandledRejections.shift();

if (hasBeenNotifiedProperty.get(promise) === false) {

hasBeenNotifiedProperty.set(promise, true);

if (!process.emit('unhandledRejection', reason, promise)) {

// Nobody is listening.

// TODO(petkaantonov) Take some default action, see #830

} else

hadListeners = true;

}

}

return hadListeners;

}

addPendingUnhandledRejection = function(promise, reason) {

pendingUnhandledRejections.push(promise, reason);

scheduleMicrotasks();

};

};

startup.processPromises = function() {

var promiseRejectEvent = process._promiseRejectEvent;

function unhandledRejection(promise, reason) {

hasBeenNotifiedProperty.set(promise, false);

addPendingUnhandledRejection(promise, reason);

}

function rejectionHandled(promise) {

var hasBeenNotified = hasBeenNotifiedProperty.get(promise);

if (hasBeenNotified !== undefined) {

hasBeenNotifiedProperty.delete(promise);

if (hasBeenNotified === true)

process.emit('rejectionHandled', promise);

}

}

process._setupPromises(function(event, promise, reason) {

if (event === promiseRejectEvent.unhandled)

unhandledRejection(promise, reason);

else if (event === promiseRejectEvent.handled)

process.nextTick(function() {

rejectionHandled(promise);

});

else

NativeModule.require('assert').fail('unexpected PromiseRejectEvent');

});

};

function evalScript(name) {

var Module = NativeModule.require('module');

var path = NativeModule.require('path');

try {

var cwd = process.cwd();

} catch (e) {

// getcwd(3) can fail if the current working directory has been deleted.

// Fall back to the directory name of the (absolute) executable path.

// It's not really correct but what are the alternatives?

var cwd = path.dirname(process.execPath);

}

var module = new Module(name);

module.filename = path.join(cwd, name);

module.paths = Module._nodeModulePaths(cwd);

var script = process._eval;

var body = script;

script = 'global.__filename = ' + JSON.stringify(name) + ';\n' +

'global.exports = exports;\n' +

'global.module = module;\n' +

'global.__dirname = __dirname;\n' +

'global.require = require;\n' +

'return require("vm").runInThisContext(' +

JSON.stringify(body) + ', { filename: ' +

JSON.stringify(name) + ' });\n';

var result = module._compile(script, name + '-wrapper');

if (process._print_eval) console.log(result);

}

function createWritableStdioStream(fd) {

var stream;

var tty_wrap = process.binding('tty_wrap');

// Note stream._type is used for test-module-load-list.js

switch (tty_wrap.guessHandleType(fd)) {

case 'TTY':

var tty = NativeModule.require('tty');

stream = new tty.WriteStream(fd);

stream._type = 'tty';

// Hack to have stream not keep the event loop alive.

// See https://github.com/joyent/node/issues/1726

if (stream._handle && stream._handle.unref) {

stream._handle.unref();

}

break;

case 'FILE':

var fs = NativeModule.require('fs');

stream = new fs.SyncWriteStream(fd, { autoClose: false });

stream._type = 'fs';

break;

case 'PIPE':

case 'TCP':

var net = NativeModule.require('net');

stream = new net.Socket({

fd: fd,

readable: false,

writable: true

});

// FIXME Should probably have an option in net.Socket to create a

// stream from an existing fd which is writable only. But for now

// we'll just add this hack and set the `readable` member to false.

// Test: ./node test/fixtures/echo.js < /etc/passwd

stream.readable = false;

stream.read = null;

stream._type = 'pipe';

// FIXME Hack to have stream not keep the event loop alive.

// See https://github.com/joyent/node/issues/1726

if (stream._handle && stream._handle.unref) {

stream._handle.unref();

}

break;

default:

// Probably an error on in uv_guess_handle()

throw new Error('Implement me. Unknown stream file type!');

}

// For supporting legacy API we put the FD here.

stream.fd = fd;

stream._isStdio = true;

return stream;

}

startup.processStdio = function() {

var stdin, stdout, stderr;

process.__defineGetter__('stdout', function() {

if (stdout) return stdout;

stdout = createWritableStdioStream(1);

stdout.destroy = stdout.destroySoon = function(er) {

er = er || new Error('process.stdout cannot be closed.');

stdout.emit('error', er);

};

if (stdout.isTTY) {

process.on('SIGWINCH', function() {

stdout._refreshSize();

});

}

return stdout;

});

process.__defineGetter__('stderr', function() {

if (stderr) return stderr;

stderr = createWritableStdioStream(2);

stderr.destroy = stderr.destroySoon = function(er) {

er = er || new Error('process.stderr cannot be closed.');

stderr.emit('error', er);

};

return stderr;

});

process.__defineGetter__('stdin', function() {

if (stdin) return stdin;

var tty_wrap = process.binding('tty_wrap');

var fd = 0;

switch (tty_wrap.guessHandleType(fd)) {

case 'TTY':

var tty = NativeModule.require('tty');

stdin = new tty.ReadStream(fd, {

highWaterMark: 0,

readable: true,

writable: false

});

break;

case 'FILE':

var fs = NativeModule.require('fs');

stdin = new fs.ReadStream(null, { fd: fd, autoClose: false });

break;

case 'PIPE':

case 'TCP':

var net = NativeModule.require('net');

// It could be that process has been started with an IPC channel

// sitting on fd=0, in such case the pipe for this fd is already

// present and creating a new one will lead to the assertion failure

// in libuv.

if (process._channel && process._channel.fd === fd) {

stdin = new net.Socket({

handle: process._channel,

readable: true,

writable: false

});

} else {

stdin = new net.Socket({

fd: fd,

readable: true,

writable: false

});

}

// Make sure the stdin can't be `.end()`-ed

stdin._writableState.ended = true;

break;

default:

// Probably an error on in uv_guess_handle()

throw new Error('Implement me. Unknown stdin file type!');

}

// For supporting legacy API we put the FD here.

stdin.fd = fd;

// stdin starts out life in a paused state, but node doesn't

// know yet. Explicitly to readStop() it to put it in the

// not-reading state.

if (stdin._handle && stdin._handle.readStop) {

stdin._handle.reading = false;

stdin._readableState.reading = false;

stdin._handle.readStop();

}

// if the user calls stdin.pause(), then we need to stop reading

// immediately, so that the process can close down.

stdin.on('pause', function() {

if (!stdin._handle)

return;

stdin._readableState.reading = false;

stdin._handle.reading = false;

stdin._handle.readStop();

});

return stdin;

});

process.openStdin = function() {

process.stdin.resume();

return process.stdin;

};

};

startup.processKillAndExit = function() {

process.exit = function(code) {

if (code || code === 0)

process.exitCode = code;

if (!process._exiting) {

process._exiting = true;

process.emit('exit', process.exitCode || 0);

}

process.reallyExit(process.exitCode || 0);

};

process.kill = function(pid, sig) {

var err;

if (pid != (pid | 0)) {

throw new TypeError('invalid pid');

}

// preserve null signal

if (0 === sig) {

err = process._kill(pid, 0);

} else {

sig = sig || 'SIGTERM';

if (startup.lazyConstants()[sig] &&

sig.slice(0, 3) === 'SIG') {

err = process._kill(pid, startup.lazyConstants()[sig]);

} else {

throw new Error('Unknown signal: ' + sig);

}

}

if (err) {

var errnoException = NativeModule.require('util')._errnoException;

throw errnoException(err, 'kill');

}

return true;

};

};

startup.processSignalHandlers = function() {

// Load events module in order to access prototype elements on process like

// process.addListener.

var signalWraps = {};

function isSignal(event) {

return event.slice(0, 3) === 'SIG' &&

startup.lazyConstants().hasOwnProperty(event);

}

// Detect presence of a listener for the special signal types

process.on('newListener', function(type, listener) {

if (isSignal(type) &&

!signalWraps.hasOwnProperty(type)) {

var Signal = process.binding('signal_wrap').Signal;

var wrap = new Signal();

wrap.unref();

wrap.onsignal = function() { process.emit(type); };

var signum = startup.lazyConstants()[type];

var err = wrap.start(signum);

if (err) {

wrap.close();

var errnoException = NativeModule.require('util')._errnoException;

throw errnoException(err, 'uv_signal_start');

}

signalWraps[type] = wrap;

}

});

process.on('removeListener', function(type, listener) {

if (signalWraps.hasOwnProperty(type) &&

NativeModule.require('events').listenerCount(this, type) === 0) {

signalWraps[type].close();

delete signalWraps[type];

}

});

};

startup.processChannel = function() {

// If we were spawned with env NODE_CHANNEL_FD then load that up and

// start parsing data from that stream.

if (process.env.NODE_CHANNEL_FD) {

var fd = parseInt(process.env.NODE_CHANNEL_FD, 10);

assert(fd >= 0);

// Make sure it's not accidentally inherited by child processes.

delete process.env.NODE_CHANNEL_FD;

var cp = NativeModule.require('child_process');

// Load tcp_wrap to avoid situation where we might immediately receive

// a message.

// FIXME is this really necessary?

process.binding('tcp_wrap');

cp._forkChild(fd);

assert(process.send);

}

};

startup.processRawDebug = function() {

var format = NativeModule.require('util').format;

var rawDebug = process._rawDebug;

process._rawDebug = function() {

rawDebug(format.apply(null, arguments));

};

};

// Below you find a minimal module system, which is used to load the node

// core modules found in lib/*.js. All core modules are compiled into the

// node binary, so they can be loaded faster.

var ContextifyScript = process.binding('contextify').ContextifyScript;

function runInThisContext(code, options) {

var script = new ContextifyScript(code, options);

return script.runInThisContext();

}

function NativeModule(id) {

this.filename = id + '.js';

this.id = id;

this.exports = {};

this.loaded = false;

}

NativeModule._source = process.binding('natives');

NativeModule._cache = {};

NativeModule.require = function(id) {

if (id == 'native_module') {

return NativeModule;

}

var cached = NativeModule.getCached(id);

if (cached) {

return cached.exports;

}

if (!NativeModule.exists(id)) {

throw new Error('No such native module ' + id);

}

process.moduleLoadList.push('NativeModule ' + id);

var nativeModule = new NativeModule(id);

nativeModule.cache();

nativeModule.compile();

return nativeModule.exports;

};

NativeModule.getCached = function(id) {

return NativeModule._cache[id];

};

NativeModule.exists = function(id) {

return NativeModule._source.hasOwnProperty(id);

};

const EXPOSE_INTERNALS = process.execArgv.some(function(arg) {

return arg.match(/^--expose[-_]internals$/);

});

if (EXPOSE_INTERNALS) {

NativeModule.nonInternalExists = NativeModule.exists;

NativeModule.isInternal = function(id) {

return false;

};

} else {

NativeModule.nonInternalExists = function(id) {

return NativeModule.exists(id) && !NativeModule.isInternal(id);

};

NativeModule.isInternal = function(id) {

return id.startsWith('internal/');

};

}

NativeModule.getSource = function(id) {

return NativeModule._source[id];

};

NativeModule.wrap = function(script) {

return NativeModule.wrapper[0] + script + NativeModule.wrapper[1];

};

NativeModule.wrapper = [

'(function (exports, require, module, __filename, __dirname) { ',

'\n});'

];

NativeModule.prototype.compile = function() {

var source = NativeModule.getSource(this.id);

source = NativeModule.wrap(source);

var fn = runInThisContext(source, { filename: this.filename });

fn(this.exports, NativeModule.require, this, this.filename);

this.loaded = true;

};

NativeModule.prototype.cache = function() {

NativeModule._cache[this.id] = this;

};

startup();

});