lts/lib/child_process.js
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.
'use strict';
const {
ArrayIsArray,
Error,
NumberIsInteger,
ObjectAssign,
ObjectDefineProperty,
ObjectPrototypeHasOwnProperty,
Promise,
} = primordials;
const {
promisify,
convertToValidSignal,
getSystemErrorName
} = require('internal/util');
const { isArrayBufferView } = require('internal/util/types');
const debug = require('internal/util/debuglog').debuglog('child_process');
const { Buffer } = require('buffer');
const { Pipe, constants: PipeConstants } = internalBinding('pipe_wrap');
const {
ERR_INVALID_ARG_VALUE,
ERR_CHILD_PROCESS_IPC_REQUIRED,
ERR_CHILD_PROCESS_STDIO_MAXBUFFER,
ERR_INVALID_ARG_TYPE,
ERR_OUT_OF_RANGE
} = require('internal/errors').codes;
const { clearTimeout, setTimeout } = require('timers');
const { validateString, isInt32 } = require('internal/validators');
const child_process = require('internal/child_process');
const {
getValidStdio,
setupChannel,
ChildProcess,
stdioStringToArray
} = child_process;
const MAX_BUFFER = 1024 * 1024;
function fork(modulePath /* , args, options */) {
validateString(modulePath, 'modulePath');
// Get options and args arguments.
let execArgv;
let options = {};
let args = [];
let pos = 1;
if (pos < arguments.length && ArrayIsArray(arguments[pos])) {
args = arguments[pos++];
}
if (pos < arguments.length &&
(arguments[pos] === undefined || arguments[pos] === null)) {
pos++;
}
if (pos < arguments.length && arguments[pos] != null) {
if (typeof arguments[pos] !== 'object') {
throw new ERR_INVALID_ARG_VALUE(`arguments[${pos}]`, arguments[pos]);
}
options = { ...arguments[pos++] };
}
// Prepare arguments for fork:
execArgv = options.execArgv || process.execArgv;
if (execArgv === process.execArgv && process._eval != null) {
const index = execArgv.lastIndexOf(process._eval);
if (index > 0) {
// Remove the -e switch to avoid fork bombing ourselves.
execArgv = execArgv.slice();
execArgv.splice(index - 1, 2);
}
}
args = execArgv.concat([modulePath], args);
if (typeof options.stdio === 'string') {
options.stdio = stdioStringToArray(options.stdio, 'ipc');
} else if (!ArrayIsArray(options.stdio)) {
// Use a separate fd=3 for the IPC channel. Inherit stdin, stdout,
// and stderr from the parent if silent isn't set.
options.stdio = stdioStringToArray(
options.silent ? 'pipe' : 'inherit',
'ipc');
} else if (!options.stdio.includes('ipc')) {
throw new ERR_CHILD_PROCESS_IPC_REQUIRED('options.stdio');
}
options.execPath = options.execPath || process.execPath;
options.shell = false;
return spawn(options.execPath, args, options);
}
function _forkChild(fd, serializationMode) {
// set process.send()
const p = new Pipe(PipeConstants.IPC);
p.open(fd);
p.unref();
const control = setupChannel(process, p, serializationMode);
process.on('newListener', function onNewListener(name) {
if (name === 'message' || name === 'disconnect') control.ref();
});
process.on('removeListener', function onRemoveListener(name) {
if (name === 'message' || name === 'disconnect') control.unref();
});
}
function normalizeExecArgs(command, options, callback) {
if (typeof options === 'function') {
callback = options;
options = undefined;
}
// Make a shallow copy so we don't clobber the user's options object.
options = { ...options };
options.shell = typeof options.shell === 'string' ? options.shell : true;
return {
file: command,
options: options,
callback: callback
};
}
function exec(command, options, callback) {
const opts = normalizeExecArgs(command, options, callback);
return module.exports.execFile(opts.file,
opts.options,
opts.callback);
}
const customPromiseExecFunction = (orig) => {
return (...args) => {
let resolve;
let reject;
const promise = new Promise((res, rej) => {
resolve = res;
reject = rej;
});
promise.child = orig(...args, (err, stdout, stderr) => {
if (err !== null) {
err.stdout = stdout;
err.stderr = stderr;
reject(err);
} else {
resolve({ stdout, stderr });
}
});
return promise;
};
};
ObjectDefineProperty(exec, promisify.custom, {
enumerable: false,
value: customPromiseExecFunction(exec)
});
function execFile(file /* , args, options, callback */) {
let args = [];
let callback;
let options;
// Parse the optional positional parameters.
let pos = 1;
if (pos < arguments.length && ArrayIsArray(arguments[pos])) {
args = arguments[pos++];
} else if (pos < arguments.length && arguments[pos] == null) {
pos++;
}
if (pos < arguments.length && typeof arguments[pos] === 'object') {
options = arguments[pos++];
} else if (pos < arguments.length && arguments[pos] == null) {
pos++;
}
if (pos < arguments.length && typeof arguments[pos] === 'function') {
callback = arguments[pos++];
}
if (!callback && pos < arguments.length && arguments[pos] != null) {
throw new ERR_INVALID_ARG_VALUE('args', arguments[pos]);
}
options = {
encoding: 'utf8',
timeout: 0,
maxBuffer: MAX_BUFFER,
killSignal: 'SIGTERM',
cwd: null,
env: null,
shell: false,
...options
};
// Validate the timeout, if present.
validateTimeout(options.timeout);
// Validate maxBuffer, if present.
validateMaxBuffer(options.maxBuffer);
options.killSignal = sanitizeKillSignal(options.killSignal);
const child = spawn(file, args, {
cwd: options.cwd,
env: options.env,
gid: options.gid,
uid: options.uid,
shell: options.shell,
windowsHide: !!options.windowsHide,
windowsVerbatimArguments: !!options.windowsVerbatimArguments
});
let encoding;
const _stdout = [];
const _stderr = [];
if (options.encoding !== 'buffer' && Buffer.isEncoding(options.encoding)) {
encoding = options.encoding;
} else {
encoding = null;
}
let stdoutLen = 0;
let stderrLen = 0;
let killed = false;
let exited = false;
let timeoutId;
let ex = null;
let cmd = file;
function exithandler(code, signal) {
if (exited) return;
exited = true;
if (timeoutId) {
clearTimeout(timeoutId);
timeoutId = null;
}
if (!callback) return;
// merge chunks
let stdout;
let stderr;
if (encoding ||
(
child.stdout &&
child.stdout.readableEncoding
)) {
stdout = _stdout.join('');
} else {
stdout = Buffer.concat(_stdout);
}
if (encoding ||
(
child.stderr &&
child.stderr.readableEncoding
)) {
stderr = _stderr.join('');
} else {
stderr = Buffer.concat(_stderr);
}
if (!ex && code === 0 && signal === null) {
callback(null, stdout, stderr);
return;
}
if (args.length !== 0)
cmd += ` ${args.join(' ')}`;
if (!ex) {
// eslint-disable-next-line no-restricted-syntax
ex = new Error('Command failed: ' + cmd + '\n' + stderr);
ex.killed = child.killed || killed;
ex.code = code < 0 ? getSystemErrorName(code) : code;
ex.signal = signal;
}
ex.cmd = cmd;
callback(ex, stdout, stderr);
}
function errorhandler(e) {
ex = e;
if (child.stdout)
child.stdout.destroy();
if (child.stderr)
child.stderr.destroy();
exithandler();
}
function kill() {
if (child.stdout)
child.stdout.destroy();
if (child.stderr)
child.stderr.destroy();
killed = true;
try {
child.kill(options.killSignal);
} catch (e) {
ex = e;
exithandler();
}
}
if (options.timeout > 0) {
timeoutId = setTimeout(function delayedKill() {
kill();
timeoutId = null;
}, options.timeout);
}
if (child.stdout) {
if (encoding)
child.stdout.setEncoding(encoding);
child.stdout.on('data', function onChildStdout(chunk) {
const encoding = child.stdout.readableEncoding;
const length = encoding ?
Buffer.byteLength(chunk, encoding) :
chunk.length;
stdoutLen += length;
if (stdoutLen > options.maxBuffer) {
const truncatedLen = options.maxBuffer - (stdoutLen - length);
_stdout.push(chunk.slice(0, truncatedLen));
ex = new ERR_CHILD_PROCESS_STDIO_MAXBUFFER('stdout');
kill();
} else {
_stdout.push(chunk);
}
});
}
if (child.stderr) {
if (encoding)
child.stderr.setEncoding(encoding);
child.stderr.on('data', function onChildStderr(chunk) {
const encoding = child.stderr.readableEncoding;
const length = encoding ?
Buffer.byteLength(chunk, encoding) :
chunk.length;
stderrLen += length;
if (stderrLen > options.maxBuffer) {
const truncatedLen = options.maxBuffer - (stderrLen - length);
_stderr.push(chunk.slice(0, truncatedLen));
ex = new ERR_CHILD_PROCESS_STDIO_MAXBUFFER('stderr');
kill();
} else {
_stderr.push(chunk);
}
});
}
child.addListener('close', exithandler);
child.addListener('error', errorhandler);
return child;
}
ObjectDefineProperty(execFile, promisify.custom, {
enumerable: false,
value: customPromiseExecFunction(execFile)
});
function normalizeSpawnArguments(file, args, options) {
validateString(file, 'file');
if (file.length === 0)
throw new ERR_INVALID_ARG_VALUE('file', file, 'cannot be empty');
if (ArrayIsArray(args)) {
args = args.slice(0);
} else if (args == null) {
args = [];
} else if (typeof args !== 'object') {
throw new ERR_INVALID_ARG_TYPE('args', 'object', args);
} else {
options = args;
args = [];
}
if (options === undefined)
options = {};
else if (options === null || typeof options !== 'object')
throw new ERR_INVALID_ARG_TYPE('options', 'object', options);
// Validate the cwd, if present.
if (options.cwd != null &&
typeof options.cwd !== 'string') {
throw new ERR_INVALID_ARG_TYPE('options.cwd', 'string', options.cwd);
}
// Validate detached, if present.
if (options.detached != null &&
typeof options.detached !== 'boolean') {
throw new ERR_INVALID_ARG_TYPE('options.detached',
'boolean', options.detached);
}
// Validate the uid, if present.
if (options.uid != null && !isInt32(options.uid)) {
throw new ERR_INVALID_ARG_TYPE('options.uid', 'int32', options.uid);
}
// Validate the gid, if present.
if (options.gid != null && !isInt32(options.gid)) {
throw new ERR_INVALID_ARG_TYPE('options.gid', 'int32', options.gid);
}
// Validate the shell, if present.
if (options.shell != null &&
typeof options.shell !== 'boolean' &&
typeof options.shell !== 'string') {
throw new ERR_INVALID_ARG_TYPE('options.shell',
['boolean', 'string'], options.shell);
}
// Validate argv0, if present.
if (options.argv0 != null &&
typeof options.argv0 !== 'string') {
throw new ERR_INVALID_ARG_TYPE('options.argv0', 'string', options.argv0);
}
// Validate windowsHide, if present.
if (options.windowsHide != null &&
typeof options.windowsHide !== 'boolean') {
throw new ERR_INVALID_ARG_TYPE('options.windowsHide',
'boolean', options.windowsHide);
}
// Validate windowsVerbatimArguments, if present.
if (options.windowsVerbatimArguments != null &&
typeof options.windowsVerbatimArguments !== 'boolean') {
throw new ERR_INVALID_ARG_TYPE('options.windowsVerbatimArguments',
'boolean',
options.windowsVerbatimArguments);
}
// Make a shallow copy so we don't clobber the user's options object.
options = { ...options };
if (options.shell) {
const command = [file].concat(args).join(' ');
// Set the shell, switches, and commands.
if (process.platform === 'win32') {
if (typeof options.shell === 'string')
file = options.shell;
else
file = process.env.comspec || 'cmd.exe';
// '/d /s /c' is used only for cmd.exe.
if (/^(?:.*\\)?cmd(?:\.exe)?$/i.test(file)) {
args = ['/d', '/s', '/c', `"${command}"`];
options.windowsVerbatimArguments = true;
} else {
args = ['-c', command];
}
} else {
if (typeof options.shell === 'string')
file = options.shell;
else if (process.platform === 'android')
file = '/system/bin/sh';
else
file = '/bin/sh';
args = ['-c', command];
}
}
if (typeof options.argv0 === 'string') {
args.unshift(options.argv0);
} else {
args.unshift(file);
}
const env = options.env || process.env;
const envPairs = [];
// process.env.NODE_V8_COVERAGE always propagates, making it possible to
// collect coverage for programs that spawn with white-listed environment.
if (process.env.NODE_V8_COVERAGE &&
!ObjectPrototypeHasOwnProperty(options.env || {}, 'NODE_V8_COVERAGE')) {
env.NODE_V8_COVERAGE = process.env.NODE_V8_COVERAGE;
}
// Prototype values are intentionally included.
for (const key in env) {
const value = env[key];
if (value !== undefined) {
envPairs.push(`${key}=${value}`);
}
}
return {
file: file,
args: args,
options: options,
envPairs: envPairs
};
}
function spawn(file, args, options) {
const opts = normalizeSpawnArguments(file, args, options);
const child = new ChildProcess();
options = opts.options;
debug('spawn', opts.args, options);
child.spawn({
file: opts.file,
args: opts.args,
cwd: options.cwd,
windowsHide: !!options.windowsHide,
windowsVerbatimArguments: !!options.windowsVerbatimArguments,
detached: !!options.detached,
envPairs: opts.envPairs,
stdio: options.stdio,
uid: options.uid,
gid: options.gid,
serialization: options.serialization,
});
return child;
}
function spawnSync(file, args, options) {
const opts = normalizeSpawnArguments(file, args, options);
const defaults = {
maxBuffer: MAX_BUFFER,
...opts.options
};
options = opts.options = defaults;
debug('spawnSync', opts.args, options);
// Validate the timeout, if present.
validateTimeout(options.timeout);
// Validate maxBuffer, if present.
validateMaxBuffer(options.maxBuffer);
options.file = opts.file;
options.args = opts.args;
options.envPairs = opts.envPairs;
// Validate and translate the kill signal, if present.
options.killSignal = sanitizeKillSignal(options.killSignal);
options.stdio = getValidStdio(options.stdio || 'pipe', true).stdio;
if (options.input) {
const stdin = options.stdio[0] = { ...options.stdio[0] };
stdin.input = options.input;
}
// We may want to pass data in on any given fd, ensure it is a valid buffer
for (let i = 0; i < options.stdio.length; i++) {
const input = options.stdio[i] && options.stdio[i].input;
if (input != null) {
const pipe = options.stdio[i] = { ...options.stdio[i] };
if (isArrayBufferView(input)) {
pipe.input = input;
} else if (typeof input === 'string') {
pipe.input = Buffer.from(input, options.encoding);
} else {
throw new ERR_INVALID_ARG_TYPE(`options.stdio[${i}]`,
['Buffer',
'TypedArray',
'DataView',
'string'],
input);
}
}
}
return child_process.spawnSync(opts);
}
function checkExecSyncError(ret, args, cmd) {
let err;
if (ret.error) {
err = ret.error;
} else if (ret.status !== 0) {
let msg = 'Command failed: ';
msg += cmd || args.join(' ');
if (ret.stderr && ret.stderr.length > 0)
msg += `\n${ret.stderr.toString()}`;
// eslint-disable-next-line no-restricted-syntax
err = new Error(msg);
}
if (err) {
ObjectAssign(err, ret);
}
return err;
}
function execFileSync(command, args, options) {
const opts = normalizeSpawnArguments(command, args, options);
const inheritStderr = !opts.options.stdio;
const ret = spawnSync(opts.file, opts.args.slice(1), opts.options);
if (inheritStderr && ret.stderr)
process.stderr.write(ret.stderr);
const err = checkExecSyncError(ret, opts.args, undefined);
if (err)
throw err;
return ret.stdout;
}
function execSync(command, options) {
const opts = normalizeExecArgs(command, options, null);
const inheritStderr = !opts.options.stdio;
const ret = spawnSync(opts.file, opts.options);
if (inheritStderr && ret.stderr)
process.stderr.write(ret.stderr);
const err = checkExecSyncError(ret, opts.args, command);
if (err)
throw err;
return ret.stdout;
}
function validateTimeout(timeout) {
if (timeout != null && !(NumberIsInteger(timeout) && timeout >= 0)) {
throw new ERR_OUT_OF_RANGE('timeout', 'an unsigned integer', timeout);
}
}
function validateMaxBuffer(maxBuffer) {
if (maxBuffer != null && !(typeof maxBuffer === 'number' && maxBuffer >= 0)) {
throw new ERR_OUT_OF_RANGE('options.maxBuffer',
'a positive number',
maxBuffer);
}
}
function sanitizeKillSignal(killSignal) {
if (typeof killSignal === 'string' || typeof killSignal === 'number') {
return convertToValidSignal(killSignal);
} else if (killSignal != null) {
throw new ERR_INVALID_ARG_TYPE('options.killSignal',
['string', 'number'],
killSignal);
}
}
module.exports = {
_forkChild,
ChildProcess,
exec,
execFile,
execFileSync,
execSync,
fork,
spawn,
spawnSync
};