2021-05-28 17:19:31 +02:00

344 lines
10 KiB
JavaScript

'use strict';
const fs = require('fs');
const vm = require('vm');
const v8 = require('v8');
const path = require('path');
const Module = require('module');
const fork = require('child_process').fork;
v8.setFlagsFromString('--no-lazy');
if (Number.parseInt(process.versions.node, 10) >= 12) {
v8.setFlagsFromString('--no-flush-bytecode'); // Thanks to A-Parser (@a-parser)
}
const COMPILED_EXTNAME = '.jsc';
/**
* Generates v8 bytecode buffer.
* @param {string} javascriptCode JavaScript source that will be compiled to bytecode.
* @returns {Buffer} The generated bytecode.
*/
const compileCode = function (javascriptCode) {
if (typeof javascriptCode !== 'string') {
throw new Error(`javascriptCode must be string. ${typeof javascriptCode} was given.`);
}
const script = new vm.Script(javascriptCode, {
produceCachedData: true
});
const bytecodeBuffer = (script.createCachedData && script.createCachedData.call)
? script.createCachedData()
: script.cachedData;
return bytecodeBuffer;
};
/**
* This function runs the compileCode() function (above)
* via a child process usine Electron as Node
* @param {string} javascriptCode
* @returns {Promise<Buffer>} - returns a Promise which resolves in the generated bytecode.
*/
const compileElectronCode = function (javascriptCode) {
return new Promise((resolve, reject) => {
let data = Buffer.from([]);
const electronPath = path.join('node_modules', 'electron', 'cli.js');
if (!fs.existsSync(electronPath)) {
throw new Error('Electron not installed');
}
const bytenodePath = path.join(__dirname, 'cli.js');
// create a subprocess in which we run Electron as our Node and V8 engine
// running Bytenode to compile our code through stdin/stdout
const proc = fork(electronPath, [bytenodePath, '--compile', '--no-module', '-'], {
env: { ELECTRON_RUN_AS_NODE: '1' },
stdio: ['pipe', 'pipe', 'pipe', 'ipc']
});
if (proc.stdin) {
proc.stdin.write(javascriptCode);
proc.stdin.end();
}
if (proc.stdout) {
proc.stdout.on('data', (chunk) => {
data = Buffer.concat([data, chunk]);
});
proc.stdout.on('error', (err) => {
console.error(err);
});
proc.stdout.on('end', () => {
resolve(data);
});
}
if (proc.stderr) {
proc.stderr.on('data', (chunk) => {
console.error('Error: ', chunk);
});
proc.stderr.on('error', (err) => {
console.error('Error: ', err);
});
}
proc.addListener('message', (message) => console.log(message));
proc.addListener('error', err => console.error(err));
proc.on('error', (err) => reject(err));
proc.on('exit', () => { resolve(data); });
});
};
// TODO: rewrite this function
const fixBytecode = function (bytecodeBuffer) {
if (!Buffer.isBuffer(bytecodeBuffer)) {
throw new Error('bytecodeBuffer must be a buffer object.');
}
const dummyBytecode = compileCode('"ಠ_ಠ"');
if (process.version.startsWith('v8.8') || process.version.startsWith('v8.9')) {
// Node is v8.8.x or v8.9.x
dummyBytecode.slice(16, 20).copy(bytecodeBuffer, 16);
dummyBytecode.slice(20, 24).copy(bytecodeBuffer, 20);
} else if (process.version.startsWith('v12') ||
process.version.startsWith('v13') ||
process.version.startsWith('v14') ||
process.version.startsWith('v15') ||
process.version.startsWith('v16')) {
dummyBytecode.slice(12, 16).copy(bytecodeBuffer, 12);
} else {
dummyBytecode.slice(12, 16).copy(bytecodeBuffer, 12);
dummyBytecode.slice(16, 20).copy(bytecodeBuffer, 16);
}
};
// TODO: rewrite this function
const readSourceHash = function (bytecodeBuffer) {
if (!Buffer.isBuffer(bytecodeBuffer)) {
throw new Error('bytecodeBuffer must be a buffer object.');
}
if (process.version.startsWith('v8.8') || process.version.startsWith('v8.9')) {
// Node is v8.8.x or v8.9.x
// eslint-disable-next-line no-return-assign
return bytecodeBuffer.slice(12, 16).reduce((sum, number, power) => sum += number * Math.pow(256, power), 0);
} else {
// eslint-disable-next-line no-return-assign
return bytecodeBuffer.slice(8, 12).reduce((sum, number, power) => sum += number * Math.pow(256, power), 0);
}
};
/**
* Runs v8 bytecode buffer and returns the result.
* @param {Buffer} bytecodeBuffer The buffer object that was created using compileCode function.
* @returns {any} The result of the very last statement executed in the script.
*/
const runBytecode = function (bytecodeBuffer) {
if (!Buffer.isBuffer(bytecodeBuffer)) {
throw new Error('bytecodeBuffer must be a buffer object.');
}
fixBytecode(bytecodeBuffer);
const length = readSourceHash(bytecodeBuffer);
let dummyCode = '';
if (length > 1) {
dummyCode = '"' + '\u200b'.repeat(length - 2) + '"'; // "\u200b" Zero width space
}
const script = new vm.Script(dummyCode, {
cachedData: bytecodeBuffer
});
if (script.cachedDataRejected) {
throw new Error('Invalid or incompatible cached data (cachedDataRejected)');
}
return script.runInThisContext();
};
/**
* Compiles JavaScript file to .jsc file.
* @param {object|string} args
* @param {string} args.filename The JavaScript source file that will be compiled
* @param {boolean} [args.compileAsModule=true] If true, the output will be a commonjs module
* @param {string} [args.output=filename.jsc] The output filename. Defaults to the same path and name of the original file, but with `.jsc` extension.
* @param {boolean} [args.electron=false] If true, compile code for Electron (which needs to be installed)
* @param {boolean} [args.createLoader=false] If true, create a loader file.
* @param {boolean} [args.loaderFilename='%.loader.js'] Filename or pattern for generated loader files. Defaults to originalFilename.loader.js. Use % as a substitute for originalFilename.
* @param {string} [output] The output filename. (Deprecated: use args.output instead)
* @returns {Promise<string>} A Promise which returns the compiled filename
*/
const compileFile = async function (args, output) {
let filename, compileAsModule, electron, createLoader, loaderFilename;
if (typeof args === 'string') {
filename = args;
compileAsModule = true;
electron = false;
createLoader = false;
} else if (typeof args === 'object') {
filename = args.filename;
compileAsModule = args.compileAsModule !== false;
electron = args.electron;
createLoader = args.createLoader;
loaderFilename = args.loaderFilename;
if (loaderFilename) createLoader = true;
}
if (typeof filename !== 'string') {
throw new Error(`filename must be a string. ${typeof filename} was given.`);
}
// @ts-ignore
const compiledFilename = args.output || output || filename.slice(0, -3) + COMPILED_EXTNAME;
if (typeof compiledFilename !== 'string') {
throw new Error(`output must be a string. ${typeof compiledFilename} was given.`);
}
const javascriptCode = fs.readFileSync(filename, 'utf-8');
let code;
if (compileAsModule) {
code = Module.wrap(javascriptCode.replace(/^#!.*/, ''));
} else {
code = javascriptCode.replace(/^#!.*/, '');
}
let bytecodeBuffer;
if (electron) {
bytecodeBuffer = await compileElectronCode(code);
} else {
bytecodeBuffer = compileCode(code);
}
fs.writeFileSync(compiledFilename, bytecodeBuffer);
if (createLoader) {
addLoaderFile(compiledFilename, loaderFilename);
}
return compiledFilename;
};
/**
* Runs .jsc file and returns the result.
* @param {string} filename
* @returns {any} The result of the very last statement executed in the script.
*/
const runBytecodeFile = function (filename) {
if (typeof filename !== 'string') {
throw new Error(`filename must be a string. ${typeof filename} was given.`);
}
const bytecodeBuffer = fs.readFileSync(filename);
return runBytecode(bytecodeBuffer);
};
Module._extensions[COMPILED_EXTNAME] = function (fileModule, filename) {
const bytecodeBuffer = fs.readFileSync(filename);
fixBytecode(bytecodeBuffer);
const length = readSourceHash(bytecodeBuffer);
let dummyCode = '';
if (length > 1) {
dummyCode = '"' + '\u200b'.repeat(length - 2) + '"'; // "\u200b" Zero width space
}
const script = new vm.Script(dummyCode, {
filename: filename,
lineOffset: 0,
displayErrors: true,
cachedData: bytecodeBuffer
});
if (script.cachedDataRejected) {
throw new Error('Invalid or incompatible cached data (cachedDataRejected)');
}
/*
This part is based on:
https://github.com/zertosh/v8-compile-cache/blob/7182bd0e30ab6f6421365cee0a0c4a8679e9eb7c/v8-compile-cache.js#L158-L178
*/
function require (id) {
return fileModule.require(id);
}
require.resolve = function (request, options) {
// @ts-ignore
return Module._resolveFilename(request, fileModule, false, options);
};
if (process.mainModule) {
require.main = process.mainModule;
}
// @ts-ignore
require.extensions = Module._extensions;
// @ts-ignore
require.cache = Module._cache;
const compiledWrapper = script.runInThisContext({
filename: filename,
lineOffset: 0,
columnOffset: 0,
displayErrors: true
});
const dirname = path.dirname(filename);
const args = [fileModule.exports, require, fileModule, filename, dirname, process, global];
return compiledWrapper.apply(fileModule.exports, args);
};
/**
* Add a loader file for a given .jsc file
* @param {String} fileToLoad path of the .jsc file we're loading
* @param {String} loaderFilename - optional pattern or name of the file to write - defaults to filename.loader.js. Patterns: "%" represents the root name of .jsc file.
*/
const addLoaderFile = function (fileToLoad, loaderFilename) {
let loaderFilePath;
if (typeof loaderFilename === 'boolean' || loaderFilename === undefined || loaderFilename === '') {
loaderFilePath = fileToLoad.replace('.jsc', '.loader.js');
} else {
loaderFilename = loaderFilename.replace('%', path.parse(fileToLoad).name);
loaderFilePath = path.join(path.dirname(fileToLoad), loaderFilename);
}
const relativePath = path.relative(path.dirname(loaderFilePath), fileToLoad);
const code = loaderCode('./' + relativePath);
fs.writeFileSync(loaderFilePath, code);
};
const loaderCode = function (targetPath) {
return `
require('bytenode');
require('${targetPath}');
`;
};
global.bytenode = {
compileCode,
compileFile,
compileElectronCode,
runBytecode,
runBytecodeFile,
addLoaderFile,
loaderCode
};
module.exports = global.bytenode;