chuanqi/996box-decompiled/jsc-extract/probe-header.js

// 生成当前 V8 的 dummy 字节码,对比 996box .jsc 头部
const vm = require('vm');
const v8 = require('v8');

v8.setFlagsFromString('--no-lazy');
v8.setFlagsFromString('--no-flush-bytecode');

const script = new vm.Script('"\u200b"', { produceCachedData: true });
const cached = script.cachedData;
console.log('Current V8 version:', process.versions.v8);
console.log('Dummy cachedData size:', cached.length);
console.log('Dummy header (first 32 bytes):', cached.subarray(0, 32).toString('hex'));

console.log('\n996box urlCreator.jsc:');
const raw = require('fs').readFileSync(process.argv[2]);
console.log('  header:', raw.subarray(0, 32).toString('hex'));

// 字段对比
function fields(buf, off) {
  return {
    magic: buf.subarray(off+0, off+2).toString('hex'),
    versionHash: '0x' + buf.readUInt32LE(off+4).toString(16),
    sourceHash: '0x' + buf.readUInt32LE(off+8).toString(16),
    flagHash: '0x' + buf.readUInt32LE(off+12).toString(16),
    roChecksum: '0x' + buf.readUInt32LE(off+16).toString(16),
    payloadLen: '0x' + buf.readUInt32LE(off+20).toString(16),
    checksum: '0x' + buf.readUInt32LE(off+24).toString(16),
  };
}

console.log('\nDummy:', fields(cached, 0));
console.log('996box (off 0, bytenode wrapper included):', fields(raw, 0));
console.log('996box (off 2, bytenode wrapper stripped):', fields(raw, 2));