1 - Bus Name Discovery.js

const { getData, setData, runAsPkg } = require('./common');

const { join } = require('path'),
      { readFileSync, statSync, readdirSync } = require('fs');

function getNamesFromRootfs(parentPath, result = []) {
  console.log(`getNamesFromRootfs: parent: ${parentPath}`);

  readdirSync(parentPath).forEach(child => {
    const childPath = join(parentPath, child),
          stat = statSync(childPath);

    if (stat.isDirectory()) {
      getNamesFromRootfs(childPath, result); // Recursive!
      return;
    }

    if (!stat.isFile()) {
      return;
    }

    console.log(`getNamesFromRootfs: child: ${childPath}`);

    const content = readFileSync(childPath, {encoding: 'utf-8'});
    if (!/\[D-BUS Service\]/i.test(content)) {
      return;
    }

    const [_, name] = content.match(/Name\s*=\s*([^\s]+)$/im) || [];
    if (name === undefined) {
      return;
    }

    result.push(name);
  });

  return result;
}

async function getNamesFromTarget(runner) {
  const result = await runner('dbus-send --system --dest=org.freedesktop.DBus --type=method_call --print-reply /org/freedesktop/DBus org.freedesktop.DBus.ListNames');
  return result.match(/string "[^"]+"/g).map(v => v.split('"')[1]);
}

function deduplicate(result = []) {
  const dict = {};
  result.forEach(v => dict[v] = true);
  return Object.keys(dict);
}

async function main() {
  // Check if dbusPath is readable
  const dbusPath = getData('dbusPath');
  try {
    readdirSync(dbusPath);
  } catch (e) {
    throw new Error(`Place the extracted D-Bus service files at "${dbusPath}". This value can be changed in db.json.`);
  }

  const names = [
                  // Recursively grab the names from D-Bus service files
                  ...(getNamesFromRootfs(dbusPath)), 

                  // Grab the names of the running bus names
                  ...(await getNamesFromTarget(runAsPkg)) 
                ]; 

  // Save names
  setData('names', deduplicate(names));
}

main();