Function execSync

src/exec.js:20–134

(cmd, opts, pipe)

// We use this function to run `exec` synchronously while also providing realtime
// output.
function execSync(cmd, opts, pipe) {
  if (!common.config.execPath) {
    try {
        common.error('Unable to find a path to the node binary. Please manually set config.execPath');
    } catch (e) {
      if (opts.fatal) {
        throw e;
      }

      return;
    }
  }

  var tempDir = _tempDir();
  var paramsFile = path.join(tempDir, common.randomFileName());
  var stderrFile = path.join(tempDir, common.randomFileName());
  var stdoutFile = path.join(tempDir, common.randomFileName());

  opts = common.extend({
    silent: common.config.silent,
    fatal: common.config.fatal, // TODO(nfischer): this and the line above are probably unnecessary
    cwd: _pwd().toString(),
    env: process.env,
    maxBuffer: DEFAULT_MAXBUFFER_SIZE,
    encoding: 'utf8',
  }, opts);

  if (fs.existsSync(paramsFile)) common.unlinkSync(paramsFile);
  if (fs.existsSync(stderrFile)) common.unlinkSync(stderrFile);
  if (fs.existsSync(stdoutFile)) common.unlinkSync(stdoutFile);

  opts.cwd = path.resolve(opts.cwd);

  var paramsToSerialize = {
    command: cmd,
    execOptions: opts,
    pipe,
    stdoutFile,
    stderrFile,
  };

  // Create the files and ensure these are locked down (for read and write) to
  // the current user. The main concerns here are:
  //
  // * If we execute a command which prints sensitive output, then
  //   stdoutFile/stderrFile must not be readable by other users.
  // * paramsFile must not be readable by other users, or else they can read it
  //   to figure out the path for stdoutFile/stderrFile and create these first
  //   (locked down to their own access), which will crash exec() when it tries
  //   to write to the files.
  function writeFileLockedDown(filePath, data) {
    fs.writeFileSync(filePath, data, {
      encoding: 'utf8',
      mode: parseInt('600', 8),
    });
  }
  writeFileLockedDown(stdoutFile, '');
  writeFileLockedDown(stderrFile, '');