launchfx.cpp

#define UNICODE
#define _UNICODE
#define _WIN32_WINNT 0x0A00

#include <windows.h>

#include <iostream>
#include <memory>
#include <string>
#include <sstream>
#include <string.h>

using namespace std;

static wstring
BuildCommandLine(int argc, wchar_t* argv[])
{
  // Just quote everything
  wostringstream oss;
  for (int i = 1; i < argc; ++i) {
    oss << L"\"" << argv[i] << L"\" ";
  }
  return oss.str();
}

int wmain(int argc, wchar_t* argv[])
{
  if (argc < 2) {
    wcout << L"Usage: " << argv[0] << " <path_to_firefox_binary> [firefox_command_line_options]" << endl;
    return 1;
  }
  wchar_t *exe = argv[1];
  const wstring& cls = BuildCommandLine(argc, argv);
  auto cl = make_unique<wchar_t[]>(cls.size() + 1);
  wcscpy(cl.get(), cls.c_str());
  wcout << L"Using command line: " << cl.get() << endl;

  STARTUPINFOEXW siex;
  ZeroMemory(&siex, sizeof(siex));
  siex.StartupInfo.cb = sizeof(STARTUPINFOEXW);
  SIZE_T listSize = 0;
  DWORD err;
  if (!InitializeProcThreadAttributeList(nullptr, 1, 0, &listSize) && (err = GetLastError()) != ERROR_INSUFFICIENT_BUFFER) {
    cout << "InitializeProcThreadAttributeList failed with code " << err << endl;
    return 1;
  }
  auto listBytes = make_unique<char[]>(listSize);
  LPPROC_THREAD_ATTRIBUTE_LIST list = reinterpret_cast<LPPROC_THREAD_ATTRIBUTE_LIST>(listBytes.get());
  if (!InitializeProcThreadAttributeList(list, 1, 0, &listSize)) {
    cout << "InitializeProcThreadAttributeList (2) failed" << endl;
    return 1;
  }
  DWORD64 policy = PROCESS_CREATION_MITIGATION_POLICY_BLOCK_NON_MICROSOFT_BINARIES_ALWAYS_ON;
  if (!UpdateProcThreadAttribute(list, 0, PROC_THREAD_ATTRIBUTE_MITIGATION_POLICY, &policy, sizeof(policy), nullptr, nullptr)) {
    cout << "UpdateProcThreadAttribute failed" << endl;
    return 1;
  }
  siex.lpAttributeList = list;

  PROCESS_INFORMATION pi = {0};
  BOOL ok = CreateProcessW(exe, cl.get(), nullptr, nullptr, FALSE, EXTENDED_STARTUPINFO_PRESENT, nullptr, nullptr, &siex.StartupInfo, &pi);
  err = GetLastError();

  DeleteProcThreadAttributeList(list);

  if (!ok) {
    cout << "CreateProcess failed with error code " << err << endl;
    return 1;
  }
  cout << "Created PID " << pi.dwProcessId << endl;
  CloseHandle(pi.hProcess);
  CloseHandle(pi.hThread);
  return 0;
}