Method ThreadSafeLazyInit

tests/gtest/gtest-all.cc:10121–10165

Initializes owner_thread_id_ and critical_section_ in static mutexes.

// Initializes owner_thread_id_ and critical_section_ in static mutexes.
void Mutex::ThreadSafeLazyInit() {
  // Dynamic mutexes are initialized in the constructor.
  if (type_ == kStatic) {
    switch (
        ::InterlockedCompareExchange(&critical_section_init_phase_, 1L, 0L)) {
      case 0:
        // If critical_section_init_phase_ was 0 before the exchange, we
        // are the first to test it and need to perform the initialization.
        owner_thread_id_ = 0;
        {
          // Use RAII to flag that following mem alloc is never deallocated.
#ifdef _MSC_VER
          MemoryIsNotDeallocated memory_is_not_deallocated;
#endif  // _MSC_VER
          critical_section_ = new CRITICAL_SECTION;
        }
        ::InitializeCriticalSection(critical_section_);
        // Updates the critical_section_init_phase_ to 2 to signal
        // initialization complete.
        GTEST_CHECK_(::InterlockedCompareExchange(
                          &critical_section_init_phase_, 2L, 1L) ==
                      1L);
        break;
      case 1:
        // Somebody else is already initializing the mutex; spin until they
        // are done.
        while (::InterlockedCompareExchange(&critical_section_init_phase_,
                                            2L,
                                            2L) != 2L) {
          // Possibly yields the rest of the thread's time slice to other
          // threads.
          ::Sleep(0);
        }
        break;

      case 2:
        break;  // The mutex is already initialized and ready for use.

      default:
        GTEST_CHECK_(false)
            << "Unexpected value of critical_section_init_phase_ "
            << "while initializing a static mutex.";
    }
  }
}

namespace {