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#include "win32/tip/tip_dll_module.h"

#include <windows.h>

#include "absl/base/call_once.h"
#include "base/crash_report_handler.h"

namespace mozc::win32::tsf {
namespace {

void TipShutdownCrashReportHandler() {
  if (CrashReportHandler::IsInitialized()) {
    // Uninitialize the breakpad.
    CrashReportHandler::Uninitialize();
  }
}

}  // namespace

HMODULE TipDllModule::module_handle_ = nullptr;
bool TipDllModule::unloaded_ = false;
absl::once_flag TipDllModule::uninitialize_once_;

void TipComTraits::OnObjectRelease(ULONG ref) {
  if (ref == 0) {
    TipDllModule::PrepareForShutdown();
  }
}

void TipDllModule::PrepareForShutdown() {
  // All COM objects are now released, so our DLL is likely to be unloaded soon.
  // Here is the good point to release global resources that should not be
  // unloaded in DllMain due to the loader lock. However, it should also be
  // noted that there is a chance that AddRef() is called again and the
  // application continues to use Mozc client DLL. Actually we can observe this
  // situation inside "Visual Studio 2012 Remote Debugging Monitor" running on
  // Windows 8. Thus we must not shut down libraries that cannot be designed to
  // be re-initializable. For instance, we must not call following functions
  // here.
  // - mozc::FinalizeSingletons()                - b/10233768
  // - mozc::protobuf::ShutdownProtobufLibrary() - b/2126375
  absl::call_once(uninitialize_once_, &TipShutdownCrashReportHandler);
}

void TipDllModule::InitForUnitTest() {
  absl::call_once(uninitialize_once_, []() {});
}

}  // namespace mozc::win32::tsf
