UdrCppEngine.h

FB_BOOLEAN* FB_UDR_PLUGIN_ENTRY_POINT(::Firebird::IStatus* status, FB_BOOLEAN* theirUnloadFlag, ::Firebird::IUdrPlugin* udrPlugin);

UdrCppEngine.h

	extern "C" FB_DLL_EXPORT FB_BOOLEAN* FB_UDR_PLUGIN_ENTRY_POINT(::Firebird::IStatus* status,	\
		FB_BOOLEAN* theirUnloadFlag, ::Firebird::IUdrPlugin* udrPlugin)	\
	{	\
		::Firebird::Udr::FactoryRegistration::finish(status, udrPlugin);	\
		\
		class UnloadDetector	\
		{	\
		public:	\
			UnloadDetector(FB_BOOLEAN* aTheirUnloadFlag, ::Firebird::IUdrPlugin* aUdrPlugin)	\
				: myUnloadFlag(FB_FALSE),	\
				  theirUnloadFlag(aTheirUnloadFlag),	\
				  udrPlugin(aUdrPlugin)	\
			{	\
			}	\
			\
			~UnloadDetector()	\
			{	\
				if (!myUnloadFlag)	\
					*theirUnloadFlag = FB_TRUE;	\
			}	\
		\
			FB_BOOLEAN myUnloadFlag;	\
			FB_BOOLEAN* theirUnloadFlag;	\
			::Firebird::IUdrPlugin* udrPlugin;	\
		};	\
		\
		static UnloadDetector unloadDetector(theirUnloadFlag, udrPlugin);	\
		\
		return &unloadDetector.myUnloadFlag;	\
	}

UdrEngine.cpp

UdrPluginImpl* Engine::loadModule(ThrowStatusWrapper* status, IRoutineMetadata* metadata, PathName* moduleName, string* entryPoint)
{
...
		UdrPluginImpl* udrPlugin = FB_NEW UdrPluginImpl(*moduleName, module);
		udrPlugin->theirUnloadFlag = entryPoint(status, &udrPlugin->myUnloadFlag, udrPlugin);
...
...
}

class UdrPluginImpl : public VersionedIface<IUdrPluginImpl<UdrPluginImpl, ThrowStatusWrapper> >
{
public:
	UdrPluginImpl(const PathName& aModuleName, ModuleLoader::Module* aModule)
		: moduleName(*getDefaultMemoryPool(), aModuleName),
		  module(aModule),
		  myUnloadFlag(FB_FALSE),
		  theirUnloadFlag(NULL),
		  functionsMap(*getDefaultMemoryPool()),
		  proceduresMap(*getDefaultMemoryPool()),
		  triggersMap(*getDefaultMemoryPool())
	{
	}

	~UdrPluginImpl()
	{
		if (myUnloadFlag)
			return;

		*theirUnloadFlag = FB_TRUE;

		{
			GenericMap<Pair<Left<string, IUdrFunctionFactory*> > >::Accessor accessor(&functionsMap);
			for (bool cont = accessor.getFirst(); cont; cont = accessor.getNext())
				accessor.current()->second->dispose();
		}

		{
			GenericMap<Pair<Left<string, IUdrProcedureFactory*> > >::Accessor accessor(&proceduresMap);
			for (bool cont = accessor.getFirst(); cont; cont = accessor.getNext())
				accessor.current()->second->dispose();
		}

		{
			GenericMap<Pair<Left<string, IUdrTriggerFactory*> > >::Accessor accessor(&triggersMap);
			for (bool cont = accessor.getFirst(); cont; cont = accessor.getNext())
				accessor.current()->second->dispose();
		}
	}

	FB_BOOLEAN  myUnloadFlag;
	FB_BOOLEAN* theirUnloadFlag;
};