Merge "LazyServiceRegistrar: Add flag to prevent shutdown" (0d899f6c) · Commits · e / os / platform_frameworks_native

cmds/servicemanager/ServiceManager.cpp

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -532,6 +532,8 @@ Status ServiceManager::tryUnregisterService(const std::string& name, const sp<IB
	if (clients < 0 \|\| clients > 2) {		if (clients < 0 \|\| clients > 2) {
	// client callbacks are either disabled or there are other clients		// client callbacks are either disabled or there are other clients
	LOG(INFO) << "Tried to unregister " << name << ", but there are clients: " << clients;		LOG(INFO) << "Tried to unregister " << name << ", but there are clients: " << clients;
			// Set this flag to ensure the clients are acknowledged in the next callback
			serviceIt->second.guaranteeClient = true;
	return Status::fromExceptionCode(Status::EX_ILLEGAL_STATE);		return Status::fromExceptionCode(Status::EX_ILLEGAL_STATE);
	}		}

libs/binder/LazyServiceRegistrar.cpp

+31 −5

Original line number	Original line	Diff line number	Diff line
	@@ -31,11 +31,16 @@ using AidlServiceManager = android::os::IServiceManager;

	class ClientCounterCallback : public ::android::os::BnClientCallback {		class ClientCounterCallback : public ::android::os::BnClientCallback {
	public:		public:
	ClientCounterCallback() : mNumConnectedServices(0) {}		ClientCounterCallback() : mNumConnectedServices(0), mForcePersist(false) {}

	bool registerService(const sp<IBinder>& service, const std::string& name,		bool registerService(const sp<IBinder>& service, const std::string& name,
	bool allowIsolated, int dumpFlags);		bool allowIsolated, int dumpFlags);

			/**
			* Set a flag to prevent services from automatically shutting down
			*/
			void forcePersist(bool persist);

	protected:		protected:
	Status onClients(const sp<IBinder>& service, bool clients) override;		Status onClients(const sp<IBinder>& service, bool clients) override;

	@@ -60,6 +65,8 @@ private:
	* Map of registered names and services		* Map of registered names and services
	*/		*/
	std::map<std::string, Service> mRegisteredServices;		std::map<std::string, Service> mRegisteredServices;

			bool mForcePersist;
	};		};

	bool ClientCounterCallback::registerService(const sp<IBinder>& service, const std::string& name,		bool ClientCounterCallback::registerService(const sp<IBinder>& service, const std::string& name,
	@@ -88,6 +95,14 @@ bool ClientCounterCallback::registerService(const sp<IBinder>& service, const st
	return true;		return true;
	}		}

			void ClientCounterCallback::forcePersist(bool persist) {
			mForcePersist = persist;
			if(!mForcePersist) {
			// Attempt a shutdown in case the number of clients hit 0 while the flag was on
			tryShutdown();
			}
			}

	/**		/**
	* onClients is oneway, so no need to worry about multi-threading. Note that this means multiple		* onClients is oneway, so no need to worry about multi-threading. Note that this means multiple
	* invocations could occur on different threads however.		* invocations could occur on different threads however.
	@@ -103,14 +118,21 @@ Status ClientCounterCallback::onClients(const sp<IBinder>& service, bool clients
	mNumConnectedServices, mRegisteredServices.size(),		mNumConnectedServices, mRegisteredServices.size(),
	String8(service->getInterfaceDescriptor()).string(), clients);		String8(service->getInterfaceDescriptor()).string(), clients);

	if (mNumConnectedServices == 0) {
	tryShutdown();		tryShutdown();
	}

	return Status::ok();		return Status::ok();
	}		}

	void ClientCounterCallback::tryShutdown() {		void ClientCounterCallback::tryShutdown() {
			if(mNumConnectedServices > 0) {
			// Should only shut down if there are no clients
			return;
			}

			if(mForcePersist) {
			ALOGI("Shutdown prevented by forcePersist override flag.");
			return;
			}

	ALOGI("Trying to shut down the service. No clients in use for any service in process.");		ALOGI("Trying to shut down the service. No clients in use for any service in process.");

	auto manager = interface_cast<AidlServiceManager>(asBinder(defaultServiceManager()));		auto manager = interface_cast<AidlServiceManager>(asBinder(defaultServiceManager()));
	@@ -165,5 +187,9 @@ status_t LazyServiceRegistrar::registerService(const sp<IBinder>& service, const
	return OK;		return OK;
	}		}

			void LazyServiceRegistrar::forcePersist(bool persist) {
			mClientCC->forcePersist(persist);
			}

	} // namespace hardware		} // namespace hardware
	} // namespace android		} // namespace android
			No newline at end of file

libs/binder/include/binder/LazyServiceRegistrar.h

+6 −0

Original line number	Original line	Diff line number	Diff line
	@@ -34,6 +34,12 @@ class LazyServiceRegistrar {
	const std::string& name = "default",		const std::string& name = "default",
	bool allowIsolated = false,		bool allowIsolated = false,
	int dumpFlags = IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT);		int dumpFlags = IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT);
			/**
			* Force the service to persist, even when it has 0 clients.
			* If setting this flag from the server side, make sure to do so before calling registerService,
			* or there may be a race with the default dynamic shutdown.
			*/
			void forcePersist(bool persist);

	private:		private:
	std::shared_ptr<internal::ClientCounterCallback> mClientCC;		std::shared_ptr<internal::ClientCounterCallback> mClientCC;