Merge "RpcSession attaches/detaches JVM for Java thread" am: 487109e7bb (c0c11cbb) · Commits · e / os / android_frameworks_native

libs/binder/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -192,6 +192,7 @@ cc_library {

		header_libs: [
		"libbinder_headers",
		"libandroid_runtime_threads_headers",
		],

		export_header_lib_headers: [

libs/binder/RpcSession.cpp

+46 −0

Original line number	Diff line number	Diff line
		@@ -18,13 +18,16 @@

		#include <binder/RpcSession.h>

		#include <dlfcn.h>
		#include <inttypes.h>
		#include <poll.h>
		#include <pthread.h>
		#include <unistd.h>

		#include <string_view>

		#include <android-base/macros.h>
		#include <android_runtime/threads.h>
		#include <binder/Parcel.h>
		#include <binder/RpcServer.h>
		#include <binder/Stability.h>
		@@ -274,10 +277,53 @@ RpcSession::PreJoinSetupResult RpcSession::preJoinSetup(base::unique_fd fd) {
		};
		}

		namespace {
		// RAII object for attaching / detaching current thread to JVM if Android Runtime exists. If
		// Android Runtime doesn't exist, no-op.
		class JavaThreadAttacher {
		public:
		JavaThreadAttacher() {
		// Use dlsym to find androidJavaAttachThread because libandroid_runtime is loaded after
		// libbinder.
		static auto attachFn = reinterpret_cast<decltype(&androidJavaAttachThread)>(
		dlsym(RTLD_DEFAULT, "androidJavaAttachThread"));
		if (attachFn == nullptr) return;

		char buf[16];
		const char* threadName = "UnknownRpcSessionThread"; // default thread name
		if (0 == pthread_getname_np(pthread_self(), buf, sizeof(buf))) {
		threadName = buf;
		}
		LOG_RPC_DETAIL("Attaching current thread %s to JVM", threadName);
		LOG_ALWAYS_FATAL_IF(!attachFn(threadName), "Cannot attach thread %s to JVM", threadName);
		mAttached = true;
		}
		~JavaThreadAttacher() {
		if (!mAttached) return;
		static auto detachFn = reinterpret_cast<decltype(&androidJavaDetachThread)>(
		dlsym(RTLD_DEFAULT, "androidJavaDetachThread"));
		LOG_ALWAYS_FATAL_IF(detachFn == nullptr,
		"androidJavaAttachThread exists but androidJavaDetachThread doesn't");

		LOG_RPC_DETAIL("Detaching current thread from JVM");
		if (detachFn()) {
		mAttached = false;
		} else {
		ALOGW("Unable to detach current thread from JVM");
		}
		}

		private:
		DISALLOW_COPY_AND_ASSIGN(JavaThreadAttacher);
		bool mAttached = false;
		};
		} // namespace

		void RpcSession::join(sp<RpcSession>&& session, PreJoinSetupResult&& setupResult) {
		sp<RpcConnection>& connection = setupResult.connection;

		if (setupResult.status == OK) {
		JavaThreadAttacher javaThreadAttacher;
		while (true) {
		status_t status = session->state()->getAndExecuteCommand(connection, session,
		RpcState::CommandType::ANY);

libs/binder/tests/binderRpcTest.cpp

+37 −0

Original line number	Diff line number	Diff line
		@@ -1208,6 +1208,43 @@ TEST(BinderRpc, Shutdown) {
		<< "After server->shutdown() returns true, join() did not stop after 2s";
		}

		TEST(BinderRpc, Java) {
		#if !defined(__ANDROID__)
		GTEST_SKIP() << "This test is only run on Android. Though it can technically run on host on"
		"createRpcDelegateServiceManager() with a device attached, such test belongs "
		"to binderHostDeviceTest. Hence, just disable this test on host.";
		#endif // !__ANDROID__
		sp<IServiceManager> sm = defaultServiceManager();
		ASSERT_NE(nullptr, sm);
		// Any Java service with non-empty getInterfaceDescriptor() would do.
		// Let's pick batteryproperties.
		auto binder = sm->checkService(String16("batteryproperties"));
		ASSERT_NE(nullptr, binder);
		auto descriptor = binder->getInterfaceDescriptor();
		ASSERT_GE(descriptor.size(), 0);
		ASSERT_EQ(OK, binder->pingBinder());

		auto rpcServer = RpcServer::make();
		rpcServer->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
		unsigned int port;
		ASSERT_TRUE(rpcServer->setupInetServer(0, &port));
		auto socket = rpcServer->releaseServer();

		auto keepAlive = sp<BBinder>::make();
		ASSERT_EQ(OK, binder->setRpcClientDebug(std::move(socket), keepAlive));

		auto rpcSession = RpcSession::make();
		ASSERT_TRUE(rpcSession->setupInetClient("127.0.0.1", port));
		auto rpcBinder = rpcSession->getRootObject();
		ASSERT_NE(nullptr, rpcBinder);

		ASSERT_EQ(OK, rpcBinder->pingBinder());

		ASSERT_EQ(descriptor, rpcBinder->getInterfaceDescriptor())
		<< "getInterfaceDescriptor should not crash system_server";
		ASSERT_EQ(OK, rpcBinder->pingBinder());
		}

		} // namespace android

		int main(int argc, char** argv) {