adbd: fix a case where we can fail to join a thread. (e778b3ad) · Commits · e / os / android_system_core

adb/daemon/usb.cpp

+29 −24

Original line number	Diff line number	Diff line
		@@ -260,7 +260,6 @@ struct UsbFfsConnection : public Connection {
		// until it dies, and then report failure to the transport via HandleError, which will
		// eventually result in the transport being destroyed, which will result in UsbFfsConnection
		// being destroyed, which unblocks the open thread and restarts this entire process.
		static constexpr int kInterruptionSignal = SIGUSR1;
		static std::once_flag handler_once;
		std::call_once(handler_once, []() { signal(kInterruptionSignal, [](int) {}); });

		@@ -286,6 +285,7 @@ struct UsbFfsConnection : public Connection {
		} else if (rc == 0) {
		// Something in the kernel presumably went wrong.
		// Close our endpoints, wait for a bit, and then try again.
		StopWorker();
		aio_context_.reset();
		read_fd_.reset();
		write_fd_.reset();
		@@ -311,7 +311,7 @@ struct UsbFfsConnection : public Connection {

		switch (event.type) {
		case FUNCTIONFS_BIND:
		CHECK(!started) << "received FUNCTIONFS_ENABLE while already bound?";
		CHECK(!bound) << "received FUNCTIONFS_BIND while already bound?";
		bound = true;
		break;

		@@ -327,28 +327,7 @@ struct UsbFfsConnection : public Connection {
		}
		}

		pthread_t worker_thread_handle = worker_thread_.native_handle();
		while (true) {
		int rc = pthread_kill(worker_thread_handle, kInterruptionSignal);
		if (rc != 0) {
		LOG(ERROR) << "failed to send interruption signal to worker: " << strerror(rc);
		break;
		}

		std::this_thread::sleep_for(100ms);

		rc = pthread_kill(worker_thread_handle, 0);
		if (rc == 0) {
		continue;
		} else if (rc == ESRCH) {
		break;
		} else {
		LOG(ERROR) << "failed to send interruption signal to worker: " << strerror(rc);
		}
		}

		worker_thread_.join();

		StopWorker();
		aio_context_.reset();
		read_fd_.reset();
		write_fd_.reset();
		@@ -379,6 +358,30 @@ struct UsbFfsConnection : public Connection {
		});
		}

		void StopWorker() {
		pthread_t worker_thread_handle = worker_thread_.native_handle();
		while (true) {
		int rc = pthread_kill(worker_thread_handle, kInterruptionSignal);
		if (rc != 0) {
		LOG(ERROR) << "failed to send interruption signal to worker: " << strerror(rc);
		break;
		}

		std::this_thread::sleep_for(100ms);

		rc = pthread_kill(worker_thread_handle, 0);
		if (rc == 0) {
		continue;
		} else if (rc == ESRCH) {
		break;
		} else {
		LOG(ERROR) << "failed to send interruption signal to worker: " << strerror(rc);
		}
		}

		worker_thread_.join();
		}

		void PrepareReadBlock(IoBlock* block, uint64_t id) {
		block->pending = false;
		block->payload = std::make_shared<Block>(kUsbReadSize);
		@@ -615,6 +618,8 @@ struct UsbFfsConnection : public Connection {
		std::deque<std::unique_ptr<IoBlock>> write_requests_ GUARDED_BY(write_mutex_);
		size_t next_write_id_ GUARDED_BY(write_mutex_) = 0;
		size_t writes_submitted_ GUARDED_BY(write_mutex_) = 0;

		static constexpr int kInterruptionSignal = SIGUSR1;
		};

		void usb_init_legacy();