Avoid NPE when quickly toggling USB debugging state (f6197e8f) · Commits · e / os / android_frameworks_base

services/usb/java/com/android/server/usb/UsbDebuggingManager.java

+123 −69

Original line number	Diff line number	Diff line
		@@ -35,6 +35,7 @@ import android.os.SystemProperties;
		import android.os.UserHandle;
		import android.util.Slog;
		import android.util.Base64;

		import com.android.server.FgThread;

		import java.lang.Thread;
		@@ -48,7 +49,7 @@ import java.io.PrintWriter;
		import java.security.MessageDigest;
		import java.util.Arrays;

		public class UsbDebuggingManager implements Runnable {
		public class UsbDebuggingManager {
		private static final String TAG = "UsbDebuggingManager";
		private static final boolean DEBUG = false;

		@@ -59,32 +60,73 @@ public class UsbDebuggingManager implements Runnable {

		private final Context mContext;
		private final Handler mHandler;
		private Thread mThread;
		private UsbDebuggingThread mThread;
		private boolean mAdbEnabled = false;
		private String mFingerprints;
		private LocalSocket mSocket = null;
		private OutputStream mOutputStream = null;

		public UsbDebuggingManager(Context context) {
		mHandler = new UsbDebuggingHandler(FgThread.get().getLooper());
		mContext = context;
		}

		private void listenToSocket() throws IOException {
		class UsbDebuggingThread extends Thread {
		private boolean mStopped;
		private LocalSocket mSocket;
		private OutputStream mOutputStream;
		private InputStream mInputStream;

		UsbDebuggingThread() {
		super(TAG);
		}

		@Override
		public void run() {
		if (DEBUG) Slog.d(TAG, "Entering thread");
		while (true) {
		synchronized (this) {
		if (mStopped) {
		if (DEBUG) Slog.d(TAG, "Exiting thread");
		return;
		}
		try {
		openSocketLocked();
		} catch (Exception e) {
		/* Don't loop too fast if adbd dies, before init restarts it */
		SystemClock.sleep(1000);
		}
		}
		try {
		listenToSocket();
		} catch (IOException e) {
		/* Don't loop too fast if adbd dies, before init restarts it */
		SystemClock.sleep(1000);
		}
		}
		}

		private void openSocketLocked() throws IOException {
		try {
		byte[] buffer = new byte[BUFFER_SIZE];
		LocalSocketAddress address = new LocalSocketAddress(ADBD_SOCKET,
		LocalSocketAddress.Namespace.RESERVED);
		InputStream inputStream = null;
		mInputStream = null;

		if (DEBUG) Slog.d(TAG, "Creating socket");
		mSocket = new LocalSocket();
		mSocket.connect(address);

		mOutputStream = mSocket.getOutputStream();
		inputStream = mSocket.getInputStream();
		mInputStream = mSocket.getInputStream();
		} catch (IOException ioe) {
		closeSocketLocked();
		throw ioe;
		}
		}

		private void listenToSocket() throws IOException {
		try {
		byte[] buffer = new byte[BUFFER_SIZE];
		while (true) {
		int count = inputStream.read(buffer);
		int count = mInputStream.read(buffer);
		if (count < 0) {
		break;
		}
		@@ -95,45 +137,51 @@ public class UsbDebuggingManager implements Runnable {
		Message msg = mHandler.obtainMessage(UsbDebuggingHandler.MESSAGE_ADB_CONFIRM);
		msg.obj = key;
		mHandler.sendMessage(msg);
		}
		else {
		Slog.e(TAG, "Wrong message: " + (new String(Arrays.copyOfRange(buffer, 0, 2))));
		} else {
		Slog.e(TAG, "Wrong message: "
		+ (new String(Arrays.copyOfRange(buffer, 0, 2))));
		break;
		}
		}
		} finally {
		closeSocket();
		}
		}

		@Override
		public void run() {
		while (mAdbEnabled) {
		try {
		listenToSocket();
		} catch (Exception e) {
		/* Don't loop too fast if adbd dies, before init restarts it */
		SystemClock.sleep(1000);
		synchronized (this) {
		closeSocketLocked();
		}
		}
		}

		private void closeSocket() {
		private void closeSocketLocked() {
		if (DEBUG) Slog.d(TAG, "Closing socket");
		try {
		if (mOutputStream != null) {
		mOutputStream.close();
		mOutputStream = null;
		}
		} catch (IOException e) {
		Slog.e(TAG, "Failed closing output stream: " + e);
		}

		try {
		if (mSocket != null) {
		mSocket.close();
		mSocket = null;
		}
		} catch (IOException ex) {
		Slog.e(TAG, "Failed closing socket: " + ex);
		}
		}

		private void sendResponse(String msg) {
		if (mOutputStream != null) {
		/** Call to stop listening on the socket and exit the thread. */
		void stopListening() {
		synchronized (this) {
		mStopped = true;
		closeSocketLocked();
		}
		}

		void sendResponse(String msg) {
		synchronized (this) {
		if (!mStopped && mOutputStream != null) {
		try {
		mOutputStream.write(msg.getBytes());
		}
		@@ -142,6 +190,8 @@ public class UsbDebuggingManager implements Runnable {
		}
		}
		}
		}
		}

		class UsbDebuggingHandler extends Handler {
		private static final int MESSAGE_ADB_ENABLED = 1;
		@@ -163,7 +213,7 @@ public class UsbDebuggingManager implements Runnable {

		mAdbEnabled = true;

		mThread = new Thread(UsbDebuggingManager.this, TAG);
		mThread = new UsbDebuggingThread();
		mThread.start();

		break;
		@@ -173,16 +223,12 @@ public class UsbDebuggingManager implements Runnable {
		break;

		mAdbEnabled = false;
		closeSocket();

		try {
		mThread.join();
		} catch (Exception ex) {
		if (mThread != null) {
		mThread.stopListening();
		mThread = null;
		}

		mThread = null;
		mOutputStream = null;
		mSocket = null;
		break;

		case MESSAGE_ADB_ALLOW: {
		@@ -199,25 +245,33 @@ public class UsbDebuggingManager implements Runnable {
		writeKey(key);
		}

		sendResponse("OK");
		if (mThread != null) {
		mThread.sendResponse("OK");
		}
		break;
		}

		case MESSAGE_ADB_DENY:
		sendResponse("NO");
		if (mThread != null) {
		mThread.sendResponse("NO");
		}
		break;

		case MESSAGE_ADB_CONFIRM: {
		if ("trigger_restart_min_framework".equals(
		SystemProperties.get("vold.decrypt"))) {
		Slog.d(TAG, "Deferring adb confirmation until after vold decrypt");
		sendResponse("NO");
		if (mThread != null) {
		mThread.sendResponse("NO");
		}
		break;
		}
		String key = (String)msg.obj;
		String fingerprints = getFingerprints(key);
		if ("".equals(fingerprints)) {
		sendResponse("NO");
		if (mThread != null) {
		mThread.sendResponse("NO");
		}
		break;
		}
		mFingerprints = fingerprints;
		@@ -387,7 +441,7 @@ public class UsbDebuggingManager implements Runnable {

		public void dump(FileDescriptor fd, PrintWriter pw) {
		pw.println(" USB Debugging State:");
		pw.println(" Connected to adbd: " + (mOutputStream != null));
		pw.println(" Connected to adbd: " + (mThread != null));
		pw.println(" Last key received: " + mFingerprints);
		pw.println(" User keys:");
		try {