make Looper, Handler, and MessageQueue work properly

this for example makes Unity apps not steal the main thread,
hanging Gtk.

meson.build

@@ -59,6 +59,7 @@ libandroid_so = shared_library('android', [
 libtranslationlayer_so = shared_library('translation_layer_main', [
                                                                   	'src/api-impl-jni/egl/com_google_android_gles_jni_EGLImpl.c',
                                                                   	'src/api-impl-jni/android_os_Environment.c',
+                                                                  	'src/api-impl-jni/android_os_MessageQueue.c',
                                                                   	'src/api-impl-jni/android_os_SystemClock.c',
                                                                   	'src/api-impl-jni/android_view_Window.c',
                                                                   	'src/api-impl-jni/util.c',

src/api-impl-jni/android_os_MessageQueue.c

@@ -0,0 +1,62 @@
+#include "defines.h"
+#include "util.h"
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+/* TODO put these in a header */
+typedef void ALooper;
+ALooper * ALooper_prepare(void);
+void ALooper_wake(ALooper *looper);
+bool ALooper_isPolling(ALooper *looper);
+int ALooper_pollOnce(int timeoutMillis, int* outFd, int* outEvents, void** outData);
+
+struct native_message_queue {
+	ALooper *looper;
+	bool in_callback;
+};
+
+JNIEXPORT jlong JNICALL Java_android_os_MessageQueue_nativeInit(JNIEnv *env, jclass this)
+{
+	struct native_message_queue *message_queue = malloc(sizeof(struct native_message_queue));
+
+	message_queue->in_callback = false;
+	message_queue->looper = ALooper_prepare();
+
+	return _INTPTR(message_queue);
+}
+
+JNIEXPORT void JNICALL Java_android_os_MessageQueue_nativeDestroy(JNIEnv *env, jclass this, jlong ptr)
+{
+	struct native_message_queue *message_queue = _PTR(ptr);
+
+	free(message_queue);
+}
+
+JNIEXPORT void JNICALL Java_android_os_MessageQueue_nativePollOnce(JNIEnv *env, jclass this, jlong ptr, jint timeout_millis)
+{
+	struct native_message_queue *message_queue = _PTR(ptr);
+
+//	printf("Java_android_os_MessageQueue_nativePollOnce: entry (timeout: %d)\n", timeout_millis);
+	message_queue->in_callback = true;
+	ALooper_pollOnce(timeout_millis, NULL, NULL, NULL);
+	message_queue->in_callback = false;
+//	printf("Java_android_os_MessageQueue_nativePollOnce: exit\n");
+
+	/* TODO: what's with the exception stuff */
+}
+
+JNIEXPORT void JNICALL Java_android_os_MessageQueue_nativeWake(JNIEnv *env, jclass this, jlong ptr)
+{
+	struct native_message_queue *message_queue = _PTR(ptr);
+
+	ALooper_wake(message_queue->looper);
+}
+
+JNIEXPORT jboolean JNICALL Java_android_os_MessageQueue_nativeIsIdling(JNIEnv *env, jclass this, jlong ptr)
+{
+	struct native_message_queue *message_queue = _PTR(ptr);
+
+	return ALooper_isPolling(message_queue->looper);
+}

src/api-impl-jni/android_os_SystemClock.c

@@ -1,3 +1,6 @@
+#include <time.h>
+#include <math.h>
+
 #include "generated_headers/android_os_SystemClock.h"
 
 JNIEXPORT jlong JNICALL Java_android_os_SystemClock_elapsedRealtime(JNIEnv *env, jclass this)
@@ -5,3 +8,10 @@ JNIEXPORT jlong JNICALL Java_android_os_SystemClock_elapsedRealtime(JNIEnv *env,
 	printf("FIXME: Java_android_os_SystemClock_elapsedRealtime: returning 0\n");
 	return 0; // FIXME
 }
+
+JNIEXPORT jlong JNICALL Java_android_os_SystemClock_uptimeMillis(JNIEnv *env, jclass this)
+{
+    struct timespec t;
+    clock_gettime(CLOCK_REALTIME, &t);
+    return t.tv_sec * 1000 + lround(t.tv_nsec / 1e6);
+}

src/api-impl-jni/generated_headers/android_os_MessageQueue.h

@@ -10,42 +10,42 @@ extern "C" {
 /*
  * Class:     android_os_MessageQueue
  * Method:    nativeInit
- * Signature: ()I
+ * Signature: ()J
  */
-JNIEXPORT jint JNICALL Java_android_os_MessageQueue_nativeInit
+JNIEXPORT jlong JNICALL Java_android_os_MessageQueue_nativeInit
   (JNIEnv *, jclass);
 
 /*
  * Class:     android_os_MessageQueue
  * Method:    nativeDestroy
- * Signature: (I)V
+ * Signature: (J)V
  */
 JNIEXPORT void JNICALL Java_android_os_MessageQueue_nativeDestroy
-  (JNIEnv *, jclass, jint);
+  (JNIEnv *, jclass, jlong);
 
 /*
  * Class:     android_os_MessageQueue
  * Method:    nativePollOnce
- * Signature: (II)V
+ * Signature: (JI)V
  */
 JNIEXPORT void JNICALL Java_android_os_MessageQueue_nativePollOnce
-  (JNIEnv *, jclass, jint, jint);
+  (JNIEnv *, jclass, jlong, jint);
 
 /*
  * Class:     android_os_MessageQueue
  * Method:    nativeWake
- * Signature: (I)V
+ * Signature: (J)V
  */
 JNIEXPORT void JNICALL Java_android_os_MessageQueue_nativeWake
-  (JNIEnv *, jclass, jint);
+  (JNIEnv *, jclass, jlong);
 
 /*
  * Class:     android_os_MessageQueue
  * Method:    nativeIsIdling
- * Signature: (I)Z
+ * Signature: (J)Z
  */
 JNIEXPORT jboolean JNICALL Java_android_os_MessageQueue_nativeIsIdling
-  (JNIEnv *, jclass, jint);
+  (JNIEnv *, jclass, jlong);
 
 #ifdef __cplusplus
 }

src/api-impl-jni/generated_headers/android_os_SystemClock.h

@@ -15,6 +15,14 @@ extern "C" {
 JNIEXPORT jboolean JNICALL Java_android_os_SystemClock_setCurrentTimeMillis
   (JNIEnv *, jclass, jlong);
 
+/*
+ * Class:     android_os_SystemClock
+ * Method:    uptimeMillis
+ * Signature: ()J
+ */
+JNIEXPORT jlong JNICALL Java_android_os_SystemClock_uptimeMillis
+  (JNIEnv *, jclass);
+
 /*
  * Class:     android_os_SystemClock
  * Method:    elapsedRealtime

src/api-impl/android/app/Activity.java

@@ -6,6 +6,8 @@ import android.content.Intent;
 import android.content.res.Configuration;
 import android.content.res.XmlResourceParser;
 import android.os.Bundle;
+import android.os.Handler;
+import android.os.Looper;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -102,6 +104,12 @@ public class Activity extends Context {
 	protected void onCreate(Bundle savedInstanceState) {
 		System.out.println("- onCreate - yay!");
 
+		/* TODO: this probably belongs elsewhere, but this is our entry point for better or worse */
+		Looper looper = Looper.myLooper();
+		if(looper == null) {
+			Looper.prepareMainLooper();
+		}
+
 		return;
 	}
 
@@ -212,7 +220,11 @@ public class Activity extends Context {
 	}
 
 	public final void runOnUiThread(Runnable action) {
-		action.run(); // FIXME: running synchronously for now
+		if(Looper.myLooper() == Looper.getMainLooper()) {
+			action.run();
+		} else {
+			new Handler(Looper.getMainLooper()).post(action);
+		}
 	}
 
 	protected void onActivityResult(int requestCode, int resultCode, Intent data) {}

src/api-impl/android/content/Context.java

@@ -33,6 +33,7 @@ import android.view.WindowManager;
 import android.view.WindowManagerImpl;
 import java.io.File;
 import java.io.FileInputStream;
+import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 
 public class Context extends Object {
@@ -138,8 +139,14 @@ public class Context extends Object {
 	}
 
 	public Looper getMainLooper() {
-		System.out.println("returning the main Looper, most definitely doing just that!");
-		return new Looper();
+		/* TODO: this is not what AOSP does, which could be a problem */
+		Looper looper = Looper.myLooper();
+		if(looper == null) {
+			Looper.prepare();
+			looper = Looper.myLooper();
+		}
+
+		return looper;
 	}
 
 	public String getPackageName() {
@@ -251,9 +258,12 @@ public class Context extends Object {
 		return new ComponentName("", "");
 	}
 
-	// FIXME - it should be *trivial* to do actually implement this
-	public FileInputStream openFileInput(String name) {
-		return null;
+	// TODO: do these both work? make them look more alike
+	public FileInputStream openFileInput(String name) throws FileNotFoundException {
+		System.out.println("openFileInput called for: '" + name + "'");
+		File file = new File(getFilesDir(), name);
+
+		return new FileInputStream(file);
 	}
 
 	public FileOutputStream openFileOutput(String name, int mode) throws java.io.FileNotFoundException {

src/api-impl/android/os/Bundle.java

@@ -738,6 +738,7 @@ public final class Bundle implements Cloneable {
 	 */
 	public boolean getBoolean(String key, boolean defaultValue) {
 		Object o = mMap.get(key);
+		System.out.println("bundle.getBoolean(" + key + ", " + defaultValue + ") called");
 		if (o == null) {
 			return defaultValue;
 		}

src/api-impl/android/os/Handler.java

@@ -225,7 +225,7 @@ public class Handler {
 	 */
 	public Handler(Looper looper, Callback callback, boolean async) {
 		mLooper = looper;
-		mQueue = null /*looper.mQueue*/;
+		mQueue = looper.mQueue;
 		mCallback = callback;
 		mAsynchronous = async;
 	}
@@ -316,9 +316,7 @@ public class Handler {
 	 *         looper processing the message queue is exiting.
 	 */
 	public final boolean post(Runnable r) {
-		//       return  sendMessageDelayed(getPostMessage(r), 0);
-		r.run();
-		return true;
+		return sendMessageDelayed(getPostMessage(r), 0);
 	}
 
 	/**
@@ -571,29 +569,14 @@ public class Handler {
 	 *         occurs then the message will be dropped.
 	 */
 	public boolean sendMessageAtTime(Message msg, long uptimeMillis) {
-		/*        MessageQueue queue = mQueue;
+		MessageQueue queue = mQueue;
 		if (queue == null) {
 			RuntimeException e = new RuntimeException(
 			    this + " sendMessageAtTime() called with no mQueue");
 			Log.w("Looper", e.getMessage(), e);
 			return false;
 		}
-			return enqueueMessage(queue, msg, uptimeMillis);*/
-		if (mCallback != null) {
-			//			System.out.println("Handler.sendMessageAtTime: directly calling mCallback.handleMessage)");
-			if (msg.callback != null) {
-				msg.callback.run();
-			}
-			return mCallback.handleMessage(msg);
-		} else {
-			//			System.out.println("Handler.sendMessageAtTime: not directly calling mCallback.handleMessage - mCallback is null)");
-			/* do this in this case as well?
-						if(msg.callback != null) {
-							msg.callback.run();
-						}
-			*/
-			return true; // false?
-		}
+		return enqueueMessage(queue, msg, uptimeMillis);
 	}
 
 	/**
@@ -609,15 +592,14 @@ public class Handler {
 	 *         looper processing the message queue is exiting.
 	 */
 	public final boolean sendMessageAtFrontOfQueue(Message msg) {
-		/*MessageQueue queue = mQueue;
+		MessageQueue queue = mQueue;
 		if (queue == null) {
 			RuntimeException e = new RuntimeException(
 			    this + " sendMessageAtTime() called with no mQueue");
 			Log.w("Looper", e.getMessage(), e);
 			return false;
 		}
-		return enqueueMessage(queue, msg, 0);*/
-		return true;
+		return enqueueMessage(queue, msg, 0);
 	}
 
 	private boolean enqueueMessage(MessageQueue queue, Message msg, long uptimeMillis) {

src/api-impl/android/os/HandlerThread.java

@@ -1,19 +1,149 @@
+/*
+ * Copyright (C) 2006 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package android.os;
 
+/**
+ * Handy class for starting a new thread that has a looper. The looper can then be
+ * used to create handler classes. Note that start() must still be called.
+ */
 public class HandlerThread extends Thread {
-	String name;
-
-	public HandlerThread() {}
+	int mPriority;
+	int mTid = -1;
+	Looper mLooper;
 
 	public HandlerThread(String name) {
-		this.name = name;
+		super(name);
+		mPriority = Process.THREAD_PRIORITY_DEFAULT;
 	}
 
-	public void start() {
-		// if(name.equals("FlurryAgent")) { return; }
+	/**
+	 * Constructs a HandlerThread.
+	 * @param name
+	 * @param priority The priority to run the thread at. The value supplied must be from
+	 * {@link android.os.Process} and not from java.lang.Thread.
+	 */
+	public HandlerThread(String name, int priority) {
+		super(name);
+		mPriority = priority;
 	}
 
+	/**
+	 * Call back method that can be explicitly overridden if needed to execute some
+	 * setup before Looper loops.
+	 */
+	protected void onLooperPrepared() {
+	}
+
+	@Override
+	public void run() {
+		mTid = Process.myTid();
+		Looper.prepare();
+		synchronized (this) {
+			mLooper = Looper.myLooper();
+			notifyAll();
+		}
+		Process.setThreadPriority(mPriority);
+		onLooperPrepared();
+		Looper.loop();
+		mTid = -1;
+	}
+
+	/**
+	 * This method returns the Looper associated with this thread. If this thread not been started
+	 * or for any reason is isAlive() returns false, this method will return null. If this thread
+	 * has been started, this method will block until the looper has been initialized.
+	 * @return The looper.
+	 */
 	public Looper getLooper() {
-		return new Looper();
+		if (!isAlive()) {
+			return null;
+		}
+
+		// If the thread has been started, wait until the looper has been created.
+		synchronized (this) {
+			while (isAlive() && mLooper == null) {
+				try {
+					wait();
+				} catch (InterruptedException e) {
+				}
+			}
+		}
+		return mLooper;
+	}
+
+	/**
+	 * Quits the handler thread's looper.
+	 * <p>
+	 * Causes the handler thread's looper to terminate without processing any
+	 * more messages in the message queue.
+	 * </p><p>
+	 * Any attempt to post messages to the queue after the looper is asked to quit will fail.
+	 * For example, the {@link Handler#sendMessage(Message)} method will return false.
+	 * </p><p class="note">
+	 * Using this method may be unsafe because some messages may not be delivered
+	 * before the looper terminates.  Consider using {@link #quitSafely} instead to ensure
+	 * that all pending work is completed in an orderly manner.
+	 * </p>
+	 *
+	 * @return True if the looper looper has been asked to quit or false if the
+	 * thread had not yet started running.
+	 *
+	 * @see #quitSafely
+	 */
+	public boolean quit() {
+		Looper looper = getLooper();
+		if (looper != null) {
+			looper.quit();
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	 * Quits the handler thread's looper safely.
+	 * <p>
+	 * Causes the handler thread's looper to terminate as soon as all remaining messages
+	 * in the message queue that are already due to be delivered have been handled.
+	 * Pending delayed messages with due times in the future will not be delivered.
+	 * </p><p>
+	 * Any attempt to post messages to the queue after the looper is asked to quit will fail.
+	 * For example, the {@link Handler#sendMessage(Message)} method will return false.
+	 * </p><p>
+	 * If the thread has not been started or has finished (that is if
+	 * {@link #getLooper} returns null), then false is returned.
+	 * Otherwise the looper is asked to quit and true is returned.
+	 * </p>
+	 *
+	 * @return True if the looper looper has been asked to quit or false if the
+	 * thread had not yet started running.
+	 */
+	public boolean quitSafely() {
+		Looper looper = getLooper();
+		if (looper != null) {
+			looper.quitSafely();
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	 * Returns the identifier of this thread. See Process.myTid().
+	 */
+	public int getThreadId() {
+		return mTid;
 	}
 }

src/api-impl/android/os/Looper.java

@@ -53,13 +53,6 @@ import android.util.Printer;
 public final class Looper {
 	private static final String TAG = "Looper";
 
-	// FIXME
-	public Looper() {
-		mQueue = null;
-		mThread = Thread.currentThread();
-		System.out.println("making a fake Looper object, let's hope noone tries to actually use it");
-	}
-
 	// sThreadLocal.get() will return null unless you've called prepare().
 	static final ThreadLocal<Looper> sThreadLocal = new ThreadLocal<Looper>();
 	private static Looper sMainLooper; // guarded by Looper.class
@@ -84,7 +77,7 @@ public final class Looper {
 		if (sThreadLocal.get() != null) {
 			throw new RuntimeException("Only one Looper may be created per thread");
 		}
-		sThreadLocal.set(new Looper(/*quitAllowed*/));
+		sThreadLocal.set(new Looper(quitAllowed));
 	}
 
 	/**
@@ -107,10 +100,9 @@ public final class Looper {
 	 * Returns the application's main looper, which lives in the main thread of the application.
 	 */
 	public static Looper getMainLooper() {
-		return new Looper();
-		/*        synchronized (Looper.class) {
+		synchronized (Looper.class) {
 			return sMainLooper;
-			}*/
+		}
 	}
 
 	/**
@@ -118,8 +110,7 @@ public final class Looper {
 	 * {@link #quit()} to end the loop.
 	 */
 	public static void loop() {
-		System.out.println("oops, Looper.loop called... and we don't implement that");
-		/*final Looper me = myLooper();
+		final Looper me = myLooper();
 		if (me == null) {
 			throw new RuntimeException("No Looper; Looper.prepare() wasn't called on this thread.");
 		}
@@ -127,8 +118,8 @@ public final class Looper {
 
 		// Make sure the identity of this thread is that of the local process,
 		// and keep track of what that identity token actually is.
-	//        Binder.clearCallingIdentity();
-	//        final long ident = Binder.clearCallingIdentity();
+//		Binder.clearCallingIdentity();
+//		final long ident = Binder.clearCallingIdentity();
 
 		for (;;) {
 			Message msg = queue.next(); // might block
@@ -152,17 +143,13 @@ public final class Looper {
 
 			// Make sure that during the course of dispatching the
 			// identity of the thread wasn't corrupted.
-	//            final long newIdent = Binder.clearCallingIdentity();
-	/*            if (ident != newIdent) {
-			Log.wtf(TAG, "Thread identity changed from 0x"
-				+ Long.toHexString(ident) + " to 0x"
-				+ Long.toHexString(newIdent) + " while dispatching to "
-				+ msg.target.getClass().getName() + " "
-				+ msg.callback + " what=" + msg.what);
-		    }* /
-
+/*			final long newIdent = Binder.clearCallingIdentity();
+			if (ident != newIdent) {
+				Log.wtf(TAG, "Thread identity changed from 0x" + Long.toHexString(ident) + " to 0x" + Long.toHexString(newIdent) + " while dispatching to " + msg.target.getClass().getName() + " " + msg.callback + " what=" + msg.what);
+			}
+*/
 			msg.recycle();
-		}*/
+		}
 	}
 
 	/**
@@ -170,11 +157,7 @@ public final class Looper {
 	 * null if the calling thread is not associated with a Looper.
 	 */
 	public static Looper myLooper() {
-		return new Looper();
-		/*		if(sThreadLocal.get() == null) {
-					prepare(false);
-				}
-			return sThreadLocal.get();*/
+		return sThreadLocal.get();
 	}
 
 	/**
@@ -293,8 +276,7 @@ public final class Looper {
 	 * Return the Thread associated with this Looper.
 	 */
 	public Thread getThread() {
-		return Thread.currentThread(); // ugly hack
-					       //        return mThread;
+		return mThread;
 	}
 
 	/**

src/api-impl/android/os/MessageQueue.java

@@ -34,7 +34,7 @@ public final class MessageQueue {
 	private final boolean mQuitAllowed;
 
 	@SuppressWarnings("unused")
-	private int mPtr; // used by native code
+	private long mPtr; // used by native code
 
 	Message mMessages;
 	private final ArrayList<IdleHandler> mIdleHandlers = new ArrayList<IdleHandler>();
@@ -48,11 +48,11 @@ public final class MessageQueue {
 	// Barriers are indicated by messages with a null target whose arg1 field carries the token.
 	private int mNextBarrierToken;
 
-	private native static int nativeInit();
-	private native static void nativeDestroy(int ptr);
-	private native static void nativePollOnce(int ptr, int timeoutMillis);
-	private native static void nativeWake(int ptr);
-	private native static boolean nativeIsIdling(int ptr);
+	private native static long nativeInit();
+	private native static void nativeDestroy(long ptr);
+	private native static void nativePollOnce(long ptr, int timeoutMillis);
+	private native static void nativeWake(long ptr);
+	private native static boolean nativeIsIdling(long ptr);
 
 	/**
 	 * Callback interface for discovering when a thread is going to block

src/api-impl/android/os/SystemClock.java

@@ -105,16 +105,13 @@ public final class SystemClock {
 	 * @param ms to sleep before returning, in milliseconds of uptime.
 	 */
 	public static void sleep(long ms) {
-		System.out.println("!!! sleep(...) doesn't work, need to implement uptimeMillis");
-	/*
 		long start = uptimeMillis();
 		long duration = ms;
 		boolean interrupted = false;
 		do {
 			try {
 				Thread.sleep(duration);
-            }
-            catch (InterruptedException e) {
+			} catch (InterruptedException e) {
 				interrupted = true;
 			}
 			duration = start + ms - uptimeMillis();
@@ -126,7 +123,7 @@ public final class SystemClock {
 			// call to Thread.sleep() or Object.wait() will be interrupted.
 			Thread.currentThread().interrupt();
 		}
-    */}
+	}
 
 	/**
 	 * Sets the current wall time, in milliseconds.  Requires the calling
@@ -141,9 +138,7 @@ public final class SystemClock {
 	 *
 	 * @return milliseconds of non-sleep uptime since boot.
 	 */
-	/*native */ public static long uptimeMillis() {
-		return 654000; // FIXME
-	}
+	native public static long uptimeMillis();
 
 	/**
 	 * Returns milliseconds since boot, including time spent in sleep.

src/libandroid/looper.c

@@ -1,3 +1,4 @@
+#include <stdbool.h>
 #include <stddef.h>
 #include <stdio.h>
 
@@ -37,7 +38,7 @@ void ALooper_release(ALooper* looper) {
     _ZNK7android7RefBase9decStrongEPKv(looper, (void*)ALooper_acquire);
 }
 
-int _ZN7android6Looper7pollAllEiPiS1_PPv(ALooper *this, int timeoutMillis, int* outFd, int* outEvents, void** outData);
+int _ZN7android6Looper7pollAllEiPiS1_PPv(ALooper *this, int timeoutMillis, int *outFd, int *outEvents, void **outData);
 int ALooper_pollAll(int timeoutMillis, int* outFd, int* outEvents, void** outData)
 {
 	ALooper *looper = ALooper_forThread();
@@ -49,12 +50,34 @@ int ALooper_pollAll(int timeoutMillis, int* outFd, int* outEvents, void** outDat
 	return _ZN7android6Looper7pollAllEiPiS1_PPv(looper, timeoutMillis, outFd, outEvents,  outData);
 }
 
-int _ZN7android6Looper5addFdEiiiPFiiiPvES1_(ALooper *this, int fd, int ident, int events, Looper_callbackFunc callback, void* data);
+int _ZN7android6Looper8pollOnceEiPiS1_PPv(ALooper *this, int timeoutMillis, int *outFd, int *outEvents, void **outData);
+int ALooper_pollOnce(int timeoutMillis, int* outFd, int* outEvents, void** outData)
+{
+	ALooper *looper = ALooper_forThread();
+	if(!looper) {
+		fprintf(stderr, "ALooper_pollAll: ALooper_forThread returned NULL\n");
+		return 0;
+	}
+
+	return _ZN7android6Looper8pollOnceEiPiS1_PPv(looper, timeoutMillis, outFd, outEvents,  outData);
+}
+
+int _ZN7android6Looper5addFdEiiiPFiiiPvES1_(ALooper *this, int fd, int ident, int events, Looper_callbackFunc callback, void *data);
 int ALooper_addFd(ALooper* looper, int fd, int ident, int events, Looper_callbackFunc callback, void* data)
 {
 	return _ZN7android6Looper5addFdEiiiPFiiiPvES1_(looper, fd, ident, events, callback, data);
 }
+
 void _ZN7android6Looper4wakeEv(ALooper *this);
-void ALooper_wake(ALooper* looper) {
+void ALooper_wake(ALooper *looper)
+{
 	_ZN7android6Looper4wakeEv(looper);
 }
+
+/* this is not part of the android API, but we use it internally */
+
+bool _ZNK7android6Looper9isPollingEv(ALooper *this);
+bool ALooper_isPolling(ALooper *looper)
+{
+	return _ZNK7android6Looper9isPollingEv(looper);
+}