implement Google Cloud Messaging using DBus activatable GActions

This needs https://gitlab.com/android_translation_layer/gcm_service running in the
background.
For D-Bus activation, a D-Bus service file needs to be manually
installed under ~/.local/share/dbus-1/services.

Tested with FCM-Toolbox app.

src/api-impl-jni/content/android_content_Context.c

@@ -175,3 +175,18 @@ JNIEXPORT void JNICALL Java_android_content_Context_nativeRegisterUnifiedPush(JN
 	(*env)->ReleaseStringUTFChars(env, token_jstr, token);
 	(*env)->ReleaseStringUTFChars(env, application_jstr, application);
 }
+
+JNIEXPORT void JNICALL Java_android_content_Context_nativeStartExternalService(JNIEnv *env, jclass this, jstring package_jstr, jobject intent)
+{
+	GVariant *variant = intent_serialize(env, intent);
+	const char *package = (*env)->GetStringUTFChars(env, package_jstr, NULL);
+	char *object_path = g_strdup_printf("/%s", package);
+	g_strdelimit(object_path, ".", '/');
+	GDBusConnection *connection = g_bus_get_sync(G_BUS_TYPE_SESSION, NULL, NULL);
+	GActionGroup *action_group = G_ACTION_GROUP(g_dbus_action_group_get(connection, package, object_path));
+	g_action_group_activate_action(action_group, "startService", variant);
+	g_object_unref(action_group);
+	g_object_unref(connection);
+	g_free(object_path);
+	(*env)->ReleaseStringUTFChars(env, package_jstr, package);
+}

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

@@ -49,6 +49,14 @@ JNIEXPORT void JNICALL Java_android_content_Context_nativeExportUnifiedPush
 JNIEXPORT void JNICALL Java_android_content_Context_nativeRegisterUnifiedPush
   (JNIEnv *, jclass, jstring, jstring);
 
+/*
+ * Class:     android_content_Context
+ * Method:    nativeStartExternalService
+ * Signature: (Ljava/lang/String;Landroid/content/Intent;)V
+ */
+JNIEXPORT void JNICALL Java_android_content_Context_nativeStartExternalService
+  (JNIEnv *, jclass, jstring, jobject);
+
 #ifdef __cplusplus
 }
 #endif

src/api-impl-jni/handle_cache.c

@@ -122,6 +122,8 @@ void set_up_handle_cache(JNIEnv *env)
 	handle_cache.intent.constructor = _METHOD(handle_cache.intent.class, "<init>", "()V");
 	handle_cache.intent.putExtraCharSequence = _METHOD(handle_cache.intent.class, "putExtra", "(Ljava/lang/String;Ljava/lang/CharSequence;)Landroid/content/Intent;");
 	handle_cache.intent.putExtraByteArray = _METHOD(handle_cache.intent.class, "putExtra", "(Ljava/lang/String;[B)Landroid/content/Intent;");
+	handle_cache.intent.putExtraInt = _METHOD(handle_cache.intent.class, "putExtra", "(Ljava/lang/String;I)Landroid/content/Intent;");
+	handle_cache.intent.putExtraLong = _METHOD(handle_cache.intent.class, "putExtra", "(Ljava/lang/String;J)Landroid/content/Intent;");
 	handle_cache.intent.getDataString = _METHOD(handle_cache.intent.class, "getDataString", "()Ljava/lang/String;");
 	handle_cache.intent.setClassName = _METHOD(handle_cache.intent.class, "setClassName", "(Landroid/content/Context;Ljava/lang/String;)Landroid/content/Intent;");
 
@@ -136,4 +138,11 @@ void set_up_handle_cache(JNIEnv *env)
 
 	handle_cache.uri.class = _REF((*env)->FindClass(env, "android/net/Uri"));
 	handle_cache.uri.parse = _STATIC_METHOD(handle_cache.uri.class, "parse", "(Ljava/lang/String;)Landroid/net/Uri;");
+
+	handle_cache.bundle.class = _REF((*env)->FindClass(env, "android/os/Bundle"));
+	handle_cache.bundle.get = _METHOD(handle_cache.bundle.class, "get", "(Ljava/lang/String;)Ljava/lang/Object;");
+	handle_cache.bundle.keySet = _METHOD(handle_cache.bundle.class, "keySet", "()Ljava/util/Set;");
+
+	handle_cache.set.class = _REF((*env)->FindClass(env, "java/util/Set"));
+	handle_cache.set.toArray = _METHOD(handle_cache.set.class, "toArray", "()[Ljava/lang/Object;");
 }

src/api-impl-jni/handle_cache.h

@@ -125,6 +125,8 @@ struct handle_cache {
 		jmethodID constructor;
 		jmethodID putExtraCharSequence;
 		jmethodID putExtraByteArray;
+		jmethodID putExtraInt;
+		jmethodID putExtraLong;
 		jmethodID getDataString;
 		jmethodID setClassName;
 	} intent;
@@ -146,6 +148,15 @@ struct handle_cache {
 		jclass class;
 		jmethodID parse;
 	} uri;
+	struct {
+		jclass class;
+		jmethodID keySet;
+		jmethodID get;
+	} bundle;
+	struct {
+		jclass class;
+		jmethodID toArray;
+	} set;
 };
 
 extern struct handle_cache handle_cache;

src/api-impl-jni/util.c

@@ -249,11 +249,37 @@ GVariant *intent_serialize(JNIEnv *env, jobject intent) {
 	jobject component = _GET_OBJ_FIELD(intent, "component", "Landroid/content/ComponentName;");
 	jstring className_jstr = component ? _GET_OBJ_FIELD(component, "mClass", "Ljava/lang/String;") : NULL;
 	jstring data_jstr = (*env)->CallObjectMethod(env, intent, handle_cache.intent.getDataString);
+	jstring sender_package_jstr = (*env)->CallObjectMethod(env, _GET_STATIC_OBJ_FIELD(handle_cache.context.class, "this_application", "Landroid/app/Application;"), handle_cache.context.get_package_name);
+
+	GVariantBuilder extras_builder;
+	g_variant_builder_init(&extras_builder, G_VARIANT_TYPE_VARDICT);
+	jobject extras = _GET_OBJ_FIELD(intent, "extras", "Landroid/os/Bundle;");
+	jobject extras_key_set = (*env)->CallObjectMethod(env, extras, handle_cache.bundle.keySet);
+	jobjectArray extras_keys = (*env)->CallObjectMethod(env, extras_key_set, handle_cache.set.toArray);
+	jsize extras_keys_length = (*env)->GetArrayLength(env, extras_keys);
+	for (jint i = 0; i < extras_keys_length; i++) {
+		jstring key_jstr = (*env)->GetObjectArrayElement(env, extras_keys, i);
+		jobject value_jobj = (*env)->CallObjectMethod(env, extras, handle_cache.bundle.get, key_jstr);
+		if (!(*env)->IsSameObject(env, _CLASS(key_jstr), _CLASS(value_jobj))) {
+			printf("skipping non-string extra: %s\n", (*env)->GetStringUTFChars(env, key_jstr, NULL));
+			continue;
+		}
+		const char *key = (*env)->GetStringUTFChars(env, key_jstr, NULL);
+		const char *value = (*env)->GetStringUTFChars(env, value_jobj, NULL);
+		g_variant_builder_add(&extras_builder, "{sv}", key, g_variant_new_string(value));
+		(*env)->ReleaseStringUTFChars(env, key_jstr, key);
+		(*env)->ReleaseStringUTFChars(env, value_jobj, value);
+		(*env)->DeleteLocalRef(env, key_jstr);
+		(*env)->DeleteLocalRef(env, value_jobj);
+	}
 
 	const char *action = action_jstr ? (*env)->GetStringUTFChars(env, action_jstr, NULL) : NULL;
 	const char *className = className_jstr ? (*env)->GetStringUTFChars(env, className_jstr, NULL) : NULL;
 	const char *data = data_jstr ? (*env)->GetStringUTFChars(env, data_jstr, NULL) : NULL;
-	GVariant *variant = g_variant_new(INTENT_G_VARIANT_TYPE_STRING, action ?: "", className ?: "", data ?: "");
+	const char *sender_package = sender_package_jstr ? (*env)->GetStringUTFChars(env, sender_package_jstr, NULL) : NULL;
+	GVariant *variant = g_variant_new(INTENT_G_VARIANT_TYPE_STRING, action ?: "", className ?: "", data ?: "", &extras_builder, sender_package);
+	if (sender_package_jstr)
+		(*env)->ReleaseStringUTFChars(env, sender_package_jstr, sender_package);
 	if (action_jstr)
 		(*env)->ReleaseStringUTFChars(env, action_jstr, action);
 	if (className_jstr)
@@ -267,7 +293,8 @@ jobject intent_deserialize(JNIEnv *env, GVariant *variant) {
 	const char *action;
 	const char *className;
 	const char *data;
-	g_variant_get(variant, INTENT_G_VARIANT_TYPE_STRING, &action, &className, &data);
+	GVariantIter *extras;
+	g_variant_get(variant, INTENT_G_VARIANT_TYPE_STRING, &action, &className, &data, &extras, NULL);
 	if (action && action[0] == '\0')
 		action = NULL;
 	if (className && className[0] == '\0')
@@ -281,6 +308,24 @@ jobject intent_deserialize(JNIEnv *env, GVariant *variant) {
 		(*env)->CallObjectMethod(env, intent, handle_cache.intent.setClassName, _GET_STATIC_OBJ_FIELD(handle_cache.context.class, "this_application", "Landroid/app/Application;"), _JSTRING(className));
 	if (data)
 		_SET_OBJ_FIELD(intent, "data", "Landroid/net/Uri;", (*env)->CallStaticObjectMethod(env, handle_cache.uri.class, handle_cache.uri.parse, _JSTRING(data)));
+	const char *key;
+	GVariant *value;
+	while (g_variant_iter_loop(extras, "{sv}", &key, &value)) {
+		if (g_variant_is_of_type(value, G_VARIANT_TYPE_STRING)) {
+			(*env)->CallObjectMethod(env, intent, handle_cache.intent.putExtraCharSequence, _JSTRING(key), _JSTRING(g_variant_get_string(value, NULL)));
+		} else if (g_variant_is_of_type(value, G_VARIANT_TYPE_INT32)) {
+			(*env)->CallObjectMethod(env, intent, handle_cache.intent.putExtraInt, _JSTRING(key), g_variant_get_int32(value));
+		} else if (g_variant_is_of_type(value, G_VARIANT_TYPE_INT64)) {
+			(*env)->CallObjectMethod(env, intent, handle_cache.intent.putExtraLong, _JSTRING(key), g_variant_get_int64(value));
+		} else if (g_variant_is_of_type(value, G_VARIANT_TYPE_BYTESTRING)) {
+			gsize size;
+			const int8_t *message = g_variant_get_fixed_array(value, &size, 1);
+			jbyteArray bytesMessage = (*env)->NewByteArray(env, size);
+			(*env)->SetByteArrayRegion(env, bytesMessage, 0, size, message);
+			(*env)->CallObjectMethod(env, intent, handle_cache.intent.putExtraByteArray, _JSTRING(key), bytesMessage);
+		}
+	}
+	g_variant_iter_free(extras);
 	return intent;
 }
 

src/api-impl-jni/util.h

@@ -57,7 +57,7 @@ void atl_safe_gtk_widget_set_visible(GtkWidget *widget, gboolean visible);
 void atl_safe_gtk_widget_queue_allocate(GtkWidget *widget);
 void atl_safe_gtk_widget_queue_resize(GtkWidget *widget);
 
-#define INTENT_G_VARIANT_TYPE_STRING "(sss)"  // (action, className, data)
+#define INTENT_G_VARIANT_TYPE_STRING "(sssa{sv}s)"  // (action, className, data, extras, sender_package)
 GVariant *intent_serialize(JNIEnv *env, jobject intent);
 jobject intent_deserialize(JNIEnv *env, GVariant *variant);
 const char *intent_actionname_from_type(int type);

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

@@ -60,6 +60,11 @@ public abstract class Service extends ContextWrapper {
 		System.out.println("Service.stopSelf() called");
 	}
 
+	public boolean stopSelfResult(int startId) {
+		System.out.println("Service.stopSelfResult(" + startId + ") called");
+		return true;
+	}
+
 	public void attachBaseContext(Context newBase) {
 		System.out.println("Service.attachBaseContext(" + newBase + ") called");
 	}

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

@@ -2,5 +2,20 @@ package android.content;
 
 public abstract class BroadcastReceiver {
 
-	public abstract void onReceive(Context context, Intent intent);
+	public static class PendingResult {
+
+		public void setResultCode(int resultCode) {}
+
+		public void finish() {}
+	}
+
+	public abstract void onReceive(Context context, Intent intent);
+
+	public boolean isOrderedBroadcast() {
+		return true;
+	}
+
+	public PendingResult goAsync() {
+		return new PendingResult();
+	}
 }

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

@@ -39,8 +39,11 @@ import android.os.Bundle;
 import android.os.Environment;
 import android.os.Handler;
 import android.os.Looper;
+import android.os.Message;
+import android.os.Messenger;
 import android.os.ParcelFileDescriptor;
 import android.os.PowerManager;
+import android.os.RemoteException;
 import android.os.UserManager;
 import android.os.Vibrator;
 import android.telephony.TelephonyManager;
@@ -151,6 +154,7 @@ public class Context extends Object {
 	private static native void nativeOpenFile(int fd);
 	private static native void nativeExportUnifiedPush(String packageName);
 	private static native void nativeRegisterUnifiedPush(String token, String application);
+	private static native void nativeStartExternalService(String packageName, Intent service);
 
 	static Application createApplication(long native_window) throws Exception {
 		Application application;
@@ -467,15 +471,47 @@ public class Context extends Object {
 	public ComponentName startService(Intent intent) {
 		ComponentName component = intent.getComponent();
 		if (component == null) {
-			Slog.w(TAG, "startService: component is null for intent: " + intent);
+			int priority = Integer.MIN_VALUE;
+			for (PackageParser.Service service: pkg.services) {
+				for (PackageParser.IntentInfo intentInfo: service.intents) {
+					if (intentInfo.matchAction(intent.getAction()) && intentInfo.priority > priority) {
+						component = new ComponentName(pkg.packageName, service.className);
+						priority = intentInfo.priority;
+						break;
+					}
+				}
+			}
+		}
+		if (intent.getAction() != null && intent.getAction().startsWith("com.google.android.c2dm")) {
+			nativeStartExternalService("com.google.android.c2dm", intent);
+			// Newer applications use a Messenger instead of a BroadcastReceiver for the return Intent.
+			// To support new and old apps with a common interface, we wrap the Messenger in a BroadcastReceiver
+			final Messenger messenger = (Messenger)intent.getParcelableExtra("google.messenger");
+			if (messenger != null) {
+				receiverMap.put(new IntentFilter("com.google.android.c2dm.intent.REGISTRATION"), new BroadcastReceiver() {
+					@Override
+					public void onReceive(Context context, Intent resultIntent) {
+						try {
+							messenger.send(Message.obtain(null, 0, resultIntent));
+						} catch (RemoteException e) {
+							e.printStackTrace();
+						}
+					}
+				});
+			}
 			return null;
 		}
+		if (component == null) {
+			Slog.w(TAG, "startService: no matching service found for intent: " + intent);
+			return null;
+		}
+		final String className = component.getClassName();
 
 		new Handler(Looper.getMainLooper()).post(new Runnable() {
 			@Override
 			public void run() {
 				try {
-					Class<? extends Service> cls = Class.forName(component.getClassName()).asSubclass(Service.class);
+					Class<? extends Service> cls = Class.forName(className).asSubclass(Service.class);
 					if (!runningServices.containsKey(cls)) {
 						Service service = cls.getConstructor().newInstance();
 						service.attachBaseContext(new Context());

src/api-impl/android/content/pm/PackageParser.java

@@ -2220,6 +2220,8 @@ public class PackageParser {
 
 		outInfo.logo = sa.getResourceId(
 				com.android.internal.R.styleable.AndroidManifestIntentFilter_logo, 0);
+		outInfo.priority = sa.getInt(
+				com.android.internal.R.styleable.AndroidManifestIntentFilter_priority, 0);
 		sa.recycle();
 		int outerDepth = parser.getDepth();
 		int type;
@@ -3881,6 +3883,7 @@ public class PackageParser {
 		public int icon;
 		public int logo;
 		public int preferred;
+		public int priority;
 	}
 
 	public final static class ActivityIntentInfo extends IntentInfo {