LocalOnlyHotspotRequestInfo: track LOHS requests

Add a new class to keep track of apps Binder instances that request
LocalOnlyHotspot.  When the app dies, it will trigger a callback to
remove the request.  We will also unlinkToDeath when the app calls to
stop using LocalOnlyHotspot.  This object also contains a Messenger that
will allow WifiServiceImpl to communicate updates to WifiManager for the
requesting app.

Bug: 36732530
Test: frameworks/opt/net/wifi/tests/wifitests/runtests.sh

Change-Id: Ia366a3cc7339cdea94a137d62905b15b72cf05c0

2 files changed, 247 insertions, 0 deletions

diff --git a/service/java/com/android/server/wifi/LocalOnlyHotspotRequestInfo.java b/service/java/com/android/server/wifi/LocalOnlyHotspotRequestInfo.java
new file mode 100644
index 000000000..2925d966b
--- /dev/null
+++ b/service/java/com/android/server/wifi/LocalOnlyHotspotRequestInfo.java
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2017 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 com.android.server.wifi;
+
+import android.annotation.NonNull;
+import android.os.Binder;
+import android.os.IBinder;
+import android.os.Message;
+import android.os.Messenger;
+import android.os.RemoteException;
+
+import com.android.internal.util.Preconditions;
+
+/**
+ * Tracks information about applications requesting use of the LocalOnlyHotspot.
+ *
+ * @hide
+ */
+public class LocalOnlyHotspotRequestInfo implements IBinder.DeathRecipient {
+    private final int mUid;
+    private final IBinder mBinder;
+    private final RequestingApplicationDeathCallback mCallback;
+    private final Messenger mMessenger;
+
+    /**
+     * Callback for use with LocalOnlyHotspot to unregister requesting applications upon death.
+     */
+    public interface RequestingApplicationDeathCallback {
+        /**
+         * Called when requesting app has died.
+         */
+        void onLocalOnlyHotspotRequestorDeath(LocalOnlyHotspotRequestInfo requestor);
+    }
+
+    LocalOnlyHotspotRequestInfo(@NonNull IBinder binder, @NonNull Messenger messenger,
+            @NonNull RequestingApplicationDeathCallback callback) {
+        mUid = Binder.getCallingUid();
+        mBinder = Preconditions.checkNotNull(binder);
+        mMessenger = Preconditions.checkNotNull(messenger);
+        mCallback = Preconditions.checkNotNull(callback);
+
+        try {
+            mBinder.linkToDeath(this, 0);
+        } catch (RemoteException e) {
+            binderDied();
+        }
+    }
+
+    /**
+     * Allow caller to unlink this object from binder death.
+     */
+    public void unlinkDeathRecipient() {
+        mBinder.unlinkToDeath(this, 0);
+    }
+
+    /**
+     * Application requesting LocalOnlyHotspot died
+     */
+    @Override
+    public void binderDied() {
+        mCallback.onLocalOnlyHotspotRequestorDeath(this);
+    }
+
+    /**
+     * Send a message to WifiManager for the calling application.
+     *
+     * @param what Message type to send
+     * @param arg1 arg1 for the message
+     *
+     * @throws RemoteException
+     */
+    public void sendMessage(int what, int arg1) throws RemoteException {
+        Message message = Message.obtain();
+        message.what = what;
+        message.arg1 = arg1;
+        mMessenger.send(message);
+    }
+
+    public int getUid() {
+        return mUid;
+    }
+}
diff --git a/tests/wifitests/src/com/android/server/wifi/LocalOnlyHotspotRequestInfoTest.java b/tests/wifitests/src/com/android/server/wifi/LocalOnlyHotspotRequestInfoTest.java
new file mode 100644
index 000000000..0e8ead2e6
--- /dev/null
+++ b/tests/wifitests/src/com/android/server/wifi/LocalOnlyHotspotRequestInfoTest.java
@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2017 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 com.android.server.wifi;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.Mockito.any;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.eq;
+import static org.mockito.Mockito.verify;
+
+import android.os.Handler;
+import android.os.IBinder;
+import android.os.Message;
+import android.os.Messenger;
+import android.os.Process;
+import android.os.RemoteException;
+import android.os.test.TestLooper;
+import android.test.suitebuilder.annotation.SmallTest;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+/*
+ * Unit tests for {@link com.android.server.wifi.LocalOnlyHotspotRequestInfo}.
+ */
+@SmallTest
+public class LocalOnlyHotspotRequestInfoTest {
+
+    private static final String TAG = "LocalOnlyHotspotRequestInfoTest";
+    @Mock IBinder mAppBinder;
+    @Mock LocalOnlyHotspotRequestInfo.RequestingApplicationDeathCallback mCallback;
+    private Handler mHandler;
+    private Messenger mMessenger;
+    private TestLooper mTestLooper;
+    RemoteException mRemoteException;
+    private LocalOnlyHotspotRequestInfo mLOHSRequestInfo;
+
+    /**
+     * Setup test.
+     */
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mTestLooper = new TestLooper();
+        mHandler = new Handler(mTestLooper.getLooper());
+        mMessenger = new Messenger(mHandler);
+        mRemoteException = new RemoteException("Test Remote Exception");
+    }
+
+    /**
+     * Make sure we link the call to request LocalOnlyHotspot by an app is linked to their Binder
+     * call.  This allows us to clean up if the app dies.
+     */
+    @Test
+    public void verifyBinderLinkToDeathIsCalled() throws Exception {
+        mLOHSRequestInfo = new LocalOnlyHotspotRequestInfo(mAppBinder, mMessenger, mCallback);
+        verify(mAppBinder).linkToDeath(eq(mLOHSRequestInfo), eq(0));
+    }
+
+    /**
+     * Calls to create the requestor to binder death should not pass null callback.
+     */
+    @Test(expected = NullPointerException.class)
+    public void verifyNullCallbackChecked() throws Exception {
+        mLOHSRequestInfo = new LocalOnlyHotspotRequestInfo(mAppBinder, mMessenger, null);
+    }
+
+    /**
+     * Calls to create the request info object should not pass a null messenger.
+     */
+    @Test(expected = NullPointerException.class)
+    public void verifyNullMessengerChecked() throws Exception {
+        mLOHSRequestInfo = new LocalOnlyHotspotRequestInfo(mAppBinder, null, mCallback);
+    }
+
+    /**
+     * Calls to link the requestor to binder death should not pass null binder
+     */
+    @Test(expected = NullPointerException.class)
+    public void verifyNullBinderChecked() throws Exception {
+        mLOHSRequestInfo = new LocalOnlyHotspotRequestInfo(null, mMessenger, mCallback);
+    }
+
+    /**
+     * Calls to unlink the DeathRecipient should call to unlink from Binder.
+     */
+    @Test
+    public void verifyUnlinkDeathRecipientUnlinksFromBinder() throws Exception {
+        mLOHSRequestInfo = new LocalOnlyHotspotRequestInfo(mAppBinder, mMessenger, mCallback);
+        mLOHSRequestInfo.unlinkDeathRecipient();
+        verify(mAppBinder).unlinkToDeath(eq(mLOHSRequestInfo), eq(0));
+    }
+
+    /**
+     * Binder death notification should trigger a callback on the requestor.
+     */
+    @Test
+    public void verifyBinderDeathTriggersCallback() {
+        mLOHSRequestInfo = new LocalOnlyHotspotRequestInfo(mAppBinder, mMessenger, mCallback);
+        mLOHSRequestInfo.binderDied();
+        verify(mCallback).onLocalOnlyHotspotRequestorDeath(eq(mLOHSRequestInfo));
+    }
+
+    /**
+     * Verify a RemoteException when calling linkToDeath triggers the callback.
+     */
+    @Test
+    public void verifyRemoteExceptionTriggersCallback() throws Exception {
+        doThrow(mRemoteException).when(mAppBinder)
+                .linkToDeath(any(IBinder.DeathRecipient.class), eq(0));
+        mLOHSRequestInfo = new LocalOnlyHotspotRequestInfo(mAppBinder, mMessenger, mCallback);
+        verify(mCallback).onLocalOnlyHotspotRequestorDeath(eq(mLOHSRequestInfo));
+    }
+
+    /**
+     * Verify the uid is properly set.
+     */
+    @Test
+    public void verifyUid() {
+        mLOHSRequestInfo = new LocalOnlyHotspotRequestInfo(mAppBinder, mMessenger, mCallback);
+        assertEquals(Process.myUid(), mLOHSRequestInfo.getUid());
+    }
+
+    /**
+     * Verify that sendMessage does send a Message properly
+     */
+    @Test
+    public void verifySendMessenger() throws Exception {
+        mLOHSRequestInfo = new LocalOnlyHotspotRequestInfo(mAppBinder, mMessenger, mCallback);
+        mLOHSRequestInfo.sendMessage(1, 1);
+        Message message = mTestLooper.nextMessage();
+        assertEquals(1, message.what);
+        assertEquals(1, message.arg1);
+    }
+}