audio routing update listener

Implement audio port and audio patch
callback infrastructure for clients to receive
notifications when audio routing changes occur via the
OnAudioPortUpdateListener interface.

Bug: 14815883.

Change-Id: I32cbba64eca7369871aec235ff100de1f0c2d344

2 files changed, 175 insertions, 2 deletions

diff --git a/media/java/android/media/AudioManager.java b/media/java/android/media/AudioManager.java
index bbe5331..e6988b6 100644
--- a/media/java/android/media/AudioManager.java
+++ b/media/java/android/media/AudioManager.java
@@ -41,6 +41,7 @@ import android.view.KeyEvent;
 import java.util.HashMap;
 import java.util.ArrayList;
 
+
 /**
  * AudioManager provides access to volume and ringer mode control.
  * <p>
@@ -61,6 +62,7 @@ public class AudioManager {
     private final boolean mUseVolumeKeySounds;
     private final Binder mToken = new Binder();
     private static String TAG = "AudioManager";
+    AudioPortEventHandler mAudioPortEventHandler;
 
     /**
      * Broadcast intent, a hint for applications that audio is about to become
@@ -438,6 +440,7 @@ public class AudioManager {
                 com.android.internal.R.bool.config_useMasterVolume);
         mUseVolumeKeySounds = mContext.getResources().getBoolean(
                 com.android.internal.R.bool.config_useVolumeKeySounds);
+        mAudioPortEventHandler = new AudioPortEventHandler(this);
     }
 
     private static IAudioService getService()
@@ -3112,17 +3115,19 @@ public class AudioManager {
     }
 
     /**
-     * Register an audio port update listener.
+     * Register an audio port list update listener.
      * @hide
      */
     public void registerAudioPortUpdateListener(OnAudioPortUpdateListener l) {
+        mAudioPortEventHandler.registerListener(l);
     }
 
     /**
-     * Unregister an audio port update listener.
+     * Unregister an audio port list update listener.
      * @hide
      */
     public void unregisterAudioPortUpdateListener(OnAudioPortUpdateListener l) {
+        mAudioPortEventHandler.unregisterListener(l);
     }
 
     //
diff --git a/media/java/android/media/AudioPortEventHandler.java b/media/java/android/media/AudioPortEventHandler.java
new file mode 100644
index 0000000..cd9a4de
--- /dev/null
+++ b/media/java/android/media/AudioPortEventHandler.java
@@ -0,0 +1,168 @@
+/*
+ * Copyright (C) 2014 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.media;
+
+import android.os.Handler;
+import android.os.Looper;
+import android.os.Message;
+import android.util.Log;
+
+import java.util.ArrayList;
+import java.lang.ref.WeakReference;
+
+/**
+ * The AudioPortEventHandler handles AudioManager.OnAudioPortUpdateListener callbacks
+ * posted from JNI
+ * @hide
+ */
+
+class AudioPortEventHandler {
+    private final Handler mHandler;
+    private ArrayList<AudioManager.OnAudioPortUpdateListener> mListeners;
+    private AudioManager mAudioManager;
+
+    private static String TAG = "AudioPortEventHandler";
+
+    private static final int AUDIOPORT_EVENT_PORT_LIST_UPDATED = 1;
+    private static final int AUDIOPORT_EVENT_PATCH_LIST_UPDATED = 2;
+    private static final int AUDIOPORT_EVENT_SERVICE_DIED = 3;
+    private static final int AUDIOPORT_EVENT_NEW_LISTENER = 4;
+
+    AudioPortEventHandler(AudioManager audioManager) {
+        mAudioManager = audioManager;
+        mListeners = new ArrayList<AudioManager.OnAudioPortUpdateListener>();
+
+        // find the looper for our new event handler
+        Looper looper = Looper.myLooper();
+        if (looper == null) {
+            throw new IllegalArgumentException("Calling thread not associated with a looper");
+        }
+
+        mHandler = new Handler(looper) {
+            @Override
+            public void handleMessage(Message msg) {
+                Log.i(TAG, "handleMessage: "+msg.what);
+                ArrayList<AudioManager.OnAudioPortUpdateListener> listeners;
+                synchronized (this) {
+                    if (msg.what == AUDIOPORT_EVENT_NEW_LISTENER) {
+                        listeners = new ArrayList<AudioManager.OnAudioPortUpdateListener>();
+                        if (mListeners.contains(msg.obj)) {
+                            listeners.add((AudioManager.OnAudioPortUpdateListener)msg.obj);
+                        }
+                    } else {
+                        listeners = mListeners;
+                    }
+                }
+                if (listeners.isEmpty()) {
+                    return;
+                }
+                // reset audio port cache if the event corresponds to a change coming
+                // from audio policy service or if mediaserver process died.
+                if (msg.what == AUDIOPORT_EVENT_PORT_LIST_UPDATED ||
+                        msg.what == AUDIOPORT_EVENT_PATCH_LIST_UPDATED ||
+                        msg.what == AUDIOPORT_EVENT_SERVICE_DIED) {
+                    mAudioManager.resetAudioPortGeneration();
+                }
+                ArrayList<AudioPort> ports = new ArrayList<AudioPort>();
+                ArrayList<AudioPatch> patches = new ArrayList<AudioPatch>();
+                if (msg.what != AUDIOPORT_EVENT_SERVICE_DIED) {
+                    int status = mAudioManager.updateAudioPortCache(ports, patches);
+                    if (status != AudioManager.SUCCESS) {
+                        return;
+                    }
+                }
+
+                switch (msg.what) {
+                case AUDIOPORT_EVENT_NEW_LISTENER:
+                case AUDIOPORT_EVENT_PORT_LIST_UPDATED:
+                    AudioPort[] portList = ports.toArray(new AudioPort[0]);
+                    for (int i = 0; i < listeners.size(); i++) {
+                        listeners.get(i).OnAudioPortListUpdate(portList);
+                    }
+                    if (msg.what == AUDIOPORT_EVENT_PORT_LIST_UPDATED) {
+                        break;
+                    }
+                    // FALL THROUGH
+
+                case AUDIOPORT_EVENT_PATCH_LIST_UPDATED:
+                    AudioPatch[] patchList = patches.toArray(new AudioPatch[0]);
+                    for (int i = 0; i < listeners.size(); i++) {
+                        listeners.get(i).OnAudioPatchListUpdate(patchList);
+                    }
+                    break;
+
+                case AUDIOPORT_EVENT_SERVICE_DIED:
+                    for (int i = 0; i < listeners.size(); i++) {
+                        listeners.get(i).OnServiceDied();
+                    }
+                    break;
+
+                default:
+                    break;
+                }
+            }
+        };
+
+        native_setup(new WeakReference<AudioPortEventHandler>(this));
+    }
+    private native void native_setup(Object module_this);
+
+    @Override
+    protected void finalize() {
+        native_finalize();
+    }
+    private native void native_finalize();
+
+    void registerListener(AudioManager.OnAudioPortUpdateListener l) {
+        synchronized (this) {
+            mListeners.add(l);
+        }
+        if (mHandler != null) {
+            Message m = mHandler.obtainMessage(AUDIOPORT_EVENT_NEW_LISTENER, 0, 0, l);
+            mHandler.sendMessage(m);
+        }
+    }
+
+    void unregisterListener(AudioManager.OnAudioPortUpdateListener l) {
+        synchronized (this) {
+            mListeners.remove(l);
+        }
+    }
+
+    Handler handler() {
+        return mHandler;
+    }
+
+    @SuppressWarnings("unused")
+    private static void postEventFromNative(Object module_ref,
+                                            int what, int arg1, int arg2, Object obj) {
+        AudioPortEventHandler eventHandler =
+                (AudioPortEventHandler)((WeakReference)module_ref).get();
+        if (eventHandler == null) {
+            return;
+        }
+
+        if (eventHandler != null) {
+            Handler handler = eventHandler.handler();
+            if (handler != null) {
+                Message m = handler.obtainMessage(what, arg1, arg2, obj);
+                handler.sendMessage(m);
+            }
+        }
+    }
+
+}