dual-mode switching single/multiuser ServiceWatcher

This changelist revises LocationManager's previous multiuser system.

Location provider services that are not multiuser-aware continue to
run as before: ServiceWatcher binds to location provider services as
the current active user. When the device switches from one user to
another, ServiceWatcher unbinds from the old user's location provider
service and binds to the new user's instance.

Now, location provider services that are multiuser-aware or
user-agnostic can declare "serviceIsMultiuser" metadata in their
AndroidManifest.xml to prevent ServiceWatcher from performing this
switching. These services will run as singleton services and will be
expected to handle user switches on their own.

With this feature in, I was able to switch FusedLocationProvider to
run in multiuser mode, sharing the system_server process instead of
running in its own process. The NetworkLocationProvider is unchanged,
still running in singleuser mode, cheerfully oblivious to the
possibility that there might be any user on the device besides the
one it services.

Bug: 8028045
Change-Id: I1a5bd032918419bab6edb46c62ff8c6811170654

4 files changed, 31 insertions, 3 deletions

diff --git a/packages/FusedLocation/Android.mk b/packages/FusedLocation/Android.mk
index a81b9f1..318782f 100644
--- a/packages/FusedLocation/Android.mk
+++ b/packages/FusedLocation/Android.mk
@@ -23,6 +23,5 @@ LOCAL_JAVA_LIBRARIES := com.android.location.provider
 
 LOCAL_PACKAGE_NAME := FusedLocation
 LOCAL_CERTIFICATE := platform
-LOCAL_SDK_VERSION := current
 
 include $(BUILD_PACKAGE)
diff --git a/packages/FusedLocation/AndroidManifest.xml b/packages/FusedLocation/AndroidManifest.xml
index 779428e..6a4d4bf 100644
--- a/packages/FusedLocation/AndroidManifest.xml
+++ b/packages/FusedLocation/AndroidManifest.xml
@@ -18,14 +18,17 @@
 -->
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
         package="com.android.location.fused"
-        coreApp="true">
+        coreApp="true"
+        android:sharedUserId="android.uid.system">
 
     <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
     <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
     <uses-permission android:name="android.permission.INSTALL_LOCATION_PROVIDER" />
+    <uses-permission android:name="android.permission.INTERACT_ACROSS_USERS_FULL" />
 
     <application
-            android:label="@string/app_label">
+            android:label="@string/app_label"
+            android:process="system">
 
         <uses-library android:name="com.android.location.provider" />
 
@@ -39,6 +42,7 @@
                <action android:name="com.android.location.service.FusedLocationProvider" />
            </intent-filter>
            <meta-data android:name="serviceVersion" android:value="0" />
+           <meta-data android:name="serviceIsMultiuser" android:value="true" />
         </service>
     </application>
 </manifest>
diff --git a/packages/FusedLocation/src/com/android/location/fused/FusedLocationProvider.java b/packages/FusedLocation/src/com/android/location/fused/FusedLocationProvider.java
index 7918882..56feb47 100644
--- a/packages/FusedLocation/src/com/android/location/fused/FusedLocationProvider.java
+++ b/packages/FusedLocation/src/com/android/location/fused/FusedLocationProvider.java
@@ -24,13 +24,17 @@ import com.android.location.provider.LocationProviderBase;
 import com.android.location.provider.ProviderPropertiesUnbundled;
 import com.android.location.provider.ProviderRequestUnbundled;
 
+import android.content.BroadcastReceiver;
 import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
 import android.location.Criteria;
 import android.location.LocationProvider;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.Looper;
 import android.os.Message;
+import android.os.UserHandle;
 import android.os.WorkSource;
 
 public class FusedLocationProvider extends LocationProviderBase implements FusionEngine.Callback {
@@ -60,6 +64,19 @@ public class FusedLocationProvider extends LocationProviderBase implements Fusio
         super(TAG, PROPERTIES);
         mContext = context;
         mEngine = new FusionEngine(context, Looper.myLooper());
+
+        // listen for user change
+        IntentFilter intentFilter = new IntentFilter();
+        intentFilter.addAction(Intent.ACTION_USER_SWITCHED);
+        mContext.registerReceiverAsUser(new BroadcastReceiver() {
+            @Override
+            public void onReceive(Context context, Intent intent) {
+                String action = intent.getAction();
+                if (Intent.ACTION_USER_SWITCHED.equals(action)) {
+                    mEngine.switchUser();
+                }
+            }
+        }, UserHandle.ALL, intentFilter, null, mHandler);
     }
 
     /**
diff --git a/packages/FusedLocation/src/com/android/location/fused/FusionEngine.java b/packages/FusedLocation/src/com/android/location/fused/FusionEngine.java
index f909158..4ba6c34 100644
--- a/packages/FusedLocation/src/com/android/location/fused/FusionEngine.java
+++ b/packages/FusedLocation/src/com/android/location/fused/FusionEngine.java
@@ -300,4 +300,12 @@ public class FusionEngine implements LocationListener {
         s.append("    ").append(mStats.get(NETWORK)).append('\n');
         pw.append(s);
     }
+
+    /** Called on mLooper thread */
+    public void switchUser() {
+        // reset state to prevent location data leakage
+        mFusedLocation = null;
+        mGpsLocation = null;
+        mNetworkLocation = null;
+    }
 }