Migrate away from using ServiceManager

Create a wrapper class to access binder objects
published by statsd mainline module

Bug: 147923515
Test: atest com.google.android.statsd.gts.StatsdHostTestCases
Change-Id: I9ea3677d88c790c856e4e89318ae2ce67ac7df1e

7 files changed, 236 insertions, 10 deletions

diff --git a/apex/statsd/framework/java/android/app/StatsManager.java b/apex/statsd/framework/java/android/app/StatsManager.java
index 0ea05d8f683c..ad1ac95d667c 100644
--- a/apex/statsd/framework/java/android/app/StatsManager.java
+++ b/apex/statsd/framework/java/android/app/StatsManager.java
@@ -30,7 +30,7 @@ import android.os.IPullAtomResultReceiver;
 import android.os.IStatsManagerService;
 import android.os.IStatsd;
 import android.os.RemoteException;
-import android.os.ServiceManager;
+import android.os.StatsFrameworkInitializer;
 import android.util.AndroidException;
 import android.util.Slog;
 import android.util.StatsEvent;
@@ -702,7 +702,10 @@ public final class StatsManager {
             return mStatsManagerService;
         }
         mStatsManagerService = IStatsManagerService.Stub.asInterface(
-                ServiceManager.getService(Context.STATS_MANAGER_SERVICE));
+                StatsFrameworkInitializer
+                .getStatsServiceManager()
+                .getStatsManagerServiceRegisterer()
+                .get());
         return mStatsManagerService;
     }
 
diff --git a/apex/statsd/framework/java/android/os/StatsFrameworkInitializer.java b/apex/statsd/framework/java/android/os/StatsFrameworkInitializer.java
new file mode 100644
index 000000000000..3d955336b45c
--- /dev/null
+++ b/apex/statsd/framework/java/android/os/StatsFrameworkInitializer.java
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2020 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;
+
+import android.annotation.NonNull;
+import android.annotation.SystemApi;
+import android.app.StatsManager;
+import android.app.SystemServiceRegistry;
+import android.content.Context;
+
+/**
+ * Class for performing registration for all stats services
+ *
+ * TODO(b/148225705) Change to @SystemApi(client=MODULE_LIBRARIES) when the build system is ready.
+ * @hide
+ */
+@SystemApi
+public class StatsFrameworkInitializer {
+    private StatsFrameworkInitializer() {
+    }
+
+    private static volatile StatsServiceManager sStatsServiceManager;
+
+    /**
+     * Sets an instance of {@link StatsServiceManager} that allows
+     * the statsd mainline module to register/obtain stats binder services. This is called
+     * by the platform during the system initialization.
+     *
+     * @param statsServiceManager instance of {@link StatsServiceManager} that allows
+     * the statsd mainline module to register/obtain statsd binder services.
+     */
+    public static void setStatsServiceManager(
+            @NonNull StatsServiceManager statsServiceManager) {
+        if (sStatsServiceManager != null) {
+            throw new IllegalStateException("setStatsServiceManager called twice!");
+        }
+
+        if (statsServiceManager == null) {
+            throw new NullPointerException("statsServiceManager is null");
+        }
+
+        sStatsServiceManager = statsServiceManager;
+    }
+
+    /** @hide */
+    public static StatsServiceManager getStatsServiceManager() {
+        return sStatsServiceManager;
+    }
+
+    /**
+     * Called by {@link SystemServiceRegistry}'s static initializer and registers all statsd
+     * services to {@link Context}, so that {@link Context#getSystemService} can return them.
+     *
+     * @throws IllegalStateException if this is called from anywhere besides
+     * {@link SystemServiceRegistry}
+     */
+    public static void registerServiceWrappers() {
+        SystemServiceRegistry.registerContextAwareService(
+                Context.STATS_MANAGER,
+                StatsManager.class,
+                context -> new StatsManager(context)
+        );
+    }
+}
diff --git a/apex/statsd/service/java/com/android/server/stats/StatsCompanionService.java b/apex/statsd/service/java/com/android/server/stats/StatsCompanionService.java
index bcbb5a1407f6..4c8790f47bb6 100644
--- a/apex/statsd/service/java/com/android/server/stats/StatsCompanionService.java
+++ b/apex/statsd/service/java/com/android/server/stats/StatsCompanionService.java
@@ -85,6 +85,7 @@ import android.os.ParcelFileDescriptor;
 import android.os.Parcelable;
 import android.os.RemoteException;
 import android.os.ServiceManager;
+import android.os.StatsFrameworkInitializer;
 import android.os.StatFs;
 import android.os.StatsLogEventWrapper;
 import android.os.SynchronousResultReceiver;
@@ -750,7 +751,10 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {
      * sStatsd with a null check.
      */
     private static IStatsd fetchStatsdService() {
-        return IStatsd.Stub.asInterface(ServiceManager.getService("stats"));
+        return IStatsd.Stub.asInterface(StatsFrameworkInitializer
+            .getStatsServiceManager()
+            .getStatsdServiceRegisterer()
+            .get());
     }
 
     /**
diff --git a/api/system-current.txt b/api/system-current.txt
index 327f64268f8f..b694402882f2 100755
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -8566,6 +8566,26 @@ package android.os {
     field public static final int TUPLE_VALUE_TYPE = 7; // 0x7
   }
 
+  public class StatsFrameworkInitializer {
+    method public static void registerServiceWrappers();
+    method public static void setStatsServiceManager(@NonNull android.os.StatsServiceManager);
+  }
+
+  public class StatsServiceManager {
+    method @NonNull public android.os.StatsServiceManager.ServiceRegisterer getStatsCompanionServiceRegisterer();
+    method @NonNull public android.os.StatsServiceManager.ServiceRegisterer getStatsManagerServiceRegisterer();
+    method @NonNull public android.os.StatsServiceManager.ServiceRegisterer getStatsdServiceRegisterer();
+  }
+
+  public static class StatsServiceManager.ServiceNotFoundException extends java.lang.Exception {
+    ctor public StatsServiceManager.ServiceNotFoundException(@NonNull String);
+  }
+
+  public static final class StatsServiceManager.ServiceRegisterer {
+    method @Nullable public android.os.IBinder get();
+    method @Nullable public android.os.IBinder getOrThrow() throws android.os.StatsServiceManager.ServiceNotFoundException;
+  }
+
   public class SystemConfigManager {
     method @NonNull @RequiresPermission(android.Manifest.permission.READ_CARRIER_APP_INFO) public java.util.Set<java.lang.String> getDisabledUntilUsedPreinstalledCarrierApps();
     method @NonNull @RequiresPermission(android.Manifest.permission.READ_CARRIER_APP_INFO) public java.util.Map<java.lang.String,java.util.List<java.lang.String>> getDisabledUntilUsedPreinstalledCarrierAssociatedApps();
diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index b82a67556fc0..57ba1819e9c0 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -111,6 +111,8 @@ import android.os.Process;
 import android.os.RemoteCallback;
 import android.os.RemoteException;
 import android.os.ServiceManager;
+import android.os.StatsFrameworkInitializer;
+import android.os.StatsServiceManager;
 import android.os.StrictMode;
 import android.os.SystemClock;
 import android.os.SystemProperties;
@@ -7514,6 +7516,7 @@ public final class ActivityThread extends ClientTransactionHandler {
      */
     public static void initializeMainlineModules() {
         TelephonyFrameworkInitializer.setTelephonyServiceManager(new TelephonyServiceManager());
+        StatsFrameworkInitializer.setStatsServiceManager(new StatsServiceManager());
     }
 
     private void purgePendingResources() {
diff --git a/core/java/android/app/SystemServiceRegistry.java b/core/java/android/app/SystemServiceRegistry.java
index c1e535643ddf..e0c39c2e6648 100644
--- a/core/java/android/app/SystemServiceRegistry.java
+++ b/core/java/android/app/SystemServiceRegistry.java
@@ -148,6 +148,7 @@ import android.os.RecoverySystem;
 import android.os.RemoteException;
 import android.os.ServiceManager;
 import android.os.ServiceManager.ServiceNotFoundException;
+import android.os.StatsFrameworkInitializer;
 import android.os.SystemConfigManager;
 import android.os.SystemUpdateManager;
 import android.os.SystemVibrator;
@@ -587,13 +588,6 @@ public final class SystemServiceRegistry {
                         return SensorPrivacyManager.getInstance(ctx);
                     }});
 
-        registerService(Context.STATS_MANAGER, StatsManager.class,
-                new CachedServiceFetcher<StatsManager>() {
-            @Override
-            public StatsManager createService(ContextImpl ctx) {
-                return new StatsManager(ctx.getOuterContext());
-            }});
-
         registerService(Context.STATUS_BAR_SERVICE, StatusBarManager.class,
                 new CachedServiceFetcher<StatusBarManager>() {
             @Override
@@ -1306,6 +1300,7 @@ public final class SystemServiceRegistry {
             TelephonyFrameworkInitializer.registerServiceWrappers();
             AppSearchManagerFrameworkInitializer.initialize();
             WifiFrameworkInitializer.registerServiceWrappers();
+            StatsFrameworkInitializer.registerServiceWrappers();
         } finally {
             // If any of the above code throws, we're in a pretty bad shape and the process
             // will likely crash, but we'll reset it just in case there's an exception handler...
diff --git a/core/java/android/os/StatsServiceManager.java b/core/java/android/os/StatsServiceManager.java
new file mode 100644
index 000000000000..d032e98da00c
--- /dev/null
+++ b/core/java/android/os/StatsServiceManager.java
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2020 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;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+
+/**
+ * Provides a way to register and obtain the system service binder objects managed by the stats
+ * service.
+ *
+ * <p> Only the statsd mainline module will be able to access an instance of this class.
+ *
+ * TODO(b/148225705) Change to @SystemApi(client=MODULE_LIBRARIES) when the build system is ready.
+ * @hide
+ */
+@SystemApi
+public class StatsServiceManager {
+    /**
+     * @hide
+     */
+    public StatsServiceManager() {}
+
+    /**
+     * A class that exposes the methods to register and obtain each system service.
+     */
+    public static final class ServiceRegisterer {
+        private final String mServiceName;
+
+        /**
+         * @hide
+         */
+        public ServiceRegisterer(String serviceName) {
+            mServiceName = serviceName;
+        }
+
+        /**
+         * Get the system server binding object for StatsManagerService.
+         *
+         * <p> This blocks until the service instance is ready.
+         * or a timeout happens, in which case it returns null.
+         */
+        @Nullable
+        public IBinder get() {
+            return ServiceManager.getService(mServiceName);
+        }
+
+        /**
+         * Get the system server binding object for a service.
+         *
+         * <p>This blocks until the service instance is ready,
+         * or a timeout happens, in which case it throws {@link ServiceNotFoundException}.
+         */
+        @Nullable
+        public IBinder getOrThrow() throws ServiceNotFoundException {
+            try {
+                return ServiceManager.getServiceOrThrow(mServiceName);
+            } catch (ServiceManager.ServiceNotFoundException e) {
+                throw new ServiceNotFoundException(mServiceName);
+            }
+        }
+
+        /**
+         * Get the system server binding object for a service. If the specified service is
+         * not available, it returns null.
+         */
+        @Nullable
+        private IBinder tryGet() {
+            return ServiceManager.checkService(mServiceName);
+        }
+    }
+
+    /**
+     * See {@link ServiceRegisterer#getOrThrow()}
+     */
+    public static class ServiceNotFoundException extends ServiceManager.ServiceNotFoundException {
+        /**
+         * Constructor
+         *
+         * @param name the name of the binder service that cannot be found.
+         */
+        public ServiceNotFoundException(@NonNull String name) {
+            super(name);
+        }
+    }
+
+    /**
+     * Returns {@link ServiceRegisterer} for the "statscompanion" service.
+     */
+    @NonNull
+    public ServiceRegisterer getStatsCompanionServiceRegisterer() {
+        return new ServiceRegisterer("statscompanion");
+    }
+
+    /**
+     * Returns {@link ServiceRegisterer} for the "statsmanager" service.
+     */
+    @NonNull
+    public ServiceRegisterer getStatsManagerServiceRegisterer() {
+        return new ServiceRegisterer("statsmanager");
+    }
+
+    /**
+     * Returns {@link ServiceRegisterer} for the "statsd" service.
+     */
+    @NonNull
+    public ServiceRegisterer getStatsdServiceRegisterer() {
+        return new ServiceRegisterer("stats");
+    }
+}