Add a native aidl API.

Introduce a platform_compat_native service that just calls the
platform_compat service.
The new service is needed as it needs a slightly different (more
limited, no ApplicationInfo in cpp) aidl API, and a class can only
extend one stub.

Test: Call the service from dumpsys.cpp (http://aosp/1142055)
Bug: 138275545
Change-Id: Ic46cc34b4c1dd4ebc6bcc996fb3f8503607214ac

Android.bp

@@ -213,6 +213,9 @@ filegroup {
         ":PacProcessor-aidl-sources",
         ":ProxyHandler-aidl-sources",
 
+        // AIDL from frameworks/base/native/
+        ":platform-compat-native-aidl",
+
         // AIDL sources from external directories
         ":dumpstate_aidl",
         ":framework_native_aidl",

core/java/android/content/Context.java

@@ -74,6 +74,7 @@ import android.view.contentcapture.ContentCaptureManager.ContentCaptureClient;
 import android.view.textclassifier.TextClassificationManager;
 
 import com.android.internal.compat.IPlatformCompat;
+import com.android.internal.compat.IPlatformCompatNative;
 
 import java.io.File;
 import java.io.FileInputStream;
@@ -3243,6 +3244,7 @@ public abstract class Context {
             //@hide ROLE_CONTROLLER_SERVICE,
             CAMERA_SERVICE,
             //@hide: PLATFORM_COMPAT_SERVICE,
+            //@hide: PLATFORM_COMPAT_NATIVE_SERVICE,
             PRINT_SERVICE,
             CONSUMER_IR_SERVICE,
             //@hide: TRUST_SERVICE,
@@ -4619,6 +4621,14 @@ public abstract class Context {
      */
     public static final String PLATFORM_COMPAT_SERVICE = "platform_compat";
 
+    /**
+     * Use with {@link android.os.ServiceManager.getService()} to retrieve a
+     * {@link IPlatformCompatNative} IBinder for native code communicating with the platform compat
+     * service.
+     * @hide
+     */
+    public static final String PLATFORM_COMPAT_NATIVE_SERVICE = "platform_compat_native";
+
     /**
      * Service to capture a bugreport.
      * @see #getSystemService(String)

native/android/Android.bp

@@ -110,3 +110,36 @@ llndk_library {
     symbol_file: "libandroid_net.map.txt",
     unversioned: true,
 }
+
+
+// Aidl library for platform compat.
+cc_library_shared {
+    name: "lib-platform-compat-native-api",
+    cflags: [
+            "-Wall",
+            "-Werror",
+            "-Wno-missing-field-initializers",
+            "-Wno-unused-variable",
+            "-Wunused-parameter",
+        ],
+    shared_libs: [
+        "libbinder",
+         "libutils",
+    ],
+    aidl: {
+        local_include_dirs: ["aidl"],
+        export_aidl_headers: true,
+    },
+    srcs: [
+         ":platform-compat-native-aidl",
+    ],
+    export_include_dirs: ["aidl"],
+}
+
+filegroup {
+    name: "platform-compat-native-aidl",
+    srcs: [
+        "aidl/com/android/internal/compat/IPlatformCompatNative.aidl",
+    ],
+    path: "aidl",
+}
\ No newline at end of file

native/android/aidl/com/android/internal/compat/IPlatformCompatNative.aidl

+/*
+ * Copyright (C) 2019 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.internal.compat;
+
+/**
+ * Platform native private API for talking with the PlatformCompat service.
+ *
+ * <p> Should be used for gating and logging from non-app processes running cpp code.
+ * For app processes please use android.compat.Compatibility API.
+ *
+ * {@hide}
+ */
+interface IPlatformCompatNative
+{
+    /**
+     * Reports that a compatibility change is affecting an app process now.
+     *
+     * <p>Note: for changes that are gated using {@link #isChangeEnabled(long, String)},
+     * you do not need to call this API directly. The change will be reported for you.
+     *
+     * @param changeId    The ID of the compatibility change taking effect.
+     * @param packageName The package name of the app in question.
+     */
+     void reportChangeByPackageName(long changeId, @utf8InCpp String packageName);
+
+    /**
+     * Reports that a compatibility change is affecting an app process now.
+     *
+     * <p>Note: for changes that are gated using {@link #isChangeEnabled(long, int)},
+     * you do not need to call this API directly. The change will be reported for you.
+     *
+     * @param changeId The ID of the compatibility change taking effect.
+     * @param uid      The UID of the app in question.
+     */
+    void reportChangeByUid(long changeId, int uid);
+
+    /**
+     * Query if a given compatibility change is enabled for an app process. This method should
+     * be called when implementing functionality on behalf of the affected app.
+     *
+     * <p>Returns {@code true} if there is no installed package by the provided package name.
+     *
+     * <p>If this method returns {@code true}, the calling code should implement the compatibility
+     * change, resulting in differing behaviour compared to earlier releases. If this method
+     * returns
+     * {@code false}, the calling code should behave as it did in earlier releases.
+     *
+     * <p>It will also report the change as {@link #reportChange(long, String)} would, so there is
+     * no need to call that method directly.
+     *
+     * @param changeId    The ID of the compatibility change in question.
+     * @param packageName The package name of the app in question.
+     * @return {@code true} if the change is enabled for the current app.
+     */
+    boolean isChangeEnabledByPackageName(long changeId, @utf8InCpp String packageName);
+
+    /**
+     * Query if a given compatibility change is enabled for an app process. This method should
+     * be called when implementing functionality on behalf of the affected app.
+     *
+     * <p> Returns {@code true} if there are no installed packages for the required UID, or if the
+     * change is enabled for ALL of the installed packages associated with the provided UID. Please
+     * use a more specific API if you want a different behaviour for multi-package UIDs.
+     *
+     * <p>If this method returns {@code true}, the calling code should implement the compatibility
+     * change, resulting in differing behaviour compared to earlier releases. If this method
+     * returns {@code false}, the calling code should behave as it did in earlier releases.
+     *
+     * <p>It will also report the change as {@link #reportChange(long, int)} would, so there is
+     * no need to call that method directly.
+     *
+     * @param changeId The ID of the compatibility change in question.
+     * @param uid      The UID of the app in question.
+     * @return {@code true} if the change is enabled for the current app.
+     */
+    boolean isChangeEnabledByUid(long changeId, int uid);
+}
\ No newline at end of file

services/core/java/com/android/server/compat/PlatformCompatNative.java

+/*
+ * Copyright (C) 2019 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.compat;
+
+import com.android.internal.compat.IPlatformCompatNative;
+
+/**
+ * @hide
+ */
+public class PlatformCompatNative extends IPlatformCompatNative.Stub {
+    private final PlatformCompat mPlatformCompat;
+
+    public PlatformCompatNative(PlatformCompat platformCompat) {
+        mPlatformCompat = platformCompat;
+    }
+
+    @Override
+    public void reportChangeByPackageName(long changeId, String packageName) {
+        mPlatformCompat.reportChangeByPackageName(changeId, packageName);
+    }
+
+    @Override
+    public void reportChangeByUid(long changeId, int uid) {
+        mPlatformCompat.reportChangeByUid(changeId, uid);
+    }
+
+    @Override
+    public boolean isChangeEnabledByPackageName(long changeId, String packageName) {
+        return mPlatformCompat.isChangeEnabledByPackageName(changeId, packageName);
+    }
+
+    @Override
+    public boolean isChangeEnabledByUid(long changeId, int uid) {
+        return mPlatformCompat.isChangeEnabledByUid(changeId, uid);
+    }
+}

services/java/com/android/server/SystemServer.java

@@ -90,6 +90,7 @@ import com.android.server.broadcastradio.BroadcastRadioService;
 import com.android.server.camera.CameraServiceProxy;
 import com.android.server.clipboard.ClipboardService;
 import com.android.server.compat.PlatformCompat;
+import com.android.server.compat.PlatformCompatNative;
 import com.android.server.connectivity.IpConnectivityMetrics;
 import com.android.server.contentcapture.ContentCaptureManagerInternal;
 import com.android.server.coverage.CoverageService;
@@ -641,8 +642,10 @@ public final class SystemServer {
         // Platform compat service is used by ActivityManagerService, PackageManagerService, and
         // possibly others in the future. b/135010838.
         t.traceBegin("PlatformCompat");
-        ServiceManager.addService(Context.PLATFORM_COMPAT_SERVICE,
-                new PlatformCompat(mSystemContext));
+        PlatformCompat platformCompat = new PlatformCompat(mSystemContext);
+        ServiceManager.addService(Context.PLATFORM_COMPAT_SERVICE, platformCompat);
+        ServiceManager.addService(Context.PLATFORM_COMPAT_NATIVE_SERVICE,
+                new PlatformCompatNative(platformCompat));
         t.traceEnd();
 
         // Wait for installd to finish starting up so that it has a chance to