RESTRICT AUTOMERGE Only update native InputApplicationHandle once

This makes sure the write operation (NativeInputApplicationHandle
::updateInfo) is always called from window manager side once when
calling SurfaceControl.Transaction#setInputWindowInfo or
InputManagerService#setFocusedApplication. If the info of input
application handle is changed, a new instance will be created.
That avoids the race condition of reading the fields of the same
InputApplicationInfo instance from input dispatcher.

Bug: 171857140
Bug: 161334769
Test: WindowInputTests

Change-Id: I70de9835c7699fe6f56fc3655b0fee5c317ecc3a

core/java/android/view/InputApplicationHandle.java

@@ -16,6 +16,7 @@
 
 package android.view;
 
+import android.annotation.NonNull;
 import android.os.IBinder;
 
 /**
@@ -31,17 +32,20 @@ public final class InputApplicationHandle {
     private long ptr;
 
     // Application name.
-    public String name;
+    public final @NonNull String name;
 
     // Dispatching timeout.
-    public long dispatchingTimeoutNanos;
+    public final long dispatchingTimeoutNanos;
 
     public final IBinder token;
 
     private native void nativeDispose();
 
-    public InputApplicationHandle(IBinder token) {
+    public InputApplicationHandle(@NonNull IBinder token, @NonNull String name,
+            long dispatchingTimeoutNanos) {
         this.token = token;
+        this.name = name;
+        this.dispatchingTimeoutNanos = dispatchingTimeoutNanos;
     }
 
     public InputApplicationHandle(InputApplicationHandle handle) {

core/java/android/view/InputWindowHandle.java

@@ -36,7 +36,7 @@ public final class InputWindowHandle {
     private long ptr;
 
     // The input application handle.
-    public final InputApplicationHandle inputApplicationHandle;
+    public InputApplicationHandle inputApplicationHandle;
 
     // The token associates input data with a window and its input channel. The client input
     // channel and the server input channel will both contain this token.

core/jni/android_hardware_input_InputApplicationHandle.cpp

@@ -58,6 +58,11 @@ bool NativeInputApplicationHandle::updateInfo() {
     if (!obj) {
         return false;
     }
+    if (mInfo.token.get() != nullptr) {
+        // The java fields are immutable, so it doesn't need to update again.
+        env->DeleteLocalRef(obj);
+        return true;
+    }
 
     mInfo.name = getStringField(env, obj, gInputApplicationHandleClassInfo.name, "<null>");
 

services/core/java/com/android/server/wm/ActivityRecord.java

@@ -416,7 +416,7 @@ final class ActivityRecord extends WindowToken implements WindowManagerService.A
     // mOccludesParent field.
     final boolean hasWallpaper;
     // Input application handle used by the input dispatcher.
-    final InputApplicationHandle mInputApplicationHandle;
+    private InputApplicationHandle mInputApplicationHandle;
 
     final int launchedFromPid; // always the pid who started the activity.
     final int launchedFromUid; // always the uid who started the activity.
@@ -1501,7 +1501,6 @@ final class ActivityRecord extends WindowToken implements WindowManagerService.A
         info = aInfo;
         mUserId = UserHandle.getUserId(info.applicationInfo.uid);
         packageName = info.applicationInfo.packageName;
-        mInputApplicationHandle = new InputApplicationHandle(appToken);
         intent = _intent;
 
         // If the class name in the intent doesn't match that of the target, this is probably an
@@ -1685,6 +1684,21 @@ final class ActivityRecord extends WindowToken implements WindowManagerService.A
         return lockTaskLaunchMode;
     }
 
+    @NonNull InputApplicationHandle getInputApplicationHandle(boolean update) {
+        if (mInputApplicationHandle == null) {
+            mInputApplicationHandle = new InputApplicationHandle(appToken, toString(),
+                    mInputDispatchingTimeoutNanos);
+        } else if (update) {
+            final String name = toString();
+            if (mInputDispatchingTimeoutNanos != mInputApplicationHandle.dispatchingTimeoutNanos
+                    || !name.equals(mInputApplicationHandle.name)) {
+                mInputApplicationHandle = new InputApplicationHandle(appToken, name,
+                        mInputDispatchingTimeoutNanos);
+            }
+        }
+        return mInputApplicationHandle;
+    }
+
     @Override
     ActivityRecord asActivityRecord() {
         // I am an activity record!

services/core/java/com/android/server/wm/DragState.java

@@ -269,10 +269,8 @@ class DragState {
             mInputEventReceiver = new DragInputEventReceiver(mClientChannel,
                     mService.mH.getLooper(), mDragDropController);
 
-            mDragApplicationHandle = new InputApplicationHandle(new Binder());
+            mDragApplicationHandle = new InputApplicationHandle(new Binder(), "drag",
-            mDragApplicationHandle.name = "drag";
+                    WindowManagerService.DEFAULT_INPUT_DISPATCHING_TIMEOUT_NANOS);
-            mDragApplicationHandle.dispatchingTimeoutNanos =
-                    WindowManagerService.DEFAULT_INPUT_DISPATCHING_TIMEOUT_NANOS;
 
             mDragWindowHandle = new InputWindowHandle(mDragApplicationHandle,
                     display.getDisplayId());

services/core/java/com/android/server/wm/InputConsumerImpl.java

@@ -67,10 +67,8 @@ class InputConsumerImpl implements IBinder.DeathRecipient {
         }
         mService.mInputManager.registerInputChannel(mServerChannel);
 
-        mApplicationHandle = new InputApplicationHandle(new Binder());
+        mApplicationHandle = new InputApplicationHandle(new Binder(), name,
-        mApplicationHandle.name = name;
+                WindowManagerService.DEFAULT_INPUT_DISPATCHING_TIMEOUT_NANOS);
-        mApplicationHandle.dispatchingTimeoutNanos =
-                WindowManagerService.DEFAULT_INPUT_DISPATCHING_TIMEOUT_NANOS;
 
         mWindowHandle = new InputWindowHandle(mApplicationHandle, displayId);
         mWindowHandle.name = name;

services/core/java/com/android/server/wm/InputMonitor.java

@@ -258,6 +258,8 @@ final class InputMonitor {
             final boolean hasFocus, final boolean hasWallpaper) {
         // Add a window to our list of input windows.
         inputWindowHandle.name = child.toString();
+        inputWindowHandle.inputApplicationHandle = child.mActivityRecord != null
+                ? child.mActivityRecord.getInputApplicationHandle(false /* update */) : null;
         flags = child.getSurfaceTouchableRegion(inputWindowHandle, flags);
         inputWindowHandle.layoutParamsFlags = flags;
         inputWindowHandle.layoutParamsType = type;
@@ -376,15 +378,8 @@ final class InputMonitor {
 
     public void setFocusedAppLw(ActivityRecord newApp) {
         // Focused app has changed.
-        if (newApp == null) {
+        mService.mInputManager.setFocusedApplication(mDisplayId,
-            mService.mInputManager.setFocusedApplication(mDisplayId, null);
+                newApp != null ? newApp.getInputApplicationHandle(true /* update */) : null);
-        } else {
-            final InputApplicationHandle handle = newApp.mInputApplicationHandle;
-            handle.name = newApp.toString();
-            handle.dispatchingTimeoutNanos = newApp.mInputDispatchingTimeoutNanos;
-
-            mService.mInputManager.setFocusedApplication(mDisplayId, handle);
-        }
     }
 
     public void pauseDispatchingLw(WindowToken window) {

services/core/java/com/android/server/wm/TaskPositioner.java

@@ -228,10 +228,8 @@ class TaskPositioner implements IBinder.DeathRecipient {
                 mClientChannel, mService.mAnimationHandler.getLooper(),
                 mService.mAnimator.getChoreographer());
 
-        mDragApplicationHandle = new InputApplicationHandle(new Binder());
+        mDragApplicationHandle = new InputApplicationHandle(new Binder(), TAG,
-        mDragApplicationHandle.name = TAG;
+                WindowManagerService.DEFAULT_INPUT_DISPATCHING_TIMEOUT_NANOS);
-        mDragApplicationHandle.dispatchingTimeoutNanos =
-                WindowManagerService.DEFAULT_INPUT_DISPATCHING_TIMEOUT_NANOS;
 
         mDragWindowHandle = new InputWindowHandle(mDragApplicationHandle,
                 displayContent.getDisplayId());

services/core/java/com/android/server/wm/WindowState.java

@@ -942,7 +942,8 @@ class WindowState extends WindowContainer<WindowState> implements WindowManagerP
         mLastRequestedHeight = 0;
         mLayer = 0;
         mInputWindowHandle = new InputWindowHandle(
-                mActivityRecord != null ? mActivityRecord.mInputApplicationHandle : null,
+                mActivityRecord != null ?
+                        mActivityRecord.getInputApplicationHandle(false /* update */) : null,
                     getDisplayId());
 
         // Make sure we initial all fields before adding to parentWindow, to prevent exception