From f2f7a74feebd2417dd203db8e7ed7946cfeee109 Mon Sep 17 00:00:00 2001
From: Yasin Kilicdere <tyk@google.com>
Date: Thu, 3 Nov 2022 15:46:00 +0000
Subject: [PATCH] Add timeout fallback to UserController dismissKeyguard on
 user switch.

After a user switch, keyguard is dismissed if there is no password
for the target user. Then after the dismissal of the keyguard,
unfreezing the screen and calling UserSwitchObservers
onUserSwitchComplete is done. In case dismissKeyguard's callbacks
are not called, user switch can not be complete. This CL makes sure
user switch flow moves on even when the keyguard dismissal fails.

Bug: 256576977
Test: atest FrameworksServicesTests:UserControllerTest
Change-Id: I608a43de4d379a26ef66737c1bece7508d476b2e
---
 .../com/android/server/am/UserController.java | 23 ++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/services/core/java/com/android/server/am/UserController.java b/services/core/java/com/android/server/am/UserController.java
index af559808d880f..8049a3adeb5fe 100644
--- a/services/core/java/com/android/server/am/UserController.java
+++ b/services/core/java/com/android/server/am/UserController.java
@@ -134,6 +134,7 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Objects;
 import java.util.concurrent.ThreadLocalRandom;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 
 /**
@@ -199,6 +200,14 @@ class UserController implements Handler.Callback {
      */
     private static final int USER_SWITCH_CALLBACKS_TIMEOUT_MS = 5 * 1000;
 
+    /**
+     * Amount of time waited for {@link WindowManagerService#dismissKeyguard} callbacks to be
+     * called after dismissing the keyguard.
+     * Otherwise, we should move on to unfreeze the screen {@link #unfreezeScreen}
+     * and report user switch is complete {@link #REPORT_USER_SWITCH_COMPLETE_MSG}.
+     */
+    private static final int DISMISS_KEYGUARD_TIMEOUT_MS = 2 * 1000;
+
     /**
      * Time after last scheduleOnUserCompletedEvent() call at which USER_COMPLETED_EVENT_MSG will be
      * scheduled (although it may fire sooner instead).
@@ -3653,20 +3662,28 @@ class UserController implements Handler.Callback {
         }
 
         protected void dismissKeyguard(Runnable runnable, String reason) {
+            final AtomicBoolean isFirst = new AtomicBoolean(true);
+            final Runnable runOnce = () -> {
+                if (isFirst.getAndSet(false)) {
+                    runnable.run();
+                }
+            };
+
+            mHandler.postDelayed(runOnce, DISMISS_KEYGUARD_TIMEOUT_MS);
             getWindowManager().dismissKeyguard(new IKeyguardDismissCallback.Stub() {
                 @Override
                 public void onDismissError() throws RemoteException {
-                    mHandler.post(runnable);
+                    mHandler.post(runOnce);
                 }
 
                 @Override
                 public void onDismissSucceeded() throws RemoteException {
-                    mHandler.post(runnable);
+                    mHandler.post(runOnce);
                 }
 
                 @Override
                 public void onDismissCancelled() throws RemoteException {
-                    mHandler.post(runnable);
+                    mHandler.post(runOnce);
                 }
             }, reason);
         }