From 907dcf8fb867b6463e1cb8328e196dbfb0eb60c1 Mon Sep 17 00:00:00 2001
From: Hai Zhang <zhanghai@google.com>
Date: Wed, 20 Jan 2021 04:27:15 -0800
Subject: [PATCH] Fix granting default roles timeout.

The RoleControllerManager takes a Handler for service connection
callbacks, and that Handler has to be a thread other than the main
thread inside system server because we need to block the main thread
before necessary permissions are granted via role.

However, since a recent change that exposed RoleControllerManager APIs
on RoleManager instead to hide this implementation detail from API, we
are creating the RoleControllerManager instance upon RoleManager
creation and implicitly initializing it with the main thread
Handler. This may result in the RoleControllerManager getting the main
thread handler instead of the desired foreground thread handler if
someone else in the system server created RoleManager first, and that
would create a deadlock when we block the main thread.

So revert to the original timing for RoleControllerManager creation by
creating it lazily, so that it gets the correct handler as the only
user of it inside system server is RoleManagerService, and other
services who only need the RoleManager won't affect
RoleControllerManager.

Fixes: 177251364
Test: manual
Change-Id: I649a23fa3b88fbd9120b3de408eee8a590d50a17
---
 core/java/android/app/role/RoleManager.java | 21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/core/java/android/app/role/RoleManager.java b/core/java/android/app/role/RoleManager.java
index 0fcf44d2dda63..3788257bcf171 100644
--- a/core/java/android/app/role/RoleManager.java
+++ b/core/java/android/app/role/RoleManager.java
@@ -174,8 +174,10 @@ public final class RoleManager {
     @NonNull
     private final Object mListenersLock = new Object();
 
-    @NonNull
-    private final RoleControllerManager mRoleControllerManager;
+    @GuardedBy("mRoleControllerManagerLock")
+    @Nullable
+    private RoleControllerManager mRoleControllerManager;
+    private final Object mRoleControllerManagerLock = new Object();
 
     /**
      * @hide
@@ -184,7 +186,6 @@ public final class RoleManager {
         mContext = context;
         mService = IRoleManager.Stub.asInterface(ServiceManager.getServiceOrThrow(
                 Context.ROLE_SERVICE));
-        mRoleControllerManager = new RoleControllerManager(context);
     }
 
     /**
@@ -693,7 +694,7 @@ public final class RoleManager {
     @TestApi
     public void isRoleVisible(@NonNull String roleName,
             @NonNull @CallbackExecutor Executor executor, @NonNull Consumer<Boolean> callback) {
-        mRoleControllerManager.isRoleVisible(roleName, executor, callback);
+        getRoleControllerManager().isRoleVisible(roleName, executor, callback);
     }
 
     /**
@@ -714,10 +715,20 @@ public final class RoleManager {
     @TestApi
     public void isApplicationVisibleForRole(@NonNull String roleName, @NonNull String packageName,
             @NonNull @CallbackExecutor Executor executor, @NonNull Consumer<Boolean> callback) {
-        mRoleControllerManager.isApplicationVisibleForRole(roleName, packageName, executor,
+        getRoleControllerManager().isApplicationVisibleForRole(roleName, packageName, executor,
                 callback);
     }
 
+    @NonNull
+    private RoleControllerManager getRoleControllerManager() {
+        synchronized (mRoleControllerManagerLock) {
+            if (mRoleControllerManager == null) {
+                mRoleControllerManager = new RoleControllerManager(mContext);
+            }
+            return mRoleControllerManager;
+        }
+    }
+
     private static class OnRoleHoldersChangedListenerDelegate
             extends IOnRoleHoldersChangedListener.Stub {