Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 291aea22 authored by Robert Carr's avatar Robert Carr
Browse files

Toast timeout: Just strip FLAG_KEEP_SCREEN_ON 

We added the toast timeout to fix b/21693547. Where the client
leaks non visible toasts which end up keeping the screen on.
Simply removing the toast windows as we were doing previously,
isn't very good though. If the timeout fires when an app could
still use the toast (e.g. due to long pause under debugger),
the app could crash. It's not obvious how (if even possible
without API semantic/guarantee change) to prevent this issue
from the client side. Furthermore, #33 at b/21693457 implies that
we need to respect FLAG_KEEP_SCREEN_ON even for windows that
never submitted a buffer. With time constraints as they are,
the only solution I can think of that solves both without
chance of regression is just stripping FLAG_KEEP_SCREEN_ON when the
timeout fires.

Bug: 29105388
Change-Id: Ic2df897f86acf814ea3d4f911a0532d65af0c19f
parent e4b1fb94

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

+13 −6
Original line number Diff line number Diff line
@@ -177,6 +177,7 @@ import static android.view.WindowManager.DOCKED_TOP; 
import static android.view.WindowManager.LayoutParams.FIRST_APPLICATION_WINDOW;

import static android.view.WindowManager.LayoutParams.FIRST_SUB_WINDOW;

import static android.view.WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM;

import static android.view.WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON;

import static android.view.WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;

import static android.view.WindowManager.LayoutParams.FLAG_SECURE;

import static android.view.WindowManager.LayoutParams.FLAG_SHOW_WALLPAPER;
@@ -8614,12 +8615,18 @@ public class WindowManagerService extends IWindowManager.Stub 
                case WINDOW_REMOVE_TIMEOUT: {

                    final WindowState window = (WindowState) msg.obj;

                    synchronized(mWindowMap) {

                        // It's counterintuitive that we check that "mWindowRemovalAllowed"

                        // is false. But in fact if it's true, it means a remove has already

                        // been requested and we better just not do anything.

                        if (!window.mRemoved && !window.mWindowRemovalAllowed) {

                            removeWindowLocked(window);

                        }

                        // TODO: This is all about fixing b/21693547

                        // where partially initialized Toasts get stuck

                        // around and keep the screen on. We'd like

                        // to just remove the toast...but this can cause clients

                        // who miss the timeout due to normal circumstances (e.g.

                        // running under debugger) to crash (b/29105388). The windows will

                        // eventually be removed when the client process finishes.

                        // The best we can do for now is remove the FLAG_KEEP_SCREEN_ON

                        // and prevent the symptoms of b/21693547.

                        window.mAttrs.flags &= ~FLAG_KEEP_SCREEN_ON;

                        window.setDisplayLayoutNeeded();

                        mWindowPlacerLocked.performSurfacePlacement();

                    }

                }

                break;