From 58d89b491668663963e66906196fd93b9c73ee80 Mon Sep 17 00:00:00 2001
From: Valentin Iftime <valiiftime@google.com>
Date: Mon, 16 Oct 2023 09:29:17 +0200
Subject: [PATCH] Prioritize system toasts

 Insert toasts from system packages at the front of the queue
  to ensure that apps can't spam with toast to delay system toasts from showing.
 Also increase Clipboard paste warning toasts length to LENGTH_LONG.

Test: atest NotificationManagerServiceTest
Bug: 293301736

Change-Id: I13547f853476bc88d12026c545aba9f857ce8724
Merged-In: I13547f853476bc88d12026c545aba9f857ce8724
---
 .../server/clipboard/ClipboardService.java    |  2 +-
 .../NotificationManagerService.java           | 32 ++++++++-
 .../NotificationManagerServiceTest.java       | 68 +++++++++++++++++++
 3 files changed, 99 insertions(+), 3 deletions(-)

diff --git a/services/core/java/com/android/server/clipboard/ClipboardService.java b/services/core/java/com/android/server/clipboard/ClipboardService.java
index 61350bb6095e..b6fec61f2a11 100644
--- a/services/core/java/com/android/server/clipboard/ClipboardService.java
+++ b/services/core/java/com/android/server/clipboard/ClipboardService.java
@@ -1109,7 +1109,7 @@ public class ClipboardService extends SystemService {
                         getContext().getString(R.string.pasted_from_clipboard, callingAppLabel);
                 Slog.i(TAG, message);
                 Toast.makeText(
-                        getContext(), UiThread.get().getLooper(), message, Toast.LENGTH_SHORT)
+                        getContext(), UiThread.get().getLooper(), message, Toast.LENGTH_LONG)
                         .show();
             } catch (PackageManager.NameNotFoundException e) {
                 // do nothing
diff --git a/services/core/java/com/android/server/notification/NotificationManagerService.java b/services/core/java/com/android/server/notification/NotificationManagerService.java
index 4ddc72ed610b..6a02c6eb61eb 100755
--- a/services/core/java/com/android/server/notification/NotificationManagerService.java
+++ b/services/core/java/com/android/server/notification/NotificationManagerService.java
@@ -3315,8 +3315,19 @@ public class NotificationManagerService extends SystemService {
                                 null /* options */);
                         record = getToastRecord(callingUid, callingPid, pkg, isSystemToast, token,
                                 text, callback, duration, windowToken, displayId, textCallback);
-                        mToastQueue.add(record);
-                        index = mToastQueue.size() - 1;
+
+                        // Insert system toasts at the front of the queue
+                        int systemToastInsertIdx = mToastQueue.size();
+                        if (isSystemToast) {
+                            systemToastInsertIdx = getInsertIndexForSystemToastLocked();
+                        }
+                        if (systemToastInsertIdx < mToastQueue.size()) {
+                            index = systemToastInsertIdx;
+                            mToastQueue.add(index, record);
+                        } else {
+                            mToastQueue.add(record);
+                            index = mToastQueue.size() - 1;
+                        }
                         keepProcessAliveForToastIfNeededLocked(callingPid);
                     }
                     // If it's at index 0, it's the current toast.  It doesn't matter if it's
@@ -3332,6 +3343,23 @@ public class NotificationManagerService extends SystemService {
             }
         }
 
+        @GuardedBy("mToastQueue")
+        private int getInsertIndexForSystemToastLocked() {
+            // If there are other system toasts: insert after the last one
+            int idx = 0;
+            for (ToastRecord r : mToastQueue) {
+                if (idx == 0 && mIsCurrentToastShown) {
+                    idx++;
+                    continue;
+                }
+                if (!r.isSystemToast) {
+                    return idx;
+                }
+                idx++;
+            }
+            return idx;
+        }
+
         private boolean checkCanEnqueueToast(String pkg, int callingUid,
                 boolean isAppRenderedToast, boolean isSystemToast) {
             final boolean isPackageSuspended = isPackagePaused(pkg);
diff --git a/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java b/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
index 8c60178f44fe..0912aa3f635b 100755
--- a/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
+++ b/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
@@ -6839,6 +6839,74 @@ public class NotificationManagerServiceTest extends UiServiceTestCase {
         assertEquals(NotificationManagerService.MAX_PACKAGE_TOASTS, mService.mToastQueue.size());
     }
 
+    @Test
+    public void testPrioritizeSystemToasts() throws Exception {
+        // Insert non-system toasts
+        final String testPackage = "testPackageName";
+        assertEquals(0, mService.mToastQueue.size());
+        mService.isSystemUid = false;
+        mService.isSystemAppId = false;
+        setToastRateIsWithinQuota(true);
+        setIfPackageHasPermissionToAvoidToastRateLimiting(testPackage, false);
+
+        // package is not suspended
+        when(mPackageManager.isPackageSuspendedForUser(testPackage, UserHandle.getUserId(mUid)))
+                .thenReturn(false);
+
+        INotificationManager nmService = (INotificationManager) mService.mService;
+
+        // Enqueue maximum number of toasts for test package
+        for (int i = 0; i < NotificationManagerService.MAX_PACKAGE_TOASTS; i++) {
+            nmService.enqueueTextToast(testPackage, new Binder(), "Text", 2000, 0, null);
+        }
+
+        // Enqueue system toast
+        final String testPackageSystem = "testPackageNameSystem";
+        mService.isSystemUid = true;
+        setIfPackageHasPermissionToAvoidToastRateLimiting(testPackageSystem, false);
+        when(mPackageManager.isPackageSuspendedForUser(testPackageSystem, UserHandle.getUserId(mUid)))
+                .thenReturn(false);
+
+        nmService.enqueueToast(testPackageSystem, new Binder(), new TestableToastCallback(), 2000, 0);
+
+        // System toast is inserted at the front of the queue, behind current showing toast
+        assertEquals(testPackageSystem, mService.mToastQueue.get(1).pkg);
+    }
+
+    @Test
+    public void testPrioritizeSystemToasts_enqueueAfterExistingSystemToast() throws Exception {
+        // Insert system toasts
+        final String testPackageSystem1 = "testPackageNameSystem1";
+        assertEquals(0, mService.mToastQueue.size());
+        mService.isSystemUid = true;
+        setToastRateIsWithinQuota(true);
+        setIfPackageHasPermissionToAvoidToastRateLimiting(testPackageSystem1, false);
+
+        // package is not suspended
+        when(mPackageManager.isPackageSuspendedForUser(testPackageSystem1, UserHandle.getUserId(mUid)))
+                .thenReturn(false);
+
+        INotificationManager nmService = (INotificationManager) mService.mService;
+
+        // Enqueue maximum number of toasts for test package
+        for (int i = 0; i < NotificationManagerService.MAX_PACKAGE_TOASTS; i++) {
+            nmService.enqueueTextToast(testPackageSystem1, new Binder(), "Text", 2000, 0, null);
+        }
+
+        // Enqueue another system toast
+        final String testPackageSystem2 = "testPackageNameSystem2";
+        mService.isSystemUid = true;
+        setIfPackageHasPermissionToAvoidToastRateLimiting(testPackageSystem2, false);
+        when(mPackageManager.isPackageSuspendedForUser(testPackageSystem2, UserHandle.getUserId(mUid)))
+                .thenReturn(false);
+
+        nmService.enqueueToast(testPackageSystem2, new Binder(), new TestableToastCallback(), 2000, 0);
+
+        // System toast is inserted at the back of the queue, after the other system toasts
+        assertEquals(testPackageSystem2,
+                mService.mToastQueue.get(mService.mToastQueue.size() - 1).pkg);
+    }
+
     private void setAppInForegroundForToasts(int uid, boolean inForeground) {
         int importance = (inForeground) ? IMPORTANCE_FOREGROUND : IMPORTANCE_NONE;
         when(mActivityManager.getUidImportance(mUid)).thenReturn(importance);
-- 
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