From df259d3021d892ff404afb857176465bc82cd8bb Mon Sep 17 00:00:00 2001
From: Robert Carr <racarr@google.com>
Date: Mon, 5 Dec 2016 20:33:10 -0800
Subject: [PATCH] Correct error in Configuration.updateFrom

When updating the non direction members of screenLayout
we check that they are not in total undefined, before
accepting the new value in full. This was enough for LONG/SIZE
which are always undefined or set together. It seems we have paths
now where SCREENLAYOUT_ROUND however can be undefined and the others
will be set. In this case if we pass a configuration with
SCREENLAYOUT_ROUND_UNDEFINED but LONG/SIZE set to updateFrom then
we will overwrite our previous SCREENLAYOUT_ROUND value.
This triggers extra configuration changes. We take extra care with
SCREENLAYOUT_COMPAT_NEEDED as it doesn't have an undefined value.

Bug: 33098677
Test: bit FrameworksCoreTests:android.content.res.ConfigurationTest
Change-Id: I6e7d123d5444f93c511aeb6e0f3adfea2a480352
---
 .../android/content/res/Configuration.java    | 38 ++++++++----
 .../content/res/ConfigurationTest.java        | 58 +++++++++++++++++++
 2 files changed, 86 insertions(+), 10 deletions(-)
 create mode 100644 core/tests/coretests/src/android/content/res/ConfigurationTest.java

diff --git a/core/java/android/content/res/Configuration.java b/core/java/android/content/res/Configuration.java
index ee1f1907fcb87..227dc91cf108a 100644
--- a/core/java/android/content/res/Configuration.java
+++ b/core/java/android/content/res/Configuration.java
@@ -1047,18 +1047,36 @@ public final class Configuration implements Parcelable, Comparable<Configuration
             changed |= ActivityInfo.CONFIG_ORIENTATION;
             orientation = delta.orientation;
         }
-        if (getScreenLayoutNoDirection(delta.screenLayout) !=
-                    (SCREENLAYOUT_SIZE_UNDEFINED | SCREENLAYOUT_LONG_UNDEFINED)
-                && (getScreenLayoutNoDirection(screenLayout) !=
-                    getScreenLayoutNoDirection(delta.screenLayout))) {
+
+        if (((delta.screenLayout & SCREENLAYOUT_SIZE_MASK) != SCREENLAYOUT_SIZE_UNDEFINED)
+                && (delta.screenLayout & SCREENLAYOUT_SIZE_MASK)
+                != (screenLayout & SCREENLAYOUT_SIZE_MASK)) {
             changed |= ActivityInfo.CONFIG_SCREEN_LAYOUT;
-            // We need to preserve the previous layout dir bits if they were defined
-            if ((delta.screenLayout&SCREENLAYOUT_LAYOUTDIR_MASK) == 0) {
-                screenLayout = (screenLayout&SCREENLAYOUT_LAYOUTDIR_MASK)|delta.screenLayout;
-            } else {
-                screenLayout = delta.screenLayout;
-            }
+            screenLayout = (screenLayout & ~SCREENLAYOUT_SIZE_MASK)
+                    | (delta.screenLayout & SCREENLAYOUT_SIZE_MASK);
         }
+        if (((delta.screenLayout & SCREENLAYOUT_LONG_MASK) != SCREENLAYOUT_LONG_UNDEFINED)
+                && (delta.screenLayout & SCREENLAYOUT_LONG_MASK)
+                != (screenLayout & SCREENLAYOUT_LONG_MASK)) {
+            changed |= ActivityInfo.CONFIG_SCREEN_LAYOUT;
+            screenLayout = (screenLayout & ~SCREENLAYOUT_LONG_MASK)
+                    | (delta.screenLayout & SCREENLAYOUT_LONG_MASK);
+        }
+        if (((delta.screenLayout & SCREENLAYOUT_ROUND_MASK) != SCREENLAYOUT_ROUND_UNDEFINED)
+                && (delta.screenLayout & SCREENLAYOUT_ROUND_MASK)
+                != (screenLayout & SCREENLAYOUT_ROUND_MASK)) {
+            changed |= ActivityInfo.CONFIG_SCREEN_LAYOUT;
+            screenLayout = (screenLayout & ~SCREENLAYOUT_ROUND_MASK)
+                    | (delta.screenLayout & SCREENLAYOUT_ROUND_MASK);
+        }
+        if ((delta.screenLayout & SCREENLAYOUT_COMPAT_NEEDED)
+                != (screenLayout & SCREENLAYOUT_COMPAT_NEEDED)
+                && delta.screenLayout != 0) {
+            changed |= ActivityInfo.CONFIG_SCREEN_LAYOUT;
+            screenLayout = (screenLayout & ~SCREENLAYOUT_COMPAT_NEEDED)
+                | (delta.screenLayout & SCREENLAYOUT_COMPAT_NEEDED);
+        }
+
         if (delta.uiMode != (UI_MODE_TYPE_UNDEFINED|UI_MODE_NIGHT_UNDEFINED)
                 && uiMode != delta.uiMode) {
             changed |= ActivityInfo.CONFIG_UI_MODE;
diff --git a/core/tests/coretests/src/android/content/res/ConfigurationTest.java b/core/tests/coretests/src/android/content/res/ConfigurationTest.java
new file mode 100644
index 0000000000000..72b9197089d7b
--- /dev/null
+++ b/core/tests/coretests/src/android/content/res/ConfigurationTest.java
@@ -0,0 +1,58 @@
+/*
+1;3409;0c * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package android.content.res;
+
+import org.junit.runner.RunWith;
+import org.junit.Test;
+import org.junit.runners.JUnit4;
+
+import android.content.res.Configuration;
+import android.support.test.filters.SmallTest;
+import android.platform.test.annotations.Presubmit;
+
+import junit.framework.TestCase;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * Build/install/run: bit FrameworksCoreTests:android.content.res.ConfigurationTest
+ */
+@RunWith(JUnit4.class)
+@SmallTest
+@Presubmit
+public class ConfigurationTest extends TestCase {
+    @Test
+    public void testUpdateFromPreservesRoundBit() {
+        Configuration config = new Configuration();
+        config.screenLayout = Configuration.SCREENLAYOUT_ROUND_YES;
+        Configuration config2 = new Configuration();
+
+        config.updateFrom(config2);
+        assertEquals(config.screenLayout, Configuration.SCREENLAYOUT_ROUND_YES);
+    }
+
+    @Test
+    public void testUpdateFromPreservesCompatNeededBit() {
+        Configuration config = new Configuration();
+        config.screenLayout = Configuration.SCREENLAYOUT_COMPAT_NEEDED;
+        Configuration config2 = new Configuration();
+        config.updateFrom(config2);
+        assertEquals(config.screenLayout, Configuration.SCREENLAYOUT_COMPAT_NEEDED);
+
+        config2.updateFrom(config);
+        assertEquals(config2.screenLayout, Configuration.SCREENLAYOUT_COMPAT_NEEDED);
+    }
+}