From 249283ffa0d82bfdc1c1445e5c336fbdb659de90 Mon Sep 17 00:00:00 2001
From: Jing Ji <jji@google.com>
Date: Sat, 19 Nov 2022 22:10:39 -0800
Subject: [PATCH] Add a developer option to disable app child process
 restrictions

Bug: 205156966
Test: atest PhantomProcessPreferenceControllerTest
Change-Id: I87fd78b3dc7dea069823de6bef0bd7fe20d985ad
---
 res/values/strings.xml                        |   5 +
 res/xml/development_settings.xml              |   6 +
 .../DevelopmentSettingsDashboardFragment.java |   1 +
 .../PhantomProcessPreferenceController.java   |  87 ++++++++++++++
 ...hantomProcessPreferenceControllerTest.java | 107 ++++++++++++++++++
 5 files changed, 206 insertions(+)
 create mode 100644 src/com/android/settings/development/PhantomProcessPreferenceController.java
 create mode 100644 tests/unit/src/com/android/settings/development/PhantomProcessPreferenceControllerTest.java

diff --git a/res/values/strings.xml b/res/values/strings.xml
index 0fd961702ad..233cb6a85d0 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -11267,6 +11267,11 @@
     <!-- Developer Settings: Dialog ListPreference option to disable network bandwidth ingress rate limit [CHAR LIMIT=none] -->
     <string name="ingress_rate_limit_no_limit_entry">No limit</string>
 
+    <!-- Developer settings: Title for disabling phantom process monitoring. [CHAR LIMIT=50]-->
+    <string name="disable_phantom_process_monitor_title">Disable child process restrictions</string>
+    <!-- Developer settings: Summary for disabling phantom process monitoring. [CHAR LIMIT=NONE]-->
+    <string name="disable_phantom_process_monitor_summary">Disable restrictions on the system resource usage of the app child processes</string>
+
     <!-- BT LE Audio Device: Media Broadcast -->
     <!-- The title of the Media Broadcast Dialog [CHAR LIMIT=none] -->
     <string name="bluetooth_broadcast_dialog_title">Broadcast</string>
diff --git a/res/xml/development_settings.xml b/res/xml/development_settings.xml
index a0640f5be70..9e864b83bbb 100644
--- a/res/xml/development_settings.xml
+++ b/res/xml/development_settings.xml
@@ -672,6 +672,12 @@
         <Preference
             android:key="reset_shortcut_manager_throttling"
             android:title="@string/reset_shortcut_manager_throttling" />
+
+        <SwitchPreference
+            android:key="disable_phantom_process_monitor"
+            android:title="@string/disable_phantom_process_monitor_title"
+            android:summary="@string/disable_phantom_process_monitor_summary" />
+
     </PreferenceCategory>
 
     <PreferenceCategory
diff --git a/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java b/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java
index 4cd34750a88..8ff23365a5a 100644
--- a/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java
+++ b/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java
@@ -656,6 +656,7 @@ public class DevelopmentSettingsDashboardFragment extends RestrictedDashboardFra
         controllers.add(new StylusHandwritingPreferenceController(context));
         controllers.add(new IngressRateLimitPreferenceController((context)));
         controllers.add(new BackAnimationPreferenceController(context, fragment));
+        controllers.add(new PhantomProcessPreferenceController(context));
 
         return controllers;
     }
diff --git a/src/com/android/settings/development/PhantomProcessPreferenceController.java b/src/com/android/settings/development/PhantomProcessPreferenceController.java
new file mode 100644
index 00000000000..b277fe1fdb7
--- /dev/null
+++ b/src/com/android/settings/development/PhantomProcessPreferenceController.java
@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2022 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 com.android.settings.development;
+
+import static android.util.FeatureFlagUtils.SETTINGS_ENABLE_MONITOR_PHANTOM_PROCS;
+
+import android.content.Context;
+import android.util.FeatureFlagUtils;
+import android.util.Log;
+
+import androidx.preference.Preference;
+import androidx.preference.SwitchPreference;
+
+import com.android.settings.core.PreferenceControllerMixin;
+import com.android.settingslib.development.DeveloperOptionsPreferenceController;
+
+/**
+ * PreferenceController for MockModem
+ */
+public class PhantomProcessPreferenceController extends
+        DeveloperOptionsPreferenceController implements Preference.OnPreferenceChangeListener,
+        PreferenceControllerMixin {
+
+    private static final String TAG = "PhantomProcessPreferenceController";
+    private static final String DISABLE_PHANTOM_PROCESS_MONITOR_KEY =
+            "disable_phantom_process_monitor";
+
+    public PhantomProcessPreferenceController(Context context) {
+        super(context);
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return DISABLE_PHANTOM_PROCESS_MONITOR_KEY;
+    }
+
+    @Override
+    public boolean onPreferenceChange(Preference preference, Object newValue) {
+        final boolean isEnabled = (Boolean) newValue; // true means we're disabling this flag.
+        try {
+            FeatureFlagUtils.setEnabled(mContext,
+                    SETTINGS_ENABLE_MONITOR_PHANTOM_PROCS,
+                    !isEnabled);
+        } catch (RuntimeException e) {
+            Log.e(TAG, "Fail to set feature flag: " + e.getMessage());
+        }
+        return true;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        try {
+            final boolean isEnabled = !FeatureFlagUtils.isEnabled(mContext,
+                    SETTINGS_ENABLE_MONITOR_PHANTOM_PROCS);
+            ((SwitchPreference) mPreference).setChecked(isEnabled);
+        } catch (RuntimeException e) {
+            Log.e(TAG, "Fail to get feature flag: " + e.getMessage());
+        }
+    }
+
+    @Override
+    protected void onDeveloperOptionsSwitchDisabled() {
+        super.onDeveloperOptionsSwitchDisabled();
+        try {
+            FeatureFlagUtils.setEnabled(mContext,
+                    SETTINGS_ENABLE_MONITOR_PHANTOM_PROCS,
+                    true /* Enable the monitoring */);
+            ((SwitchPreference) mPreference).setChecked(false);
+        } catch (RuntimeException e) {
+            Log.e(TAG, "Fail to set feature flag: " + e.getMessage());
+        }
+    }
+}
diff --git a/tests/unit/src/com/android/settings/development/PhantomProcessPreferenceControllerTest.java b/tests/unit/src/com/android/settings/development/PhantomProcessPreferenceControllerTest.java
new file mode 100644
index 00000000000..7ebde1bbb8c
--- /dev/null
+++ b/tests/unit/src/com/android/settings/development/PhantomProcessPreferenceControllerTest.java
@@ -0,0 +1,107 @@
+/*
+ * Copyright (C) 2022 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 com.android.settings.development;
+
+import static android.util.FeatureFlagUtils.SETTINGS_ENABLE_MONITOR_PHANTOM_PROCS;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.content.Context;
+import android.os.Looper;
+import android.util.FeatureFlagUtils;
+
+import androidx.preference.PreferenceManager;
+import androidx.preference.PreferenceScreen;
+import androidx.preference.SwitchPreference;
+import androidx.test.core.app.ApplicationProvider;
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@RunWith(AndroidJUnit4.class)
+public class PhantomProcessPreferenceControllerTest {
+
+    private Context mContext;
+    private PhantomProcessPreferenceController mController;
+    private SwitchPreference mPreference;
+
+    @Before
+    public void setUp() {
+        mContext = ApplicationProvider.getApplicationContext();
+        mController = new PhantomProcessPreferenceController(mContext);
+        if (Looper.myLooper() == null) {
+            Looper.prepare();
+        }
+
+        final PreferenceManager preferenceManager = new PreferenceManager(mContext);
+        final PreferenceScreen screen = preferenceManager.createPreferenceScreen(mContext);
+        mPreference = new SwitchPreference(mContext);
+        mPreference.setKey(mController.getPreferenceKey());
+        screen.addPreference(mPreference);
+        mController.displayPreference(screen);
+    }
+
+    @Test
+    public void onPreferenceChanged_settingDisabled_shouldNotDisablePhantomProcessMonitor() {
+        mController.onPreferenceChange(mPreference, false /* new value */);
+
+        final boolean mode = !FeatureFlagUtils.isEnabled(mContext,
+                SETTINGS_ENABLE_MONITOR_PHANTOM_PROCS);
+
+        assertThat(mode).isFalse();
+    }
+
+    @Test
+    public void onPreferenceChanged_settingEnabled_shouldDisablePhantomProcessMonitor() {
+        mController.onPreferenceChange(mPreference, true /* new value */);
+
+        final boolean mode = !FeatureFlagUtils.isEnabled(mContext,
+                SETTINGS_ENABLE_MONITOR_PHANTOM_PROCS);
+
+        assertThat(mode).isTrue();
+    }
+
+    @Test
+    public void updateState_settingEnabled_preferenceShouldBeChecked() {
+        FeatureFlagUtils.setEnabled(mContext, SETTINGS_ENABLE_MONITOR_PHANTOM_PROCS, false);
+
+        mController.updateState(mPreference);
+        assertThat(mPreference.isChecked()).isTrue();
+    }
+
+    @Test
+    public void updateState_settingDisabled_preferenceShouldNotBeChecked() {
+        FeatureFlagUtils.setEnabled(mContext, SETTINGS_ENABLE_MONITOR_PHANTOM_PROCS, true);
+
+        mController.updateState(mPreference);
+        assertThat(mPreference.isChecked()).isFalse();
+    }
+
+    @Test
+    public void onDeveloperOptionsDisabled_shouldDisablePreference() {
+        mController.onDeveloperOptionsSwitchDisabled();
+        final boolean mode = !FeatureFlagUtils.isEnabled(mContext,
+                SETTINGS_ENABLE_MONITOR_PHANTOM_PROCS);
+
+        mController.updateState(mPreference);
+
+        assertThat(mode).isFalse();
+        assertThat(mPreference.isChecked()).isFalse();
+    }
+}