Disable deep press when long press timeout is long

If the user sets the long press timeout to anything > default value,
then we should disable deep press. That means, if the user is triggering
long press too easily, it is likely that the user will trigger deep
press too easily as well.
To prevent unwanted long press invocations, we disable deep press in
such situations.

Bug: 148311342
Test: Add logging to both cases where deep press is enabled and
disabled. Go to accessibility -> touch & hold delay, and change the
value. Ensure that the logging matches expectation (short -> enable,
medium/long -> disable). The state should persist across the reboot.

Change-Id: Ic631c684609c4436e9eaa6f9389939c5a6e4e1cd
Merged-In: Ic631c684609c4436e9eaa6f9389939c5a6e4e1cd
(cherry picked from commit c9ac19eb3d3c3f185fea95906541249dd4c3baf8)
diff --git a/services/inputflinger/Android.bp b/services/inputflinger/Android.bp
index 4ec4e25..f67c9d0 100644
--- a/services/inputflinger/Android.bp
+++ b/services/inputflinger/Android.bp
@@ -52,7 +52,6 @@
         "libstatslog",
         "libutils",
         "libui",
-        "server_configurable_flags",
     ],
 }
 
diff --git a/services/inputflinger/InputClassifier.cpp b/services/inputflinger/InputClassifier.cpp
index 8ba1f7f..77a0716 100644
--- a/services/inputflinger/InputClassifier.cpp
+++ b/services/inputflinger/InputClassifier.cpp
@@ -27,7 +27,6 @@
 #if defined(__linux__)
     #include <pthread.h>
 #endif
-#include <server_configurable_flags/get_flags.h>
 #include <unordered_set>
 
 #include <android/hardware/input/classifier/1.0/IInputClassifier.h>
@@ -46,11 +45,6 @@
 
 namespace android {
 
-// Category (=namespace) name for the input settings that are applied at boot time
-static const char* INPUT_NATIVE_BOOT = "input_native_boot";
-// Feature flag name for the deep press feature
-static const char* DEEP_PRESS_ENABLED = "deep_press_enabled";
-
 //Max number of elements to store in mEvents.
 static constexpr size_t MAX_EVENTS = 5;
 
@@ -77,20 +71,6 @@
     return args.source == AINPUT_SOURCE_TOUCHPAD || args.source == AINPUT_SOURCE_TOUCHSCREEN;
 }
 
-// Check if the "deep touch" feature is on.
-static bool deepPressEnabled() {
-    std::string flag_value = server_configurable_flags::GetServerConfigurableFlag(
-            INPUT_NATIVE_BOOT, DEEP_PRESS_ENABLED, "true");
-    std::transform(flag_value.begin(), flag_value.end(), flag_value.begin(), ::tolower);
-    if (flag_value == "1" || flag_value == "true") {
-        ALOGI("Deep press feature enabled.");
-        return true;
-    }
-    ALOGI("Deep press feature is not enabled.");
-    return false;
-}
-
-
 // --- ClassifierEvent ---
 
 ClassifierEvent::ClassifierEvent(std::unique_ptr<NotifyMotionArgs> args) :
@@ -157,12 +137,6 @@
 
 std::unique_ptr<MotionClassifierInterface> MotionClassifier::create(
         sp<android::hardware::hidl_death_recipient> deathRecipient) {
-    if (!deepPressEnabled()) {
-        // If feature is not enabled, MotionClassifier should stay null to avoid unnecessary work.
-        // When MotionClassifier is null, InputClassifier will forward all events
-        // to the next InputListener, unmodified.
-        return nullptr;
-    }
     sp<android::hardware::input::classifier::V1_0::IInputClassifier> service =
             classifier::V1_0::IInputClassifier::getService();
     if (!service) {
@@ -372,14 +346,25 @@
 // --- InputClassifier ---
 
 InputClassifier::InputClassifier(const sp<InputListenerInterface>& listener)
-      : mListener(listener), mHalDeathRecipient(new HalDeathRecipient(*this)) {
-    mInitializeMotionClassifierThread = std::thread(
-            [this] { setMotionClassifier(MotionClassifier::create(mHalDeathRecipient)); });
+      : mListener(listener), mHalDeathRecipient(new HalDeathRecipient(*this)) {}
+
+void InputClassifier::setMotionClassifierEnabled(bool enabled) {
+    if (enabled) {
+        ALOGI("Enabling motion classifier");
+        if (mInitializeMotionClassifierThread.joinable()) {
+            mInitializeMotionClassifierThread.join();
+        }
+        mInitializeMotionClassifierThread = std::thread(
+                [this] { setMotionClassifier(MotionClassifier::create(mHalDeathRecipient)); });
 #if defined(__linux__)
-    // Set the thread name for debugging
-    pthread_setname_np(mInitializeMotionClassifierThread.native_handle(),
-                       "Create MotionClassifier");
+        // Set the thread name for debugging
+        pthread_setname_np(mInitializeMotionClassifierThread.native_handle(),
+                           "Create MotionClassifier");
 #endif
+    } else {
+        ALOGI("Disabling motion classifier");
+        setMotionClassifier(nullptr);
+    }
 }
 
 void InputClassifier::notifyConfigurationChanged(const NotifyConfigurationChangedArgs* args) {
@@ -429,8 +414,6 @@
 void InputClassifier::dump(std::string& dump) {
     std::scoped_lock lock(mLock);
     dump += "Input Classifier State:\n";
-    dump += StringPrintf(INDENT1 "Deep press: %s\n", deepPressEnabled() ? "enabled" : "disabled");
-
     dump += INDENT1 "Motion Classifier:\n";
     if (mMotionClassifier) {
         mMotionClassifier->dump(dump);
@@ -441,7 +424,9 @@
 }
 
 InputClassifier::~InputClassifier() {
-    mInitializeMotionClassifierThread.join();
+    if (mInitializeMotionClassifierThread.joinable()) {
+        mInitializeMotionClassifierThread.join();
+    }
 }
 
 } // namespace android
diff --git a/services/inputflinger/InputClassifier.h b/services/inputflinger/InputClassifier.h
index 8f58695..03510a6 100644
--- a/services/inputflinger/InputClassifier.h
+++ b/services/inputflinger/InputClassifier.h
@@ -90,6 +90,7 @@
  */
 class InputClassifierInterface : public virtual RefBase, public InputListenerInterface {
 public:
+    virtual void setMotionClassifierEnabled(bool enabled) = 0;
     /**
      * Dump the state of the input classifier.
      * This method may be called on any thread (usually by the input manager).
@@ -234,6 +235,9 @@
 
     ~InputClassifier();
 
+    // Called from InputManager
+    virtual void setMotionClassifierEnabled(bool enabled) override;
+
 private:
     // Protect access to mMotionClassifier, since it may become null via a hidl callback
     std::mutex mLock;
diff --git a/services/inputflinger/InputManager.cpp b/services/inputflinger/InputManager.cpp
index c7c61cf..fc771a2 100644
--- a/services/inputflinger/InputManager.cpp
+++ b/services/inputflinger/InputManager.cpp
@@ -132,4 +132,8 @@
     mDispatcher->unregisterInputChannel(channel);
 }
 
+void InputManager::setMotionClassifierEnabled(bool enabled) {
+    mClassifier->setMotionClassifierEnabled(enabled);
+}
+
 } // namespace android
diff --git a/services/inputflinger/InputManager.h b/services/inputflinger/InputManager.h
index 586097f..0158441 100644
--- a/services/inputflinger/InputManager.h
+++ b/services/inputflinger/InputManager.h
@@ -100,6 +100,8 @@
     virtual void registerInputChannel(const sp<InputChannel>& channel);
     virtual void unregisterInputChannel(const sp<InputChannel>& channel);
 
+    void setMotionClassifierEnabled(bool enabled);
+
 private:
     sp<InputReaderInterface> mReader;
 
diff --git a/services/inputflinger/tests/InputClassifier_test.cpp b/services/inputflinger/tests/InputClassifier_test.cpp
index b4e755a..ab74a04 100644
--- a/services/inputflinger/tests/InputClassifier_test.cpp
+++ b/services/inputflinger/tests/InputClassifier_test.cpp
@@ -135,6 +135,28 @@
     ASSERT_EQ(args, outArgs);
 }
 
+TEST_F(InputClassifierTest, SetMotionClassifier_Enabled) {
+    mClassifier->setMotionClassifierEnabled(true);
+}
+
+TEST_F(InputClassifierTest, SetMotionClassifier_Disabled) {
+    mClassifier->setMotionClassifierEnabled(false);
+}
+
+/**
+ * Try to break it by calling setMotionClassifierEnabled multiple times.
+ */
+TEST_F(InputClassifierTest, SetMotionClassifier_Multiple) {
+    mClassifier->setMotionClassifierEnabled(true);
+    mClassifier->setMotionClassifierEnabled(true);
+    mClassifier->setMotionClassifierEnabled(true);
+    mClassifier->setMotionClassifierEnabled(false);
+    mClassifier->setMotionClassifierEnabled(false);
+    mClassifier->setMotionClassifierEnabled(true);
+    mClassifier->setMotionClassifierEnabled(true);
+    mClassifier->setMotionClassifierEnabled(true);
+}
+
 /**
  * A minimal implementation of IInputClassifier.
  */