GestureConverter: add option to make 3-finger tap a shortcut

By default, it will remain as middle-click, but if the user chooses to
customize it we'll handle it like a special keyboard shortcut by sending
a JNI call up to InputManagerService.

Test: 3-finger tap with flag enabled, check log line appears
Test: 3-finger tap with flag disabled, check button events appear at
    https://w3c.github.io/uievents/tools/mouse-event-viewer.html
Test: atest inputflinger_test:GestureConverterTest
Test: m checkinput
Flag: com.android.hardware.input.touchpad_three_finger_tap_shortcut
Bug: 365063048
Change-Id: I771d46e1aafe9164dd32771cfdb55a3b259b5a0d

Author: HarryCutts

services/inputflinger/include/InputReaderBase.h

@@ -242,6 +242,9 @@ struct InputReaderConfiguration {
     // context (a.k.a. "right") clicks.
     bool touchpadRightClickZoneEnabled;
 
+    // True to use three-finger tap as a customizable shortcut; false to use it as a middle-click.
+    bool touchpadThreeFingerTapShortcutEnabled;
+
     // The set of currently disabled input devices.
     std::set<int32_t> disabledDevices;
 
@@ -293,6 +296,7 @@ struct InputReaderConfiguration {
             touchpadTapDraggingEnabled(false),
             shouldNotifyTouchpadHardwareState(false),
             touchpadRightClickZoneEnabled(false),
+            touchpadThreeFingerTapShortcutEnabled(false),
             stylusButtonMotionEventsEnabled(true),
             stylusPointerIconEnabled(false),
             mouseReverseVerticalScrollingEnabled(false),
@@ -496,6 +500,9 @@ class InputReaderPolicyInterface : public virtual RefBase {
     /* Sends the Info of gestures that happen on the touchpad. */
     virtual void notifyTouchpadGestureInfo(GestureType type, int32_t deviceId) = 0;
 
+    /* Notifies the policy that the user has performed a three-finger touchpad tap. */
+    virtual void notifyTouchpadThreeFingerTap() = 0;
+
     /* Gets the keyboard layout for a particular input device. */
     virtual std::shared_ptr<KeyCharacterMap> getKeyboardLayoutOverlay(
             const InputDeviceIdentifier& identifier,

services/inputflinger/reader/mapper/TouchpadInputMapper.cpp

@@ -375,6 +375,9 @@ std::list<NotifyArgs> TouchpadInputMapper::reconfigure(nsecs_t when,
         mPropertyProvider.getProperty("Button Right Click Zone Enable")
                 .setBoolValues({config.touchpadRightClickZoneEnabled});
         mTouchpadHardwareStateNotificationsEnabled = config.shouldNotifyTouchpadHardwareState;
+
+        mGestureConverter.setThreeFingerTapShortcutEnabled(
+                config.touchpadThreeFingerTapShortcutEnabled);
     }
     std::list<NotifyArgs> out;
     if ((!changes.any() && config.pointerCaptureRequest.isEnable()) ||

services/inputflinger/reader/mapper/gestures/GestureConverter.cpp

@@ -261,6 +261,14 @@ std::list<NotifyArgs> GestureConverter::handleButtonsChange(nsecs_t when, nsecs_
     }
 
     const uint32_t buttonsPressed = gesture.details.buttons.down;
+    const uint32_t buttonsReleased = gesture.details.buttons.up;
+
+    if (mThreeFingerTapShortcutEnabled && gesture.details.buttons.is_tap &&
+        buttonsPressed == GESTURES_BUTTON_MIDDLE && buttonsReleased == GESTURES_BUTTON_MIDDLE) {
+        mReaderContext.getPolicy()->notifyTouchpadThreeFingerTap();
+        return out;
+    }
+
     bool pointerDown = isPointerDown(mButtonState) ||
             buttonsPressed &
                     (GESTURES_BUTTON_LEFT | GESTURES_BUTTON_MIDDLE | GESTURES_BUTTON_RIGHT);
@@ -291,7 +299,6 @@ std::list<NotifyArgs> GestureConverter::handleButtonsChange(nsecs_t when, nsecs_
     // changes: a set of buttons going down, followed by a set of buttons going up.
     mButtonState = newButtonState;
 
-    const uint32_t buttonsReleased = gesture.details.buttons.up;
     for (uint32_t button = 1; button <= GESTURES_BUTTON_FORWARD; button <<= 1) {
         if (buttonsReleased & button) {
             uint32_t actionButton = gesturesButtonToMotionEventButton(button);

services/inputflinger/reader/mapper/gestures/GestureConverter.h

@@ -55,6 +55,10 @@ class GestureConverter {
 
     void setBoundsInLogicalDisplay(FloatRect bounds) { mBoundsInLogicalDisplay = bounds; }
 
+    void setThreeFingerTapShortcutEnabled(bool enabled) {
+        mThreeFingerTapShortcutEnabled = enabled;
+    }
+
     void populateMotionRanges(InputDeviceInfo& info) const;
 
     [[nodiscard]] std::list<NotifyArgs> handleGesture(nsecs_t when, nsecs_t readTime,
@@ -101,6 +105,8 @@ class GestureConverter {
     const bool mEnableFlingStop;
     const bool mEnableNoFocusChange;
 
+    bool mThreeFingerTapShortcutEnabled;
+
     std::optional<ui::LogicalDisplayId> mDisplayId;
     FloatRect mBoundsInLogicalDisplay{};
     ui::Rotation mOrientation = ui::ROTATION_0;

services/inputflinger/tests/FakeInputReaderPolicy.cpp

@@ -80,6 +80,17 @@ void FakeInputReaderPolicy::assertTouchpadHardwareStateNotified() {
     ASSERT_TRUE(success) << "Timed out waiting for hardware state to be notified";
 }
 
+void FakeInputReaderPolicy::assertTouchpadThreeFingerTapNotified() {
+    std::unique_lock lock(mLock);
+    base::ScopedLockAssertion assumeLocked(mLock);
+
+    const bool success =
+            mTouchpadThreeFingerTapNotified.wait_for(lock, WAIT_TIMEOUT, [this]() REQUIRES(mLock) {
+                return mTouchpadThreeFingerTapHasBeenReported;
+            });
+    ASSERT_TRUE(success) << "Timed out waiting for three-finger tap to be notified";
+}
+
 void FakeInputReaderPolicy::clearViewports() {
     mViewports.clear();
     mConfig.setDisplayViewports(mViewports);
@@ -259,6 +270,12 @@ void FakeInputReaderPolicy::notifyTouchpadGestureInfo(GestureType type, int32_t
     std::scoped_lock lock(mLock);
 }
 
+void FakeInputReaderPolicy::notifyTouchpadThreeFingerTap() {
+    std::scoped_lock lock(mLock);
+    mTouchpadThreeFingerTapHasBeenReported = true;
+    mTouchpadThreeFingerTapNotified.notify_all();
+}
+
 std::shared_ptr<KeyCharacterMap> FakeInputReaderPolicy::getKeyboardLayoutOverlay(
         const InputDeviceIdentifier&, const std::optional<KeyboardLayoutInfo>) {
     return nullptr;

services/inputflinger/tests/FakeInputReaderPolicy.h

@@ -43,6 +43,7 @@ class FakeInputReaderPolicy : public InputReaderPolicyInterface {
     void assertStylusGestureNotified(int32_t deviceId);
     void assertStylusGestureNotNotified();
     void assertTouchpadHardwareStateNotified();
+    void assertTouchpadThreeFingerTapNotified();
 
     virtual void clearViewports();
     std::optional<DisplayViewport> getDisplayViewportByUniqueId(const std::string& uniqueId) const;
@@ -86,6 +87,7 @@ class FakeInputReaderPolicy : public InputReaderPolicyInterface {
     void notifyTouchpadHardwareState(const SelfContainedHardwareState& schs,
                                      int32_t deviceId) override;
     void notifyTouchpadGestureInfo(GestureType type, int32_t deviceId) override;
+    void notifyTouchpadThreeFingerTap() override;
     std::shared_ptr<KeyCharacterMap> getKeyboardLayoutOverlay(
             const InputDeviceIdentifier&, const std::optional<KeyboardLayoutInfo>) override;
     std::string getDeviceAlias(const InputDeviceIdentifier&) override;
@@ -109,6 +111,9 @@ class FakeInputReaderPolicy : public InputReaderPolicyInterface {
     std::condition_variable mTouchpadHardwareStateNotified;
     std::optional<SelfContainedHardwareState> mTouchpadHardwareState GUARDED_BY(mLock){};
 
+    std::condition_variable mTouchpadThreeFingerTapNotified;
+    bool mTouchpadThreeFingerTapHasBeenReported{false};
+
     uint32_t mNextPointerCaptureSequenceNumber{0};
 };
 

services/inputflinger/tests/GestureConverter_test.cpp

@@ -1272,6 +1272,27 @@ TEST_F(GestureConverterTest, Tap) {
                               WithDisplayId(ui::LogicalDisplayId::DEFAULT)))));
 }
 
+TEST_F(GestureConverterTest, ThreeFingerTap_TriggersShortcut) {
+    InputDeviceContext deviceContext(*mDevice, EVENTHUB_ID);
+    GestureConverter converter(*mReader->getContext(), deviceContext, DEVICE_ID);
+    converter.setDisplayId(ui::LogicalDisplayId::DEFAULT);
+    converter.setThreeFingerTapShortcutEnabled(true);
+
+    Gesture flingGesture(kGestureFling, ARBITRARY_GESTURE_TIME, ARBITRARY_GESTURE_TIME, /*vx=*/0,
+                         /*vy=*/0, GESTURES_FLING_TAP_DOWN);
+    std::list<NotifyArgs> args =
+            converter.handleGesture(ARBITRARY_TIME, READ_TIME, ARBITRARY_TIME, flingGesture);
+    // We don't need to check args here, since it's covered by the FlingTapDown test.
+
+    Gesture tapGesture(kGestureButtonsChange, ARBITRARY_GESTURE_TIME, ARBITRARY_GESTURE_TIME,
+                       /*down=*/GESTURES_BUTTON_MIDDLE, /*up=*/GESTURES_BUTTON_MIDDLE,
+                       /*is_tap=*/true);
+    args = converter.handleGesture(ARBITRARY_TIME, READ_TIME, ARBITRARY_TIME, tapGesture);
+
+    ASSERT_TRUE(args.empty());
+    mFakePolicy->assertTouchpadThreeFingerTapNotified();
+}
+
 TEST_F(GestureConverterTest, Click) {
     // Click should produce button press/release events
     InputDeviceContext deviceContext(*mDevice, EVENTHUB_ID);

services/inputflinger/tests/fuzzers/MapperHelpers.h

@@ -288,6 +288,7 @@ class FuzzInputReaderPolicy : public InputReaderPolicyInterface {
     void notifyTouchpadHardwareState(const SelfContainedHardwareState& schs,
                                      int32_t deviceId) override {}
     void notifyTouchpadGestureInfo(GestureType type, int32_t deviceId) override {}
+    void notifyTouchpadThreeFingerTap() override {}
     std::shared_ptr<KeyCharacterMap> getKeyboardLayoutOverlay(
             const InputDeviceIdentifier& identifier,
             const std::optional<KeyboardLayoutInfo> layoutInfo) override {