Reset fingers and buttons in GestureConverter::reset

Previously, calling reset didn't really reset anything, which could have
resulted in an inconsistent event stream (e.g. fake fingers that were
put down but never raised).

Bug: 251196347
Bug: 259547750
Test: atest inputflinger_tests
Test: scroll, swipe, and pinch on a touchpad, check dispatched events
Change-Id: If95cde96f1974bf7c98009c68e2637686bff96cc
diff --git a/services/inputflinger/reader/mapper/TouchpadInputMapper.cpp b/services/inputflinger/reader/mapper/TouchpadInputMapper.cpp
index 4c56b05..5e63e48 100644
--- a/services/inputflinger/reader/mapper/TouchpadInputMapper.cpp
+++ b/services/inputflinger/reader/mapper/TouchpadInputMapper.cpp
@@ -256,8 +256,9 @@
 
 std::list<NotifyArgs> TouchpadInputMapper::reset(nsecs_t when) {
     mStateConverter.reset();
-    mGestureConverter.reset();
-    return InputMapper::reset(when);
+    std::list<NotifyArgs> out = mGestureConverter.reset(when);
+    out += InputMapper::reset(when);
+    return out;
 }
 
 std::list<NotifyArgs> TouchpadInputMapper::process(const RawEvent* rawEvent) {
diff --git a/services/inputflinger/reader/mapper/gestures/GestureConverter.cpp b/services/inputflinger/reader/mapper/gestures/GestureConverter.cpp
index 707b1f3..fd2be5f 100644
--- a/services/inputflinger/reader/mapper/gestures/GestureConverter.cpp
+++ b/services/inputflinger/reader/mapper/gestures/GestureConverter.cpp
@@ -72,8 +72,32 @@
     return out.str();
 }
 
-void GestureConverter::reset() {
-    mButtonState = 0;
+std::list<NotifyArgs> GestureConverter::reset(nsecs_t when) {
+    std::list<NotifyArgs> out;
+    switch (mCurrentClassification) {
+        case MotionClassification::TWO_FINGER_SWIPE:
+            out.push_back(endScroll(when, when));
+            break;
+        case MotionClassification::MULTI_FINGER_SWIPE:
+            out += handleMultiFingerSwipeLift(when, when);
+            break;
+        case MotionClassification::PINCH:
+            out += endPinch(when, when);
+            break;
+        case MotionClassification::NONE:
+            // When a button is pressed, the Gestures library always ends the current gesture,
+            // so we don't have to worry about the case where buttons need to be lifted during a
+            // pinch or swipe.
+            if (mButtonState) {
+                out += releaseAllButtons(when, when);
+            }
+            break;
+        default:
+            break;
+    }
+    mCurrentClassification = MotionClassification::NONE;
+    mDownTime = 0;
+    return out;
 }
 
 void GestureConverter::populateMotionRanges(InputDeviceInfo& info) const {
@@ -219,6 +243,39 @@
     return out;
 }
 
+std::list<NotifyArgs> GestureConverter::releaseAllButtons(nsecs_t when, nsecs_t readTime) {
+    std::list<NotifyArgs> out;
+    const auto [xCursorPosition, yCursorPosition] = mPointerController->getPosition();
+
+    PointerCoords coords;
+    coords.clear();
+    coords.setAxisValue(AMOTION_EVENT_AXIS_X, xCursorPosition);
+    coords.setAxisValue(AMOTION_EVENT_AXIS_Y, yCursorPosition);
+    coords.setAxisValue(AMOTION_EVENT_AXIS_RELATIVE_X, 0);
+    coords.setAxisValue(AMOTION_EVENT_AXIS_RELATIVE_Y, 0);
+    const bool pointerDown = isPointerDown(mButtonState);
+    coords.setAxisValue(AMOTION_EVENT_AXIS_PRESSURE, pointerDown ? 1.0f : 0.0f);
+    uint32_t newButtonState = mButtonState;
+    for (uint32_t button = AMOTION_EVENT_BUTTON_PRIMARY; button <= AMOTION_EVENT_BUTTON_FORWARD;
+         button <<= 1) {
+        if (mButtonState & button) {
+            newButtonState &= ~button;
+            out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_BUTTON_RELEASE,
+                                         button, newButtonState, /*pointerCount=*/1,
+                                         mFingerProps.data(), &coords, xCursorPosition,
+                                         yCursorPosition));
+        }
+    }
+    if (pointerDown) {
+        coords.setAxisValue(AMOTION_EVENT_AXIS_PRESSURE, 0.0f);
+        out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_UP, /*actionButton=*/0,
+                                     newButtonState, /*pointerCount=*/1, mFingerProps.data(),
+                                     &coords, xCursorPosition, yCursorPosition));
+    }
+    mButtonState = 0;
+    return out;
+}
+
 std::list<NotifyArgs> GestureConverter::handleScroll(nsecs_t when, nsecs_t readTime,
                                                      const Gesture& gesture) {
     std::list<NotifyArgs> out;
@@ -264,6 +321,10 @@
         return {};
     }
 
+    return endScroll(when, readTime);
+}
+
+NotifyArgs GestureConverter::endScroll(nsecs_t when, nsecs_t readTime) {
     const auto [xCursorPosition, yCursorPosition] = mPointerController->getPosition();
     mFakeFingerCoords[0].setAxisValue(AMOTION_EVENT_AXIS_GESTURE_SCROLL_X_DISTANCE, 0);
     mFakeFingerCoords[0].setAxisValue(AMOTION_EVENT_AXIS_GESTURE_SCROLL_Y_DISTANCE, 0);
@@ -366,8 +427,6 @@
 
 [[nodiscard]] std::list<NotifyArgs> GestureConverter::handlePinch(nsecs_t when, nsecs_t readTime,
                                                                   const Gesture& gesture) {
-    std::list<NotifyArgs> out;
-
     const auto [xCursorPosition, yCursorPosition] = mPointerController->getPosition();
 
     // Pinch gesture phases are reported a little differently from others, in that the same details
@@ -391,6 +450,7 @@
         mFakeFingerCoords[1].setAxisValue(AMOTION_EVENT_AXIS_Y, yCursorPosition);
         mFakeFingerCoords[1].setAxisValue(AMOTION_EVENT_AXIS_PRESSURE, 1.0f);
         mDownTime = when;
+        std::list<NotifyArgs> out;
         out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_DOWN,
                                      /* actionButton= */ 0, mButtonState, /* pointerCount= */ 1,
                                      mFingerProps.data(), mFakeFingerCoords.data(), xCursorPosition,
@@ -405,19 +465,7 @@
     }
 
     if (gesture.details.pinch.zoom_state == GESTURES_ZOOM_END) {
-        mFakeFingerCoords[0].setAxisValue(AMOTION_EVENT_AXIS_GESTURE_PINCH_SCALE_FACTOR, 1.0);
-        out.push_back(makeMotionArgs(when, readTime,
-                                     AMOTION_EVENT_ACTION_POINTER_UP |
-                                             1 << AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT,
-                                     /* actionButton= */ 0, mButtonState, /* pointerCount= */ 2,
-                                     mFingerProps.data(), mFakeFingerCoords.data(), xCursorPosition,
-                                     yCursorPosition));
-        out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_UP, /* actionButton= */ 0,
-                                     mButtonState, /* pointerCount= */ 1, mFingerProps.data(),
-                                     mFakeFingerCoords.data(), xCursorPosition, yCursorPosition));
-        mCurrentClassification = MotionClassification::NONE;
-        mFakeFingerCoords[0].setAxisValue(AMOTION_EVENT_AXIS_GESTURE_PINCH_SCALE_FACTOR, 0);
-        return out;
+        return endPinch(when, readTime);
     }
 
     mPinchFingerSeparation *= gesture.details.pinch.dz;
@@ -429,9 +477,27 @@
     mFakeFingerCoords[1].setAxisValue(AMOTION_EVENT_AXIS_X,
                                       xCursorPosition + mPinchFingerSeparation / 2);
     mFakeFingerCoords[1].setAxisValue(AMOTION_EVENT_AXIS_Y, yCursorPosition);
-    out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_MOVE, /* actionButton= */ 0,
-                                 mButtonState, /* pointerCount= */ 2, mFingerProps.data(),
+    return {makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_MOVE, /*actionButton=*/0,
+                           mButtonState, /*pointerCount=*/2, mFingerProps.data(),
+                           mFakeFingerCoords.data(), xCursorPosition, yCursorPosition)};
+}
+
+std::list<NotifyArgs> GestureConverter::endPinch(nsecs_t when, nsecs_t readTime) {
+    std::list<NotifyArgs> out;
+    const auto [xCursorPosition, yCursorPosition] = mPointerController->getPosition();
+
+    mFakeFingerCoords[0].setAxisValue(AMOTION_EVENT_AXIS_GESTURE_PINCH_SCALE_FACTOR, 1.0);
+    out.push_back(makeMotionArgs(when, readTime,
+                                 AMOTION_EVENT_ACTION_POINTER_UP |
+                                         1 << AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT,
+                                 /*actionButton=*/0, mButtonState, /*pointerCount=*/2,
+                                 mFingerProps.data(), mFakeFingerCoords.data(), xCursorPosition,
+                                 yCursorPosition));
+    out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_UP, /*actionButton=*/0,
+                                 mButtonState, /*pointerCount=*/1, mFingerProps.data(),
                                  mFakeFingerCoords.data(), xCursorPosition, yCursorPosition));
+    mCurrentClassification = MotionClassification::NONE;
+    mFakeFingerCoords[0].setAxisValue(AMOTION_EVENT_AXIS_GESTURE_PINCH_SCALE_FACTOR, 0);
     return out;
 }
 
diff --git a/services/inputflinger/reader/mapper/gestures/GestureConverter.h b/services/inputflinger/reader/mapper/gestures/GestureConverter.h
index a10dcce..2714d03 100644
--- a/services/inputflinger/reader/mapper/gestures/GestureConverter.h
+++ b/services/inputflinger/reader/mapper/gestures/GestureConverter.h
@@ -44,7 +44,7 @@
     std::string dump() const;
 
     void setOrientation(ui::Rotation orientation) { mOrientation = orientation; }
-    void reset();
+    [[nodiscard]] std::list<NotifyArgs> reset(nsecs_t when);
 
     void populateMotionRanges(InputDeviceInfo& info) const;
 
@@ -55,15 +55,19 @@
     [[nodiscard]] NotifyArgs handleMove(nsecs_t when, nsecs_t readTime, const Gesture& gesture);
     [[nodiscard]] std::list<NotifyArgs> handleButtonsChange(nsecs_t when, nsecs_t readTime,
                                                             const Gesture& gesture);
+    [[nodiscard]] std::list<NotifyArgs> releaseAllButtons(nsecs_t when, nsecs_t readTime);
     [[nodiscard]] std::list<NotifyArgs> handleScroll(nsecs_t when, nsecs_t readTime,
                                                      const Gesture& gesture);
     [[nodiscard]] NotifyArgs handleFling(nsecs_t when, nsecs_t readTime, const Gesture& gesture);
+    [[nodiscard]] NotifyArgs endScroll(nsecs_t when, nsecs_t readTime);
+
     [[nodiscard]] std::list<NotifyArgs> handleMultiFingerSwipe(nsecs_t when, nsecs_t readTime,
                                                                uint32_t fingerCount, float dx,
                                                                float dy);
     [[nodiscard]] std::list<NotifyArgs> handleMultiFingerSwipeLift(nsecs_t when, nsecs_t readTime);
     [[nodiscard]] std::list<NotifyArgs> handlePinch(nsecs_t when, nsecs_t readTime,
                                                     const Gesture& gesture);
+    [[nodiscard]] std::list<NotifyArgs> endPinch(nsecs_t when, nsecs_t readTime);
 
     NotifyMotionArgs makeMotionArgs(nsecs_t when, nsecs_t readTime, int32_t action,
                                     int32_t actionButton, int32_t buttonState,
diff --git a/services/inputflinger/tests/GestureConverter_test.cpp b/services/inputflinger/tests/GestureConverter_test.cpp
index bbf7e8e..33f404d 100644
--- a/services/inputflinger/tests/GestureConverter_test.cpp
+++ b/services/inputflinger/tests/GestureConverter_test.cpp
@@ -785,4 +785,107 @@
                       WithGesturePinchScaleFactor(0, EPSILON)));
 }
 
+TEST_F(GestureConverterTest, ResetWithButtonPressed) {
+    InputDeviceContext deviceContext(*mDevice, EVENTHUB_ID);
+    GestureConverter converter(*mReader->getContext(), deviceContext, DEVICE_ID);
+
+    Gesture downGesture(kGestureButtonsChange, ARBITRARY_GESTURE_TIME, ARBITRARY_GESTURE_TIME,
+                        /*down=*/GESTURES_BUTTON_LEFT | GESTURES_BUTTON_RIGHT,
+                        /*up=*/GESTURES_BUTTON_NONE, /*is_tap=*/false);
+    (void)converter.handleGesture(ARBITRARY_TIME, READ_TIME, downGesture);
+
+    std::list<NotifyArgs> args = converter.reset(ARBITRARY_TIME);
+    ASSERT_EQ(3u, args.size());
+
+    EXPECT_THAT(std::get<NotifyMotionArgs>(args.front()),
+                AllOf(WithMotionAction(AMOTION_EVENT_ACTION_BUTTON_RELEASE),
+                      WithActionButton(AMOTION_EVENT_BUTTON_PRIMARY),
+                      WithButtonState(AMOTION_EVENT_BUTTON_SECONDARY),
+                      WithCoords(POINTER_X, POINTER_Y),
+                      WithToolType(AMOTION_EVENT_TOOL_TYPE_FINGER)));
+    args.pop_front();
+    EXPECT_THAT(std::get<NotifyMotionArgs>(args.front()),
+                AllOf(WithMotionAction(AMOTION_EVENT_ACTION_BUTTON_RELEASE),
+                      WithActionButton(AMOTION_EVENT_BUTTON_SECONDARY), WithButtonState(0),
+                      WithCoords(POINTER_X, POINTER_Y),
+                      WithToolType(AMOTION_EVENT_TOOL_TYPE_FINGER)));
+    args.pop_front();
+    ASSERT_THAT(std::get<NotifyMotionArgs>(args.front()),
+                AllOf(WithMotionAction(AMOTION_EVENT_ACTION_UP), WithButtonState(0),
+                      WithCoords(POINTER_X, POINTER_Y),
+                      WithToolType(AMOTION_EVENT_TOOL_TYPE_FINGER)));
+}
+
+TEST_F(GestureConverterTest, ResetDuringScroll) {
+    InputDeviceContext deviceContext(*mDevice, EVENTHUB_ID);
+    GestureConverter converter(*mReader->getContext(), deviceContext, DEVICE_ID);
+
+    Gesture startGesture(kGestureScroll, ARBITRARY_GESTURE_TIME, ARBITRARY_GESTURE_TIME, 0, -10);
+    (void)converter.handleGesture(ARBITRARY_TIME, READ_TIME, startGesture);
+
+    std::list<NotifyArgs> args = converter.reset(ARBITRARY_TIME);
+    ASSERT_EQ(1u, args.size());
+    ASSERT_THAT(std::get<NotifyMotionArgs>(args.front()),
+                AllOf(WithMotionAction(AMOTION_EVENT_ACTION_UP),
+                      WithCoords(POINTER_X, POINTER_Y - 10),
+                      WithGestureScrollDistance(0, 0, EPSILON),
+                      WithMotionClassification(MotionClassification::TWO_FINGER_SWIPE),
+                      WithToolType(AMOTION_EVENT_TOOL_TYPE_FINGER),
+                      WithFlags(AMOTION_EVENT_FLAG_IS_GENERATED_GESTURE)));
+}
+
+TEST_F(GestureConverterTest, ResetDuringThreeFingerSwipe) {
+    InputDeviceContext deviceContext(*mDevice, EVENTHUB_ID);
+    GestureConverter converter(*mReader->getContext(), deviceContext, DEVICE_ID);
+
+    Gesture startGesture(kGestureSwipe, ARBITRARY_GESTURE_TIME, ARBITRARY_GESTURE_TIME, /*dx=*/0,
+                         /*dy=*/10);
+    (void)converter.handleGesture(ARBITRARY_TIME, READ_TIME, startGesture);
+
+    std::list<NotifyArgs> args = converter.reset(ARBITRARY_TIME);
+    ASSERT_EQ(3u, args.size());
+    EXPECT_THAT(std::get<NotifyMotionArgs>(args.front()),
+                AllOf(WithMotionAction(AMOTION_EVENT_ACTION_POINTER_UP |
+                                       2 << AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT),
+                      WithGestureOffset(0, 0, EPSILON),
+                      WithMotionClassification(MotionClassification::MULTI_FINGER_SWIPE),
+                      WithPointerCount(3u), WithToolType(AMOTION_EVENT_TOOL_TYPE_FINGER)));
+    args.pop_front();
+    EXPECT_THAT(std::get<NotifyMotionArgs>(args.front()),
+                AllOf(WithMotionAction(AMOTION_EVENT_ACTION_POINTER_UP |
+                                       1 << AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT),
+                      WithGestureOffset(0, 0, EPSILON),
+                      WithMotionClassification(MotionClassification::MULTI_FINGER_SWIPE),
+                      WithPointerCount(2u), WithToolType(AMOTION_EVENT_TOOL_TYPE_FINGER)));
+    args.pop_front();
+    EXPECT_THAT(std::get<NotifyMotionArgs>(args.front()),
+                AllOf(WithMotionAction(AMOTION_EVENT_ACTION_UP), WithGestureOffset(0, 0, EPSILON),
+                      WithMotionClassification(MotionClassification::MULTI_FINGER_SWIPE),
+                      WithPointerCount(1u), WithToolType(AMOTION_EVENT_TOOL_TYPE_FINGER)));
+}
+
+TEST_F(GestureConverterTest, ResetDuringPinch) {
+    InputDeviceContext deviceContext(*mDevice, EVENTHUB_ID);
+    GestureConverter converter(*mReader->getContext(), deviceContext, DEVICE_ID);
+
+    Gesture startGesture(kGesturePinch, ARBITRARY_GESTURE_TIME, ARBITRARY_GESTURE_TIME, /*dz=*/1,
+                         GESTURES_ZOOM_START);
+    (void)converter.handleGesture(ARBITRARY_TIME, READ_TIME, startGesture);
+
+    std::list<NotifyArgs> args = converter.reset(ARBITRARY_TIME);
+    ASSERT_EQ(2u, args.size());
+    EXPECT_THAT(std::get<NotifyMotionArgs>(args.front()),
+                AllOf(WithMotionAction(AMOTION_EVENT_ACTION_POINTER_UP |
+                                       1 << AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT),
+                      WithMotionClassification(MotionClassification::PINCH),
+                      WithGesturePinchScaleFactor(1.0f, EPSILON), WithPointerCount(2u),
+                      WithToolType(AMOTION_EVENT_TOOL_TYPE_FINGER)));
+    args.pop_front();
+    EXPECT_THAT(std::get<NotifyMotionArgs>(args.front()),
+                AllOf(WithMotionAction(AMOTION_EVENT_ACTION_UP),
+                      WithMotionClassification(MotionClassification::PINCH),
+                      WithGesturePinchScaleFactor(1.0f, EPSILON), WithPointerCount(1u),
+                      WithToolType(AMOTION_EVENT_TOOL_TYPE_FINGER)));
+}
+
 } // namespace android