services/inputflinger/reader/mapper/TouchpadInputMapper.cpp - android_frameworks_native - Gitiles

 /*
  * Copyright 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.
  */

 #include "../Macros.h"

 #include <android/input.h>
 #include <log/log_main.h>
 #include "TouchCursorInputMapperCommon.h"
 #include "TouchpadInputMapper.h"

 namespace android {

 namespace {

 short getMaxTouchCount(const InputDeviceContext& context) {
     if (context.hasScanCode(BTN_TOOL_QUINTTAP)) return 5;
     if (context.hasScanCode(BTN_TOOL_QUADTAP)) return 4;
     if (context.hasScanCode(BTN_TOOL_TRIPLETAP)) return 3;
     if (context.hasScanCode(BTN_TOOL_DOUBLETAP)) return 2;
     if (context.hasScanCode(BTN_TOOL_FINGER)) return 1;
     return 0;
 }

 HardwareProperties createHardwareProperties(const InputDeviceContext& context) {
     HardwareProperties props;
     RawAbsoluteAxisInfo absMtPositionX;
     context.getAbsoluteAxisInfo(ABS_MT_POSITION_X, &absMtPositionX);
     props.left = absMtPositionX.minValue;
     props.right = absMtPositionX.maxValue;
     props.res_x = absMtPositionX.resolution;

     RawAbsoluteAxisInfo absMtPositionY;
     context.getAbsoluteAxisInfo(ABS_MT_POSITION_Y, &absMtPositionY);
     props.top = absMtPositionY.minValue;
     props.bottom = absMtPositionY.maxValue;
     props.res_y = absMtPositionY.resolution;

     RawAbsoluteAxisInfo absMtOrientation;
     context.getAbsoluteAxisInfo(ABS_MT_ORIENTATION, &absMtOrientation);
     props.orientation_minimum = absMtOrientation.minValue;
     props.orientation_maximum = absMtOrientation.maxValue;

     RawAbsoluteAxisInfo absMtSlot;
     context.getAbsoluteAxisInfo(ABS_MT_SLOT, &absMtSlot);
     props.max_finger_cnt = absMtSlot.maxValue - absMtSlot.minValue + 1;
     props.max_touch_cnt = getMaxTouchCount(context);

     // T5R2 ("Track 5, Report 2") is a feature of some old Synaptics touchpads that could track 5
     // fingers but only report the coordinates of 2 of them. We don't know of any external touchpads
     // that did this, so assume false.
     props.supports_t5r2 = false;

     props.support_semi_mt = context.hasInputProperty(INPUT_PROP_SEMI_MT);
     props.is_button_pad = context.hasInputProperty(INPUT_PROP_BUTTONPAD);

     // Mouse-only properties, which will always be false.
     props.has_wheel = false;
     props.wheel_is_hi_res = false;

     // Linux Kernel haptic touchpad support isn't merged yet, so for now assume that no touchpads
     // are haptic.
     props.is_haptic_pad = false;
     return props;
 }

 void gestureInterpreterCallback(void* clientData, const Gesture* gesture) {
     TouchpadInputMapper* mapper = static_cast<TouchpadInputMapper*>(clientData);
     mapper->consumeGesture(gesture);
 }

 uint32_t gesturesButtonToMotionEventButton(uint32_t gesturesButton) {
     switch (gesturesButton) {
         case GESTURES_BUTTON_LEFT:
             return AMOTION_EVENT_BUTTON_PRIMARY;
         case GESTURES_BUTTON_MIDDLE:
             return AMOTION_EVENT_BUTTON_TERTIARY;
         case GESTURES_BUTTON_RIGHT:
             return AMOTION_EVENT_BUTTON_SECONDARY;
         case GESTURES_BUTTON_BACK:
             return AMOTION_EVENT_BUTTON_BACK;
         case GESTURES_BUTTON_FORWARD:
             return AMOTION_EVENT_BUTTON_FORWARD;
         default:
             return 0;
     }
 }

 } // namespace

 TouchpadInputMapper::TouchpadInputMapper(InputDeviceContext& deviceContext)
       : InputMapper(deviceContext),
         mGestureInterpreter(NewGestureInterpreter(), DeleteGestureInterpreter),
         mPointerController(getContext()->getPointerController(getDeviceId())),
         mStateConverter(deviceContext) {
     mGestureInterpreter->Initialize(GESTURES_DEVCLASS_TOUCHPAD);
     mGestureInterpreter->SetHardwareProperties(createHardwareProperties(deviceContext));
     // Even though we don't explicitly delete copy/move semantics, it's safe to
     // give away a pointer to TouchpadInputMapper here because
     // 1) mGestureInterpreter's lifecycle is determined by TouchpadInputMapper, and
     // 2) TouchpadInputMapper is stored as a unique_ptr and not moved.
     mGestureInterpreter->SetCallback(gestureInterpreterCallback, this);
     // TODO(b/251196347): set a property provider, so we can change gesture properties.
     // TODO(b/251196347): set a timer provider, so the library can use timers.
 }

 TouchpadInputMapper::~TouchpadInputMapper() {
     if (mPointerController != nullptr) {
         mPointerController->fade(PointerControllerInterface::Transition::IMMEDIATE);
     }
 }

 uint32_t TouchpadInputMapper::getSources() const {
     return AINPUT_SOURCE_MOUSE | AINPUT_SOURCE_TOUCHPAD;
 }

 std::list<NotifyArgs> TouchpadInputMapper::reset(nsecs_t when) {
     mStateConverter.reset();

     mButtonState = 0;
     return InputMapper::reset(when);
 }

 std::list<NotifyArgs> TouchpadInputMapper::process(const RawEvent* rawEvent) {
     std::optional<SelfContainedHardwareState> state = mStateConverter.processRawEvent(rawEvent);
     if (state) {
         return sendHardwareState(rawEvent->when, rawEvent->readTime, *state);
     } else {
         return {};
     }
 }

 std::list<NotifyArgs> TouchpadInputMapper::sendHardwareState(nsecs_t when, nsecs_t readTime,
                                                              SelfContainedHardwareState schs) {
     mProcessing = true;
     mGestureInterpreter->PushHardwareState(&schs.state);
     mProcessing = false;

     return processGestures(when, readTime);
 }

 void TouchpadInputMapper::consumeGesture(const Gesture* gesture) {
     ALOGD("Gesture ready: %s", gesture->String().c_str());
     if (!mProcessing) {
         ALOGE("Received gesture outside of the normal processing flow; ignoring it.");
         return;
     }
     mGesturesToProcess.push_back(*gesture);
 }

 std::list<NotifyArgs> TouchpadInputMapper::processGestures(nsecs_t when, nsecs_t readTime) {
     std::list<NotifyArgs> out = {};
     for (Gesture& gesture : mGesturesToProcess) {
         switch (gesture.type) {
             case kGestureTypeMove:
                 out.push_back(handleMove(when, readTime, gesture));
                 break;
             case kGestureTypeButtonsChange:
                 out += handleButtonsChange(when, readTime, gesture);
                 break;
             default:
                 // TODO(b/251196347): handle more gesture types.
                 break;
         }
     }
     mGesturesToProcess.clear();
     return out;
 }

 NotifyArgs TouchpadInputMapper::handleMove(nsecs_t when, nsecs_t readTime, const Gesture& gesture) {
     PointerProperties props;
     props.clear();
     props.id = 0;
     props.toolType = AMOTION_EVENT_TOOL_TYPE_FINGER;

     mPointerController->setPresentation(PointerControllerInterface::Presentation::POINTER);
     mPointerController->move(gesture.details.move.dx, gesture.details.move.dy);
     mPointerController->unfade(PointerControllerInterface::Transition::IMMEDIATE);
     float xCursorPosition, yCursorPosition;
     mPointerController->getPosition(&xCursorPosition, &yCursorPosition);

     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, gesture.details.move.dx);
     coords.setAxisValue(AMOTION_EVENT_AXIS_RELATIVE_Y, gesture.details.move.dy);
     const bool down = isPointerDown(mButtonState);
     coords.setAxisValue(AMOTION_EVENT_AXIS_PRESSURE, down ? 1.0f : 0.0f);

     const int32_t action = down ? AMOTION_EVENT_ACTION_MOVE : AMOTION_EVENT_ACTION_HOVER_MOVE;
     return makeMotionArgs(when, readTime, action, /* actionButton= */ 0, mButtonState,
                           /* pointerCount= */ 1, &props, &coords, xCursorPosition, yCursorPosition);
 }

 std::list<NotifyArgs> TouchpadInputMapper::handleButtonsChange(nsecs_t when, nsecs_t readTime,
                                                                const Gesture& gesture) {
     std::list<NotifyArgs> out = {};

     mPointerController->setPresentation(PointerControllerInterface::Presentation::POINTER);
     mPointerController->unfade(PointerControllerInterface::Transition::IMMEDIATE);

     PointerProperties props;
     props.clear();
     props.id = 0;
     props.toolType = AMOTION_EVENT_TOOL_TYPE_FINGER;

     float xCursorPosition, yCursorPosition;
     mPointerController->getPosition(&xCursorPosition, &yCursorPosition);

     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 uint32_t buttonsPressed = gesture.details.buttons.down;
     bool pointerDown = isPointerDown(mButtonState) ||
             buttonsPressed &
                     (GESTURES_BUTTON_LEFT | GESTURES_BUTTON_MIDDLE | GESTURES_BUTTON_RIGHT);
     coords.setAxisValue(AMOTION_EVENT_AXIS_PRESSURE, pointerDown ? 1.0f : 0.0f);

     uint32_t newButtonState = mButtonState;
     std::list<NotifyArgs> pressEvents = {};
     for (uint32_t button = 1; button <= GESTURES_BUTTON_FORWARD; button <<= 1) {
         if (buttonsPressed & button) {
             uint32_t actionButton = gesturesButtonToMotionEventButton(button);
             newButtonState |= actionButton;
             pressEvents.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_BUTTON_PRESS,
                                                  actionButton, newButtonState,
                                                  /* pointerCount= */ 1, &props, &coords,
                                                  xCursorPosition, yCursorPosition));
         }
     }
     if (!isPointerDown(mButtonState) && isPointerDown(newButtonState)) {
         mDownTime = when;
         out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_DOWN,
                                      /* actionButton= */ 0, newButtonState, /* pointerCount= */ 1,
                                      &props, &coords, xCursorPosition, yCursorPosition));
     }
     out.splice(out.end(), pressEvents);

     // The same button may be in both down and up in the same gesture, in which case we should treat
     // it as having gone down and then up. So, we treat a single button change gesture as two state
     // 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);
             newButtonState &= ~actionButton;
             out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_BUTTON_RELEASE,
                                          actionButton, newButtonState, /* pointerCount= */ 1,
                                          &props, &coords, xCursorPosition, yCursorPosition));
         }
     }
     if (isPointerDown(mButtonState) && !isPointerDown(newButtonState)) {
         coords.setAxisValue(AMOTION_EVENT_AXIS_PRESSURE, 0.0f);
         out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_UP, /* actionButton= */ 0,
                                      newButtonState, /* pointerCount= */ 1, &props, &coords,
                                      xCursorPosition, yCursorPosition));
     }
     mButtonState = newButtonState;
     return out;
 }

 NotifyMotionArgs TouchpadInputMapper::makeMotionArgs(nsecs_t when, nsecs_t readTime, int32_t action,
                                                      int32_t actionButton, int32_t buttonState,
                                                      uint32_t pointerCount,
                                                      const PointerProperties* pointerProperties,
                                                      const PointerCoords* pointerCoords,
                                                      float xCursorPosition, float yCursorPosition) {
     // TODO(b/260226362): consider what the appropriate source for these events is.
     const uint32_t source = AINPUT_SOURCE_MOUSE;

     return NotifyMotionArgs(getContext()->getNextId(), when, readTime, getDeviceId(), source,
                             mPointerController->getDisplayId(), /* policyFlags= */ 0, action,
                             /* actionButton= */ actionButton, /* flags= */ 0,
                             getContext()->getGlobalMetaState(), buttonState,
                             MotionClassification::NONE, AMOTION_EVENT_EDGE_FLAG_NONE, pointerCount,
                             pointerProperties, pointerCoords,
                             /* xPrecision= */ 1.0f, /* yPrecision= */ 1.0f, xCursorPosition,
                             yCursorPosition, /* downTime= */ mDownTime, /* videoFrames= */ {});
 }

 } // namespace android
	/*
	* Copyright 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.
	*/

	#include "../Macros.h"

	#include <android/input.h>
	#include <log/log_main.h>
	#include "TouchCursorInputMapperCommon.h"
	#include "TouchpadInputMapper.h"

	namespace android {

	namespace {

	short getMaxTouchCount(const InputDeviceContext& context) {
	if (context.hasScanCode(BTN_TOOL_QUINTTAP)) return 5;
	if (context.hasScanCode(BTN_TOOL_QUADTAP)) return 4;
	if (context.hasScanCode(BTN_TOOL_TRIPLETAP)) return 3;
	if (context.hasScanCode(BTN_TOOL_DOUBLETAP)) return 2;
	if (context.hasScanCode(BTN_TOOL_FINGER)) return 1;
	return 0;
	}

	HardwareProperties createHardwareProperties(const InputDeviceContext& context) {
	HardwareProperties props;
	RawAbsoluteAxisInfo absMtPositionX;
	context.getAbsoluteAxisInfo(ABS_MT_POSITION_X, &absMtPositionX);
	props.left = absMtPositionX.minValue;
	props.right = absMtPositionX.maxValue;
	props.res_x = absMtPositionX.resolution;

	RawAbsoluteAxisInfo absMtPositionY;
	context.getAbsoluteAxisInfo(ABS_MT_POSITION_Y, &absMtPositionY);
	props.top = absMtPositionY.minValue;
	props.bottom = absMtPositionY.maxValue;
	props.res_y = absMtPositionY.resolution;

	RawAbsoluteAxisInfo absMtOrientation;
	context.getAbsoluteAxisInfo(ABS_MT_ORIENTATION, &absMtOrientation);
	props.orientation_minimum = absMtOrientation.minValue;
	props.orientation_maximum = absMtOrientation.maxValue;

	RawAbsoluteAxisInfo absMtSlot;
	context.getAbsoluteAxisInfo(ABS_MT_SLOT, &absMtSlot);
	props.max_finger_cnt = absMtSlot.maxValue - absMtSlot.minValue + 1;
	props.max_touch_cnt = getMaxTouchCount(context);

	// T5R2 ("Track 5, Report 2") is a feature of some old Synaptics touchpads that could track 5
	// fingers but only report the coordinates of 2 of them. We don't know of any external touchpads
	// that did this, so assume false.
	props.supports_t5r2 = false;

	props.support_semi_mt = context.hasInputProperty(INPUT_PROP_SEMI_MT);
	props.is_button_pad = context.hasInputProperty(INPUT_PROP_BUTTONPAD);

	// Mouse-only properties, which will always be false.
	props.has_wheel = false;
	props.wheel_is_hi_res = false;

	// Linux Kernel haptic touchpad support isn't merged yet, so for now assume that no touchpads
	// are haptic.
	props.is_haptic_pad = false;
	return props;
	}

	void gestureInterpreterCallback(void* clientData, const Gesture* gesture) {
	TouchpadInputMapper* mapper = static_cast<TouchpadInputMapper*>(clientData);
	mapper->consumeGesture(gesture);
	}

	uint32_t gesturesButtonToMotionEventButton(uint32_t gesturesButton) {
	switch (gesturesButton) {
	case GESTURES_BUTTON_LEFT:
	return AMOTION_EVENT_BUTTON_PRIMARY;
	case GESTURES_BUTTON_MIDDLE:
	return AMOTION_EVENT_BUTTON_TERTIARY;
	case GESTURES_BUTTON_RIGHT:
	return AMOTION_EVENT_BUTTON_SECONDARY;
	case GESTURES_BUTTON_BACK:
	return AMOTION_EVENT_BUTTON_BACK;
	case GESTURES_BUTTON_FORWARD:
	return AMOTION_EVENT_BUTTON_FORWARD;
	default:
	return 0;
	}
	}

	} // namespace

	TouchpadInputMapper::TouchpadInputMapper(InputDeviceContext& deviceContext)
	: InputMapper(deviceContext),
	mGestureInterpreter(NewGestureInterpreter(), DeleteGestureInterpreter),
	mPointerController(getContext()->getPointerController(getDeviceId())),
	mStateConverter(deviceContext) {
	mGestureInterpreter->Initialize(GESTURES_DEVCLASS_TOUCHPAD);
	mGestureInterpreter->SetHardwareProperties(createHardwareProperties(deviceContext));
	// Even though we don't explicitly delete copy/move semantics, it's safe to
	// give away a pointer to TouchpadInputMapper here because
	// 1) mGestureInterpreter's lifecycle is determined by TouchpadInputMapper, and
	// 2) TouchpadInputMapper is stored as a unique_ptr and not moved.
	mGestureInterpreter->SetCallback(gestureInterpreterCallback, this);
	// TODO(b/251196347): set a property provider, so we can change gesture properties.
	// TODO(b/251196347): set a timer provider, so the library can use timers.
	}

	TouchpadInputMapper::~TouchpadInputMapper() {
	if (mPointerController != nullptr) {
	mPointerController->fade(PointerControllerInterface::Transition::IMMEDIATE);
	}
	}

	uint32_t TouchpadInputMapper::getSources() const {
	return AINPUT_SOURCE_MOUSE \| AINPUT_SOURCE_TOUCHPAD;
	}

	std::list<NotifyArgs> TouchpadInputMapper::reset(nsecs_t when) {
	mStateConverter.reset();

	mButtonState = 0;
	return InputMapper::reset(when);
	}

	std::list<NotifyArgs> TouchpadInputMapper::process(const RawEvent* rawEvent) {
	std::optional<SelfContainedHardwareState> state = mStateConverter.processRawEvent(rawEvent);
	if (state) {
	return sendHardwareState(rawEvent->when, rawEvent->readTime, *state);
	} else {
	return {};
	}
	}

	std::list<NotifyArgs> TouchpadInputMapper::sendHardwareState(nsecs_t when, nsecs_t readTime,
	SelfContainedHardwareState schs) {
	mProcessing = true;
	mGestureInterpreter->PushHardwareState(&schs.state);
	mProcessing = false;

	return processGestures(when, readTime);
	}

	void TouchpadInputMapper::consumeGesture(const Gesture* gesture) {
	ALOGD("Gesture ready: %s", gesture->String().c_str());
	if (!mProcessing) {
	ALOGE("Received gesture outside of the normal processing flow; ignoring it.");
	return;
	}
	mGesturesToProcess.push_back(*gesture);
	}

	std::list<NotifyArgs> TouchpadInputMapper::processGestures(nsecs_t when, nsecs_t readTime) {
	std::list<NotifyArgs> out = {};
	for (Gesture& gesture : mGesturesToProcess) {
	switch (gesture.type) {
	case kGestureTypeMove:
	out.push_back(handleMove(when, readTime, gesture));
	break;
	case kGestureTypeButtonsChange:
	out += handleButtonsChange(when, readTime, gesture);
	break;
	default:
	// TODO(b/251196347): handle more gesture types.
	break;
	}
	}
	mGesturesToProcess.clear();
	return out;
	}

	NotifyArgs TouchpadInputMapper::handleMove(nsecs_t when, nsecs_t readTime, const Gesture& gesture) {
	PointerProperties props;
	props.clear();
	props.id = 0;
	props.toolType = AMOTION_EVENT_TOOL_TYPE_FINGER;

	mPointerController->setPresentation(PointerControllerInterface::Presentation::POINTER);
	mPointerController->move(gesture.details.move.dx, gesture.details.move.dy);
	mPointerController->unfade(PointerControllerInterface::Transition::IMMEDIATE);
	float xCursorPosition, yCursorPosition;
	mPointerController->getPosition(&xCursorPosition, &yCursorPosition);

	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, gesture.details.move.dx);
	coords.setAxisValue(AMOTION_EVENT_AXIS_RELATIVE_Y, gesture.details.move.dy);
	const bool down = isPointerDown(mButtonState);
	coords.setAxisValue(AMOTION_EVENT_AXIS_PRESSURE, down ? 1.0f : 0.0f);

	const int32_t action = down ? AMOTION_EVENT_ACTION_MOVE : AMOTION_EVENT_ACTION_HOVER_MOVE;
	return makeMotionArgs(when, readTime, action, /* actionButton= */ 0, mButtonState,
	/* pointerCount= */ 1, &props, &coords, xCursorPosition, yCursorPosition);
	}

	std::list<NotifyArgs> TouchpadInputMapper::handleButtonsChange(nsecs_t when, nsecs_t readTime,
	const Gesture& gesture) {
	std::list<NotifyArgs> out = {};

	mPointerController->setPresentation(PointerControllerInterface::Presentation::POINTER);
	mPointerController->unfade(PointerControllerInterface::Transition::IMMEDIATE);

	PointerProperties props;
	props.clear();
	props.id = 0;
	props.toolType = AMOTION_EVENT_TOOL_TYPE_FINGER;

	float xCursorPosition, yCursorPosition;
	mPointerController->getPosition(&xCursorPosition, &yCursorPosition);

	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 uint32_t buttonsPressed = gesture.details.buttons.down;
	bool pointerDown = isPointerDown(mButtonState) \|\|
	buttonsPressed &
	(GESTURES_BUTTON_LEFT \| GESTURES_BUTTON_MIDDLE \| GESTURES_BUTTON_RIGHT);
	coords.setAxisValue(AMOTION_EVENT_AXIS_PRESSURE, pointerDown ? 1.0f : 0.0f);

	uint32_t newButtonState = mButtonState;
	std::list<NotifyArgs> pressEvents = {};
	for (uint32_t button = 1; button <= GESTURES_BUTTON_FORWARD; button <<= 1) {
	if (buttonsPressed & button) {
	uint32_t actionButton = gesturesButtonToMotionEventButton(button);
	newButtonState \|= actionButton;
	pressEvents.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_BUTTON_PRESS,
	actionButton, newButtonState,
	/* pointerCount= */ 1, &props, &coords,
	xCursorPosition, yCursorPosition));
	}
	}
	if (!isPointerDown(mButtonState) && isPointerDown(newButtonState)) {
	mDownTime = when;
	out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_DOWN,
	/* actionButton= / 0, newButtonState, / pointerCount= */ 1,
	&props, &coords, xCursorPosition, yCursorPosition));
	}
	out.splice(out.end(), pressEvents);

	// The same button may be in both down and up in the same gesture, in which case we should treat
	// it as having gone down and then up. So, we treat a single button change gesture as two state
	// 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);
	newButtonState &= ~actionButton;
	out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_BUTTON_RELEASE,
	actionButton, newButtonState, /* pointerCount= */ 1,
	&props, &coords, xCursorPosition, yCursorPosition));
	}
	}
	if (isPointerDown(mButtonState) && !isPointerDown(newButtonState)) {
	coords.setAxisValue(AMOTION_EVENT_AXIS_PRESSURE, 0.0f);
	out.push_back(makeMotionArgs(when, readTime, AMOTION_EVENT_ACTION_UP, /* actionButton= */ 0,
	newButtonState, /* pointerCount= */ 1, &props, &coords,
	xCursorPosition, yCursorPosition));
	}
	mButtonState = newButtonState;
	return out;
	}

	NotifyMotionArgs TouchpadInputMapper::makeMotionArgs(nsecs_t when, nsecs_t readTime, int32_t action,
	int32_t actionButton, int32_t buttonState,
	uint32_t pointerCount,
	const PointerProperties* pointerProperties,
	const PointerCoords* pointerCoords,
	float xCursorPosition, float yCursorPosition) {
	// TODO(b/260226362): consider what the appropriate source for these events is.
	const uint32_t source = AINPUT_SOURCE_MOUSE;

	return NotifyMotionArgs(getContext()->getNextId(), when, readTime, getDeviceId(), source,
	mPointerController->getDisplayId(), /* policyFlags= */ 0, action,
	/* actionButton= / actionButton, / flags= */ 0,
	getContext()->getGlobalMetaState(), buttonState,
	MotionClassification::NONE, AMOTION_EVENT_EDGE_FLAG_NONE, pointerCount,
	pointerProperties, pointerCoords,
	/* xPrecision= / 1.0f, / yPrecision= */ 1.0f, xCursorPosition,
	yCursorPosition, /* downTime= / mDownTime, / videoFrames= */ {});
	}

	} // namespace android