ebiten/internal/gamepad/gamepad_linux.go
Hajime Hoshi b7dd45c0e4 internal/gamepad: ignore the very first MotionEvent with 0 value for Android
On Android, MotionEvent with 0 values might come for axes when connecting
a gamepad, even though a user didn't touch any axes. This is problematic
especially for tirgger axes, where the default value should be -1.

This change fixes the issue by adding a new state `axesReady` to check
if an axis is really touched or not. If an axis is not touched yet,
a button value for a standard (trigger) button always returns 0.

This change also removes an old hack to initialize axis values for
triggers.

Closes #2598
2024-03-21 22:28:48 +09:00

630 lines
18 KiB
Go

// Copyright 2022 The Ebiten Authors
//
// 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.
//go:build !android && !nintendosdk && !playstation5
package gamepad
import (
"fmt"
"os"
"path/filepath"
"regexp"
"runtime"
"time"
"unsafe"
"golang.org/x/sys/unix"
"github.com/hajimehoshi/ebiten/v2/internal/gamepaddb"
)
const dirName = "/dev/input"
var reEvent = regexp.MustCompile(`^event[0-9]+$`)
func isBitSet(s []byte, bit int) bool {
return s[bit/8]&(1<<(bit%8)) != 0
}
type nativeGamepadsImpl struct {
inotify int
watch int
}
func newNativeGamepadsImpl() nativeGamepads {
return &nativeGamepadsImpl{}
}
func (g *nativeGamepadsImpl) init(gamepads *gamepads) error {
// Check the existence of the directory `dirName`.
var stat unix.Stat_t
if err := unix.Stat(dirName, &stat); err != nil {
if err == unix.ENOENT {
return nil
}
return fmt.Errorf("gamepad: Stat failed: %w", err)
}
if stat.Mode&unix.S_IFDIR == 0 {
return nil
}
inotify, err := unix.InotifyInit1(unix.IN_NONBLOCK | unix.IN_CLOEXEC)
if err != nil {
return fmt.Errorf("gamepad: InotifyInit1 failed: %w", err)
}
g.inotify = inotify
if g.inotify > 0 {
// Register for IN_ATTRIB to get notified when udev is done.
// This works well in practice but the true way is libudev.
watch, err := unix.InotifyAddWatch(g.inotify, dirName, unix.IN_CREATE|unix.IN_ATTRIB|unix.IN_DELETE)
if err != nil {
return fmt.Errorf("gamepad: InotifyAddWatch failed: %w", err)
}
g.watch = watch
}
ents, err := os.ReadDir(dirName)
if err != nil {
return fmt.Errorf("gamepad: ReadDir(%s) failed: %w", dirName, err)
}
for _, ent := range ents {
if ent.IsDir() {
continue
}
if !reEvent.MatchString(ent.Name()) {
continue
}
if err := g.openGamepad(gamepads, filepath.Join(dirName, ent.Name())); err != nil {
return err
}
}
return nil
}
func (*nativeGamepadsImpl) openGamepad(gamepads *gamepads, path string) (err error) {
if gamepads.find(func(gamepad *Gamepad) bool {
return gamepad.native.(*nativeGamepadImpl).path == path
}) != nil {
return nil
}
fd, err := unix.Open(path, unix.O_RDONLY|unix.O_NONBLOCK, 0)
if err != nil {
if err == unix.EACCES {
return nil
}
// This happens with the Snap sandbox.
if err == unix.EPERM {
return nil
}
// This happens just after a disconnection.
if err == unix.ENOENT {
return nil
}
return fmt.Errorf("gamepad: Open failed: %w", err)
}
defer func() {
if err != nil {
_ = unix.Close(fd)
}
}()
evBits := make([]byte, (unix.EV_CNT+7)/8)
keyBits := make([]byte, (_KEY_CNT+7)/8)
absBits := make([]byte, (_ABS_CNT+7)/8)
var id input_id
if err := ioctl(fd, _EVIOCGBIT(0, uint(len(evBits))), unsafe.Pointer(&evBits[0])); err != nil {
return fmt.Errorf("gamepad: ioctl for evBits failed: %w", err)
}
if err := ioctl(fd, _EVIOCGBIT(unix.EV_KEY, uint(len(keyBits))), unsafe.Pointer(&keyBits[0])); err != nil {
return fmt.Errorf("gamepad: ioctl for keyBits failed: %w", err)
}
if err := ioctl(fd, _EVIOCGBIT(unix.EV_ABS, uint(len(absBits))), unsafe.Pointer(&absBits[0])); err != nil {
return fmt.Errorf("gamepad: ioctl for absBits failed: %w", err)
}
if err := ioctl(fd, _EVIOCGID(), unsafe.Pointer(&id)); err != nil {
return fmt.Errorf("gamepad: ioctl for an ID failed: %w", err)
}
if !isBitSet(evBits, unix.EV_KEY) {
if err := unix.Close(fd); err != nil {
return err
}
return nil
}
if !isBitSet(evBits, unix.EV_ABS) {
if err := unix.Close(fd); err != nil {
return err
}
return nil
}
cname := make([]byte, 256)
name := "Unknown"
// TODO: Is it OK to ignore the error here?
if err := ioctl(fd, uint(_EVIOCGNAME(uint(len(cname)))), unsafe.Pointer(&cname[0])); err == nil {
name = unix.ByteSliceToString(cname)
}
var sdlID string
if id.vendor != 0 && id.product != 0 && id.version != 0 {
sdlID = fmt.Sprintf("%02x%02x0000%02x%02x0000%02x%02x0000%02x%02x0000",
byte(id.bustype), byte(id.bustype>>8),
byte(id.vendor), byte(id.vendor>>8),
byte(id.product), byte(id.product>>8),
byte(id.version), byte(id.version>>8))
} else {
bs := []byte(name)
if len(bs) < 12 {
bs = append(bs, make([]byte, 12-len(bs))...)
}
sdlID = fmt.Sprintf("%02x%02x0000%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",
byte(id.bustype), byte(id.bustype>>8),
bs[0], bs[1], bs[2], bs[3], bs[4], bs[5], bs[6], bs[7], bs[8], bs[9], bs[10], bs[11])
}
n := &nativeGamepadImpl{
path: path,
fd: fd,
}
gp := gamepads.add(name, sdlID)
gp.native = n
runtime.SetFinalizer(gp, func(gp *Gamepad) {
n.close()
})
var axisCount int
var buttonCount int
var hatCount int
for i := range n.keyMap {
n.keyMap[i] = -1
}
for i := range n.absMap {
n.absMap[i] = -1
}
for code := _BTN_MISC; code < _KEY_CNT; code++ {
if !isBitSet(keyBits, code) {
continue
}
n.keyMap[code-_BTN_MISC] = buttonCount
buttonCount++
}
for code := 0; code < _ABS_CNT; code++ {
if !isBitSet(absBits, code) {
continue
}
if code >= _ABS_HAT0X && code <= _ABS_HAT3Y {
// Write the hat index both for the X and the Y hat axis.
// That way, the hat can be referenced using either axis, which is used by the code building hatMappingInput.
n.absMap[code] = hatCount
code++
n.absMap[code] = hatCount
hatCount++
continue
}
if err := ioctl(n.fd, uint(_EVIOCGABS(uint(code))), unsafe.Pointer(&n.absInfo[code])); err != nil {
return fmt.Errorf("gamepad: ioctl for an abs at openGamepad failed: %w", err)
}
n.absMap[code] = axisCount
axisCount++
}
n.axisCount_ = axisCount
n.buttonCount_ = buttonCount
n.hatCount_ = hatCount
n.computeStandardLayout(id.vendor)
if err := n.pollAbsState(); err != nil {
return err
}
return nil
}
func (g *nativeGamepadsImpl) update(gamepads *gamepads) error {
if g.inotify <= 0 {
return nil
}
buf := make([]byte, 16384)
n, err := unix.Read(g.inotify, buf[:])
if err != nil {
if err == unix.EAGAIN {
return nil
}
return fmt.Errorf("gamepad: Read failed: %w", err)
}
buf = buf[:n]
for len(buf) > 0 {
e := unix.InotifyEvent{
Wd: int32(buf[0]) | int32(buf[1])<<8 | int32(buf[2])<<16 | int32(buf[3])<<24,
Mask: uint32(buf[4]) | uint32(buf[5])<<8 | uint32(buf[6])<<16 | uint32(buf[7])<<24,
Cookie: uint32(buf[8]) | uint32(buf[9])<<8 | uint32(buf[10])<<16 | uint32(buf[11])<<24,
Len: uint32(buf[12]) | uint32(buf[13])<<8 | uint32(buf[14])<<16 | uint32(buf[15])<<24,
}
name := unix.ByteSliceToString(buf[16 : 16+e.Len-1]) // len includes the null terminate.
buf = buf[16+e.Len:]
if !reEvent.MatchString(name) {
continue
}
path := filepath.Join(dirName, name)
if e.Mask&(unix.IN_CREATE|unix.IN_ATTRIB) != 0 {
if err := g.openGamepad(gamepads, path); err != nil {
return err
}
continue
}
if e.Mask&unix.IN_DELETE != 0 {
if gp := gamepads.find(func(gamepad *Gamepad) bool {
return gamepad.native.(*nativeGamepadImpl).path == path
}); gp != nil {
gp.native.(*nativeGamepadImpl).close()
gamepads.remove(func(gamepad *Gamepad) bool {
return gamepad == gp
})
}
continue
}
}
return nil
}
type nativeGamepadImpl struct {
fd int
path string
keyMap [_KEY_CNT - _BTN_MISC]int
absMap [_ABS_CNT]int
absInfo [_ABS_CNT]input_absinfo
dropped bool
axes [_ABS_CNT]float64
buttons [_KEY_CNT - _BTN_MISC]bool
hats [4]int
axisCount_ int
buttonCount_ int
hatCount_ int
stdAxisMap map[gamepaddb.StandardAxis]mappingInput
stdButtonMap map[gamepaddb.StandardButton]mappingInput
}
func (g *nativeGamepadImpl) close() {
if g.fd != 0 {
_ = unix.Close(g.fd)
}
g.fd = 0
}
func (g *nativeGamepadImpl) update(gamepad *gamepads) error {
if g.fd == 0 {
return nil
}
for {
buf := make([]byte, unsafe.Sizeof(input_event{}))
// TODO: Should the returned byte count be cared?
if _, err := unix.Read(g.fd, buf); err != nil {
if err == unix.EAGAIN {
break
}
// Disconnected
if err == unix.ENODEV {
g.close()
return nil
}
return fmt.Errorf("gamepad: Read failed: %w", err)
}
const (
offsetTyp = unsafe.Offsetof(input_event{}.typ)
offsetCode = unsafe.Offsetof(input_event{}.code)
offsetValue = unsafe.Offsetof(input_event{}.value)
)
// time is not used.
e := input_event{
typ: uint16(buf[offsetTyp]) | uint16(buf[offsetTyp+1])<<8,
code: uint16(buf[offsetCode]) | uint16(buf[offsetCode+1])<<8,
value: int32(buf[offsetValue]) | int32(buf[offsetValue+1])<<8 | int32(buf[offsetValue+2])<<16 | int32(buf[offsetValue+3])<<24,
}
if e.typ == unix.EV_SYN {
switch e.code {
case _SYN_DROPPED:
g.dropped = true
case _SYN_REPORT:
g.dropped = false
if err := g.pollAbsState(); err != nil {
return fmt.Errorf("gamepad: poll absolute state: %w", err)
}
}
}
if g.dropped {
continue
}
switch e.typ {
case unix.EV_KEY:
if int(e.code-_BTN_MISC) < len(g.keyMap) {
idx := g.keyMap[e.code-_BTN_MISC]
if idx < 0 {
continue
}
g.buttons[idx] = e.value != 0
}
case unix.EV_ABS:
g.handleAbsEvent(int(e.code), e.value)
}
}
return nil
}
func (g *nativeGamepadImpl) pollAbsState() error {
for code := 0; code < _ABS_CNT; code++ {
if g.absMap[code] < 0 {
continue
}
if err := ioctl(g.fd, uint(_EVIOCGABS(uint(code))), unsafe.Pointer(&g.absInfo[code])); err != nil {
return fmt.Errorf("gamepad: ioctl for an abs at pollAbsState failed: %w", err)
}
g.handleAbsEvent(code, g.absInfo[code].value)
}
return nil
}
func (g *nativeGamepadImpl) handleAbsEvent(code int, value int32) {
index := g.absMap[code]
if index < 0 {
return
}
if code >= _ABS_HAT0X && code <= _ABS_HAT3Y {
axis := (code - _ABS_HAT0X) % 2
switch axis {
case 0:
switch {
case value < 0:
g.hats[index] |= hatLeft
g.hats[index] &^= hatRight
case value > 0:
g.hats[index] &^= hatLeft
g.hats[index] |= hatRight
default:
g.hats[index] &^= hatLeft | hatRight
}
case 1:
switch {
case value < 0:
g.hats[index] |= hatUp
g.hats[index] &^= hatDown
case value > 0:
g.hats[index] &^= hatUp
g.hats[index] |= hatDown
default:
g.hats[index] &^= hatUp | hatDown
}
}
return
}
info := g.absInfo[code]
v := float64(value)
if r := float64(info.maximum) - float64(info.minimum); r != 0 {
v = (v - float64(info.minimum)) / r
v = v*2 - 1
}
g.axes[index] = v
}
func (g *nativeGamepadImpl) computeStandardLayout(vendor uint16) {
g.stdAxisMap = map[gamepaddb.StandardAxis]mappingInput{}
g.stdButtonMap = map[gamepaddb.StandardButton]mappingInput{}
// NOTE: assignments to the same value are in exact reverse order as SDL2,
// so we can just overwrite rather than checking.
// BTN_GAMEPAD implies that the kernel module implements standard mapping.
if b := g.keyMap[_BTN_GAMEPAD-_BTN_MISC]; b < 0 {
return
}
// A and B buttons go by name.
if b := g.keyMap[_BTN_A-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonRightBottom] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_B-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonRightRight] = buttonMappingInput{g: g, button: b}
}
if vendor == 0x054c /* USB_VENDOR_SONY */ {
// Sony uses WEST/NORTH buttons.
if b := g.keyMap[_BTN_WEST-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonRightLeft] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_NORTH-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonRightTop] = buttonMappingInput{g: g, button: b}
}
} else {
// Xbox uses X/Y buttons.
// Note that this is the opposite assignment following the WEST/NORTH mappings,
// and contradicts Linux kernel documentation which states
// that buttons are always assigned by physical location.
// However, it matches actual Xbox gamepads, and SDL2 has the same logic.
if b := g.keyMap[_BTN_X-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonRightLeft] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_Y-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonRightTop] = buttonMappingInput{g: g, button: b}
}
}
// Center and thumb buttons.
if b := g.keyMap[_BTN_SELECT-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonCenterLeft] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_START-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonCenterRight] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_THUMBL-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonLeftStick] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_THUMBR-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonRightStick] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_MODE-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonCenterCenter] = buttonMappingInput{g: g, button: b}
}
// Shoulder buttons can be analog or digital. Prefer digital ones.
if h := g.absMap[_ABS_HAT1Y]; h >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonFrontTopLeft] = hatMappingInput{g: g, hat: h, direction: hatDown}
}
if h := g.absMap[_ABS_HAT1X]; h >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonFrontTopRight] = hatMappingInput{g: g, hat: h, direction: hatRight}
}
if b := g.keyMap[_BTN_TL-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonFrontTopLeft] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_TR-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonFrontTopRight] = buttonMappingInput{g: g, button: b}
}
// Triggers can be analog or digital. Prefer analog ones.
if b := g.keyMap[_BTN_TL2-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonFrontBottomLeft] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_TR2-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonFrontBottomRight] = buttonMappingInput{g: g, button: b}
}
if a := g.absMap[_ABS_Z]; a >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonFrontBottomLeft] = axisMappingInput{g: g, axis: a}
}
if a := g.absMap[_ABS_RZ]; a >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonFrontBottomRight] = axisMappingInput{g: g, axis: a}
}
if h := g.absMap[_ABS_HAT2Y]; h >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonFrontBottomLeft] = hatMappingInput{g: g, hat: h, direction: hatDown}
}
if h := g.absMap[_ABS_HAT2X]; h >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonFrontBottomRight] = hatMappingInput{g: g, hat: h, direction: hatRight}
}
// D-pad can be analog or digital. Prefer digital one.
if h := g.absMap[_ABS_HAT0X]; h >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonLeftLeft] = hatMappingInput{g: g, hat: h, direction: hatLeft}
g.stdButtonMap[gamepaddb.StandardButtonLeftRight] = hatMappingInput{g: g, hat: h, direction: hatRight}
}
if h := g.absMap[_ABS_HAT0Y]; h >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonLeftTop] = hatMappingInput{g: g, hat: h, direction: hatUp}
g.stdButtonMap[gamepaddb.StandardButtonLeftBottom] = hatMappingInput{g: g, hat: h, direction: hatDown}
}
if b := g.keyMap[_BTN_DPAD_UP-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonLeftTop] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_DPAD_DOWN-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonLeftBottom] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_DPAD_LEFT-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonLeftLeft] = buttonMappingInput{g: g, button: b}
}
if b := g.keyMap[_BTN_DPAD_RIGHT-_BTN_MISC]; b >= 0 {
g.stdButtonMap[gamepaddb.StandardButtonLeftRight] = buttonMappingInput{g: g, button: b}
}
// Left stick.
if a := g.absMap[_ABS_X]; a >= 0 {
g.stdAxisMap[gamepaddb.StandardAxisLeftStickHorizontal] = axisMappingInput{g: g, axis: a}
}
if a := g.absMap[_ABS_Y]; a >= 0 {
g.stdAxisMap[gamepaddb.StandardAxisLeftStickVertical] = axisMappingInput{g: g, axis: a}
}
// Right stick.
if a := g.absMap[_ABS_RX]; a >= 0 {
g.stdAxisMap[gamepaddb.StandardAxisRightStickHorizontal] = axisMappingInput{g: g, axis: a}
}
if a := g.absMap[_ABS_RY]; a >= 0 {
g.stdAxisMap[gamepaddb.StandardAxisRightStickVertical] = axisMappingInput{g: g, axis: a}
}
}
func (g *nativeGamepadImpl) hasOwnStandardLayoutMapping() bool {
return len(g.stdAxisMap) != 0 || len(g.stdButtonMap) != 0
}
func (g *nativeGamepadImpl) standardAxisInOwnMapping(axis gamepaddb.StandardAxis) mappingInput {
return g.stdAxisMap[axis]
}
func (g *nativeGamepadImpl) standardButtonInOwnMapping(button gamepaddb.StandardButton) mappingInput {
return g.stdButtonMap[button]
}
func (g *nativeGamepadImpl) axisCount() int {
return g.axisCount_
}
func (g *nativeGamepadImpl) buttonCount() int {
return g.buttonCount_
}
func (g *nativeGamepadImpl) hatCount() int {
return g.hatCount_
}
func (g *nativeGamepadImpl) isAxisReady(axis int) bool {
return axis >= 0 && axis < g.axisCount()
}
func (g *nativeGamepadImpl) axisValue(axis int) float64 {
if axis < 0 || axis >= g.axisCount_ {
return 0
}
return g.axes[axis]
}
func (g *nativeGamepadImpl) isButtonPressed(button int) bool {
if button < 0 || button >= g.buttonCount_ {
return false
}
return g.buttons[button]
}
func (g *nativeGamepadImpl) buttonValue(button int) float64 {
if g.isButtonPressed(button) {
return 1
}
return 0
}
func (g *nativeGamepadImpl) hatState(hat int) int {
if hat < 0 || hat >= g.hatCount_ {
return hatCentered
}
return g.hats[hat]
}
func (g *nativeGamepadImpl) vibrate(duration time.Duration, strongMagnitude float64, weakMagnitude float64) {
// TODO: Implement this (#1452)
}