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internal/gamepad: remove dependency on golang.org/x/sys/unix
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@hajimehoshi
hajimehoshi committed Oct 29, 2022
1 parent 90e2250 commit 046f7e5
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Showing 2 changed files with 50 additions and 39 deletions.
14 changes: 9 additions & 5 deletions internal/gamepad/api_linux.go
View file
Expand Up @@ -18,9 +18,8 @@
package gamepad

import (
"syscall"
"unsafe"

"golang.org/x/sys/unix"
)

const (
Expand All @@ -31,6 +30,11 @@ const (

_BTN_MISC = 0x100

_EV_ABS = 0x3
_EV_CNT = 0x20
_EV_KEY = 0x1
_EV_SYN = 0x0

_IOC_NONE = 0
_IOC_WRITE = 1
_IOC_READ = 2
Expand Down Expand Up @@ -86,7 +90,7 @@ type input_absinfo struct {
}

type input_event struct {
time unix.Timeval
time syscall.Timeval
typ uint16
code uint16
value int32
Expand All @@ -100,9 +104,9 @@ type input_id struct {
}

func ioctl(fd int, request uint, ptr unsafe.Pointer) error {
r, _, e := unix.Syscall(unix.SYS_IOCTL, uintptr(fd), uintptr(request), uintptr(ptr))
r, _, e := syscall.Syscall(syscall.SYS_IOCTL, uintptr(fd), uintptr(request), uintptr(ptr))
if r < 0 {
return unix.Errno(e)
return syscall.Errno(e)
}
return nil
}
75 changes: 41 additions & 34 deletions internal/gamepad/gamepad_linux.go
View file
Expand Up @@ -18,19 +18,26 @@
package gamepad

import (
"bytes"
"fmt"
"os"
"path/filepath"
"regexp"
"runtime"
"syscall"
"time"
"unsafe"

"golang.org/x/sys/unix"

"github.com/hajimehoshi/ebiten/v2/internal/gamepaddb"
)

func byteSliceToString(s []byte) string {
if i := bytes.IndexByte(s, 0); i != -1 {
s = s[:i]
}
return string(s)
}

const dirName = "/dev/input"

var reEvent = regexp.MustCompile(`^event[0-9]+$`)
Expand All @@ -50,18 +57,18 @@ func newNativeGamepadsImpl() nativeGamepads {

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 {
var stat syscall.Stat_t
if err := syscall.Stat(dirName, &stat); err != nil {
if err == syscall.ENOENT {
return nil
}
return fmt.Errorf("gamepad: Stat failed: %w", err)
}
if stat.Mode&unix.S_IFDIR == 0 {
if stat.Mode&syscall.S_IFDIR == 0 {
return nil
}

inotify, err := unix.InotifyInit1(unix.IN_NONBLOCK | unix.IN_CLOEXEC)
inotify, err := syscall.InotifyInit1(syscall.IN_NONBLOCK | syscall.IN_CLOEXEC)
if err != nil {
return fmt.Errorf("gamepad: InotifyInit1 failed: %w", err)
}
Expand All @@ -70,7 +77,7 @@ func (g *nativeGamepadsImpl) init(gamepads *gamepads) error {
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)
watch, err := syscall.InotifyAddWatch(g.inotify, dirName, syscall.IN_CREATE|syscall.IN_ATTRIB|syscall.IN_DELETE)
if err != nil {
return fmt.Errorf("gamepad: InotifyAddWatch failed: %w", err)
}
Expand Down Expand Up @@ -103,53 +110,53 @@ func (*nativeGamepadsImpl) openGamepad(gamepads *gamepads, path string) (err err
return nil
}

fd, err := unix.Open(path, unix.O_RDONLY|unix.O_NONBLOCK, 0)
fd, err := syscall.Open(path, syscall.O_RDONLY|syscall.O_NONBLOCK, 0)
if err != nil {
if err == unix.EACCES {
if err == syscall.EACCES {
return nil
}
// This happens with the Snap sandbox.
if err == unix.EPERM {
if err == syscall.EPERM {
return nil
}
// This happens just after a disconnection.
if err == unix.ENOENT {
if err == syscall.ENOENT {
return nil
}
return fmt.Errorf("gamepad: Open failed: %w", err)
}
defer func() {
if err != nil {
_ = unix.Close(fd)
_ = syscall.Close(fd)
}
}()

evBits := make([]byte, (unix.EV_CNT+7)/8)
evBits := make([]byte, (_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 {
if err := ioctl(fd, _EVIOCGBIT(_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 {
if err := ioctl(fd, _EVIOCGBIT(_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 {
if !isBitSet(evBits, _EV_KEY) {
if err := syscall.Close(fd); err != nil {
return err
}

return nil
}
if !isBitSet(evBits, unix.EV_ABS) {
if err := unix.Close(fd); err != nil {
if !isBitSet(evBits, _EV_ABS) {
if err := syscall.Close(fd); err != nil {
return err
}

Expand All @@ -160,7 +167,7 @@ func (*nativeGamepadsImpl) openGamepad(gamepads *gamepads, path string) (err err
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)
name = byteSliceToString(cname)
}

var sdlID string
Expand Down Expand Up @@ -236,36 +243,36 @@ func (g *nativeGamepadsImpl) update(gamepads *gamepads) error {
}

buf := make([]byte, 16384)
n, err := unix.Read(g.inotify, buf[:])
n, err := syscall.Read(g.inotify, buf[:])
if err != nil {
if err == unix.EAGAIN {
if err == syscall.EAGAIN {
return nil
}
return fmt.Errorf("gamepad: Read failed: %w", err)
}
buf = buf[:n]

for len(buf) > 0 {
e := unix.InotifyEvent{
e := syscall.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 termiinate.
name := byteSliceToString(buf[16 : 16+e.Len-1]) // len includes the null termiinate.
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 e.Mask&(syscall.IN_CREATE|syscall.IN_ATTRIB) != 0 {
if err := g.openGamepad(gamepads, path); err != nil {
return err
}
continue
}
if e.Mask&unix.IN_DELETE != 0 {
if e.Mask&syscall.IN_DELETE != 0 {
if gp := gamepads.find(func(gamepad *Gamepad) bool {
return gamepad.native.(*nativeGamepadImpl).path == path
}); gp != nil {
Expand Down Expand Up @@ -300,7 +307,7 @@ type nativeGamepadImpl struct {

func (g *nativeGamepadImpl) close() {
if g.fd != 0 {
_ = unix.Close(g.fd)
_ = syscall.Close(g.fd)
}
g.fd = 0
}
Expand All @@ -313,12 +320,12 @@ func (g *nativeGamepadImpl) update(gamepad *gamepads) error {
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 {
if _, err := syscall.Read(g.fd, buf); err != nil {
if err == syscall.EAGAIN {
break
}
// Disconnected
if err == unix.ENODEV {
if err == syscall.ENODEV {
g.close()
return nil
}
Expand All @@ -337,7 +344,7 @@ func (g *nativeGamepadImpl) update(gamepad *gamepads) error {
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 {
if e.typ == _EV_SYN {
switch e.code {
case _SYN_DROPPED:
g.dropped = true
Expand All @@ -353,12 +360,12 @@ func (g *nativeGamepadImpl) update(gamepad *gamepads) error {
}

switch e.typ {
case unix.EV_KEY:
case _EV_KEY:
if int(e.code-_BTN_MISC) < len(g.keyMap) {
idx := g.keyMap[e.code-_BTN_MISC]
g.buttons[idx] = e.value != 0
}
case unix.EV_ABS:
case _EV_ABS:
g.handleAbsEvent(int(e.code), e.value)
}
}
Expand Down

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