ObjFW  Check-in [8e95537be5]

Overview
Comment:OFEvdevGameController: Add support for polling

This is required to get the initial state and when events get dropped.

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Timelines: family | ancestors | descendants | both | gamecontroller
Files: files | file ages | folders
SHA3-256: 8e95537be5f2670efe266dab202a01d4f5297388d59e7d387efc96907e184ea8
User & Date: js on 2024-05-20 17:19:05
Other Links: branch diff | manifest | tags
Context
2024-05-20
17:21
Add ObjFWHID subframework with OFGameController check-in: d901707b57 user: js tags: trunk
17:19
OFEvdevGameController: Add support for polling Closed-Leaf check-in: 8e95537be5 user: js tags: gamecontroller
15:53
OFGameController: No symbols for custom buttons check-in: cb4c3d09f4 user: js tags: gamecontroller
Changes

Modified src/hid/OFEvdevGameController.h from [251f0edbf4] to [f6b3abc284].

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OF_ASSUME_NONNULL_BEGIN

@interface OFEvdevGameController: OFGameController
{
	OFString *_path;
	int _fd;


	uint16_t _vendorID, _productID;
	OFString *_name;
	OFMutableSet OF_GENERIC(OFGameControllerButton) *_buttons;
	OFMutableSet OF_GENERIC(OFGameControllerButton) *_pressedButtons;
	bool _hasLeftAnalogStick, _hasRightAnalogStick;
	bool _hasLeftTriggerPressure, _hasRightTriggerPressure;
	unsigned int _leftTriggerPressureBit, _rightTriggerPressureBit;
	OFPoint _leftAnalogStickPosition, _rightAnalogStickPosition;
	float _leftTriggerPressure, _rightTriggerPressure;
	int32_t _leftAnalogStickMinX, _leftAnalogStickMaxX;
	int32_t _leftAnalogStickMinY, _leftAnalogStickMaxY;
	unsigned int _rightAnalogStickXBit, _rightAnalogStickYBit;
	int32_t _rightAnalogStickMinX, _rightAnalogStickMaxX;
	int32_t _rightAnalogStickMinY, _rightAnalogStickMaxY;
	int32_t _leftTriggerMinPressure, _leftTriggerMaxPressure;
	int32_t _rightTriggerMinPressure, _rightTriggerMaxPressure;
}

- (instancetype)of_initWithPath: (OFString *)path OF_METHOD_FAMILY(init);

@end

OF_ASSUME_NONNULL_END







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OF_ASSUME_NONNULL_BEGIN

@interface OFEvdevGameController: OFGameController
{
	OFString *_path;
	int _fd;
	bool _discardUntilReport;
	unsigned long *_keyBits;
	uint16_t _vendorID, _productID;
	OFString *_name;
	OFMutableSet OF_GENERIC(OFGameControllerButton) *_buttons;
	OFMutableSet OF_GENERIC(OFGameControllerButton) *_pressedButtons;
	bool _hasLeftAnalogStick, _hasRightAnalogStick;
	bool _hasLeftTriggerPressure, _hasRightTriggerPressure;
	unsigned int _leftTriggerPressureBit, _rightTriggerPressureBit;
	OFPoint _leftAnalogStickPosition, _rightAnalogStickPosition;
	float _leftTriggerPressure, _rightTriggerPressure;
	int32_t _leftAnalogStickMinX, _leftAnalogStickMaxX;
	int32_t _leftAnalogStickMinY, _leftAnalogStickMaxY;
	unsigned int _rightAnalogStickXBit, _rightAnalogStickYBit;
	int32_t _rightAnalogStickMinX, _rightAnalogStickMaxX;
	int32_t _rightAnalogStickMinY, _rightAnalogStickMaxY;
	int32_t _leftTriggerMinPressure, _leftTriggerMaxPressure;
	int32_t _rightTriggerMinPressure, _rightTriggerMaxPressure;
}

- (instancetype)of_initWithPath: (OFString *)path OF_METHOD_FAMILY(init);
- (void)of_pollState;
@end

OF_ASSUME_NONNULL_END

Modified src/hid/OFEvdevGameController.m from [beaad493bb] to [5b6c618a19].

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{
	self = [super init];

	@try {
		OFStringEncoding encoding = [OFLocale encoding];
		unsigned long evBits[OFRoundUpToPowerOf2(OF_ULONG_BIT,
		    EV_MAX) / OF_ULONG_BIT] = { 0 };
		unsigned long keyBits[OFRoundUpToPowerOf2(OF_ULONG_BIT,
		    KEY_MAX) / OF_ULONG_BIT] = { 0 };
		unsigned long absBits[OFRoundUpToPowerOf2(OF_ULONG_BIT,
		    ABS_MAX) / OF_ULONG_BIT] = { 0 };
		struct input_id inputID;
		char name[128];

		_path = [path copy];

		if ((_fd = open([_path cStringWithEncoding: encoding],
		    O_RDONLY | O_NONBLOCK)) == -1)
			@throw [OFOpenItemFailedException
			    exceptionWithPath: _path
					 mode: @"r"
					errNo: errno];

		if (ioctl(_fd, EVIOCGBIT(0, sizeof(evBits)), evBits) == -1)
			@throw [OFInitializationFailedException exception];

		if (!OFBitSetIsSet(evBits, EV_KEY))
			@throw [OFInvalidArgumentException exception];




		if (ioctl(_fd, EVIOCGBIT(EV_KEY, sizeof(keyBits)), keyBits) ==

		    -1)
			@throw [OFInitializationFailedException exception];

		if (!OFBitSetIsSet(keyBits, BTN_GAMEPAD) &&
		    !OFBitSetIsSet(keyBits, BTN_DPAD_UP))
			@throw [OFInvalidArgumentException exception];

		if (ioctl(_fd, EVIOCGID, &inputID) == -1)
			@throw [OFInvalidArgumentException exception];

		_vendorID = inputID.vendor;
		_productID = inputID.product;

		if (ioctl(_fd, EVIOCGNAME(sizeof(name)), name) == -1)
			@throw [OFInitializationFailedException exception];

		_name = [[OFString alloc] initWithCString: name
						 encoding: encoding];

		_buttons = [[OFMutableSet alloc] init];
		for (size_t i = 0; i < sizeof(buttons) / sizeof(*buttons);
		    i++) {
			if (OFBitSetIsSet(keyBits, buttons[i])) {
				OFGameControllerButton button = buttonToName(
				    buttons[i], _vendorID, _productID);

				if (button != nil)
					[_buttons addObject: button];
			}
		}







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{
	self = [super init];

	@try {
		OFStringEncoding encoding = [OFLocale encoding];
		unsigned long evBits[OFRoundUpToPowerOf2(OF_ULONG_BIT,
		    EV_MAX) / OF_ULONG_BIT] = { 0 };


		unsigned long absBits[OFRoundUpToPowerOf2(OF_ULONG_BIT,
		    ABS_MAX) / OF_ULONG_BIT] = { 0 };
		struct input_id inputID;
		char name[128];

		_path = [path copy];

		if ((_fd = open([_path cStringWithEncoding: encoding],
		    O_RDONLY | O_NONBLOCK)) == -1)
			@throw [OFOpenItemFailedException
			    exceptionWithPath: _path
					 mode: @"r"
					errNo: errno];

		if (ioctl(_fd, EVIOCGBIT(0, sizeof(evBits)), evBits) == -1)
			@throw [OFInitializationFailedException exception];

		if (!OFBitSetIsSet(evBits, EV_KEY))
			@throw [OFInvalidArgumentException exception];

		_keyBits = OFAllocZeroedMemory(OFRoundUpToPowerOf2(OF_ULONG_BIT,
		    KEY_MAX) / OF_ULONG_BIT, sizeof(unsigned long));

		if (ioctl(_fd, EVIOCGBIT(EV_KEY, OFRoundUpToPowerOf2(
		    OF_ULONG_BIT, KEY_MAX) / OF_ULONG_BIT *
		    sizeof(unsigned long)), _keyBits) == -1)
			@throw [OFInitializationFailedException exception];

		if (!OFBitSetIsSet(_keyBits, BTN_GAMEPAD) &&
		    !OFBitSetIsSet(_keyBits, BTN_DPAD_UP))
			@throw [OFInvalidArgumentException exception];

		if (ioctl(_fd, EVIOCGID, &inputID) == -1)
			@throw [OFInvalidArgumentException exception];

		_vendorID = inputID.vendor;
		_productID = inputID.product;

		if (ioctl(_fd, EVIOCGNAME(sizeof(name)), name) == -1)
			@throw [OFInitializationFailedException exception];

		_name = [[OFString alloc] initWithCString: name
						 encoding: encoding];

		_buttons = [[OFMutableSet alloc] init];
		for (size_t i = 0; i < sizeof(buttons) / sizeof(*buttons);
		    i++) {
			if (OFBitSetIsSet(_keyBits, buttons[i])) {
				OFGameControllerButton button = buttonToName(
				    buttons[i], _vendorID, _productID);

				if (button != nil)
					[_buttons addObject: button];
			}
		}
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				_rightAnalogStickXBit = ABS_RX;
				_rightAnalogStickYBit = ABS_RY;
				_leftTriggerPressureBit = ABS_Z;
				_rightTriggerPressureBit = ABS_RZ;
			}

			if (OFBitSetIsSet(absBits, ABS_X) &&
			    OFBitSetIsSet(absBits, ABS_Y)) {
				struct input_absinfo infoX, infoY;

				_hasLeftAnalogStick = true;

				if (ioctl(_fd, EVIOCGABS(ABS_X), &infoX) == -1)
					@throw [OFInitializationFailedException
					    exception];

				if (ioctl(_fd, EVIOCGABS(ABS_Y), &infoY) == -1)
					@throw [OFInitializationFailedException
					    exception];

				_leftAnalogStickMinX = infoX.minimum;
				_leftAnalogStickMaxX = infoX.maximum;
				_leftAnalogStickMinY = infoY.minimum;
				_leftAnalogStickMaxY = infoY.maximum;
			}

			if (OFBitSetIsSet(absBits, _rightAnalogStickXBit) &&
			    OFBitSetIsSet(absBits, _rightAnalogStickYBit)) {
				struct input_absinfo infoX, infoY;

				_hasRightAnalogStick = true;

				if (ioctl(_fd, EVIOCGABS(_rightAnalogStickXBit),
				    &infoX) == -1)
					@throw [OFInitializationFailedException
					    exception];

				if (ioctl(_fd, EVIOCGABS(_rightAnalogStickYBit),
				    &infoY) == -1)
					@throw [OFInitializationFailedException
					    exception];

				_rightAnalogStickMinX = infoX.minimum;
				_rightAnalogStickMaxX = infoX.maximum;
				_rightAnalogStickMinY = infoY.minimum;
				_rightAnalogStickMaxY = infoY.maximum;
			}

			if (_vendorID == vendorIDNintendo &&
			    _productID == productIDN64Controller &&
			    OFBitSetIsSet(keyBits, BTN_Y) &&
			    OFBitSetIsSet(keyBits, BTN_C) &&
			    OFBitSetIsSet(keyBits, BTN_SELECT) &&
			    OFBitSetIsSet(keyBits, BTN_X))
				_hasRightAnalogStick = true;

			if (OFBitSetIsSet(absBits, ABS_HAT0X) &&
			    OFBitSetIsSet(absBits, ABS_HAT0Y)) {
				[_buttons addObject:
				    OFGameControllerDPadLeftButton];
				[_buttons addObject:
				    OFGameControllerDPadRightButton];
				[_buttons addObject:
				    OFGameControllerDPadUpButton];
				[_buttons addObject:
				    OFGameControllerDPadDownButton];
			}

			if (OFBitSetIsSet(absBits, _leftTriggerPressureBit)) {
				struct input_absinfo info;

				_hasLeftTriggerPressure = true;

				if (ioctl(_fd, EVIOCGABS(
				    _leftTriggerPressureBit), &info) == -1)
					@throw [OFInitializationFailedException
					    exception];

				_leftTriggerMinPressure = info.minimum;
				_leftTriggerMaxPressure = info.maximum;

				[_buttons addObject:
				    OFGameControllerLeftTriggerButton];
			}

			if (OFBitSetIsSet(absBits, _rightTriggerPressureBit)) {
				struct input_absinfo info;

				_hasRightTriggerPressure = true;

				if (ioctl(_fd, EVIOCGABS(
				    _rightTriggerPressureBit), &info) == -1)
					@throw [OFInitializationFailedException
					    exception];

				_rightTriggerMinPressure = info.minimum;
				_rightTriggerMaxPressure = info.maximum;

				[_buttons addObject:
				    OFGameControllerRightTriggerButton];
			}
		}

		[_buttons makeImmutable];


		[self retrieveState];



	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	[_path release];

	if (_fd != -1)
		close(_fd);



	[_name release];
	[_buttons release];
	[_pressedButtons release];

	[super dealloc];
}

- (OFNumber *)vendorID
{
	return [OFNumber numberWithUnsignedShort: _vendorID];
}

- (OFNumber *)productID
{
	return [OFNumber numberWithUnsignedShort: _productID];
}

























































































































- (void)retrieveState
{
	struct input_event event;

	for (;;) {
		OFGameControllerButton button;

		errno = 0;

		if (read(_fd, &event, sizeof(event)) < (int)sizeof(event)) {
			if (errno == EWOULDBLOCK)
				return;

			@throw [OFReadFailedException
			    exceptionWithObject: self
				requestedLength: sizeof(event)
					  errNo: errno];
		}










		switch (event.type) {






		case EV_KEY:
			if ((button = buttonToName(event.code, _vendorID,
			    _productID)) != nil) {
				if (event.value)
					[_pressedButtons addObject: button];
				else
					[_pressedButtons removeObject: button];







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				_rightAnalogStickXBit = ABS_RX;
				_rightAnalogStickYBit = ABS_RY;
				_leftTriggerPressureBit = ABS_Z;
				_rightTriggerPressureBit = ABS_RZ;
			}

			if (OFBitSetIsSet(absBits, ABS_X) &&
			    OFBitSetIsSet(absBits, ABS_Y))


				_hasLeftAnalogStick = true;















			if (OFBitSetIsSet(absBits, _rightAnalogStickXBit) &&
			    OFBitSetIsSet(absBits, _rightAnalogStickYBit))


				_hasRightAnalogStick = true;

















			if (_vendorID == vendorIDNintendo &&
			    _productID == productIDN64Controller &&
			    OFBitSetIsSet(_keyBits, BTN_Y) &&
			    OFBitSetIsSet(_keyBits, BTN_C) &&
			    OFBitSetIsSet(_keyBits, BTN_SELECT) &&
			    OFBitSetIsSet(_keyBits, BTN_X))
				_hasRightAnalogStick = true;

			if (OFBitSetIsSet(absBits, ABS_HAT0X) &&
			    OFBitSetIsSet(absBits, ABS_HAT0Y)) {
				[_buttons addObject:
				    OFGameControllerDPadLeftButton];
				[_buttons addObject:
				    OFGameControllerDPadRightButton];
				[_buttons addObject:
				    OFGameControllerDPadUpButton];
				[_buttons addObject:
				    OFGameControllerDPadDownButton];
			}

			if (OFBitSetIsSet(absBits, _leftTriggerPressureBit)) {


				_hasLeftTriggerPressure = true;









				[_buttons addObject:
				    OFGameControllerLeftTriggerButton];
			}

			if (OFBitSetIsSet(absBits, _rightTriggerPressureBit)) {


				_hasRightTriggerPressure = true;









				[_buttons addObject:
				    OFGameControllerRightTriggerButton];
			}
		}

		[_buttons makeImmutable];

		@try {
			[self of_pollState];
		} @catch (OFReadFailedException *e) {
			@throw [OFInitializationFailedException exception];
		}
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	[_path release];

	if (_fd != -1)
		close(_fd);

	OFFreeMemory(_keyBits);

	[_name release];
	[_buttons release];
	[_pressedButtons release];

	[super dealloc];
}

- (OFNumber *)vendorID
{
	return [OFNumber numberWithUnsignedShort: _vendorID];
}

- (OFNumber *)productID
{
	return [OFNumber numberWithUnsignedShort: _productID];
}

- (void)of_pollState
{
	unsigned long keyState[OFRoundUpToPowerOf2(OF_ULONG_BIT, KEY_MAX) /
	    OF_ULONG_BIT] = { 0 };

	if (ioctl(_fd, EVIOCGKEY(sizeof(keyState)), &keyState) == -1)
		@throw [OFReadFailedException
		    exceptionWithObject: self
			requestedLength: sizeof(keyState)
				  errNo: errno];

	[_pressedButtons removeAllObjects];

	for (size_t i = 0; i < sizeof(buttons) / sizeof(*buttons);
	    i++) {
		if (OFBitSetIsSet(_keyBits, buttons[i]) &&
		    OFBitSetIsSet(keyState, buttons[i])) {
			OFGameControllerButton button = buttonToName(
			    buttons[i], _vendorID, _productID);

			if (button != nil)
				[_pressedButtons addObject: button];
		}
	}

	if (_hasLeftAnalogStick) {
		struct input_absinfo infoX, infoY;

		if (ioctl(_fd, EVIOCGABS(ABS_X), &infoX) == -1)
			@throw [OFReadFailedException
			    exceptionWithObject: self
				requestedLength: sizeof(infoX)
					  errNo: errno];

		if (ioctl(_fd, EVIOCGABS(ABS_Y), &infoY) == -1)
			@throw [OFReadFailedException
			    exceptionWithObject: self
				requestedLength: sizeof(infoY)
					  errNo: errno];

		_leftAnalogStickMinX = infoX.minimum;
		_leftAnalogStickMaxX = infoX.maximum;
		_leftAnalogStickMinY = infoY.minimum;
		_leftAnalogStickMaxY = infoY.maximum;
		_leftAnalogStickPosition.x = scale(infoX.value,
		    _leftAnalogStickMinX, _leftAnalogStickMaxX);
		_leftAnalogStickPosition.y = scale(infoY.value,
		    _leftAnalogStickMinY, _leftAnalogStickMaxY);
	}

	if (_vendorID == vendorIDNintendo &&
	    _productID == productIDN64Controller &&
	    OFBitSetIsSet(_keyBits, BTN_Y) && OFBitSetIsSet(_keyBits, BTN_C) &&
	    OFBitSetIsSet(_keyBits, BTN_SELECT) &&
	    OFBitSetIsSet(_keyBits, BTN_X))
		_rightAnalogStickPosition = OFMakePoint(
		    -OFBitSetIsSet(keyState, BTN_Y) +
		    OFBitSetIsSet(keyState, BTN_C),
		    -OFBitSetIsSet(keyState, BTN_SELECT) +
		    OFBitSetIsSet(keyState, BTN_X));
	else if (_hasRightAnalogStick) {
		struct input_absinfo infoX, infoY;

		if (ioctl(_fd, EVIOCGABS(_rightAnalogStickXBit), &infoX) == -1)
			@throw [OFReadFailedException
			    exceptionWithObject: self
				requestedLength: sizeof(infoX)
					  errNo: errno];

		if (ioctl(_fd, EVIOCGABS(_rightAnalogStickYBit), &infoY) == -1)
			@throw [OFReadFailedException
			    exceptionWithObject: self
				requestedLength: sizeof(infoY)
					  errNo: errno];

		_rightAnalogStickMinX = infoX.minimum;
		_rightAnalogStickMaxX = infoX.maximum;
		_rightAnalogStickMinY = infoY.minimum;
		_rightAnalogStickMaxY = infoY.maximum;
		_rightAnalogStickPosition.x = scale(infoX.value,
		    _rightAnalogStickMinX, _rightAnalogStickMaxX);
		_rightAnalogStickPosition.y = scale(infoY.value,
		    _rightAnalogStickMinY, _rightAnalogStickMaxY);
	}

	if (_hasLeftTriggerPressure) {
		struct input_absinfo info;

		if (ioctl(_fd, EVIOCGABS( _leftTriggerPressureBit), &info) ==
		    -1)
			@throw [OFReadFailedException
			    exceptionWithObject: self
				requestedLength: sizeof(info)
					  errNo: errno];

		_leftTriggerMinPressure = info.minimum;
		_leftTriggerMaxPressure = info.maximum;
		_leftTriggerPressure = scale(info.value,
		    _leftTriggerMinPressure,
		    _leftTriggerMaxPressure);
	}

	if (_hasRightTriggerPressure) {
		struct input_absinfo info;

		if (ioctl(_fd, EVIOCGABS(_rightTriggerPressureBit), &info) ==
		    -1)
			@throw [OFReadFailedException
			    exceptionWithObject: self
				requestedLength: sizeof(info)
					  errNo: errno];

		_rightTriggerMinPressure = info.minimum;
		_rightTriggerMaxPressure = info.maximum;
		_leftTriggerPressure = scale(info.value,
		    _leftTriggerMinPressure,
		    _leftTriggerMaxPressure);
	}
}

- (void)retrieveState
{
	struct input_event event;

	for (;;) {
		OFGameControllerButton button;

		errno = 0;

		if (read(_fd, &event, sizeof(event)) < (int)sizeof(event)) {
			if (errno == EWOULDBLOCK)
				return;

			@throw [OFReadFailedException
			    exceptionWithObject: self
				requestedLength: sizeof(event)
					  errNo: errno];
		}

		if (_discardUntilReport) {
			if (event.type == EV_SYN && event.value == SYN_REPORT) {
				_discardUntilReport = false;
				[self of_pollState];
			}

			continue;
		}

		switch (event.type) {
		case EV_SYN:
			if (event.value == SYN_DROPPED) {
				_discardUntilReport = true;
				continue;
			}
			break;
		case EV_KEY:
			if ((button = buttonToName(event.code, _vendorID,
			    _productID)) != nil) {
				if (event.value)
					[_pressedButtons addObject: button];
				else
					[_pressedButtons removeObject: button];