backport commit 0b3496f:
Add support for SDL3 joystick input driver

Index: platform/x11/joypad_linux.cpp
--- platform/x11/joypad_linux.cpp.orig
+++ platform/x11/joypad_linux.cpp
@@ -1,595 +1 @@
-/**************************************************************************/
-/*  joypad_linux.cpp                                                      */
-/**************************************************************************/
-/*                         This file is part of:                          */
-/*                             GODOT ENGINE                               */
-/*                        https://godotengine.org                         */
-/**************************************************************************/
-/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
-/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
-/*                                                                        */
-/* Permission is hereby granted, free of charge, to any person obtaining  */
-/* a copy of this software and associated documentation files (the        */
-/* "Software"), to deal in the Software without restriction, including    */
-/* without limitation the rights to use, copy, modify, merge, publish,    */
-/* distribute, sublicense, and/or sell copies of the Software, and to     */
-/* permit persons to whom the Software is furnished to do so, subject to  */
-/* the following conditions:                                              */
-/*                                                                        */
-/* The above copyright notice and this permission notice shall be         */
-/* included in all copies or substantial portions of the Software.        */
-/*                                                                        */
-/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
-/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
-/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
-/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
-/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
-/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
-/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
-/**************************************************************************/
 
-#ifdef JOYDEV_ENABLED
-
-#include "joypad_linux.h"
-
-#include "core/os/os.h"
-
-#include <dirent.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <linux/input.h>
-#include <unistd.h>
-
-#ifdef UDEV_ENABLED
-#include "libudev-so_wrap.h"
-#endif
-
-#define LONG_BITS (sizeof(long) * 8)
-#define test_bit(nr, addr) (((1UL << ((nr) % LONG_BITS)) & ((addr)[(nr) / LONG_BITS])) != 0)
-#define NBITS(x) ((((x)-1) / LONG_BITS) + 1)
-
-#ifdef UDEV_ENABLED
-static const char *ignore_str = "/dev/input/js";
-#endif
-
-JoypadLinux::Joypad::Joypad() {
-	fd = -1;
-	dpad = 0;
-	devpath = "";
-	for (int i = 0; i < MAX_ABS; i++) {
-		abs_info[i] = nullptr;
-	}
-}
-
-JoypadLinux::Joypad::~Joypad() {
-	for (int i = 0; i < MAX_ABS; i++) {
-		if (abs_info[i]) {
-			memdelete(abs_info[i]);
-		}
-	}
-}
-
-void JoypadLinux::Joypad::reset() {
-	dpad = 0;
-	fd = -1;
-	for (int i = 0; i < MAX_ABS; i++) {
-		abs_map[i] = -1;
-		curr_axis[i] = 0;
-	}
-	events.clear();
-}
-
-#ifdef UDEV_ENABLED
-// This function is derived from SDL:
-// https://github.com/libsdl-org/SDL/blob/main/src/core/linux/SDL_sandbox.c#L28-L45
-static bool detect_sandbox() {
-	if (access("/.flatpak-info", F_OK) == 0) {
-		return true;
-	}
-
-	// For Snap, we check multiple variables because they might be set for
-	// unrelated reasons. This is the same thing WebKitGTK does.
-	if (OS::get_singleton()->has_environment("SNAP") && OS::get_singleton()->has_environment("SNAP_NAME") && OS::get_singleton()->has_environment("SNAP_REVISION")) {
-		return true;
-	}
-
-	if (access("/run/host/container-manager", F_OK) == 0) {
-		return true;
-	}
-
-	return false;
-}
-#endif // UDEV_ENABLED
-
-JoypadLinux::JoypadLinux(InputDefault *in) {
-#ifdef UDEV_ENABLED
-	if (detect_sandbox()) {
-		// Linux binaries in sandboxes / containers need special handling because
-		// libudev doesn't work there. So we need to fallback to manual parsing
-		// of /dev/input in such case.
-		use_udev = false;
-		print_verbose("JoypadLinux: udev enabled, but detected incompatible sandboxed mode. Falling back to /dev/input to detect joypads.");
-	} else {
-		use_udev = initialize_libudev() == 0;
-		if (use_udev) {
-			print_verbose("JoypadLinux: udev enabled and loaded successfully.");
-		} else {
-			print_verbose("JoypadLinux: udev enabled, but couldn't be loaded. Falling back to /dev/input to detect joypads.");
-		}
-	}
-#else
-	print_verbose("JoypadLinux: udev disabled, parsing /dev/input to detect joypads.");
-#endif
-	input = in;
-	monitor_joypads_thread.start(monitor_joypads_thread_func, this);
-	joypad_events_thread.start(joypad_events_thread_func, this);
-}
-
-JoypadLinux::~JoypadLinux() {
-	monitor_joypads_exit.set();
-	joypad_events_exit.set();
-	monitor_joypads_thread.wait_to_finish();
-	joypad_events_thread.wait_to_finish();
-	close_joypads();
-}
-
-void JoypadLinux::monitor_joypads_thread_func(void *p_user) {
-	if (p_user) {
-		JoypadLinux *joy = (JoypadLinux *)p_user;
-		joy->monitor_joypads_thread_run();
-	}
-}
-
-void JoypadLinux::monitor_joypads_thread_run() {
-#ifdef UDEV_ENABLED
-	if (use_udev) {
-		udev *_udev = udev_new();
-		if (!_udev) {
-			use_udev = false;
-			ERR_PRINT("Failed getting an udev context, falling back to parsing /dev/input.");
-			monitor_joypads();
-		} else {
-			enumerate_joypads(_udev);
-			monitor_joypads(_udev);
-			udev_unref(_udev);
-		}
-	} else {
-		monitor_joypads();
-	}
-#else
-	monitor_joypads();
-#endif
-}
-
-#ifdef UDEV_ENABLED
-void JoypadLinux::enumerate_joypads(udev *p_udev) {
-	udev_enumerate *enumerate;
-	udev_list_entry *devices, *dev_list_entry;
-	udev_device *dev;
-
-	enumerate = udev_enumerate_new(p_udev);
-	udev_enumerate_add_match_subsystem(enumerate, "input");
-
-	udev_enumerate_scan_devices(enumerate);
-	devices = udev_enumerate_get_list_entry(enumerate);
-	udev_list_entry_foreach(dev_list_entry, devices) {
-		const char *path = udev_list_entry_get_name(dev_list_entry);
-		dev = udev_device_new_from_syspath(p_udev, path);
-		const char *devnode = udev_device_get_devnode(dev);
-
-		if (devnode) {
-			String devnode_str = devnode;
-			if (devnode_str.find(ignore_str) == -1) {
-				open_joypad(devnode);
-			}
-		}
-		udev_device_unref(dev);
-	}
-	udev_enumerate_unref(enumerate);
-}
-
-void JoypadLinux::monitor_joypads(udev *p_udev) {
-	udev_device *dev = nullptr;
-	udev_monitor *mon = udev_monitor_new_from_netlink(p_udev, "udev");
-	udev_monitor_filter_add_match_subsystem_devtype(mon, "input", nullptr);
-	udev_monitor_enable_receiving(mon);
-	int fd = udev_monitor_get_fd(mon);
-
-	while (!monitor_joypads_exit.is_set()) {
-		fd_set fds;
-		struct timeval tv;
-		int ret;
-
-		FD_ZERO(&fds);
-		FD_SET(fd, &fds);
-		tv.tv_sec = 0;
-		tv.tv_usec = 0;
-
-		ret = select(fd + 1, &fds, nullptr, nullptr, &tv);
-
-		/* Check if our file descriptor has received data. */
-		if (ret > 0 && FD_ISSET(fd, &fds)) {
-			/* Make the call to receive the device.
-			   select() ensured that this will not block. */
-			dev = udev_monitor_receive_device(mon);
-
-			if (dev && udev_device_get_devnode(dev) != nullptr) {
-				String action = udev_device_get_action(dev);
-				const char *devnode = udev_device_get_devnode(dev);
-				if (devnode) {
-					String devnode_str = devnode;
-					if (devnode_str.find(ignore_str) == -1) {
-						if (action == "add") {
-							open_joypad(devnode);
-						} else if (String(action) == "remove") {
-							close_joypad(devnode);
-						}
-					}
-				}
-				udev_device_unref(dev);
-			}
-		}
-		usleep(50000);
-	}
-	udev_monitor_unref(mon);
-}
-#endif
-
-void JoypadLinux::monitor_joypads() {
-	while (!monitor_joypads_exit.is_set()) {
-		DIR *input_directory;
-		input_directory = opendir("/dev/input");
-		if (input_directory) {
-			struct dirent *current;
-			char fname[64];
-
-			while ((current = readdir(input_directory)) != nullptr) {
-				if (strncmp(current->d_name, "event", 5) != 0) {
-					continue;
-				}
-				sprintf(fname, "/dev/input/%.*s", 16, current->d_name);
-				if (attached_devices.find(fname) == -1) {
-					open_joypad(fname);
-				}
-			}
-		}
-		closedir(input_directory);
-		usleep(1000000); // 1s
-	}
-}
-
-void JoypadLinux::close_joypads() {
-	for (int i = 0; i < JOYPADS_MAX; i++) {
-		MutexLock lock(joypads_mutex[i]);
-		Joypad &joypad = joypads[i];
-		close_joypad(joypad, i);
-	}
-}
-
-void JoypadLinux::close_joypad(const char *p_devpath) {
-	for (int i = 0; i < JOYPADS_MAX; i++) {
-		MutexLock lock(joypads_mutex[i]);
-		Joypad &joypad = joypads[i];
-		if (joypads[i].devpath == p_devpath) {
-			close_joypad(joypad, i);
-		}
-	}
-}
-
-void JoypadLinux::close_joypad(Joypad &p_joypad, int p_id) {
-	if (p_joypad.fd != -1) {
-		close(p_joypad.fd);
-		p_joypad.fd = -1;
-		attached_devices.erase(p_joypad.devpath);
-		input->joy_connection_changed(p_id, false, "");
-	};
-	p_joypad.events.clear();
-}
-
-static String _hex_str(uint8_t p_byte) {
-	static const char *dict = "0123456789abcdef";
-	char ret[3];
-	ret[2] = 0;
-
-	ret[0] = dict[p_byte >> 4];
-	ret[1] = dict[p_byte & 0xF];
-
-	return ret;
-}
-
-void JoypadLinux::setup_joypad_properties(Joypad &p_joypad) {
-	unsigned long keybit[NBITS(KEY_MAX)] = { 0 };
-	unsigned long absbit[NBITS(ABS_MAX)] = { 0 };
-
-	int num_buttons = 0;
-	int num_axes = 0;
-
-	if ((ioctl(p_joypad.fd, EVIOCGBIT(EV_KEY, sizeof(keybit)), keybit) < 0) ||
-			(ioctl(p_joypad.fd, EVIOCGBIT(EV_ABS, sizeof(absbit)), absbit) < 0)) {
-		return;
-	}
-	for (int i = BTN_JOYSTICK; i < KEY_MAX; ++i) {
-		if (test_bit(i, keybit)) {
-			p_joypad.key_map[i] = num_buttons++;
-		}
-	}
-	for (int i = BTN_MISC; i < BTN_JOYSTICK; ++i) {
-		if (test_bit(i, keybit)) {
-			p_joypad.key_map[i] = num_buttons++;
-		}
-	}
-	for (int i = 0; i < ABS_MISC; ++i) {
-		/* Skip hats */
-		if (i == ABS_HAT0X) {
-			i = ABS_HAT3Y;
-			continue;
-		}
-		if (test_bit(i, absbit)) {
-			p_joypad.abs_map[i] = num_axes++;
-			p_joypad.abs_info[i] = memnew(input_absinfo);
-			if (ioctl(p_joypad.fd, EVIOCGABS(i), p_joypad.abs_info[i]) < 0) {
-				memdelete(p_joypad.abs_info[i]);
-				p_joypad.abs_info[i] = nullptr;
-			}
-		}
-	}
-
-	p_joypad.force_feedback = false;
-	p_joypad.ff_effect_timestamp = 0;
-	unsigned long ffbit[NBITS(FF_CNT)];
-	if (ioctl(p_joypad.fd, EVIOCGBIT(EV_FF, sizeof(ffbit)), ffbit) != -1) {
-		if (test_bit(FF_RUMBLE, ffbit)) {
-			p_joypad.force_feedback = true;
-		}
-	}
-}
-
-void JoypadLinux::open_joypad(const char *p_path) {
-	int joy_num = input->get_unused_joy_id();
-	int fd = open(p_path, O_RDWR | O_NONBLOCK);
-	if (fd != -1 && joy_num != -1) {
-		unsigned long evbit[NBITS(EV_MAX)] = { 0 };
-		unsigned long keybit[NBITS(KEY_MAX)] = { 0 };
-		unsigned long absbit[NBITS(ABS_MAX)] = { 0 };
-
-		// add to attached devices so we don't try to open it again
-		attached_devices.push_back(String(p_path));
-
-		if ((ioctl(fd, EVIOCGBIT(0, sizeof(evbit)), evbit) < 0) ||
-				(ioctl(fd, EVIOCGBIT(EV_KEY, sizeof(keybit)), keybit) < 0) ||
-				(ioctl(fd, EVIOCGBIT(EV_ABS, sizeof(absbit)), absbit) < 0)) {
-			close(fd);
-			return;
-		}
-
-		//check if the device supports basic gamepad events, prevents certain keyboards from
-		//being detected as joypads
-		if (!(test_bit(EV_KEY, evbit) && test_bit(EV_ABS, evbit) &&
-					(test_bit(ABS_X, absbit) || test_bit(ABS_Y, absbit) || test_bit(ABS_HAT0X, absbit) ||
-							test_bit(ABS_GAS, absbit) || test_bit(ABS_RUDDER, absbit)) &&
-					(test_bit(BTN_A, keybit) || test_bit(BTN_THUMBL, keybit) ||
-							test_bit(BTN_TRIGGER, keybit) || test_bit(BTN_1, keybit))) &&
-				!(test_bit(EV_ABS, evbit) &&
-						test_bit(ABS_X, absbit) && test_bit(ABS_Y, absbit) &&
-						test_bit(ABS_RX, absbit) && test_bit(ABS_RY, absbit))) {
-			close(fd);
-			return;
-		}
-
-		char uid[128];
-		char namebuf[128];
-		String name = "";
-		input_id inpid;
-		if (ioctl(fd, EVIOCGNAME(sizeof(namebuf)), namebuf) >= 0) {
-			name = namebuf;
-		}
-
-		if (ioctl(fd, EVIOCGID, &inpid) < 0) {
-			close(fd);
-			return;
-		}
-
-		uint16_t vendor = BSWAP16(inpid.vendor);
-		uint16_t product = BSWAP16(inpid.product);
-		uint16_t version = BSWAP16(inpid.version);
-
-		if (input->should_ignore_device(vendor, product)) {
-			// This can be true in cases where Steam is passing information into the game to ignore
-			// original gamepads when using virtual rebindings (See SteamInput).
-			return;
-		}
-
-		MutexLock lock(joypads_mutex[joy_num]);
-		Joypad &joypad = joypads[joy_num];
-		joypad.reset();
-		joypad.fd = fd;
-		joypad.devpath = String(p_path);
-		setup_joypad_properties(joypad);
-		sprintf(uid, "%04x%04x", BSWAP16(inpid.bustype), 0);
-		if (inpid.vendor && inpid.product && inpid.version) {
-			sprintf(uid + String(uid).length(), "%04x%04x%04x%04x%04x%04x", vendor, 0, product, 0, version, 0);
-			input->joy_connection_changed(joy_num, true, name, uid);
-		} else {
-			String uidname = uid;
-			int uidlen = MIN(name.length(), 11);
-			for (int i = 0; i < uidlen; i++) {
-				uidname = uidname + _hex_str(name[i]);
-			}
-			uidname += "00";
-			input->joy_connection_changed(joy_num, true, name, uidname);
-		}
-	}
-}
-
-void JoypadLinux::joypad_vibration_start(Joypad &p_joypad, float p_weak_magnitude, float p_strong_magnitude, float p_duration, uint64_t p_timestamp) {
-	if (!p_joypad.force_feedback || p_joypad.fd == -1 || p_weak_magnitude < 0.f || p_weak_magnitude > 1.f || p_strong_magnitude < 0.f || p_strong_magnitude > 1.f) {
-		return;
-	}
-	if (p_joypad.ff_effect_id != -1) {
-		joypad_vibration_stop(p_joypad, p_timestamp);
-	}
-
-	struct ff_effect effect;
-	effect.type = FF_RUMBLE;
-	effect.id = -1;
-	effect.u.rumble.weak_magnitude = floor(p_weak_magnitude * (float)0xffff);
-	effect.u.rumble.strong_magnitude = floor(p_strong_magnitude * (float)0xffff);
-	effect.replay.length = floor(p_duration * 1000);
-	effect.replay.delay = 0;
-
-	if (ioctl(p_joypad.fd, EVIOCSFF, &effect) < 0) {
-		return;
-	}
-
-	struct input_event play;
-	play.type = EV_FF;
-	play.code = effect.id;
-	play.value = 1;
-	if (write(p_joypad.fd, (const void *)&play, sizeof(play)) == -1) {
-		print_verbose("Couldn't write to Joypad device.");
-	}
-
-	p_joypad.ff_effect_id = effect.id;
-	p_joypad.ff_effect_timestamp = p_timestamp;
-}
-
-void JoypadLinux::joypad_vibration_stop(Joypad &p_joypad, uint64_t p_timestamp) {
-	if (!p_joypad.force_feedback || p_joypad.fd == -1 || p_joypad.ff_effect_id == -1) {
-		return;
-	}
-
-	if (ioctl(p_joypad.fd, EVIOCRMFF, p_joypad.ff_effect_id) < 0) {
-		return;
-	}
-
-	p_joypad.ff_effect_id = -1;
-	p_joypad.ff_effect_timestamp = p_timestamp;
-}
-
-float JoypadLinux::axis_correct(const input_absinfo *p_abs, int p_value) const {
-	int min = p_abs->minimum;
-	int max = p_abs->maximum;
-	// Convert to a value between -1.0f and 1.0f.
-	return 2.0f * (p_value - min) / (max - min) - 1.0f;
-}
-
-void JoypadLinux::joypad_events_thread_func(void *p_user) {
-	if (p_user) {
-		JoypadLinux *joy = (JoypadLinux *)p_user;
-		joy->joypad_events_thread_run();
-	}
-}
-
-void JoypadLinux::joypad_events_thread_run() {
-	while (!joypad_events_exit.is_set()) {
-		bool no_events = true;
-		for (int i = 0; i < JOYPADS_MAX; i++) {
-			MutexLock lock(joypads_mutex[i]);
-			Joypad &joypad = joypads[i];
-			if (joypad.fd == -1) {
-				continue;
-			}
-			input_event event;
-			while (read(joypad.fd, &event, sizeof(event)) > 0) {
-				JoypadEvent joypad_event;
-				joypad_event.type = event.type;
-				joypad_event.code = event.code;
-				joypad_event.value = event.value;
-				joypad.events.push_back(joypad_event);
-			}
-			if (errno != EAGAIN) {
-				close_joypad(joypad, i);
-			}
-		}
-		if (no_events) {
-			usleep(10000); // 10ms
-		}
-	}
-}
-
-void JoypadLinux::process_joypads() {
-	for (int i = 0; i < JOYPADS_MAX; i++) {
-		MutexLock lock(joypads_mutex[i]);
-		Joypad &joypad = joypads[i];
-		if (joypad.fd == -1) {
-			continue;
-		}
-		for (uint32_t j = 0; j < joypad.events.size(); j++) {
-			const JoypadEvent &joypad_event = joypad.events[j];
-			// joypad_event may be tainted and out of MAX_KEY range, which will cause
-			// joypad.key_map[joypad_event.code] to crash
-			if (joypad_event.code >= MAX_KEY) {
-				return;
-			}
-
-			switch (joypad_event.type) {
-				case EV_KEY:
-					input->joy_button(i, joypad.key_map[joypad_event.code], joypad_event.value);
-					break;
-
-				case EV_ABS:
-					switch (joypad_event.code) {
-						case ABS_HAT0X:
-							if (joypad_event.value != 0) {
-								if (joypad_event.value < 0) {
-									joypad.dpad = (joypad.dpad | InputDefault::HAT_MASK_LEFT) & ~InputDefault::HAT_MASK_RIGHT;
-								} else {
-									joypad.dpad = (joypad.dpad | InputDefault::HAT_MASK_RIGHT) & ~InputDefault::HAT_MASK_LEFT;
-								}
-							} else {
-								joypad.dpad &= ~(InputDefault::HAT_MASK_LEFT | InputDefault::HAT_MASK_RIGHT);
-							}
-							input->joy_hat(i, joypad.dpad);
-							break;
-
-						case ABS_HAT0Y:
-							if (joypad_event.value != 0) {
-								if (joypad_event.value < 0) {
-									joypad.dpad = (joypad.dpad | InputDefault::HAT_MASK_UP) & ~InputDefault::HAT_MASK_DOWN;
-								} else {
-									joypad.dpad = (joypad.dpad | InputDefault::HAT_MASK_DOWN) & ~InputDefault::HAT_MASK_UP;
-								}
-							} else {
-								joypad.dpad &= ~(InputDefault::HAT_MASK_UP | InputDefault::HAT_MASK_DOWN);
-							}
-							input->joy_hat(i, joypad.dpad);
-							break;
-
-						default:
-							if (joypad_event.code >= MAX_ABS) {
-								return;
-							}
-							if (joypad.abs_map[joypad_event.code] != -1 && joypad.abs_info[joypad_event.code]) {
-								float value = axis_correct(joypad.abs_info[joypad_event.code], joypad_event.value);
-								joypad.curr_axis[joypad.abs_map[joypad_event.code]] = value;
-							}
-							break;
-					}
-					break;
-			}
-		}
-		joypad.events.clear();
-
-		for (int j = 0; j < MAX_ABS; j++) {
-			int index = joypad.abs_map[j];
-			if (index != -1) {
-				input->joy_axis(i, index, joypad.curr_axis[index]);
-			}
-		}
-
-		if (joypad.force_feedback) {
-			uint64_t timestamp = input->get_joy_vibration_timestamp(i);
-			if (timestamp > joypad.ff_effect_timestamp) {
-				Vector2 strength = input->get_joy_vibration_strength(i);
-				float duration = input->get_joy_vibration_duration(i);
-				if (strength.x == 0 && strength.y == 0) {
-					joypad_vibration_stop(joypad, timestamp);
-				} else {
-					joypad_vibration_start(joypad, strength.x, strength.y, duration, timestamp);
-				}
-			}
-		}
-	}
-}
-
-#endif // JOYDEV_ENABLED
