1 files changed, 445 insertions, 0 deletions

diff --git a/contrib/SDL-3.2.8/src/joystick/emscripten/SDL_sysjoystick.c b/contrib/SDL-3.2.8/src/joystick/emscripten/SDL_sysjoystick.c
new file mode 100644
index 0000000..b481d5d
--- /dev/null
+++ b/contrib/SDL-3.2.8/src/joystick/emscripten/SDL_sysjoystick.c
@@ -0,0 +1,445 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "SDL_internal.h"
+
+#ifdef SDL_JOYSTICK_EMSCRIPTEN
+
+#include <stdio.h> // For the definition of NULL
+
+#include "SDL_sysjoystick_c.h"
+#include "../SDL_joystick_c.h"
+
+static SDL_joylist_item *JoystickByIndex(int index);
+
+static SDL_joylist_item *SDL_joylist = NULL;
+static SDL_joylist_item *SDL_joylist_tail = NULL;
+static int numjoysticks = 0;
+
+static EM_BOOL Emscripten_JoyStickConnected(int eventType, const EmscriptenGamepadEvent *gamepadEvent, void *userData)
+{
+    SDL_joylist_item *item;
+    int i;
+
+    SDL_LockJoysticks();
+
+    if (JoystickByIndex(gamepadEvent->index) != NULL) {
+        goto done;
+    }
+
+    item = (SDL_joylist_item *)SDL_malloc(sizeof(SDL_joylist_item));
+    if (!item) {
+        goto done;
+    }
+
+    SDL_zerop(item);
+    item->index = gamepadEvent->index;
+
+    item->name = SDL_CreateJoystickName(0, 0, NULL, gamepadEvent->id);
+    if (!item->name) {
+        SDL_free(item);
+        goto done;
+    }
+
+    item->mapping = SDL_strdup(gamepadEvent->mapping);
+    if (!item->mapping) {
+        SDL_free(item->name);
+        SDL_free(item);
+        goto done;
+    }
+
+    item->naxes = gamepadEvent->numAxes;
+    item->nbuttons = gamepadEvent->numButtons;
+    item->device_instance = SDL_GetNextObjectID();
+
+    item->timestamp = gamepadEvent->timestamp;
+
+    for (i = 0; i < item->naxes; i++) {
+        item->axis[i] = gamepadEvent->axis[i];
+    }
+
+    for (i = 0; i < item->nbuttons; i++) {
+        item->analogButton[i] = gamepadEvent->analogButton[i];
+        item->digitalButton[i] = gamepadEvent->digitalButton[i];
+    }
+
+    if (!SDL_joylist_tail) {
+        SDL_joylist = SDL_joylist_tail = item;
+    } else {
+        SDL_joylist_tail->next = item;
+        SDL_joylist_tail = item;
+    }
+
+    ++numjoysticks;
+
+    SDL_PrivateJoystickAdded(item->device_instance);
+
+#ifdef DEBUG_JOYSTICK
+    SDL_Log("Number of joysticks is %d", numjoysticks);
+#endif
+#ifdef DEBUG_JOYSTICK
+    SDL_Log("Added joystick with index %d", item->index);
+#endif
+
+done:
+    SDL_UnlockJoysticks();
+
+    return 1;
+}
+
+static EM_BOOL Emscripten_JoyStickDisconnected(int eventType, const EmscriptenGamepadEvent *gamepadEvent, void *userData)
+{
+    SDL_joylist_item *item = SDL_joylist;
+    SDL_joylist_item *prev = NULL;
+
+    SDL_LockJoysticks();
+
+    while (item) {
+        if (item->index == gamepadEvent->index) {
+            break;
+        }
+        prev = item;
+        item = item->next;
+    }
+
+    if (!item) {
+        goto done;
+    }
+
+    if (item->joystick) {
+        item->joystick->hwdata = NULL;
+    }
+
+    if (prev) {
+        prev->next = item->next;
+    } else {
+        SDL_assert(SDL_joylist == item);
+        SDL_joylist = item->next;
+    }
+    if (item == SDL_joylist_tail) {
+        SDL_joylist_tail = prev;
+    }
+
+    // Need to decrement the joystick count before we post the event
+    --numjoysticks;
+
+    SDL_PrivateJoystickRemoved(item->device_instance);
+
+#ifdef DEBUG_JOYSTICK
+    SDL_Log("Removed joystick with id %d", item->device_instance);
+#endif
+    SDL_free(item->name);
+    SDL_free(item->mapping);
+    SDL_free(item);
+
+done:
+    SDL_UnlockJoysticks();
+
+    return 1;
+}
+
+// Function to perform any system-specific joystick related cleanup
+static void EMSCRIPTEN_JoystickQuit(void)
+{
+    SDL_joylist_item *item = NULL;
+    SDL_joylist_item *next = NULL;
+
+    for (item = SDL_joylist; item; item = next) {
+        next = item->next;
+        SDL_free(item->mapping);
+        SDL_free(item->name);
+        SDL_free(item);
+    }
+
+    SDL_joylist = SDL_joylist_tail = NULL;
+
+    numjoysticks = 0;
+
+    emscripten_set_gamepadconnected_callback(NULL, 0, NULL);
+    emscripten_set_gamepaddisconnected_callback(NULL, 0, NULL);
+}
+
+// Function to scan the system for joysticks.
+static bool EMSCRIPTEN_JoystickInit(void)
+{
+    int rc, i, numjs;
+    EmscriptenGamepadEvent gamepadState;
+
+    numjoysticks = 0;
+
+    rc = emscripten_sample_gamepad_data();
+
+    // Check if gamepad is supported by browser
+    if (rc == EMSCRIPTEN_RESULT_NOT_SUPPORTED) {
+        return SDL_SetError("Gamepads not supported");
+    }
+
+    numjs = emscripten_get_num_gamepads();
+
+    // handle already connected gamepads
+    if (numjs > 0) {
+        for (i = 0; i < numjs; i++) {
+            rc = emscripten_get_gamepad_status(i, &gamepadState);
+            if (rc == EMSCRIPTEN_RESULT_SUCCESS) {
+                Emscripten_JoyStickConnected(EMSCRIPTEN_EVENT_GAMEPADCONNECTED,
+                                             &gamepadState,
+                                             NULL);
+            }
+        }
+    }
+
+    rc = emscripten_set_gamepadconnected_callback(NULL,
+                                                  0,
+                                                  Emscripten_JoyStickConnected);
+
+    if (rc != EMSCRIPTEN_RESULT_SUCCESS) {
+        EMSCRIPTEN_JoystickQuit();
+        return SDL_SetError("Could not set gamepad connect callback");
+    }
+
+    rc = emscripten_set_gamepaddisconnected_callback(NULL,
+                                                         0,
+                                                         Emscripten_JoyStickDisconnected);
+    if (rc != EMSCRIPTEN_RESULT_SUCCESS) {
+        EMSCRIPTEN_JoystickQuit();
+        return SDL_SetError("Could not set gamepad disconnect callback");
+    }
+
+    return true;
+}
+
+// Returns item matching given SDL device index.
+static SDL_joylist_item *JoystickByDeviceIndex(int device_index)
+{
+    SDL_joylist_item *item = SDL_joylist;
+
+    while (0 < device_index) {
+        --device_index;
+        item = item->next;
+    }
+
+    return item;
+}
+
+// Returns item matching given HTML gamepad index.
+static SDL_joylist_item *JoystickByIndex(int index)
+{
+    SDL_joylist_item *item = SDL_joylist;
+
+    if (index < 0) {
+        return NULL;
+    }
+
+    while (item) {
+        if (item->index == index) {
+            break;
+        }
+        item = item->next;
+    }
+
+    return item;
+}
+
+static int EMSCRIPTEN_JoystickGetCount(void)
+{
+    return numjoysticks;
+}
+
+static void EMSCRIPTEN_JoystickDetect(void)
+{
+}
+
+static bool EMSCRIPTEN_JoystickIsDevicePresent(Uint16 vendor_id, Uint16 product_id, Uint16 version, const char *name)
+{
+    // We don't override any other drivers
+    return false;
+}
+
+static const char *EMSCRIPTEN_JoystickGetDeviceName(int device_index)
+{
+    return JoystickByDeviceIndex(device_index)->name;
+}
+
+static const char *EMSCRIPTEN_JoystickGetDevicePath(int device_index)
+{
+    return NULL;
+}
+
+static int EMSCRIPTEN_JoystickGetDeviceSteamVirtualGamepadSlot(int device_index)
+{
+    return -1;
+}
+
+static int EMSCRIPTEN_JoystickGetDevicePlayerIndex(int device_index)
+{
+    return -1;
+}
+
+static void EMSCRIPTEN_JoystickSetDevicePlayerIndex(int device_index, int player_index)
+{
+}
+
+static SDL_JoystickID EMSCRIPTEN_JoystickGetDeviceInstanceID(int device_index)
+{
+    return JoystickByDeviceIndex(device_index)->device_instance;
+}
+
+static bool EMSCRIPTEN_JoystickOpen(SDL_Joystick *joystick, int device_index)
+{
+    SDL_joylist_item *item = JoystickByDeviceIndex(device_index);
+
+    if (!item) {
+        return SDL_SetError("No such device");
+    }
+
+    if (item->joystick) {
+        return SDL_SetError("Joystick already opened");
+    }
+
+    joystick->hwdata = (struct joystick_hwdata *)item;
+    item->joystick = joystick;
+
+    // HTML5 Gamepad API doesn't say anything about these
+    joystick->nhats = 0;
+
+    joystick->nbuttons = item->nbuttons;
+    joystick->naxes = item->naxes;
+
+    return true;
+}
+
+/* Function to update the state of a joystick - called as a device poll.
+ * This function shouldn't update the joystick structure directly,
+ * but instead should call SDL_PrivateJoystick*() to deliver events
+ * and update joystick device state.
+ */
+static void EMSCRIPTEN_JoystickUpdate(SDL_Joystick *joystick)
+{
+    EmscriptenGamepadEvent gamepadState;
+    SDL_joylist_item *item = (SDL_joylist_item *)joystick->hwdata;
+    int i, result;
+    Uint64 timestamp = SDL_GetTicksNS();
+
+    emscripten_sample_gamepad_data();
+
+    if (item) {
+        result = emscripten_get_gamepad_status(item->index, &gamepadState);
+        if (result == EMSCRIPTEN_RESULT_SUCCESS) {
+            if (gamepadState.timestamp == 0 || gamepadState.timestamp != item->timestamp) {
+                for (i = 0; i < item->nbuttons; i++) {
+                    if (item->digitalButton[i] != gamepadState.digitalButton[i]) {
+                        bool down = (gamepadState.digitalButton[i] != 0);
+                        SDL_SendJoystickButton(timestamp, item->joystick, i, down);
+                    }
+
+                    // store values to compare them in the next update
+                    item->analogButton[i] = gamepadState.analogButton[i];
+                    item->digitalButton[i] = gamepadState.digitalButton[i];
+                }
+
+                for (i = 0; i < item->naxes; i++) {
+                    if (item->axis[i] != gamepadState.axis[i]) {
+                        // do we need to do conversion?
+                        SDL_SendJoystickAxis(timestamp, item->joystick, i,
+                                                (Sint16)(32767. * gamepadState.axis[i]));
+                    }
+
+                    // store to compare in next update
+                    item->axis[i] = gamepadState.axis[i];
+                }
+
+                item->timestamp = gamepadState.timestamp;
+            }
+        }
+    }
+}
+
+// Function to close a joystick after use
+static void EMSCRIPTEN_JoystickClose(SDL_Joystick *joystick)
+{
+    SDL_joylist_item *item = (SDL_joylist_item *)joystick->hwdata;
+    if (item) {
+        item->joystick = NULL;
+    }
+}
+
+static SDL_GUID EMSCRIPTEN_JoystickGetDeviceGUID(int device_index)
+{
+    // the GUID is just the name for now
+    const char *name = EMSCRIPTEN_JoystickGetDeviceName(device_index);
+    return SDL_CreateJoystickGUIDForName(name);
+}
+
+static bool EMSCRIPTEN_JoystickRumble(SDL_Joystick *joystick, Uint16 low_frequency_rumble, Uint16 high_frequency_rumble)
+{
+    return SDL_Unsupported();
+}
+
+static bool EMSCRIPTEN_JoystickRumbleTriggers(SDL_Joystick *joystick, Uint16 left_rumble, Uint16 right_rumble)
+{
+    return SDL_Unsupported();
+}
+
+static bool EMSCRIPTEN_JoystickGetGamepadMapping(int device_index, SDL_GamepadMapping *out)
+{
+    return false;
+}
+
+static bool EMSCRIPTEN_JoystickSetLED(SDL_Joystick *joystick, Uint8 red, Uint8 green, Uint8 blue)
+{
+    return SDL_Unsupported();
+}
+
+static bool EMSCRIPTEN_JoystickSendEffect(SDL_Joystick *joystick, const void *data, int size)
+{
+    return SDL_Unsupported();
+}
+
+static bool EMSCRIPTEN_JoystickSetSensorsEnabled(SDL_Joystick *joystick, bool enabled)
+{
+    return SDL_Unsupported();
+}
+
+SDL_JoystickDriver SDL_EMSCRIPTEN_JoystickDriver = {
+    EMSCRIPTEN_JoystickInit,
+    EMSCRIPTEN_JoystickGetCount,
+    EMSCRIPTEN_JoystickDetect,
+    EMSCRIPTEN_JoystickIsDevicePresent,
+    EMSCRIPTEN_JoystickGetDeviceName,
+    EMSCRIPTEN_JoystickGetDevicePath,
+    EMSCRIPTEN_JoystickGetDeviceSteamVirtualGamepadSlot,
+    EMSCRIPTEN_JoystickGetDevicePlayerIndex,
+    EMSCRIPTEN_JoystickSetDevicePlayerIndex,
+    EMSCRIPTEN_JoystickGetDeviceGUID,
+    EMSCRIPTEN_JoystickGetDeviceInstanceID,
+    EMSCRIPTEN_JoystickOpen,
+    EMSCRIPTEN_JoystickRumble,
+    EMSCRIPTEN_JoystickRumbleTriggers,
+    EMSCRIPTEN_JoystickSetLED,
+    EMSCRIPTEN_JoystickSendEffect,
+    EMSCRIPTEN_JoystickSetSensorsEnabled,
+    EMSCRIPTEN_JoystickUpdate,
+    EMSCRIPTEN_JoystickClose,
+    EMSCRIPTEN_JoystickQuit,
+    EMSCRIPTEN_JoystickGetGamepadMapping
+};
+
+#endif // SDL_JOYSTICK_EMSCRIPTEN