SDL_sysjoystick.c
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2019 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_error.h"
#include "SDL_events.h"
#include "SDL_joystick.h"
#include "SDL_assert.h"
#include "SDL_timer.h"
#include "SDL_log.h"
#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 int instance_counter = 0;
static EM_BOOL
Emscripten_JoyStickConnected(int eventType, const EmscriptenGamepadEvent *gamepadEvent, void *userData)
{
int i;
SDL_joylist_item *item;
if (JoystickByIndex(gamepadEvent->index) != NULL) {
return 1;
}
item = (SDL_joylist_item *) SDL_malloc(sizeof (SDL_joylist_item));
if (item == NULL) {
return 1;
}
SDL_zerop(item);
item->index = gamepadEvent->index;
item->name = SDL_strdup(gamepadEvent->id);
if ( item->name == NULL ) {
SDL_free(item);
return 1;
}
item->mapping = SDL_strdup(gamepadEvent->mapping);
if ( item->mapping == NULL ) {
SDL_free(item->name);
SDL_free(item);
return 1;
}
item->naxes = gamepadEvent->numAxes;
item->nbuttons = gamepadEvent->numButtons;
item->device_instance = instance_counter++;
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 == NULL) {
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
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;
while (item != NULL) {
if (item->index == gamepadEvent->index) {
break;
}
prev = item;
item = item->next;
}
if (item == NULL) {
return 1;
}
if (item->joystick) {
item->joystick->hwdata = NULL;
}
if (prev != NULL) {
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);
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;
instance_counter = 0;
emscripten_set_gamepadconnected_callback(NULL, 0, NULL);
emscripten_set_gamepaddisconnected_callback(NULL, 0, NULL);
}
/* Function to scan the system for joysticks.
* It should return 0, or -1 on an unrecoverable fatal error.
*/
static int
EMSCRIPTEN_JoystickInit(void)
{
int retval, i, numjs;
EmscriptenGamepadEvent gamepadState;
numjoysticks = 0;
retval = emscripten_sample_gamepad_data();
/* Check if gamepad is supported by browser */
if (retval == 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++) {
retval = emscripten_get_gamepad_status(i, &gamepadState);
if (retval == EMSCRIPTEN_RESULT_SUCCESS) {
Emscripten_JoyStickConnected(EMSCRIPTEN_EVENT_GAMEPADCONNECTED,
&gamepadState,
NULL);
}
}
}
retval = emscripten_set_gamepadconnected_callback(NULL,
0,
Emscripten_JoyStickConnected);
if(retval != EMSCRIPTEN_RESULT_SUCCESS) {
EMSCRIPTEN_JoystickQuit();
return SDL_SetError("Could not set gamepad connect callback");
}
retval = emscripten_set_gamepaddisconnected_callback(NULL,
0,
Emscripten_JoyStickDisconnected);
if(retval != EMSCRIPTEN_RESULT_SUCCESS) {
EMSCRIPTEN_JoystickQuit();
return SDL_SetError("Could not set gamepad disconnect callback");
}
return 0;
}
/* 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 != NULL) {
if (item->index == index) {
break;
}
item = item->next;
}
return item;
}
static int
EMSCRIPTEN_JoystickGetCount(void)
{
return numjoysticks;
}
static void
EMSCRIPTEN_JoystickDetect(void)
{
}
static const char *
EMSCRIPTEN_JoystickGetDeviceName(int device_index)
{
return JoystickByDeviceIndex(device_index)->name;
}
static int
EMSCRIPTEN_JoystickGetDevicePlayerIndex(int device_index)
{
return -1;
}
static SDL_JoystickID
EMSCRIPTEN_JoystickGetDeviceInstanceID(int device_index)
{
return JoystickByDeviceIndex(device_index)->device_instance;
}
/* Function to open a joystick for use.
The joystick to open is specified by the device index.
This should fill the nbuttons and naxes fields of the joystick structure.
It returns 0, or -1 if there is an error.
*/
static int
EMSCRIPTEN_JoystickOpen(SDL_Joystick * joystick, int device_index)
{
SDL_joylist_item *item = JoystickByDeviceIndex(device_index);
if (item == NULL ) {
return SDL_SetError("No such device");
}
if (item->joystick != NULL) {
return SDL_SetError("Joystick already opened");
}
joystick->instance_id = item->device_instance;
joystick->hwdata = (struct joystick_hwdata *) item;
item->joystick = joystick;
/* HTML5 Gamepad API doesn't say anything about these */
joystick->nhats = 0;
joystick->nballs = 0;
joystick->nbuttons = item->nbuttons;
joystick->naxes = item->naxes;
return (0);
}
/* 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, buttonState;
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]) {
buttonState = gamepadState.digitalButton[i]? SDL_PRESSED: SDL_RELEASED;
SDL_PrivateJoystickButton(item->joystick, i, buttonState);
}
/* 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_PrivateJoystickAxis(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_JoystickGUID
EMSCRIPTEN_JoystickGetDeviceGUID(int device_index)
{
SDL_JoystickGUID guid;
/* the GUID is just the first 16 chars of the name for now */
const char *name = EMSCRIPTEN_JoystickGetDeviceName(device_index);
SDL_zero(guid);
SDL_memcpy(&guid, name, SDL_min(sizeof(guid), SDL_strlen(name)));
return guid;
}
static int
EMSCRIPTEN_JoystickRumble(SDL_Joystick * joystick, Uint16 low_frequency_rumble, Uint16 high_frequency_rumble, Uint32 duration_ms)
{
return SDL_Unsupported();
}
SDL_JoystickDriver SDL_EMSCRIPTEN_JoystickDriver =
{
EMSCRIPTEN_JoystickInit,
EMSCRIPTEN_JoystickGetCount,
EMSCRIPTEN_JoystickDetect,
EMSCRIPTEN_JoystickGetDeviceName,
EMSCRIPTEN_JoystickGetDevicePlayerIndex,
EMSCRIPTEN_JoystickGetDeviceGUID,
EMSCRIPTEN_JoystickGetDeviceInstanceID,
EMSCRIPTEN_JoystickOpen,
EMSCRIPTEN_JoystickRumble,
EMSCRIPTEN_JoystickUpdate,
EMSCRIPTEN_JoystickClose,
EMSCRIPTEN_JoystickQuit,
};
#endif /* SDL_JOYSTICK_EMSCRIPTEN */
/* vi: set ts=4 sw=4 expandtab: */
SDL_zero
#define SDL_zero(x)
Definition: SDL_stdinc.h:416
Uint32
uint32_t Uint32
Definition: SDL_stdinc.h:203
SDL_events.h
joystick_hwdata::guid
SDL_JoystickGUID guid
Definition: SDL_sysjoystick_c.h:71
numjoysticks
static int numjoysticks
Definition: SDL_sysjoystick.m:83
NULL
#define NULL
Definition: begin_code.h:167
SDL_timer.h
SDL_joystick.h
SDL_error.h
SDL_zerop
#define SDL_zerop(x)
Definition: SDL_stdinc.h:417
SDL_log.h
SDL_PrivateJoystickAdded
void SDL_PrivateJoystickAdded(SDL_JoystickID device_instance)
Definition: SDL_joystick.c:755
joystick_hwdata::joystick
SDL_Joystick * joystick
Definition: SDL_sysjoystick_c.h:42
index
GLuint index
Definition: SDL_opengl_glext.h:660
SDL_RELEASED
#define SDL_RELEASED
Definition: SDL_events.h:49
result
GLuint64EXT * result
Definition: SDL_opengl_glext.h:9432
SDL_PrivateJoystickRemoved
void SDL_PrivateJoystickRemoved(SDL_JoystickID device_instance)
Definition: SDL_joystick.c:805
SDL_PrivateJoystickAxis
int SDL_PrivateJoystickAxis(SDL_Joystick *joystick, Uint8 axis, Sint16 value)
Definition: SDL_joystick.c:833
SDL_JoystickID
Sint32 SDL_JoystickID
Definition: SDL_joystick.h:81
SDL_PRESSED
#define SDL_PRESSED
Definition: SDL_events.h:50
Sint16
int16_t Sint16
Definition: SDL_stdinc.h:185
SDL_memcpy
#define SDL_memcpy
Definition: SDL_dynapi_overrides.h:387
retval
SDL_bool retval
Definition: testgamecontroller.c:65
SDL_Log
#define SDL_Log
Definition: SDL_dynapi_overrides.h:31
SDL_free
#define SDL_free
Definition: SDL_dynapi_overrides.h:377
name
GLuint const GLchar * name
Definition: SDL_opengl_glext.h:660
SDL_PrivateJoystickButton
int SDL_PrivateJoystickButton(SDL_Joystick *joystick, Uint8 button, Uint8 state)
Definition: SDL_joystick.c:966
Uint16
uint16_t Uint16
Definition: SDL_stdinc.h:191
SDL_assert.h
SDL_min
#define SDL_min(x, y)
Definition: SDL_stdinc.h:406
SDL_assert
#define SDL_assert(condition)
Definition: SDL_assert.h:169
SDL_SetError
#define SDL_SetError
Definition: SDL_dynapi_overrides.h:30
joystick_hwdata::item
struct SDL_joylist_item * item
Definition: SDL_sysjoystick_c.h:33
SDL_strdup
#define SDL_strdup
Definition: SDL_dynapi_overrides.h:397
SDL_strlen
#define SDL_strlen
Definition: SDL_dynapi_overrides.h:393
SDL_Unsupported
#define SDL_Unsupported()
Definition: SDL_error.h:53
SDL_malloc
#define SDL_malloc
Definition: SDL_dynapi_overrides.h:374
SDL_JoystickGUID
Definition: SDL_joystick.h:70
SDL_EMSCRIPTEN_JoystickDriver
SDL_JoystickDriver SDL_EMSCRIPTEN_JoystickDriver
i
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50
joystick_hwdata
Definition: SDL_sysjoystick_c.h:46