src/sensor/SDL_syssensor.h

/*
  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"

#ifndef SDL_syssensor_c_h_
#define SDL_syssensor_c_h_

// This is the system specific header for the SDL sensor API

#include "SDL_sensor_c.h"

#define _guarded SDL_GUARDED_BY(SDL_sensor_lock)

// The SDL sensor structure
struct SDL_Sensor
{
    SDL_SensorID instance_id _guarded;   // Device instance, monotonically increasing from 0
    char *name _guarded;                 // Sensor name - system dependent
    SDL_SensorType type _guarded;        // Type of the sensor
    int non_portable_type _guarded;      // Platform dependent type of the sensor

    float data[16] _guarded;             // The current state of the sensor

    struct SDL_SensorDriver *driver _guarded;

    struct sensor_hwdata *hwdata _guarded; // Driver dependent information

    SDL_PropertiesID props _guarded;

    int ref_count _guarded; // Reference count for multiple opens

    struct SDL_Sensor *next _guarded; // pointer to next sensor we have allocated
};

#undef _guarded

typedef struct SDL_SensorDriver
{
    /* Function to scan the system for sensors.
     * sensor 0 should be the system default sensor.
     * This function should return 0, or -1 on an unrecoverable fatal error.
     */
    bool (*Init)(void);

    // Function to return the number of sensors available right now
    int (*GetCount)(void);

    // Function to check to see if the available sensors have changed
    void (*Detect)(void);

    // Function to get the device-dependent name of a sensor
    const char *(*GetDeviceName)(int device_index);

    // Function to get the type of a sensor
    SDL_SensorType (*GetDeviceType)(int device_index);

    // Function to get the platform dependent type of a sensor
    int (*GetDeviceNonPortableType)(int device_index);

    // Function to get the current instance id of the sensor located at device_index
    SDL_SensorID (*GetDeviceInstanceID)(int device_index);

    /* Function to open a sensor for use.
       The sensor to open is specified by the device index.
       It returns 0, or -1 if there is an error.
     */
    bool (*Open)(SDL_Sensor *sensor, int device_index);

    /* Function to update the state of a sensor - called as a device poll.
     * This function shouldn't update the sensor structure directly,
     * but instead should call SDL_SendSensorUpdate() to deliver events
     * and update sensor device state.
     */
    void (*Update)(SDL_Sensor *sensor);

    // Function to close a sensor after use
    void (*Close)(SDL_Sensor *sensor);

    // Function to perform any system-specific sensor related cleanup
    void (*Quit)(void);

} SDL_SensorDriver;

// The available sensor drivers
extern SDL_SensorDriver SDL_ANDROID_SensorDriver;
extern SDL_SensorDriver SDL_COREMOTION_SensorDriver;
extern SDL_SensorDriver SDL_WINDOWS_SensorDriver;
extern SDL_SensorDriver SDL_DUMMY_SensorDriver;
extern SDL_SensorDriver SDL_VITA_SensorDriver;
extern SDL_SensorDriver SDL_N3DS_SensorDriver;

#endif // SDL_syssensor_h_