/*

SDL - Simple DirectMedia Layer

This library is free software; you can redistribute it and/or

modify it under the terms of the GNU Library General Public

License as published by the Free Software Foundation; either

version 2 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

Library General Public License for more details.

You should have received a copy of the GNU Library General Public

License along with this library; if not, write to the Free

Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

Sam Lantinga

#ifdef SDL_JOYSTICK_IOKIT

/* Written 2001 by Max Horn */

#include <unistd.h>

#include <ctype.h>

#include <sysexits.h>

#include <mach/mach.h>

#include <mach/mach_error.h>

#include <IOKit/IOKitLib.h>

#include <IOKit/IOCFPlugIn.h>

#ifdef MACOS_10_0_4

#include <IOKit/hidsystem/IOHIDUsageTables.h>

#else

#if MAC_OS_X_VERSION_MIN_REQUIRED == 1030

#include "10.3.9-FIX/IOHIDLib.h"

#else

#include <IOKit/hid/IOHIDKeys.h>

#include <CoreFoundation/CoreFoundation.h>

#include "SDL_joystick.h"

#include "../SDL_sysjoystick.h"

#include "../SDL_joystick_c.h"

struct recElement

{

IOHIDElementCookie cookie; /* unique value which identifies element, will NOT change */

long min; /* reported min value possible */

long max; /* reported max value possible */

#if 0

/* TODO: maybe should handle the following stuff somehow? */

long scaledMin; /* reported scaled min value possible */

long scaledMax; /* reported scaled max value possible */

long size; /* size in bits of data return from element */

Boolean relative; /* are reports relative to last report (deltas) */

Boolean wrapping; /* does element wrap around (one value higher than max is min) */

Boolean nonLinear; /* are the values reported non-linear relative to element movement */

Boolean preferredState; /* does element have a preferred state (such as a button) */

Boolean nullState; /* does element have null state */

#endif /* 0 */

/* runtime variables used for auto-calibration */

long minReport; /* min returned value */

long maxReport; /* max returned value */

};

typedef struct recElement recElement;

struct joystick_hwdata

{

char product[256]; /* name of product */

long usage; /* usage page from IOUSBHID Parser.h which defines general usage */

long usagePage; /* usage within above page from IOUSBHID Parser.h which defines specific usage */

long axes; /* number of axis (calculated, not reported by device) */

long buttons; /* number of buttons (calculated, not reported by device) */

long hats; /* number of hat switches (calculated, not reported by device) */

long elements; /* number of total elements (shouldbe total of above) (calculated, not reported by device) */

recElement* firstAxis;

recElement* firstButton;

recElement* firstHat;

int removed;

int uncentered;

};

typedef struct joystick_hwdata recDevice;

/* Linked list of all available devices */

static recDevice *gpDeviceList = NULL;

{

SDL_SetError(strError);

}

static void HIDGetCollectionElements (CFMutableDictionaryRef deviceProperties, recDevice *pDevice);

/* returns current value for element, polling element

* will return 0 on error conditions which should be accounted for by application

*/

{

IOReturn result = kIOReturnSuccess;

IOHIDEventStruct hidEvent;

hidEvent.value = 0;

if (NULL != pDevice && NULL != pElement && NULL != pDevice->interface)

{

result = (*(pDevice->interface))->getElementValue(pDevice->interface, pElement->cookie, &hidEvent);

if (kIOReturnSuccess == result)

{

/* record min and max for auto calibration */

if (hidEvent.value < pElement->minReport)

pElement->minReport = hidEvent.value;

if (hidEvent.value > pElement->maxReport)

pElement->maxReport = hidEvent.value;

}

}

return hidEvent.value;

}

{

float deviceScale = max - min;

float readScale = pElement->maxReport - pElement->minReport;

SInt32 value = HIDGetElementValue(pDevice, pElement);

if (readScale == 0)

else

return ((value - pElement->minReport) * deviceScale / readScale) + min;

}

static void HIDRemovalCallback(void * target,

IOReturn result,

void * refcon,

void * sender)

{

recDevice *device = (recDevice *) refcon;

device->removed = 1;

device->uncentered = 1;

}

/* Create and open an interface to device, required prior to extracting values or building queues.

* Note: appliction now owns the device and must close and release it prior to exiting

*/

{

IOReturn result = kIOReturnSuccess;

HRESULT plugInResult = S_OK;

SInt32 score = 0;

IOCFPlugInInterface ** ppPlugInInterface = NULL;

if (NULL == pDevice->interface)

{

result = IOCreatePlugInInterfaceForService (hidDevice, kIOHIDDeviceUserClientTypeID,

kIOCFPlugInInterfaceID, &ppPlugInInterface, &score);

if (kIOReturnSuccess == result)

{

plugInResult = (*ppPlugInInterface)->QueryInterface (ppPlugInInterface,

CFUUIDGetUUIDBytes (kIOHIDDeviceInterfaceID), (void *) &(pDevice->interface));

if (S_OK != plugInResult)

HIDReportErrorNum ("CouldnÕt query HID class device interface from plugInInterface", plugInResult);

(*ppPlugInInterface)->Release (ppPlugInInterface);

}

else

HIDReportErrorNum ("Failed to create **plugInInterface via IOCreatePlugInInterfaceForService.", result);

}

if (NULL != pDevice->interface)

{

result = (*(pDevice->interface))->open (pDevice->interface, 0);

if (kIOReturnSuccess != result)

HIDReportErrorNum ("Failed to open pDevice->interface via open.", result);

else

(*(pDevice->interface))->setRemovalCallback (pDevice->interface, HIDRemovalCallback, pDevice, pDevice);

}

return result;

}

/* Closes and releases interface to device, should be done prior to exting application

* Note: will have no affect if device or interface do not exist

* application will "own" the device if interface is not closed

* (device may have to be plug and re-plugged in different location to get it working again without a restart)

*/

{

IOReturn result = kIOReturnSuccess;

if ((NULL != pDevice) && (NULL != pDevice->interface))

{

result = (*(pDevice->interface))->close (pDevice->interface);

if (kIOReturnNotOpen == result)

{

}

else if (kIOReturnSuccess != result)

HIDReportErrorNum ("Failed to close IOHIDDeviceInterface.", result);

result = (*(pDevice->interface))->Release (pDevice->interface);

if (kIOReturnSuccess != result)

HIDReportErrorNum ("Failed to release IOHIDDeviceInterface.", result);

pDevice->interface = NULL;

}

return result;

}

/* extracts actual specific element information from each element CF dictionary entry */

static void HIDGetElementInfo (CFTypeRef refElement, recElement *pElement)

{

long number;

CFTypeRef refType;

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementCookieKey));

if (refType && CFNumberGetValue (refType, kCFNumberLongType, &number))

pElement->cookie = (IOHIDElementCookie) number;

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementMinKey));

if (refType && CFNumberGetValue (refType, kCFNumberLongType, &number))

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementMaxKey));

if (refType && CFNumberGetValue (refType, kCFNumberLongType, &number))

/*

TODO: maybe should handle the following stuff somehow?

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementScaledMinKey));

if (refType && CFNumberGetValue (refType, kCFNumberLongType, &number))

pElement->scaledMin = number;

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementScaledMaxKey));

if (refType && CFNumberGetValue (refType, kCFNumberLongType, &number))

pElement->scaledMax = number;

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementSizeKey));

if (refType && CFNumberGetValue (refType, kCFNumberLongType, &number))

pElement->size = number;

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementIsRelativeKey));

if (refType)

pElement->relative = CFBooleanGetValue (refType);

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementIsWrappingKey));

if (refType)

pElement->wrapping = CFBooleanGetValue (refType);

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementIsNonLinearKey));

if (refType)

pElement->nonLinear = CFBooleanGetValue (refType);

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementHasPreferedStateKey));

if (refType)

pElement->preferredState = CFBooleanGetValue (refType);

refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementHasNullStateKey));

if (refType)

pElement->nullState = CFBooleanGetValue (refType);

*/

}

/* examines CF dictionary vlaue in device element hierarchy to determine if it is element of interest or a collection of more elements

* if element of interest allocate storage, add to list and retrieve element specific info

* if collection then pass on to deconstruction collection into additional individual elements

*/

static void HIDAddElement (CFTypeRef refElement, recDevice* pDevice)

{

recElement* element = NULL;

recElement** headElement = NULL;

long elementType, usagePage, usage;

CFTypeRef refElementType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementTypeKey));

CFTypeRef refUsagePage = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementUsagePageKey));

CFTypeRef refUsage = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementUsageKey));

if ((refElementType) && (CFNumberGetValue (refElementType, kCFNumberLongType, &elementType)))

{

/* look at types of interest */

if ((elementType == kIOHIDElementTypeInput_Misc) || (elementType == kIOHIDElementTypeInput_Button) ||

(elementType == kIOHIDElementTypeInput_Axis))

{

if (refUsagePage && CFNumberGetValue (refUsagePage, kCFNumberLongType, &usagePage) &&

refUsage && CFNumberGetValue (refUsage, kCFNumberLongType, &usage))

{

switch (usagePage) /* only interested in kHIDPage_GenericDesktop and kHIDPage_Button */

{

case kHIDPage_GenericDesktop:

{

switch (usage) /* look at usage to determine function */

{

case kHIDUsage_GD_X:

case kHIDUsage_GD_Y:

case kHIDUsage_GD_Z:

case kHIDUsage_GD_Rx:

case kHIDUsage_GD_Ry:

case kHIDUsage_GD_Rz:

case kHIDUsage_GD_Slider:

case kHIDUsage_GD_Dial:

case kHIDUsage_GD_Wheel:

element = (recElement *) NewPtrClear (sizeof (recElement));

if (element)

{

pDevice->axes++;

headElement = &(pDevice->firstAxis);

}

break;

case kHIDUsage_GD_Hatswitch:

element = (recElement *) NewPtrClear (sizeof (recElement));

if (element)

{

pDevice->hats++;

headElement = &(pDevice->firstHat);

}

break;

}

}

break;

case kHIDPage_Button:

element = (recElement *) NewPtrClear (sizeof (recElement));

if (element)

{

pDevice->buttons++;

headElement = &(pDevice->firstButton);

}

break;

default:

break;

}

}

}

else if (kIOHIDElementTypeCollection == elementType)

HIDGetCollectionElements ((CFMutableDictionaryRef) refElement, pDevice);

}

if (element && headElement) /* add to list */

{

pDevice->elements++;

if (NULL == *headElement)

*headElement = element;

else

{

recElement *elementPrevious, *elementCurrent;

elementCurrent = *headElement;

while (elementCurrent)

{

elementPrevious = elementCurrent;

elementCurrent = elementPrevious->pNext;

}

elementPrevious->pNext = element;

}

element->pNext = NULL;

HIDGetElementInfo (refElement, element);

}

}

/* collects information from each array member in device element list (each array memeber = element) */

static void HIDGetElementsCFArrayHandler (const void * value, void * parameter)

{

if (CFGetTypeID (value) == CFDictionaryGetTypeID ())

HIDAddElement ((CFTypeRef) value, (recDevice *) parameter);

}

/* handles retrieval of element information from arrays of elements in device IO registry information */

static void HIDGetElements (CFTypeRef refElementCurrent, recDevice *pDevice)

{

CFTypeID type = CFGetTypeID (refElementCurrent);

if (type == CFArrayGetTypeID()) /* if element is an array */

{

CFRange range = {0, CFArrayGetCount (refElementCurrent)};

/* CountElementsCFArrayHandler called for each array member */

CFArrayApplyFunction (refElementCurrent, range, HIDGetElementsCFArrayHandler, pDevice);

}

}

/* handles extracting element information from element collection CF types

* used from top level element decoding and hierarchy deconstruction to flatten device element list

*/

static void HIDGetCollectionElements (CFMutableDictionaryRef deviceProperties, recDevice *pDevice)

{

CFTypeRef refElementTop = CFDictionaryGetValue (deviceProperties, CFSTR(kIOHIDElementKey));

if (refElementTop)

HIDGetElements (refElementTop, pDevice);

}

/* use top level element usage page and usage to discern device usage page and usage setting appropriate vlaues in device record */

static void HIDTopLevelElementHandler (const void * value, void * parameter)

{

CFTypeRef refCF = 0;

if (CFGetTypeID (value) != CFDictionaryGetTypeID ())

return;

refCF = CFDictionaryGetValue (value, CFSTR(kIOHIDElementUsagePageKey));

if (!CFNumberGetValue (refCF, kCFNumberLongType, &((recDevice *) parameter)->usagePage))

SDL_SetError ("CFNumberGetValue error retrieving pDevice->usagePage.");

refCF = CFDictionaryGetValue (value, CFSTR(kIOHIDElementUsageKey));

if (!CFNumberGetValue (refCF, kCFNumberLongType, &((recDevice *) parameter)->usage))

SDL_SetError ("CFNumberGetValue error retrieving pDevice->usage.");

}

/* extracts device info from CF dictionary records in IO registry */

static void HIDGetDeviceInfo (io_object_t hidDevice, CFMutableDictionaryRef hidProperties, recDevice *pDevice)

{

CFMutableDictionaryRef usbProperties = 0;

io_registry_entry_t parent1, parent2;

/* Mac OS X currently is not mirroring all USB properties to HID page so need to look at USB device page also

* get dictionary for usb properties: step up two levels and get CF dictionary for USB properties

*/

if ((KERN_SUCCESS == IORegistryEntryGetParentEntry (hidDevice, kIOServicePlane, &parent1)) &&

(KERN_SUCCESS == IORegistryEntryGetParentEntry (parent1, kIOServicePlane, &parent2)) &&

(KERN_SUCCESS == IORegistryEntryCreateCFProperties (parent2, &usbProperties, kCFAllocatorDefault, kNilOptions)))

{

if (usbProperties)

{

CFTypeRef refCF = 0;

/* get device info

* try hid dictionary first, if fail then go to usb dictionary

*/

/* get product name */

refCF = CFDictionaryGetValue (hidProperties, CFSTR(kIOHIDProductKey));

if (!refCF)

refCF = CFDictionaryGetValue (usbProperties, CFSTR("USB Product Name"));

if (refCF)

{

if (!CFStringGetCString (refCF, pDevice->product, 256, CFStringGetSystemEncoding ()))

SDL_SetError ("CFStringGetCString error retrieving pDevice->product.");

}

/* get usage page and usage */

refCF = CFDictionaryGetValue (hidProperties, CFSTR(kIOHIDPrimaryUsagePageKey));

if (refCF)

{

if (!CFNumberGetValue (refCF, kCFNumberLongType, &pDevice->usagePage))

SDL_SetError ("CFNumberGetValue error retrieving pDevice->usagePage.");

refCF = CFDictionaryGetValue (hidProperties, CFSTR(kIOHIDPrimaryUsageKey));

if (refCF)

if (!CFNumberGetValue (refCF, kCFNumberLongType, &pDevice->usage))

SDL_SetError ("CFNumberGetValue error retrieving pDevice->usage.");

}

if (NULL == refCF) /* get top level element HID usage page or usage */

{

/* use top level element instead */

CFTypeRef refCFTopElement = 0;

refCFTopElement = CFDictionaryGetValue (hidProperties, CFSTR(kIOHIDElementKey));

{

/* refCFTopElement points to an array of element dictionaries */

CFRange range = {0, CFArrayGetCount (refCFTopElement)};

CFArrayApplyFunction (refCFTopElement, range, HIDTopLevelElementHandler, pDevice);

}

}

CFRelease (usbProperties);

}

else

SDL_SetError ("IORegistryEntryCreateCFProperties failed to create usbProperties.");

if (kIOReturnSuccess != IOObjectRelease (parent2))

SDL_SetError ("IOObjectRelease error with parent2.");

if (kIOReturnSuccess != IOObjectRelease (parent1))

SDL_SetError ("IOObjectRelease error with parent1.");

}

}

static recDevice *HIDBuildDevice (io_object_t hidDevice)

{

recDevice *pDevice = (recDevice *) NewPtrClear (sizeof (recDevice));

if (pDevice)

{

/* get dictionary for HID properties */

CFMutableDictionaryRef hidProperties = 0;

kern_return_t result = IORegistryEntryCreateCFProperties (hidDevice, &hidProperties, kCFAllocatorDefault, kNilOptions);

if ((result == KERN_SUCCESS) && hidProperties)

{

/* create device interface */

result = HIDCreateOpenDeviceInterface (hidDevice, pDevice);

if (kIOReturnSuccess == result)

{

HIDGetDeviceInfo (hidDevice, hidProperties, pDevice); /* hidDevice used to find parents in registry tree */

HIDGetCollectionElements (hidProperties, pDevice);

}

else

{

pDevice = NULL;

}

CFRelease (hidProperties);

}

else

{

pDevice = NULL;

}

}

return pDevice;

}

/* disposes of the element list associated with a device and the memory associated with the list

*/

static void HIDDisposeElementList (recElement **elementList)

{

recElement *pElement = *elementList;

while (pElement)

{

recElement *pElementNext = pElement->pNext;

DisposePtr ((Ptr) pElement);

pElement = pElementNext;

}

*elementList = NULL;

}

/* disposes of a single device, closing and releaseing interface, freeing memory fro device and elements, setting device pointer to NULL

* all your device no longer belong to us... (i.e., you do not 'own' the device anymore)

*/

static recDevice *HIDDisposeDevice (recDevice **ppDevice)

{

kern_return_t result = KERN_SUCCESS;

recDevice *pDeviceNext = NULL;

if (*ppDevice)

{

pDeviceNext = (*ppDevice)->pNext;

/* free element lists */

HIDDisposeElementList (&(*ppDevice)->firstAxis);

HIDDisposeElementList (&(*ppDevice)->firstButton);

HIDDisposeElementList (&(*ppDevice)->firstHat);

result = HIDCloseReleaseInterface (*ppDevice); /* function sanity checks interface value (now application does not own device) */

if (kIOReturnSuccess != result)

HIDReportErrorNum ("HIDCloseReleaseInterface failed when trying to dipose device.", result);

DisposePtr ((Ptr)*ppDevice);

*ppDevice = NULL;

}

return pDeviceNext;

}

/* Function to scan the system for joysticks.

* Joystick 0 should be the system default joystick.

* This function should return the number of available joysticks, or -1

* on an unrecoverable fatal error.

*/

int SDL_SYS_JoystickInit(void)

{

IOReturn result = kIOReturnSuccess;

mach_port_t masterPort = 0;

io_iterator_t hidObjectIterator = 0;

CFMutableDictionaryRef hidMatchDictionary = NULL;

recDevice *device, *lastDevice;

SDL_numjoysticks = 0;

{

SDL_SetError("Joystick: Device list already inited.");

return -1;

}

result = IOMasterPort (bootstrap_port, &masterPort);

if (kIOReturnSuccess != result)

{

SDL_SetError("Joystick: IOMasterPort error with bootstrap_port.");

return -1;

}

/* Set up a matching dictionary to search I/O Registry by class name for all HID class devices. */

hidMatchDictionary = IOServiceMatching (kIOHIDDeviceKey);

{

/* Add key for device type (joystick, in this case) to refine the matching dictionary. */

/* NOTE: we now perform this filtering later

UInt32 usagePage = kHIDPage_GenericDesktop;

UInt32 usage = kHIDUsage_GD_Joystick;

CFNumberRef refUsage = NULL, refUsagePage = NULL;

}

else

{

SDL_SetError("Joystick: Failed to get HID CFMutableDictionaryRef via IOServiceMatching.");

return -1;

}

/*/ Now search I/O Registry for matching devices. */

result = IOServiceGetMatchingServices (masterPort, hidMatchDictionary, &hidObjectIterator);

/* Check for errors */

{

SDL_SetError("Joystick: Couldn't create a HID object iterator.");

return -1;

}

{

gpDeviceList = NULL;

SDL_numjoysticks = 0;

return 0;

}

/* IOServiceGetMatchingServices consumes a reference to the dictionary, so we don't need to release the dictionary ref. */

/* build flat linked list of devices from device iterator */

gpDeviceList = lastDevice = NULL;

while ((ioHIDDeviceObject = IOIteratorNext (hidObjectIterator)))

{

/* build a device record */

device = HIDBuildDevice (ioHIDDeviceObject);

if (!device)

continue;

/* dump device object, it is no longer needed */

result = IOObjectRelease (ioHIDDeviceObject);

/* if (KERN_SUCCESS != result)

HIDReportErrorNum ("IOObjectRelease error with ioHIDDeviceObject.", result);

*/

/* Filter device list to non-keyboard/mouse stuff */

if ( (device->usagePage != kHIDPage_GenericDesktop) ||

((device->usage != kHIDUsage_GD_Joystick &&

device->usage != kHIDUsage_GD_GamePad &&

device->usage != kHIDUsage_GD_MultiAxisController)) ) {

/* release memory for the device */

HIDDisposeDevice (&device);

DisposePtr((Ptr)device);

continue;

}

/* Add device to the end of the list */

if (lastDevice)

lastDevice->pNext = device;

else

gpDeviceList = device;

lastDevice = device;

}

result = IOObjectRelease (hidObjectIterator); /* release the iterator */

/* Count the total number of devices we found */

device = gpDeviceList;

while (device)

{

SDL_numjoysticks++;

device = device->pNext;

}

return SDL_numjoysticks;

}

/* Function to get the device-dependent name of a joystick */

const char *SDL_SYS_JoystickName(int index)

{

recDevice *device = gpDeviceList;

for (; index > 0; index--)

device = device->pNext;

return device->product;

}

/* Function to open a joystick for use.

* The joystick to open is specified by the index field of the joystick.

* This should fill the nbuttons and naxes fields of the joystick structure.

* It returns 0, or -1 if there is an error.

*/

int SDL_SYS_JoystickOpen(SDL_Joystick *joystick)

{

recDevice *device = gpDeviceList;

int index;

for (index = joystick->index; index > 0; index--)

device = device->pNext;

joystick->hwdata = device;

joystick->name = device->product;

joystick->naxes = device->axes;

joystick->nhats = device->hats;

joystick->nballs = 0;

joystick->nbuttons = device->buttons;

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.

*/

void SDL_SYS_JoystickUpdate(SDL_Joystick *joystick)

{

recDevice *device = joystick->hwdata;

recElement *element;

SInt32 value;

int i;

if (device->removed) /* device was unplugged; ignore it. */

{

if (device->uncentered)

{

device->uncentered = 0;

/* Tell the app that everything is centered/unpressed... */

for (i = 0; i < device->axes; i++)

SDL_PrivateJoystickAxis(joystick, i, 0);

for (i = 0; i < device->buttons; i++)

SDL_PrivateJoystickButton(joystick, i, 0);

for (i = 0; i < device->hats; i++)

SDL_PrivateJoystickHat(joystick, i, SDL_HAT_CENTERED);

}

return;

}

element = device->firstAxis;

i = 0;

while (element)

{

value = HIDScaledCalibratedValue(device, element, -32768, 32767);

if ( value != joystick->axes[i] )

SDL_PrivateJoystickAxis(joystick, i, value);

element = element->pNext;

++i;

}

element = device->firstButton;

i = 0;

while (element)

{

value = HIDGetElementValue(device, element);

if (value > 1) /* handle pressure-sensitive buttons */

value = 1;

if ( value != joystick->buttons[i] )

SDL_PrivateJoystickButton(joystick, i, value);

element = element->pNext;

++i;

}

element = device->firstHat;

i = 0;

while (element)

{

value = HIDGetElementValue(device, element);

if (element->max == 3) /* 4 position hatswitch - scale up value */

value *= 2;

else if (element->max != 7) /* Neither a 4 nor 8 positions - fall back to default position (centered) */

value = -1;

switch(value)

{

case 0:

pos = SDL_HAT_UP;

break;

pos = SDL_HAT_RIGHTUP;

break;

pos = SDL_HAT_RIGHT;

break;

pos = SDL_HAT_RIGHTDOWN;

break;

pos = SDL_HAT_DOWN;

break;

pos = SDL_HAT_LEFTDOWN;

break;

pos = SDL_HAT_LEFT;

break;

pos = SDL_HAT_LEFTUP;

break;

default:

/* Every other value is mapped to center. We do that because some

* joysticks use 8 and some 15 for this value, and apparently

* there are even more variants out there - so we try to be generous.

*/

pos = SDL_HAT_CENTERED;

break;

}

if ( pos != joystick->hats[i] )

SDL_PrivateJoystickHat(joystick, i, pos);

element = element->pNext;

++i;

}

return;

}

/* Function to close a joystick after use */

void SDL_SYS_JoystickClose(SDL_Joystick *joystick)

{

/* Should we do anything here? */

return;

}

/* Function to perform any system-specific joystick related cleanup */

void SDL_SYS_JoystickQuit(void)

{

while (NULL != gpDeviceList)

gpDeviceList = HIDDisposeDevice (&gpDeviceList);

}

#endif /* SDL_JOYSTICK_IOKIT */