Logo Search packages:      
Sourcecode: whitedune version File versions  Download package

SDL_sysjoystick.c

/*
      SDL - Simple DirectMedia Layer
      Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  Sam Lantinga

      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
      slouken@libsdl.org
*/

/* SDL joystick driver for Darwin / MacOS X, based on the IOKit HID API */
/* Written 2001 by Max Horn */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <ctype.h>
#include <sys/errno.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
/* The header was moved here in MacOS X 10.1 */
#include <Kernel/IOKit/hidsystem/IOHIDUsageTables.h>
#endif
#include <IOKit/hid/IOHIDLib.h>
#include <IOKit/hid/IOHIDKeys.h>
#include <CoreFoundation/CoreFoundation.h>
#include <Carbon/Carbon.h> /* for NewPtrClear, DisposePtr */

#include "SDL_error.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
/*
      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
*/

      /* runtime variables used for auto-calibration */
      long minReport;                                       // min returned value
      long maxReport;                                       // max returned value
      
      struct recElement * pNext;                      // next element in list
};
typedef struct recElement recElement;

struct joystick_hwdata
{
      IOHIDDeviceInterface ** interface;        // interface to device, NULL = no interface

      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;

      struct joystick_hwdata* pNext;                  // next device
};
typedef struct joystick_hwdata recDevice;


/* Linked list of all available devices */
static recDevice *gpDeviceList = NULL;


void HIDReportErrorNum (char * strError, long numError)
{
      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
 */

SInt32 HIDGetElementValue (recDevice *pDevice, recElement *pElement)
{
      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) {
#ifdef DEBUG
                                fprintf(stderr,"minReport old value %ld\n",pElement->minReport);
#endif
                        pElement->minReport = hidEvent.value;
#ifdef DEBUG
                                fprintf(stderr,"minReport new value %ld\n",pElement->minReport);
#endif
                        }
                  if (hidEvent.value > pElement->maxReport) {
#ifdef DEBUG
                                fprintf(stderr,"maxReport old value %ld\n",pElement->maxReport);
#endif
                        pElement->maxReport = hidEvent.value;
#ifdef DEBUG
                                fprintf(stderr,"maxReport new value %ld\n",pElement->maxReport);
#endif
                        }

            }
      }

      // auto user scale
      return hidEvent.value;
}

/* similiar to HIDGetElementValue, but auto-calibrates the value before returning it */

SInt32 HIDCalibratedValue (recDevice *pDevice, recElement *pElement)
{
      float deviceScale = pElement->max - pElement->min;
      float readScale = pElement->maxReport - pElement->minReport;
      SInt32 value = HIDGetElementValue(pDevice, pElement);
      if (readScale == 0)
            return value; // no scaling at all
      else
            return ((value - pElement->minReport) * deviceScale / readScale) + pElement->min;
}

/* similiar to HIDCalibratedValue but calibrates to an arbitrary scale instead of the elements default scale */

SInt32 HIDScaledCalibratedValue (recDevice *pDevice, recElement *pElement, long min, long max)
{
      float deviceScale = max - min;
      float readScale = pElement->maxReport - pElement->minReport;
      SInt32 value = HIDGetElementValue(pDevice, pElement);
      if (readScale == 0)
            return value; // no scaling at all
      else
            return ((value - pElement->minReport) * deviceScale / readScale) + min;
}

/* 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 HIDCreateOpenDeviceInterface (io_object_t hidDevice, recDevice *pDevice)
{
      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)
            {
                  // Call a method of the intermediate plug-in to create the device interface
                  plugInResult = (*ppPlugInInterface)->QueryInterface (ppPlugInInterface,
                                                CFUUIDGetUUIDBytes (kIOHIDDeviceInterfaceID), (void *) &(pDevice->interface));
                  if (S_OK != plugInResult)
                        HIDReportErrorNum ("CouldnŐt 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);
      }
      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 HIDCloseReleaseInterface (recDevice *pDevice)
{
      IOReturn result = kIOReturnSuccess;
      
      if ((NULL != pDevice) && (NULL != pDevice->interface))
      {
            // close the interface
            result = (*(pDevice->interface))->close (pDevice->interface);
            if (kIOReturnNotOpen == result)
            {
                  //  do nothing as device was not opened, thus can't be closed
            }
            else if (kIOReturnSuccess != result)
                  HIDReportErrorNum ("Failed to close IOHIDDeviceInterface.", result);
            //release the interface
            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)) {
            pElement->min = number;
            pElement->minReport = pElement->min;
        }
      refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementMaxKey));
      if (refType && CFNumberGetValue (refType, kCFNumberLongType, &number)) {
            pElement->max = number;
            pElement->maxReport = pElement->max;
        }
/*
      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:
                                                      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
                  {
                        DisposePtr((Ptr)pDevice);
                        pDevice = NULL;
                  }
                  CFRelease (hidProperties);
            }
            else
            {
                  DisposePtr((Ptr)pDevice);
                  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)
      {
            // save next device prior to disposing of this device
            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 = NULL;
      io_iterator_t hidObjectIterator = NULL;
      CFMutableDictionaryRef hidMatchDictionary = NULL;
      recDevice *device, *lastDevice;
      io_object_t ioHIDDeviceObject = NULL;
      
      SDL_numjoysticks = 0;
      
      if (NULL != gpDeviceList)
      {
            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);
      if ((hidMatchDictionary != NULL))
      {
            /* 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;

            refUsage = CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &usage);
            CFDictionarySetValue (hidMatchDictionary, CFSTR (kIOHIDPrimaryUsageKey), refUsage);
            refUsagePage = CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &usagePage);
            CFDictionarySetValue (hidMatchDictionary, CFSTR (kIOHIDPrimaryUsagePageKey), refUsagePage);
            */
      }
      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 */
      if (kIOReturnSuccess != result)
      {
            SDL_SetError("Joystick: Couldn't create a HID object iterator.");
            return -1;
      }
      if (NULL == hidObjectIterator) /* there are no joysticks */
      {
            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_Keyboard ||
                  device->usage == kHIDUsage_GD_Mouse)) {
            
                  /* 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;
      
      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 != joystick->buttons[i] )
                  SDL_PrivateJoystickButton(joystick, i, value);
            element = element->pNext;
            ++i;
      }
      
      element = device->firstHat;
      i = 0;
      while (element)
      {
            Uint8 pos = 0;

            value = HIDGetElementValue(device, element);
            switch(value)
            {
                  case 0:
                        pos = SDL_HAT_CENTERED;
                        break;
                  case 1:
                        pos = SDL_HAT_UP;
                        break;
                  case 2:
                        pos = SDL_HAT_RIGHTUP;
                        break;
                  case 3:
                        pos = SDL_HAT_RIGHT;
                        break;
                  case 4:
                        pos = SDL_HAT_RIGHTDOWN;
                        break;
                  case 5:
                        pos = SDL_HAT_DOWN;
                        break;
                  case 6:
                        pos = SDL_HAT_LEFTDOWN;
                        break;
                  case 7:
                        pos = SDL_HAT_LEFT;
                        break;
                  case 8:
                        pos = SDL_HAT_LEFTUP;
                        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);
}

Generated by  Doxygen 1.6.0   Back to index