sdl_sysjoystick.c

MPEG-4编解码的实现(包括MPEG4视音频编解码)

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;
	UInt32 usagePage = kHIDPage_GenericDesktop;
	UInt32 usage = kHIDUsage_GD_Joystick; /* We probably also should check for gamepads? */
	
	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) && (usagePage) && (usage))
	{
		/* Add key for device type (joystick, in this case) to refine the matching dictionary. */
		CFNumberRef refUsage = NULL, refUsagePage = NULL;

		refUsage = CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &usagePage);
		CFDictionarySetValue (hidMatchDictionary, CFSTR (kIOHIDPrimaryUsageKey), refUsage);
		refUsagePage = CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &usage);
		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) || (NULL == hidObjectIterator))
	{
		SDL_SetError("Joystick: Couldn't create a HID object iterator.");
		return -1;
	}
	/* 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);
		/* 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);
}