sdl_sysjoystick.c

网络MPEG4IP流媒体开发源代码

/*
	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
	[e-mail]
*/

/* 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)
				pElement->minReport = hidEvent.value;
			if (hidEvent.value > pElement->maxReport)
				pElement->maxReport = hidEvent.value;
		}
	}

	// 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 ("Couldn誸 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->maxReport = pElement->min;
	refType = CFDictionaryGetValue (refElement, CFSTR(kIOHIDElementMaxKey));
	if (refType && CFNumberGetValue (refType, kCFNumberLongType, &number))
		pElement->max = number;
		pElement->minReport = 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 */