OSX JoyTest

main.m

//
//  main.m
//  JoyTest
//
//  Created by Daniel Leong on 12/18/14.
//  Copyright (c) 2014 Daniel Leong. All rights reserved.
//

#import <Foundation/Foundation.h>

#import <IOKit/hid/IOHIDManager.h>

enum
{
    kJoystickGammaTableSize = 256
};

static void HandleDeviceMatchingCallback(void * inContext, IOReturn inResult, void* inSender, IOHIDDeviceRef  inIOHIDDeviceRef);
static void HandleInputValueCallback(void * inContext, IOReturn inResult, void* inSender, IOHIDValueRef  inIOHIDValueRef);
static void HandleDeviceRemovalCallback(void * inContext, IOReturn inResult, void* inSender, IOHIDDeviceRef  inIOHIDDeviceRef);
static void HandleDevice(IOHIDDeviceRef inIOHIDDeviceRef);

static int AxisIndex(uint32_t page, uint32_t usage);

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        // insert code here...
        NSLog(@"Hello, World!");
        
        IOHIDManagerRef hidManager = IOHIDManagerCreate(kCFAllocatorDefault, kIOHIDOptionsTypeNone);
        IOHIDManagerSetDeviceMatching(hidManager, NULL);
        
        IOHIDManagerRegisterDeviceMatchingCallback(hidManager, HandleDeviceMatchingCallback, NULL);
        IOHIDManagerRegisterDeviceRemovalCallback(hidManager, HandleDeviceRemovalCallback, NULL);
        
        IOHIDManagerScheduleWithRunLoop(hidManager, CFRunLoopGetMain(), kCFRunLoopDefaultMode);
        IOReturn iores = IOHIDManagerOpen(hidManager, kIOHIDOptionsTypeNone);
        if (iores != kIOReturnSuccess) {
            NSLog(@"Cannot open HID manager; joystick support will not function.");
        }
        else {
            NSLog(@"Opened!");
        }
        
//        CFSetRef set = IOHIDManagerCopyDevices(hidManager);
//        CFIndex count = CFSetGetCount(set);
//        const IOHIDDeviceRef results[count];
//        
//        CFSetGetValues(set, (const void **)&results);
//        for (int i=0; i < count; i++) {
////            NSLog(@"%s", results[i]);
//            CFStringRef ref = IOHIDDeviceGetProperty(results[i],
//                                                     CFSTR(kIOHIDManufacturerKey));
//            NSString *manufacturer = (__bridge NSString *) ref;
////            long len = CFStringGetLength(ref);
////            char str[len];
////            CFStringGetCString(ref, str, len, )
//
//            if ([manufacturer containsString:@"ustmaster"]) {
//                HandleDevice(results[i]);
//            }
//        }

        
        CFRunLoopRun();
    }
    
    return 0;
}

static void HandleDevice(IOHIDDeviceRef device) {
    
    NSLog(@"Discovered device!: %@", device);

    IOOptionBits options = kIOHIDOptionsTypeNone;
    IOReturn result = IOHIDDeviceOpen(device, options);
    if (result != kIOReturnSuccess) {
        NSLog(@"result: %d", result);
        return;
    }
    
    NSDictionary *dict = [[NSDictionary alloc] init];
    IOHIDDeviceRegisterInputValueCallback(device, HandleInputValueCallback, (__bridge void *)(dict));
    
    CFArrayRef elementList = IOHIDDeviceCopyMatchingElements(device, NULL, 0L);
    if (elementList != NULL)
    {
        
        CFIndex idx, count = CFArrayGetCount(elementList);
        
        for (idx = 0; idx < count; idx++)
        {
            IOHIDElementRef element = (IOHIDElementRef)CFArrayGetValueAtIndex(elementList, idx);
            IOHIDElementType elementType = IOHIDElementGetType(element);
            if (elementType > kIOHIDElementTypeInput_ScanCodes)
            {
                continue;
            }
            IOHIDElementCookie elementCookie = IOHIDElementGetCookie(element);
            uint32_t usagePage = IOHIDElementGetUsagePage(element);
            uint32_t usage = IOHIDElementGetUsage(element);
            uint32_t min = (uint32_t)IOHIDElementGetPhysicalMin(element);
            uint32_t max = (uint32_t)IOHIDElementGetPhysicalMax(element);
            NSString *name = (__bridge NSString *)IOHIDElementGetProperty(element, CFSTR(kIOHIDElementNameKey)) ?: @"unnamed";
            IOHIDValueRef ref;
            IOHIDDeviceGetValue(device, element, &ref);
            if (ref) {
        		CFIndex intValue = IOHIDValueGetIntegerValue(ref);
                if (intValue) {
                    NSLog(@"#%ld, %@ - usage %d:%d, cookie %d, range %d-%d", idx, name, usagePage, usage, (int) elementCookie, min, max);
                    NSLog(@" --> value=%ld", intValue);
                }
            }
        }
        
        CFRelease(elementList);
    }
}

static void HandleDeviceMatchingCallback(void * inContext, IOReturn inResult, void* inSender, IOHIDDeviceRef device)
{
    CFStringRef ref = IOHIDDeviceGetProperty(device, CFSTR(kIOHIDManufacturerKey));
    NSString *manufacturer = (__bridge NSString *) ref;
//            long len = CFStringGetLength(ref);
//            char str[len];
//            CFStringGetCString(ref, str, len, )

    if ([manufacturer containsString:@"ustmaster"]) {
        HandleDevice(device);
    }
}



static void HandleInputValueCallback(void * inContext, IOReturn inResult, void* inSender, IOHIDValueRef  value)
{
    IOHIDElementRef element = IOHIDValueGetElement(value);
    IOHIDDeviceRef device = IOHIDElementGetDevice(element);
    NSString *deviceName = (__bridge NSString *)(IOHIDDeviceGetProperty(device, CFSTR(kIOHIDProductKey)));
    
    NSString *name = (__bridge NSString *)(IOHIDElementGetName(element));
    IOHIDElementCookie cookie = IOHIDElementGetCookie(element);
    
    uint32_t usagePage = IOHIDElementGetUsagePage(element);
    uint32_t usage = IOHIDElementGetUsage(element);
    int axisIndex = AxisIndex(usagePage, usage);
    
    if (axisIndex >= 0) {
        long intValue = IOHIDValueGetIntegerValue(value);
        NSLog(@">> (%d) %@.%@%u -> %ld", axisIndex, deviceName, name, cookie, intValue);
        

        {
            CFIndex intValue = IOHIDValueGetIntegerValue(value);
            CFIndex min = IOHIDElementGetLogicalMin(element);
            CFIndex max = IOHIDElementGetLogicalMax(element);
            float axisValue = (float)(intValue - min) / (float)(max + 1 - min);
            
            // Note: this is designed so gammaIndex == intValue if min == 0 and max == kJoystickGammaTableSize - 1 (the common case).
            unsigned gammaIndex = floor(axisValue * kJoystickGammaTableSize);
            
            NSLog(@"value=%f -> %d", axisValue, gammaIndex);
            
            
//            evt.value = gammaTable[gammaIndex];
        }
        
            
//        {
//            CFTypeRef o = IOHIDDeviceGetProperty(
//                                                 device, CFSTR(kIOHIDDeviceUsagePairsKey));
//            printf("\tkIOHIDDeviceUsagePairsKey = %p\n", o);
//            CFShow(o);
//    //        uint32_t usagePage = (IOHIDDeviceGetProperty(device, CFSTR(kIOHIDDeviceUsagePageKey)));
//    //        if (usagePage == kHIDPage_GenericDesktop) {
//    //            NSLog(@"GEneric desktop!");
//    //        } else {
//    //            NSLog(@"GEneric desktop? %d", usagePage);
//    //        }
//        }

    }
}

static int AxisIndex(uint32_t page, uint32_t usage)
{
    /*
     Map axis-like HID usages to SDL-like axis indices. These are all the
     commonly used joystick axes according to Microsoft's DirectInput
     documentation (hey, you've got to get your info somewhere).
     
     GD_Slider, GD_Dial, DG_Wheel and Sim_Throttle are actually distinct;
     unlike the others, they're uncentered. (By implication,
     IOHIDElementHasPreferredState() should be false.) This should, in
     particular, be considered when mapping to the throttle: centered axes
     should provide relative input (for gamepads), while uncentered ones
     should provide absolute input. Since that festering pool of pus, SDL,
     can't make this distinction, OOJoystickManager can't either (yet).
     -- Ahruman 2011-01-04
     */
    
    switch (page)
    {
        case kHIDPage_GenericDesktop:
            switch (usage)
        {
            case kHIDUsage_GD_X: return 0;
            case kHIDUsage_GD_Y: return 1;
            case kHIDUsage_GD_Z: return 2;
            case kHIDUsage_GD_Rx: return 3;
            case kHIDUsage_GD_Ry: return 4;
            case kHIDUsage_GD_Rz: return 5;
            case kHIDUsage_GD_Slider: return 6;
            case kHIDUsage_GD_Dial: return 7;
            case kHIDUsage_GD_Wheel: return 8;
        }
            break;
            
        case kHIDPage_Simulation:
            switch (usage)
        {
            case kHIDUsage_Sim_Throttle:
                return 9;
        }
    }
    
    // Negative numbers indicate non-axis.
    return -1;
}

static void HandleDeviceRemovalCallback(void * inContext, IOReturn inResult, void* inSender, IOHIDDeviceRef  inIOHIDDeviceRef)
{
    NSLog(@"Removed");
}