AppleProxShim

AppleProxShim is the IOHIDService that controls the device's proximity sensor. By default, this service is enabled only from within applications that have called the high-level method -[UIApplication setProximitySensingEnabled:].

You can intercept the service to manually enable the proximity sensor and assign a callback action for the proximity events, even when on SpringBoard.

To turn on the sensor, you need to change the service's default ReportInterval from 0 to a higher number. For more information about IOHID, see IOHIDFamily

General characteristics

Kernel Extension	IOHIDFamily
Service name	AppleProxShim
Parent Service	AppleCT700
IOProviderClass	AppleARMIICDevice
HIDServiceSupport	Yes
Default ReportInterval	0
PrimaryUsage	8
PrimaryUsagePage	65280

Example

#include <IOKit/hid/IOHIDEventSystem.h>
#include <stdio.h>

void handle_event (void* target, void* refcon, IOHIDServiceRef service, IOHIDEventRef event) {
  
  if (IOHIDEventGetType(event)==14){ // Proximity Event Received
		

                int proximityValue=IOHIDEventGetIntegerValue(event, (IOHIDEventField)917504); // Get the value of the ProximityChanged Field (0 or 64)
            
                // Call dimScreen on SpringBoard to simulate the original proximity effect, or use a reaction of your choice
		int (*SBSSpringBoardServerPort)() = (int (*)())dlsym(RTLD_DEFAULT, "SBSSpringBoardServerPort");
		int port = SBSSpringBoardServerPort(); 
		void (*_SBDimScreen)(int _port,BOOL shouldDim) = (void (*)(int _port,BOOL shouldDim))dlsym(RTLD_DEFAULT, "SBDimScreen");

		BOOL dim = proximityValue == 0 ? NO : YES;
		
		_SBDimScreen(port,dim); 
		
   }
 
}

  

int main () {
  // Create and open an event system.
  IOHIDEventSystemRef system = IOHIDEventSystemCreate(NULL);
  
  // set the PrimaryUsagePage and PrimaryUsage that the AppleProxShim service uses
  int page = 65280;
  int usage = 8;
	
  // Create a dictionary to match the service with
  CFNumberRef nums[2];
  CFStringRef keys[2];
  keys[0] = CFStringCreateWithCString(0, "PrimaryUsagePage", 0);
  keys[1] = CFStringCreateWithCString(0, "PrimaryUsage", 0);
  nums[0] = CFNumberCreate(0, kCFNumberSInt32Type, &page);
  nums[1] = CFNumberCreate(0, kCFNumberSInt32Type, &usage);
  CFDictionaryRef dict = CFDictionaryCreate(0, (const void**)keys, (const void**)nums, 2, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
  // Get the total of matching services with the above criteria
  CFArrayRef srvs = (CFArrayRef)IOHIDEventSystemCopyMatchingServices(system, dict, 0, 0, 0,0);
  
  // Get the service
  IOHIDServiceRef serv = (IOHIDServiceRef)CFArrayGetValueAtIndex(srvs, 0);
  int interval = 1 ;

  // Set an interval of 1 , to activate the sensor  
  IOHIDServiceSetProperty((IOHIDServiceRef)serv, CFSTR("ReportInterval"), CFNumberCreate(0, kCFNumberSInt32Type, &interval));
  
  IOHIDEventSystemOpen(system, handle_event, NULL, NULL, NULL);
  printf("HID Event system should now be running. Hit enter to quit any time.\n");
  getchar();
 
  IOHIDEventSystemClose(system, NULL);
  CFRelease(system);
  return 0;
}

Note

The lockscreen has its own Dim Timer, so when in lockscreen the SBDimScreen event will only dim it, but will not undim. Test in SpringBoard, unlocked, for better results.

References

• Headers for IOHID: http://github.com/kennytm/iphone-private-frameworks/tree/master/IOKit/hid