gssc.mm

   1 #import <GraphicsServices/GraphicsServices.h>
   2 #import <UIKit/UIKit.h>
   3 #include <stdio.h>
   4 #include <dlfcn.h>
   5 #include <objc/runtime.h>
   6
   7 static CFArrayRef (*$GSSystemCopyCapability)(CFStringRef);
   8 static CFArrayRef (*$GSSystemGetCapability)(CFStringRef);
   9
  10 void OnGSCapabilityChanged(
  11     CFNotificationCenterRef center,
  12     void *observer,
  13     CFStringRef name,
  14     const void *object,
  15     CFDictionaryRef info
  16 ) {
  17     CFRunLoopStop(CFRunLoopGetCurrent());
  18 }
  19
  20 int main(int argc, char *argv[]) {
  21     dlopen("/System/Library/Frameworks/Foundation.framework/Foundation", RTLD_GLOBAL | RTLD_LAZY);
  22     dlopen("/System/Library/PrivateFrameworks/GraphicsServices.framework/GraphicsServices", RTLD_GLOBAL | RTLD_LAZY);
  23
  24     NSAutoreleasePool *pool = [[objc_getClass("NSAutoreleasePool") alloc] init];
  25
  26     NSString *name = nil;
  27
  28     if (argc == 2)
  29         name = [objc_getClass("NSString") stringWithUTF8String:argv[0]];
  30     else if (argc > 2) {
  31         fprintf(stderr, "usage: %s [capability]\n", argv[0]);
  32         exit(1);
  33     }
  34
  35     $GSSystemCopyCapability = reinterpret_cast<CFArrayRef (*)(CFStringRef)>(dlsym(RTLD_DEFAULT, "GSSystemCopyCapability"));
  36     $GSSystemGetCapability = reinterpret_cast<CFArrayRef (*)(CFStringRef)>(dlsym(RTLD_DEFAULT, "GSSystemGetCapability"));
  37
  38     CFNotificationCenterAddObserver(
  39         CFNotificationCenterGetDarwinNotifyCenter(),
  40         NULL,
  41         &OnGSCapabilityChanged,
  42         CFSTR("GSCapabilitiesChanged"),
  43         NULL,
  44         NULL
  45     );
  46
  47     const NSArray *capability;
  48
  49     for (;;) {
  50         if ($GSSystemCopyCapability != NULL) {
  51             capability = reinterpret_cast<const NSArray *>((*$GSSystemCopyCapability)(reinterpret_cast<CFStringRef>(name)));
  52             if (capability != nil)
  53                 capability = [capability autorelease];
  54         } else if ($GSSystemGetCapability != NULL) {
  55             capability = reinterpret_cast<const NSArray *>((*$GSSystemGetCapability)(reinterpret_cast<CFStringRef>(name)));
  56         } else {
  57             capability = nil;
  58             break;
  59         }
  60
  61         if (capability != nil)
  62             break;
  63
  64         CFRunLoopRun();
  65     }
  66
  67     printf("%s\n", capability == nil ? "(null)" : [[capability description] UTF8String]);
  68
  69     [pool release];
  70
  71     return 0;
  72 }