get mac serial for hdid

src/hardware_functions.cpp

@@ -50,10 +50,31 @@ QString get_hdid()
 }
 
 #elif defined __APPLE__
+#include <CoreFoundation/CoreFoundation.h>
+#include <IOKit/IOKitLib.h>
+
 QString get_hdid()
 {
-  //hdids are broken at this point anyways
-  return "just a mac passing by";
+    CFStringRef serial;
+        char buffer[64] = {0};
+        QString hdid;
+        io_service_t platformExpert = IOServiceGetMatchingService(kIOMasterPortDefault,
+                                                              IOServiceMatching("IOPlatformExpertDevice"));
+        if (platformExpert)
+        {
+            CFTypeRef serialNumberAsCFString = IORegistryEntryCreateCFProperty(platformExpert,
+                                                                           CFSTR(kIOPlatformSerialNumberKey),
+                                                                           kCFAllocatorDefault, 0);
+            if (serialNumberAsCFString) {
+                serial = (CFStringRef)serialNumberAsCFString;
+            }
+            if (CFStringGetCString(serial, buffer, 64, kCFStringEncodingUTF8)) {
+                hdid = buffer;
+            }
+
+            IOObjectRelease(platformExpert);
+        }
+        return hdid;
 }
 
 #else