iCPU

The Swift implementation of CPU-Identifier by @hirakujira.

Why a Swift version?

I "translated" CPU-Identifier to a pure Swift version because I'd like to write some code involving C function pointers in Swift 2.0.

It was a huge pain to work with C function pointers in Swift 1.x, with the improvements comes with Swift 2.0, you may already find out that it is much easier to work with C function pointers in places like callbacks (e.g. CVDisplayLinkSetOutputCallback, FSEventStreamCreate, etc).

But I'm still curious about what would it be like to work with something more dynamic.

In this project, we have to use dlsym to get the function pointer of a private function hidden in libMobileGestalt.dylib, after that, we call the function with a CFStringRef as parameter and expect a return value of a CFStringRef.

As dlsym returns UnsafeMutablePointer<Void> (or void * in C), it would be painful to find a way to call the actual function in Swift 1.x. But in Swift 2.0, a simple unsafeBitcast will do the trick.

typealias MGCopyAnswer = (@convention(c) (CFStringRef) -> CFStringRef)

let copyAnswerSymbol = dlsym(gestalt, "MGCopyAnswer".UTF8CString)
let copyAnswerFunction = unsafeBitCast(copyAnswerSymbol, MGCopyAnswer.self)

let result = copyAnswerFunction("HardwarePlatform") as String

Though I have scratched my head for a few hours until I've found the @convention(c) keyword in the Documents, the example shows that it is very clean and easy to use C function pointers in Swift 2.0.

Build

• Xcode 7.0 and above
• Swift 2.0 and above

Acknowledgement

This is a Swift implementation of CPU-Identifier by @hirakujira.

The method to retrieve HardwarePlatform and the map between HardwarePlatform and CPU-Type are borrowed from CPU-Identifier.