cfprefs.swift

@_transparent private func CFDictionaryGetValue(_ dictionary: CFDictionary, _ key: CFString) -> UnsafeRawPointer? {
    CFDictionaryGetValue(dictionary, Unmanaged.passUnretained(key).toOpaque())
}

@_transparent private func CFDictionaryUnwrap(_ type: CFTypeRef) -> CFDictionary? {
    guard CFGetTypeID(type) == CFDictionaryGetTypeID() else {
        return nil
    }
    return unsafeBitCast(type, to: CFDictionary.self)
}

@_transparent private func CFBooleanUnwrap(_ type: CFTypeRef) -> CFBoolean? {
    guard CFGetTypeID(type) == CFBooleanGetTypeID() else {
        return nil
    }
    return unsafeBitCast(type, to: CFBoolean.self)
}

@_transparent private func CFDictionaryGetType(_ dictionary: CFDictionary, _ key: CFString) -> CFTypeRef? {
    guard let returnValue = CFDictionaryGetValue(dictionary, key) else {
        return nil
    }
    return Unmanaged.fromOpaque(returnValue).takeUnretainedValue()
}

@_transparent private func CFDictionaryGetDictionary(_ dictionary: CFDictionary, _ key: CFString) -> CFDictionary? {
    guard let type = CFDictionaryGetType(dictionary, key) else {
        return nil
    }
    return CFDictionaryUnwrap(type)
}

@_transparent private func CFDictionaryGetBoolean(_ dictionary: CFDictionary, _ key: CFString) -> CFBoolean? {
    guard let type = CFDictionaryGetType(dictionary, key) else {
        return nil
    }
    return CFBooleanUnwrap(type)
}

private let kCFDictionaryEmpty = CFDictionaryCreate(kCFAllocatorSystemDefault, nil, nil, 0, nil, nil)!

private func CFDictionaryCreateMutable() -> CFMutableDictionary {
    CFDictionaryCreateMutable(kCFAllocatorSystemDefault, 0, [kCFTypeDictionaryKeyCallBacks], [kCFTypeDictionaryValueCallBacks])
}

private func CFDictionarySetValue(_ dictionary: CFMutableDictionary, _ key: CFTypeRef, _ value: CFTypeRef) {
    CFDictionarySetValue(dictionary, Unmanaged.passUnretained(key).toOpaque(), Unmanaged.passUnretained(value).toOpaque())
}

private func CFDictionaryAddValue(_ dictionary: CFMutableDictionary, _ key: CFTypeRef, _ value: CFTypeRef) {
    CFDictionaryAddValue(dictionary, Unmanaged.passUnretained(key).toOpaque(), Unmanaged.passUnretained(value).toOpaque())
}

private func CFDictionaryContainsKey(_ dictionary: CFDictionary, _ key: CFTypeRef) -> Bool {
    CFDictionaryContainsKey(dictionary, Unmanaged.passUnretained(key).toOpaque())
}