Hi,
On Jul 20, 2016, at 2:15 AM, David Lawrie <david.dljunk@gmail.com> wrote:
>
> +static CFStringRef copy_device_name(IOHIDDeviceRef device)
> +{
> + CFTypeRef ref_name, ref_man;
> + CFStringRef name;
> + long prodID;
I prefer variables to be declared at the narrowest scope in which they're used.
> +
> + if (device)
> + {
> + assert(IOHIDDeviceGetTypeID() == CFGetTypeID(device));
> +
> + ref_name = IOHIDDeviceGetProperty(device, CFSTR(kIOHIDProductKey));
> +
> + if (ref_name && CFStringGetTypeID() == CFGetTypeID(ref_name))
> + name = CFStringCreateCopy(kCFAllocatorDefault,ref_name);
> + else
> + {
> + ref_man = IOHIDDeviceGetProperty(device, CFSTR(kIOHIDManufacturerKey));
I think it's simpler to use kIOHIDVendorIDKey with get_device_property_long(). Judging by the HID Calibrator code, kIOHIDManufacturerKey is not reliably available, but kIOHIDVendorIDKey should be. It's also pretty fundamental to USB/HID.
> + prodID = get_device_property_long(device, CFSTR(kIOHIDProductIDKey));
> +
> + if(ref_man && CFStringGetTypeID() == CFGetTypeID(ref_man))
> + name = CFStringCreateWithFormat(kCFAllocatorDefault, NULL, CFSTR("%@ %lu"), ref_man, prodID);
Better to format vendor and product IDs using "0x%04lx" since that's how they are usually represented (e.g. within HID Calibrator windows and System Profiler). (Yes, I realize that Copy_DeviceName() which I cited previously formats them as decimal.)
Thanks for persevering in the face of my picky-ness. :)
-Ken