// First returns the first supported device attached to the host. Unlike Walk,
// the returned Device is opened automatically. This function exists primarily
// for testing.
func First() (*Device, error) {
handle := C.libusb_open_device_with_vid_pid(context, idVendor, idProduct)
if handle == nil {
return nil, errors.New("no devices found")
}
if err := C.libusb_claim_interface(handle, interfaceNum); err != C.LIBUSB_SUCCESS {
C.libusb_close(handle)
return nil, &libusbError{err}
}
return &Device{
dev: C.libusb_get_device(handle),
handle: handle,
}, nil
}
// OpenDeviceWithVidPid opens Device from specific VendorId and ProductId.
// If there are any errors, it'll returns at second value.
func (c *Context) OpenDeviceWithVidPid(vid, pid int) (*Device, error) {
handle := C.libusb_open_device_with_vid_pid(c.ctx, (C.uint16_t)(vid), (C.uint16_t)(pid))
if handle == nil {
return nil, ERROR_NOT_FOUND
}
dev := C.libusb_get_device(handle)
if dev == nil {
return nil, ERROR_NO_DEVICE
}
desc, err := newDescriptor(dev)
// return an error from nil-handle and nil-device
if err != nil {
return nil, err
}
device := newDevice(handle, desc)
return device, nil
}
// Get the underlying device for a handle.
func (h *DeviceHandle) Device() *Device {
return (*Device)(C.libusb_get_device(h.me()))
}
// Return a *Device for the given handle.
func (h *DeviceHandle) GetDevice() *Device {
return h.ctx.wrapDevice(C.libusb_get_device(h.handle))
}