Example #1
0
func TestEnum(t *testing.T) {
	c := NewContext()
	defer c.Close()
	c.Debug(0)

	logDevice := func(t *testing.T, desc *Descriptor) {
		t.Logf("%03d.%03d %s", desc.Bus, desc.Address, usbid.Describe(desc))
		t.Logf("- Protocol: %s", usbid.Classify(desc))

		for _, cfg := range desc.Configs {
			t.Logf("- %s:", cfg)
			for _, alt := range cfg.Interfaces {
				t.Logf("  --------------")
				for _, iface := range alt.Setups {
					t.Logf("  - %s", iface)
					t.Logf("    - %s", usbid.Classify(iface))
					for _, end := range iface.Endpoints {
						t.Logf("    - %s (packet size: %d bytes)", end, end.MaxPacketSize)
					}
				}
			}
			t.Logf("  --------------")
		}
	}

	descs := []*Descriptor{}
	devs, err := c.ListDevices(func(desc *Descriptor) bool {
		logDevice(t, desc)
		descs = append(descs, desc)
		return true
	})
	defer func() {
		for _, d := range devs {
			d.Close()
		}
	}()
	if err != nil {
		t.Fatalf("list: %s", err)
	}

	if got, want := len(devs), len(descs); got != want {
		t.Fatalf("len(devs) = %d, want %d", got, want)
	}

	for i := range devs {
		if got, want := devs[i].Descriptor, descs[i]; got != want {
			t.Errorf("dev[%d].Descriptor = %p, want %p", i, got, want)
		}
	}
}
Example #2
0
func main() {
	flag.Parse()

	// Only one context should be needed for an application.  It should always be closed.
	ctx := usb.NewContext()
	defer ctx.Close()

	// Debugging can be turned on; this shows some of the inner workings of the libusb package.
	ctx.Debug(*debug)

	// ListDevices is used to find the devices to open.
	devs, err := ctx.ListDevices(func(desc *usb.Descriptor) bool {
		// The usbid package can be used to print out human readable information.
		fmt.Printf("%03d.%03d %s:%s %s\n", desc.Bus, desc.Address, desc.Vendor, desc.Product, usbid.Describe(desc))
		fmt.Printf("  Protocol: %s\n", usbid.Classify(desc))

		// The configurations can be examined from the Descriptor, though they can only
		// be set once the device is opened.  All configuration references must be closed,
		// to free up the memory in libusb.
		for _, cfg := range desc.Configs {
			// This loop just uses more of the built-in and usbid pretty printing to list
			// the USB devices.
			fmt.Printf("  %s:\n", cfg)
			for _, alt := range cfg.Interfaces {
				fmt.Printf("    --------------\n")
				for _, iface := range alt.Setups {
					fmt.Printf("    %s\n", iface)
					fmt.Printf("      %s\n", usbid.Classify(iface))
					for _, end := range iface.Endpoints {
						fmt.Printf("      %s\n", end)
					}
				}
			}
			fmt.Printf("    --------------\n")
		}

		// After inspecting the descriptor, return true or false depending on whether
		// the device is "interesting" or not.  Any descriptor for which true is returned
		// opens a Device which is retuned in a slice (and must be subsequently closed).
		return false
	})

	// All Devices returned from ListDevices must be closed.
	defer func() {
		for _, d := range devs {
			d.Close()
		}
	}()

	// ListDevices can occaionally fail, so be sure to check its return value.
	if err != nil {
		log.Fatalf("list: %s", err)
	}

	for _, dev := range devs {
		// Once the device has been selected from ListDevices, it is opened
		// and can be interacted with.
		_ = dev
	}
}