Added first implementation of USB DFU probe

Author: cmaglie

go.mod

@@ -2,10 +2,12 @@ module github.com/arduino/dfu-discovery
 
 go 1.19
 
-require github.com/arduino/pluggable-discovery-protocol-handler/v2 v2.1.1
+require (
+	github.com/arduino/go-properties-orderedmap v1.7.1
+	github.com/arduino/pluggable-discovery-protocol-handler/v2 v2.1.1
+)
 
 require (
 	github.com/arduino/go-paths-helper v1.8.0 // indirect
-	github.com/arduino/go-properties-orderedmap v1.7.1 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 )

main.c

@@ -38,4 +38,8 @@ const char *libusbOpen() {
 void libusbClose() {
   libusb_exit(ctx);
   ctx = NULL;
-}
+}
+
+void dfuProbeDevices() {
+  probe_devices(ctx);
+}

main.go

@@ -13,13 +13,16 @@ char *get_path(libusb_device *dev);
 // Defined in main.c
 const char *libusbOpen();
 void libusbClose();
+void dfuProbeDevices();
 */
 import "C"
 
 import (
 	"fmt"
 	"os"
+	"time"
 
+	"github.com/arduino/go-properties-orderedmap"
 	discovery "github.com/arduino/pluggable-discovery-protocol-handler/v2"
 )
 
@@ -34,6 +37,7 @@ func main() {
 
 // DFUDiscovery is the implementation of the DFU pluggable-discovery
 type DFUDiscovery struct {
+	closeChan chan<- struct{}
 }
 
 // Hello is the handler for the pluggable-discovery HELLO command
@@ -43,10 +47,15 @@ func (d *DFUDiscovery) Hello(userAgent string, protocolVersion int) error {
 
 // Quit is the handler for the pluggable-discovery QUIT command
 func (d *DFUDiscovery) Quit() {
+	d.Stop()
 }
 
 // Stop is the handler for the pluggable-discovery STOP command
 func (d *DFUDiscovery) Stop() error {
+	if d.closeChan != nil {
+		close(d.closeChan)
+		d.closeChan = nil
+	}
 	C.libusbClose()
 	return nil
 }
@@ -56,9 +65,86 @@ func (d *DFUDiscovery) StartSync(eventCB discovery.EventCallback, errorCB discov
 	if cErr := C.libusbOpen(); cErr != nil {
 		return fmt.Errorf("can't open libusb: %s", C.GoString(cErr))
 	}
+	closeChan := make(chan struct{})
+	go func() {
+		for {
+			d.sendUpdates(eventCB, errorCB)
+			select {
+			case <-time.After(5 * time.Second):
+			case <-closeChan:
+				return
+			}
+		}
+	}()
+	d.closeChan = closeChan
 	return nil
 }
 
+func (d *DFUDiscovery) sendUpdates(eventCB discovery.EventCallback, errorCB discovery.ErrorCallback) {
+	C.dfuProbeDevices()
+	for _, dfuIf := range d.getDFUInterfaces() {
+		eventCB("add", dfuIf.AsDiscoveryPort())
+	}
+}
+
 func getPath(dev *C.struct_libusb_device) string {
 	return C.GoString(C.get_path(dev))
 }
+
+// DFUInterface represents a DFU Interface
+type DFUInterface struct {
+	Path         string
+	AltName      string
+	VID, PID     uint16
+	SerialNumber string
+	Flags        uint32
+}
+
+// AsDiscoveryPort converts this DFUInterface into a discovery.Port
+func (i *DFUInterface) AsDiscoveryPort() *discovery.Port {
+	props := properties.NewMap()
+	props.Set("vid", fmt.Sprintf("%04X", i.VID))
+	props.Set("pid", fmt.Sprintf("%04X", i.PID))
+	if i.SerialNumber != "" {
+		props.Set("serial", i.SerialNumber)
+	}
+	// ProtocolLabel: pdfu.flags & DFU_IFF_DFU ? "DFU" : "Runtime"
+	return &discovery.Port{
+		Address:       i.Path,
+		AddressLabel:  i.Path,
+		Protocol:      "dfu",
+		ProtocolLabel: "USB DFU",
+		Properties:    props,
+		HardwareID:    props.Get("serial"),
+	}
+}
+
+func (d *DFUDiscovery) getDFUInterfaces() []*DFUInterface {
+	res := []*DFUInterface{}
+	for pdfu := C.dfu_root; pdfu != nil; pdfu = pdfu.next {
+		fmt.Println(pdfu)
+		if (pdfu.flags & C.DFU_IFF_DFU) == 0 {
+			// decide what to do with DFU runtime objects
+			// for the time being, ignore them
+			continue
+		}
+		ifPath := getPath(pdfu.dev)
+		// for i := 0; i < index; i++ {
+		// 	// allow only one object
+		// 	if j["ports"][i]["address"] == ifPath {
+		// 		index = i
+		// 		break
+		// 	}
+		// }
+
+		dfuIf := &DFUInterface{
+			Path:         ifPath,
+			AltName:      C.GoString(pdfu.alt_name),
+			VID:          uint16(pdfu.vendor),
+			PID:          uint16(pdfu.product),
+			SerialNumber: C.GoString(pdfu.serial_name),
+		}
+		res = append(res, dfuIf)
+	}
+	return res
+}