Add support for setting vendor/device IDs (#10)

Sets vendor and product IDs, defaults to the prior default values.
This is needed for some games to be able to correctly identify the virtual devices since not all games support device indexes.

Reviewed-on: https://codeberg.org/annabunches/joyful/pulls/10

internal/virtualdevice/init.go

@@ -7,8 +7,20 @@ import (
 	"git.annabunches.net/annabunches/joyful/internal/eventcodes"
 	"git.annabunches.net/annabunches/joyful/internal/logger"
 	"github.com/holoplot/go-evdev"
+	"strconv"
 )
 
+func ParseUInt16(s string, def uint16) uint16 {
+    if s == "" {
+        return def
+    }
+    v, err := strconv.ParseUint(s, 0, 16)
+    if err != nil {
+        return def
+    }
+    return uint16(v)
+}
+
 // NewEventBuffer takes a virtual device config specification, creates the underlying
 // evdev.InputDevice, and wraps it in a buffered event emitter.
 func NewEventBuffer(config configparser.DeviceConfigVirtual) (*EventBuffer, error) {
@@ -38,11 +50,11 @@ func NewEventBuffer(config configparser.DeviceConfigVirtual) (*EventBuffer, erro
 
 	device, err := evdev.CreateDevice(
 		name,
-		// TODO: placeholders. Who knows what these should actually be...
+		// TODO: placeholders. BusType = differentiate between input bus (3 = usb), Vendor = uint16 vendor id, Product: uint16 devoce id, Version = device version (differentiate between differing versions of exact same device)
 		evdev.InputID{
 			BusType: 0x03,
-			Vendor:  0x4711,
-			Product: 0x0816,
+			Vendor:  ParseUInt16(config.VendorId, VirtualDeviceVendorId),
+			Product: ParseUInt16(config.DeviceId, VirtualDeviceDeviceId),
 			Version: 1,
 		},
 		capabilities,

internal/virtualdevice/variables.go

@@ -7,7 +7,9 @@ const (
 	DevicePresetGamepad  = "gamepad"
 	DevicePresetJoystick = "joystick"
 	DevicePresetMouse    = "mouse"
-
+	
+	VirtualDeviceVendorId = 0x4711
+	VirtualDeviceDeviceId = 0x0816
 	VirtualDeviceMaxButtons = 74
 )