kvm/usb.go

package kvm

import (
	"os"
	"time"

	"kvm/internal/usbgadget"
)

var gadget *usbgadget.UsbGadget

// initUsbGadget initializes the USB gadget.
// call it only after the config is loaded.
func initUsbGadget() {
	gadget = usbgadget.NewUsbGadget(
		"kvm",
		config.UsbDevices,
		config.UsbConfig,
		usbLogger,
	)

	go func() {
		for {
			checkUSBState()
			time.Sleep(500 * time.Millisecond)
		}
	}()

	gadget.SetOnKeyboardStateChange(func(state usbgadget.KeyboardState) {
		if currentSession != nil {
			writeJSONRPCEvent("keyboardLedState", state, currentSession)
		}
	})

	// open the keyboard hid file to listen for keyboard events
	if err := gadget.OpenKeyboardHidFile(); err != nil {
		usbLogger.Error().Err(err).Msg("failed to open keyboard hid file")
	}
}

func rpcKeyboardReport(modifier uint8, keys []uint8) error {
	return gadget.KeyboardReport(modifier, keys)
}

func rpcAbsMouseReport(x, y int, buttons uint8) error {
	return gadget.AbsMouseReport(x, y, buttons)
}

func rpcRelMouseReport(dx, dy int8, buttons uint8) error {
	return gadget.RelMouseReport(dx, dy, buttons)
}

func rpcWheelReport(wheelY int8) error {
	return gadget.AbsMouseWheelReport(wheelY)
}

func rpcGetKeyboardLedState() (state usbgadget.KeyboardState) {
	return gadget.GetKeyboardState()
}

var usbState = "unknown"

func rpcGetUSBState() (state string) {
	return gadget.GetUsbState()
}

func triggerUSBStateUpdate() {
	go func() {
		if currentSession == nil {
			usbLogger.Info().Msg("No active RPC session, skipping update state update")
			return
		}
		writeJSONRPCEvent("usbState", usbState, currentSession)
	}()
}

func checkUSBState() {
	newState := gadget.GetUsbState()
	if newState == usbState {
		return
	}
	usbState = newState

	usbLogger.Info().Str("from", usbState).Str("to", newState).Msg("USB state changed")
	requestDisplayUpdate(true)
	triggerUSBStateUpdate()
}

func rpcSendUsbWakeupSignal() error {
	err := os.WriteFile("/sys/class/udc/ffb00000.usb/srp", []byte("1"), 0644)
	if err != nil {
		return err
	}
	return nil
}