Use a single exported HidKeyBufferSize from hid_keyboard

Author: IDisposable

internal/hidrpc/message.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 
 	"github.com/google/uuid"
+	"github.com/jetkvm/kvm/internal/usbgadget"
 )
 
 // Message ..
@@ -135,18 +136,16 @@ func (m *Message) KeyboardReport() (KeyboardReport, error) {
 // Macro ..
 type KeyboardMacroStep struct {
 	Modifier byte   // 1 byte
-	Keys     []byte // 6 bytes: HidKeyBufferSize
+	Keys     []byte // 6 bytes: usbgadget.HidKeyBufferSize
 	Delay    uint16 // 2 bytes
 }
+
 type KeyboardMacroReport struct {
 	IsPaste   bool
 	StepCount uint32
 	Steps     []KeyboardMacroStep
 }
 
-// HidKeyBufferSize is the size of the keys buffer in the keyboard report.
-const HidKeyBufferSize int = 6
-
 // KeyboardMacroReport returns the keyboard macro report from the message.
 func (m *Message) KeyboardMacroReport() (KeyboardMacroReport, error) {
 	if m.t != TypeKeyboardMacroReport {
@@ -171,7 +170,7 @@ func (m *Message) KeyboardMacroReport() (KeyboardMacroReport, error) {
 			Delay:    binary.BigEndian.Uint16(m.d[offset+7 : offset+9]),
 		})
 
-		offset += 1 + HidKeyBufferSize + 2
+		offset += 1 + usbgadget.HidKeyBufferSize + 2
 	}
 
 	return KeyboardMacroReport{

internal/usbgadget/hid_keyboard.go

@@ -76,7 +76,7 @@ var keyboardReportDesc = []byte{
 
 const (
 	hidReadBufferSize = 8
-	hidKeyBufferSize  = 6
+	HidKeyBufferSize  = 6
 	hidErrorRollOver  = 0x01
 	// https://www.usb.org/sites/default/files/documents/hid1_11.pdf
 	// https://www.usb.org/sites/default/files/hut1_2.pdf
@@ -342,7 +342,7 @@ func (u *UsbGadget) keyboardWriteHidFile(modifier byte, keys []byte) error {
 		return err
 	}
 
-	_, err := u.writeWithTimeout(u.keyboardHidFile, append([]byte{modifier, 0x00}, keys[:hidKeyBufferSize]...))
+	_, err := u.writeWithTimeout(u.keyboardHidFile, append([]byte{modifier, 0x00}, keys[:HidKeyBufferSize]...))
 	if err != nil {
 		u.logWithSuppression("keyboardWriteHidFile", 100, u.log, err, "failed to write to hidg0")
 		u.keyboardHidFile.Close()
@@ -386,11 +386,11 @@ func (u *UsbGadget) UpdateKeysDown(modifier byte, keys []byte) KeysDownState {
 func (u *UsbGadget) KeyboardReport(modifier byte, keys []byte) error {
 	defer u.resetUserInputTime()
 
-	if len(keys) > hidKeyBufferSize {
-		keys = keys[:hidKeyBufferSize]
+	if len(keys) > HidKeyBufferSize {
+		keys = keys[:HidKeyBufferSize]
 	}
-	if len(keys) < hidKeyBufferSize {
-		keys = append(keys, make([]byte, hidKeyBufferSize-len(keys))...)
+	if len(keys) < HidKeyBufferSize {
+		keys = append(keys, make([]byte, HidKeyBufferSize-len(keys))...)
 	}
 
 	err := u.keyboardWriteHidFile(modifier, keys)
@@ -473,7 +473,7 @@ func (u *UsbGadget) keypressReport(key byte, press bool) (KeysDownState, error)
 		// handle other keys that are not modifier keys by placing or removing them
 		// from the key buffer since the buffer tracks currently pressed keys
 		overrun := true
-		for i := range hidKeyBufferSize {
+		for i := range HidKeyBufferSize {
 			// If we find the key in the buffer the buffer, we either remove it (if press is false)
 			// or do nothing (if down is true) because the buffer tracks currently pressed keys
 			// and if we find a zero byte, we can place the key there (if press is true)
@@ -484,7 +484,7 @@ func (u *UsbGadget) keypressReport(key byte, press bool) (KeysDownState, error)
 					// we are releasing the key, remove it from the buffer
 					if keys[i] != 0 {
 						copy(keys[i:], keys[i+1:])
-						keys[hidKeyBufferSize-1] = 0 // Clear the last byte
+						keys[HidKeyBufferSize-1] = 0 // Clear the last byte
 					}
 				}
 				overrun = false // We found a slot for the key

internal/usbgadget/usbgadget.go

@@ -135,7 +135,7 @@ func newUsbGadget(name string, configMap map[string]gadgetConfigItem, enabledDev
 		keyboardStateCtx:     keyboardCtx,
 		keyboardStateCancel:  keyboardCancel,
 		keyboardState:        0,
-		keysDownState:        KeysDownState{Modifier: 0, Keys: []byte{0, 0, 0, 0, 0, 0}}, // must be initialized to hidKeyBufferSize (6) zero bytes
+		keysDownState:        KeysDownState{Modifier: 0, Keys: []byte{0, 0, 0, 0, 0, 0}}, // must be initialized to usbgadget.HidKeyBufferSize (6) zero bytes
 		kbdAutoReleaseTimers: make(map[byte]*time.Timer),
 		enabledDevices:       *enabledDevices,
 		lastUserInput:        time.Now(),

jsonrpc.go

@@ -1210,7 +1210,7 @@ func executeKeyboardMacro(ctx context.Context, isPaste bool, macro []hidrpc.Keyb
 		case <-ctx.Done():
 			// make sure keyboard state is reset and the client gets notified
 			gadget.ResumeSuspendKeyDownMessages()
-			err := rpcKeyboardReport(0, make([]byte, hidrpc.HidKeyBufferSize))
+			err := rpcKeyboardReport(0, make([]byte, usbgadget.HidKeyBufferSize))
 			if err != nil {
 				logger.Warn().Err(err).Msg("failed to reset keyboard state")
 			}