rfb_win32: Use scan codes if available

If scan codes are available using QEMU Extended Keyboard Messages
from clients, use that to inject scancodes directly into the
system using the SendInput API.

No conversion is needed as Windows uses the same scancode encoding.

Signed-off-by: Rahul Kale <Rahul.Kale@barco.com>
Signed-off-by: Peter Korsgaard <peter.korsgaard@barco.com>

win/rfb_win32/SInput.cxx

@@ -134,6 +134,9 @@ win32::SPointer::pointerEvent(const Point& pos, int buttonmask)
 BoolParameter rfb::win32::SKeyboard::deadKeyAware("DeadKeyAware",
   "Whether to assume the viewer has already interpreted dead key sequences "
   "into latin-1 characters", true);
+BoolParameter rfb::win32::SKeyboard::rawKeyboard("RawKeyboard",
+  "Send keyboard events straight through and avoid mapping them to the "
+  "current keyboard layout", false);
 
 // The keysymToAscii table transforms a couple of awkward keysyms into their
 // ASCII equivalents.
@@ -229,6 +232,31 @@ inline void doKeyboardEvent(BYTE vkCode, DWORD flags) {
   keybd_event(vkCode, MapVirtualKey(vkCode, 0), flags, 0);
 }
 
+inline void doScanCodeEvent(BYTE scancode, bool down) {
+  INPUT evt;
+
+  evt.type = INPUT_KEYBOARD;
+  evt.ki.wVk = 0;
+  evt.ki.dwFlags = KEYEVENTF_SCANCODE;
+
+  if (!down)
+    evt.ki.dwFlags |= KEYEVENTF_KEYUP;
+
+  if (scancode & 0x80) {
+    evt.ki.dwFlags |= KEYEVENTF_EXTENDEDKEY;
+    scancode &= ~0x80;
+  }
+
+  evt.ki.wScan = scancode;
+  evt.ki.dwExtraInfo = 0;
+  evt.ki.time = 0;
+  vlog.debug("SendInput ScanCode: 0x%x Flags: 0x%lx %s", scancode,
+             evt.ki.dwFlags, down ? "Down" : "Up");
+
+  if (SendInput(1, &evt, sizeof(evt)) != 1)
+    vlog.error("SendInput %lu", GetLastError());
+}
+
 // KeyStateModifier is a class which helps simplify generating a "fake" press
 // or release of shift, ctrl, alt, etc.  An instance of the class is created
 // for every key which may need to be pressed or released.  Then either press()
@@ -323,6 +351,13 @@ win32::SKeyboard::SKeyboard()
 
 void win32::SKeyboard::keyEvent(rdr::U32 keysym, rdr::U32 keycode, bool down)
 {
+  // If scan code is available use that directly as windows uses
+  // compatible scancodes
+  if (keycode && rawKeyboard) {
+    doScanCodeEvent(keycode, down);
+    return;
+  }
+
   for (unsigned int i = 0; i < sizeof(keysymToAscii) / sizeof(keysymToAscii_t); i++) {
     if (keysymToAscii[i].keysym == keysym) {
       keysym = keysymToAscii[i].ascii;

win/rfb_win32/SInput.h

@@ -55,6 +55,7 @@ namespace rfb {
       SKeyboard();
       void keyEvent(rdr::U32 keysym, rdr::U32 keycode, bool down);
       static BoolParameter deadKeyAware;
+      static BoolParameter rawKeyboard;
     private:
       std::map<rdr::U32,rdr::U8> vkMap;
       std::map<rdr::U32,bool> extendedMap;

win/vncconfig/Inputs.h

@@ -37,6 +37,7 @@ namespace rfb {
           regKey(rk), enableAffectSSaver(true) {}
       void initDialog() {
         setItemChecked(IDC_ACCEPT_KEYS, rfb::Server::acceptKeyEvents);
+        setItemChecked(IDC_RAW_KEYBOARD, SKeyboard::rawKeyboard);
         setItemChecked(IDC_ACCEPT_PTR, rfb::Server::acceptPointerEvents);
         setItemChecked(IDC_ACCEPT_CUTTEXT, rfb::Server::acceptCutText);
         setItemChecked(IDC_SEND_CUTTEXT, rfb::Server::sendCutText);
@@ -52,6 +53,7 @@ namespace rfb {
         BOOL inputResetsBlocked;
         SystemParametersInfo(SPI_GETBLOCKSENDINPUTRESETS, 0, &inputResetsBlocked, 0);
         setChanged((rfb::Server::acceptKeyEvents != isItemChecked(IDC_ACCEPT_KEYS)) ||
+          (SKeyboard::rawKeyboard != isItemChecked(IDC_RAW_KEYBOARD)) ||
           (rfb::Server::acceptPointerEvents != isItemChecked(IDC_ACCEPT_PTR)) ||
           (rfb::Server::acceptCutText != isItemChecked(IDC_ACCEPT_CUTTEXT)) ||
           (rfb::Server::sendCutText != isItemChecked(IDC_SEND_CUTTEXT)) ||
@@ -61,6 +63,7 @@ namespace rfb {
       }
       bool onOk() {
         regKey.setBool(_T("AcceptKeyEvents"), isItemChecked(IDC_ACCEPT_KEYS));
+        regKey.setBool(_T("RawKeyboard"), isItemChecked(IDC_RAW_KEYBOARD));
         regKey.setBool(_T("AcceptPointerEvents"), isItemChecked(IDC_ACCEPT_PTR));
         regKey.setBool(_T("AcceptCutText"), isItemChecked(IDC_ACCEPT_CUTTEXT));
         regKey.setBool(_T("SendCutText"), isItemChecked(IDC_SEND_CUTTEXT));

win/vncconfig/resource.h

@@ -77,6 +77,7 @@
 #define IDC_RFB_ENABLE                  1082
 #define IDC_LOAD_CERT                   1087
 #define IDC_LOAD_CERTKEY                1088
+#define IDC_RAW_KEYBOARD                1089
 #define ID_OPTIONS                      40001
 #define ID_CLOSE                        40002
 #define ID_ABOUT                        40003

win/vncconfig/vncconfig.rc

@@ -206,17 +206,19 @@ BEGIN
                     "Button",BS_AUTOCHECKBOX | WS_TABSTOP,7,10,172,15
     CONTROL         "Accept keyboard events from clients",IDC_ACCEPT_KEYS,
                     "Button",BS_AUTOCHECKBOX | WS_TABSTOP,7,25,172,15
+    CONTROL         "Send raw keyboard events to applications",IDC_RAW_KEYBOARD,
+                    "Button",BS_AUTOCHECKBOX | WS_TABSTOP,7,40,172,15
     CONTROL         "Accept clipboard updates from clients",
                     IDC_ACCEPT_CUTTEXT,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,
-                    7,40,172,15
+                    7,55,172,15
     CONTROL         "Send clipboard updates to clients",IDC_SEND_CUTTEXT,
-                    "Button",BS_AUTOCHECKBOX | WS_TABSTOP,7,55,172,15
+                    "Button",BS_AUTOCHECKBOX | WS_TABSTOP,7,70,172,15
     CONTROL         "Allow input events to affect the screen-saver",
                     IDC_AFFECT_SCREENSAVER,"Button",BS_AUTOCHECKBOX | 
-                    WS_TABSTOP,7,70,172,15
+                    WS_TABSTOP,7,85,172,15
     CONTROL         "Disable local inputs while server is in use",
                     IDC_DISABLE_LOCAL_INPUTS,"Button",BS_AUTOCHECKBOX | 
-                    WS_TABSTOP,7,95,172,15
+                    WS_TABSTOP,7,110,172,15
 END
 
 IDD_ABOUT DIALOG DISCARDABLE  0, 0, 300, 92