Better detection of AltGr on Windows
Try to properly detect the fake CtrlL+AltR sequence Windows sends
when pressing AltGr. This allows us to send more accurate key
events over to the server.
diff --git a/vncviewer/Viewport.cxx b/vncviewer/Viewport.cxx
index 7af19aa..ba0b0e9 100644
--- a/vncviewer/Viewport.cxx
+++ b/vncviewer/Viewport.cxx
@@ -115,6 +115,9 @@
Viewport::Viewport(int w, int h, const rfb::PixelFormat& serverPF, CConn* cc_)
: Fl_Widget(0, 0, w, h), cc(cc_), frameBuffer(NULL),
lastPointerPos(0, 0), lastButtonMask(0),
+#ifdef WIN32
+ altGrArmed(false),
+#endif
menuCtrlKey(false), menuAltKey(false), cursor(NULL)
{
#if !defined(WIN32) && !defined(__APPLE__)
@@ -187,6 +190,9 @@
// Unregister all timeouts in case they get a change tro trigger
// again later when this object is already gone.
Fl::remove_timeout(handlePointerTimeout, this);
+#ifdef WIN32
+ Fl::remove_timeout(handleAltGrTimeout, this);
+#endif
Fl::remove_system_handler(handleSystemEvent);
@@ -734,26 +740,6 @@
}
#endif
-#ifdef WIN32
- // Ugly hack alert!
- //
- // Windows doesn't have a proper AltGr, but handles it using fake
- // Ctrl+Alt. Unfortunately X11 doesn't generally like the combination
- // Ctrl+Alt+AltGr, which we usually end up with when Xvnc tries to
- // get everything in the correct state. Cheat and temporarily release
- // Ctrl and Alt when we send some other symbol.
- if (downKeySym.count(0x1d) && downKeySym.count(0xb8)) {
- vlog.debug("Faking release of AltGr (Ctrl_L+Alt_R)");
- try {
- cc->writer()->keyEvent(downKeySym[0x1d], 0x1d, false);
- cc->writer()->keyEvent(downKeySym[0xb8], 0xb8, false);
- } catch (rdr::Exception& e) {
- vlog.error("%s", e.str());
- exit_vncviewer(e.str());
- }
- }
-#endif
-
// Because of the way keyboards work, we cannot expect to have the same
// symbol on release as when pressed. This breaks the VNC protocol however,
// so we need to keep track of what keysym a key _code_ generated on press
@@ -777,20 +763,6 @@
vlog.error("%s", e.str());
exit_vncviewer(e.str());
}
-
-#ifdef WIN32
- // Ugly hack continued...
- if (downKeySym.count(0x1d) && downKeySym.count(0xb8)) {
- vlog.debug("Restoring AltGr state");
- try {
- cc->writer()->keyEvent(downKeySym[0x1d], 0x1d, true);
- cc->writer()->keyEvent(downKeySym[0xb8], 0xb8, true);
- } catch (rdr::Exception& e) {
- vlog.error("%s", e.str());
- exit_vncviewer(e.str());
- }
- }
-#endif
}
@@ -862,6 +834,30 @@
keyCode = ((msg->lParam >> 16) & 0xff);
+ // Windows doesn't have a proper AltGr, but handles it using fake
+ // Ctrl+Alt. However the remote end might not be Windows, so we need
+ // to merge those in to a single AltGr event. We detect this case
+ // by seeing the two key events directly after each other with a very
+ // short time between them (<50ms).
+ if (self->altGrArmed) {
+ self->altGrArmed = false;
+ Fl::remove_timeout(handleAltGrTimeout);
+
+ if (isExtended && (keyCode == 0x38) && (vKey == VK_MENU) &&
+ ((msg->time - self->altGrCtrlTime) < 50)) {
+ // FIXME: We fail to detect this if either Ctrl key is
+ // first manually pressed as Windows then no longer
+ // sends the fake Ctrl down event. It does however
+ // happily send real Ctrl events even when AltGr
+ // is already down.
+ vlog.debug("Detected AltGr combination");
+ self->handleKeyPress(0xb8, XK_ISO_Level3_Shift);
+ return 1;
+ }
+
+ self->handleKeyPress(0x1d, XK_Control_L);
+ }
+
if (keyCode == SCAN_FAKE) {
vlog.debug("Ignoring fake key press (virtual key 0x%02x)", vKey);
return 1;
@@ -921,6 +917,14 @@
if ((keySym == XK_Shift_L) && (keyCode == 0x36))
keySym = XK_Shift_R;
+ // Possible start of AltGr sequence? (see above)
+ if ((keyCode == 0x1d) && (keySym == XK_Control_L)) {
+ self->altGrArmed = true;
+ self->altGrCtrlTime = msg->time;
+ Fl::add_timeout(0.1, handleAltGrTimeout, self);
+ return 1;
+ }
+
self->handleKeyPress(keyCode, keySym);
return 1;
@@ -934,6 +938,14 @@
keyCode = ((msg->lParam >> 16) & 0xff);
+ // We can't get a release in the middle of an AltGr sequence, so
+ // abort that detection
+ if (self->altGrArmed) {
+ self->altGrArmed = false;
+ Fl::remove_timeout(handleAltGrTimeout);
+ self->handleKeyPress(0x1d, XK_Control_L);
+ }
+
if (keyCode == SCAN_FAKE) {
vlog.debug("Ignoring fake key release (virtual key 0x%02x)", vKey);
return 1;
@@ -1046,6 +1058,18 @@
return 0;
}
+#ifdef WIN32
+void Viewport::handleAltGrTimeout(void *data)
+{
+ Viewport *self = (Viewport *)data;
+
+ assert(self);
+
+ self->altGrArmed = false;
+ self->handleKeyPress(0x1d, XK_Control_L);
+}
+#endif
+
void Viewport::initContextMenu()
{
contextMenu->clear();
diff --git a/vncviewer/Viewport.h b/vncviewer/Viewport.h
index a4b7d8b..3895fc7 100644
--- a/vncviewer/Viewport.h
+++ b/vncviewer/Viewport.h
@@ -76,6 +76,10 @@
static int handleSystemEvent(void *event, void *data);
+#ifdef WIN32
+ static void handleAltGrTimeout(void *data);
+#endif
+
void initContextMenu();
void popupContextMenu();
@@ -94,6 +98,11 @@
typedef std::map<int, rdr::U32> DownMap;
DownMap downKeySym;
+#ifdef WIN32
+ bool altGrArmed;
+ unsigned int altGrCtrlTime;
+#endif
+
rdr::U32 menuKeySym;
int menuKeyCode, menuKeyFLTK;
Fl_Menu_Button *contextMenu;