Force grab/ungrab keyboard+mouse with Right Ctrl key

vncviewer/DesktopWindow.cxx

@@ -78,14 +78,14 @@ static rfb::LogWriter vlog("DesktopWindow");
 // issue for Fl::event_dispatch.
 static std::set<DesktopWindow *> instances;
 
-DesktopWindow::DesktopWindow(int w, int h, const char *name,
+DesktopWindow::DesktopWindow(int w, int h, const char *name_,
                              const rfb::PixelFormat& serverPF,
                              CConn* cc_)
   : Fl_Window(w, h), cc(cc_), offscreen(nullptr), overlay(nullptr),
-    firstUpdate(true),
+    name(nullptr), firstUpdate(true),
     delayedFullscreen(false), sentDesktopSize(false),
     pendingRemoteResize(false), lastResize({0, 0}),
-    keyboardGrabbed(false), mouseGrabbed(false),
+    keyboardGrabbed(false), mouseGrabbed(false), forceGrabbed(false),
     statsLastUpdates(0), statsLastPixels(0), statsLastPosition(0),
     statsGraph(nullptr)
 {
@@ -109,7 +109,7 @@ DesktopWindow::DesktopWindow(int w, int h, const char *name,
 
   callback(handleClose, this);
 
-  setName(name);
+  setName(name_);
 
   OptionsDialog::addCallback(handleOptions, this);
 
@@ -272,6 +272,8 @@ DesktopWindow::~DesktopWindow()
 
   Fl::event_dispatch(Fl::handle_);
 
+  free(name);
+
   // FLTK automatically deletes all child widgets, so we shouldn't touch
   // them ourselves here
 }
@@ -282,53 +284,48 @@ const rfb::PixelFormat &DesktopWindow::getPreferredPF()
   return viewport->getPreferredPF();
 }
 
-
-void DesktopWindow::setName(const char *name)
+void DesktopWindow::setName(const char *new_name)
 {
-  char windowNameStr[100];
-  const char *labelFormat;
-  size_t maxNameSize;
-  char truncatedName[sizeof(windowNameStr)];
-
-  labelFormat = "%s - TigerVNC";
-
-  // Ignore the length of '%s' since it is
-  // a format marker which won't take up space
-  maxNameSize = sizeof(windowNameStr) - 1 - strlen(labelFormat) + 2;
-
-  if (maxNameSize > strlen(name)) {
-    // Guaranteed to fit, no need to truncate
-    strcpy(truncatedName, name);
-  } else if (maxNameSize <= strlen("...")) {
-    // Even an ellipsis won't fit
-    truncatedName[0] = '\0';
-  } else {
-    int offset;
-
-    // We need to truncate, add an ellipsis
-    offset = maxNameSize - strlen("...");
-    strncpy(truncatedName, name, sizeof(truncatedName));
-    strcpy(truncatedName + offset, "...");
+  free(name);
+  name = nullptr;
+  if (new_name) {
+    name = strdup(new_name);
   }
+  updateLabel();
+}
+
+void DesktopWindow::updateLabel() {
+  const char *strTitle = " - TigerVNC";
+  const char *strGrabbed = " [GRAB]";
+  const size_t maxNameLen = 100;
+
+  char *label = (char*)malloc(maxNameLen + strlen(strGrabbed) + strlen(strTitle) + 1);
+  strcpy(label, "");
 
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+  if (name) {
+    if (strlen(name) <= maxNameLen) {
+      strcat(label, name);
+    } else {
+      strncat(label, name, maxNameLen - 3);
+      strcat(label, "...");
+    }
+  } else {
+    strcat(label, "unknown");
+  }
 
-  if (snprintf(windowNameStr, sizeof(windowNameStr), labelFormat,
-               truncatedName) >= (int)sizeof(windowNameStr)) {
-    // This is just to shut up the compiler, as we've already made sure
-    // we won't truncate anything
+  if (keyboardGrabbed || mouseGrabbed) {
+    strcat(label, strGrabbed);
   }
 
-#pragma GCC diagnostic pop
+  strcat(label, strTitle);
 
-  copy_label(windowNameStr);
-}
+  copy_label(label);
 
+  free(label);
+}
 
 // Copy the areas of the framebuffer that have been changed (damaged)
 // to the displayed window.
-
 void DesktopWindow::updateWindow()
 {
   if (firstUpdate) {
@@ -841,6 +838,29 @@ void DesktopWindow::updateOverlay(void *data)
   self->damage(FL_DAMAGE_USER1);
 }
 
+void DesktopWindow::toggleForceGrab() {
+  if (keyboardGrabbed && mouseGrabbed) {
+    ungrabPointer();
+    ungrabKeyboard();
+    forceGrabbed = false;
+  } else {
+    grabPointer();
+    grabKeyboard();
+    forceGrabbed = true;
+  }
+}
+
+bool DesktopWindow::isKeyboardGrabbed() const {
+  return keyboardGrabbed;
+}
+
+bool DesktopWindow::isMouseGrabbed() const {
+  return mouseGrabbed;
+}
+
+bool DesktopWindow::isForceGrabbed() const {
+  return forceGrabbed;
+}
 
 int DesktopWindow::handle(int event)
 {
@@ -877,7 +897,9 @@ int DesktopWindow::handle(int event)
       // We don't get FL_LEAVE with a grabbed pointer, so check manually
       if ((Fl::event_x() < 0) || (Fl::event_x() >= w()) ||
           (Fl::event_y() < 0) || (Fl::event_y() >= h())) {
-        ungrabPointer();
+        if (!forceGrabbed) {
+          ungrabPointer();
+        }
       }
 #if !defined(WIN32) && !defined(__APPLE__)
       Window root, child;
@@ -888,7 +910,9 @@ int DesktopWindow::handle(int event)
       if (XQueryPointer(fl_display, fl_xid(this), &root, &child,
                         &x, &y, &wx, &wy, &mask) &&
           (root != XRootWindow(fl_display, fl_screen))) {
-        ungrabPointer();
+        if (!forceGrabbed) {
+          ungrabPointer();
+        }
       }
 #endif
     }
@@ -1183,6 +1207,7 @@ void DesktopWindow::grabKeyboard()
 #endif
 
   keyboardGrabbed = true;
+  updateLabel();
 
   if (contains(Fl::belowmouse()))
     grabPointer();
@@ -1193,7 +1218,9 @@ void DesktopWindow::ungrabKeyboard()
 {
   Fl::remove_timeout(handleGrab, this);
 
+  forceGrabbed = false;
   keyboardGrabbed = false;
+  updateLabel();
 
   ungrabPointer();
 
@@ -1236,12 +1263,15 @@ void DesktopWindow::grabPointer()
 #endif
 
   mouseGrabbed = true;
+  updateLabel();
 }
 
 
 void DesktopWindow::ungrabPointer()
 {
+  forceGrabbed = false;
   mouseGrabbed = false;
+  updateLabel();
 
 #if !defined(WIN32) && !defined(__APPLE__)
   x11_ungrab_pointer(fl_xid(this));

vncviewer/DesktopWindow.h

@@ -39,7 +39,7 @@ class Fl_Scrollbar;
 class DesktopWindow : public Fl_Window {
 public:
 
-  DesktopWindow(int w, int h, const char *name,
+  DesktopWindow(int w, int h, const char *name_,
                 const rfb::PixelFormat& serverPF, CConn* cc_);
   ~DesktopWindow();
 
@@ -82,6 +82,12 @@ class DesktopWindow : public Fl_Window {
 
   void fullscreen_on();
 
+  void toggleForceGrab();
+
+  bool isKeyboardGrabbed() const;
+  bool isMouseGrabbed() const;
+  bool isForceGrabbed() const;
+
 private:
   static void menuOverlay(void *data);
 
@@ -122,6 +128,8 @@ class DesktopWindow : public Fl_Window {
 
   static void handleStatsTimeout(void *data);
 
+  void updateLabel();
+
 private:
   CConn* cc;
   Fl_Scrollbar *hscroll, *vscroll;
@@ -131,6 +139,8 @@ class DesktopWindow : public Fl_Window {
   unsigned char overlayAlpha;
   struct timeval overlayStart;
 
+  char *name;
+
   bool firstUpdate;
   bool delayedFullscreen;
   bool sentDesktopSize;
@@ -140,6 +150,7 @@ class DesktopWindow : public Fl_Window {
 
   bool keyboardGrabbed;
   bool mouseGrabbed;
+  bool forceGrabbed;
 
   struct statsEntry {
     unsigned ups;

vncviewer/Keyboard.h

@@ -26,7 +26,8 @@ class KeyboardHandler
 public:
   virtual void handleKeyPress(int systemKeyCode,
                               uint32_t keyCode, uint32_t keySym) = 0;
-  virtual void handleKeyRelease(int systemKeyCode) = 0;
+  virtual void handleKeyRelease(int systemKeyCode,
+                                uint32_t keyCode, uint32_t keySym) = 0;
 };
 
 class Keyboard

vncviewer/KeyboardMacOS.mm

@@ -168,9 +168,9 @@
     // We don't get any release events for CapsLock, so we have to
     // send the release right away.
     if (keySym == XK_Caps_Lock)
-      handler->handleKeyRelease(systemKeyCode);
+      handler->handleKeyRelease(systemKeyCode, keyCode, keySym);
   } else {
-    handler->handleKeyRelease(systemKeyCode);
+    handler->handleKeyRelease(systemKeyCode, keyCode, keySym);
   }
 
   return true;

vncviewer/KeyboardWin32.cxx

@@ -292,7 +292,7 @@ bool KeyboardWin32::handleEvent(const void* event)
     case XK_Katakana:
     case XK_Hiragana:
     case XK_Romaji:
-      handler->handleKeyRelease(systemKeyCode);
+      handler->handleKeyRelease(systemKeyCode, keyCode, keySym);
     }
 
     // Shift key tracking, see below
@@ -335,7 +335,7 @@ bool KeyboardWin32::handleEvent(const void* event)
 
     keyCode = translateSystemKeyCode(systemKeyCode);
 
-    handler->handleKeyRelease(keyCode);
+    handler->handleKeyRelease(keyCode, keyCode, keySym);
 
     // Windows has a rather nasty bug where it won't send key release
     // events for a Shift button if the other Shift is still pressed

vncviewer/KeyboardX11.cxx

@@ -92,7 +92,7 @@ bool KeyboardX11::handleEvent(const void* event)
 
   assert(event);
 
-  if (xevent->type == KeyPress) {
+  if (xevent->type == KeyPress || xevent->type == KeyRelease) {
     int keycode;
     char str;
     KeySym keysym;
@@ -105,10 +105,11 @@ bool KeyboardX11::handleEvent(const void* event)
                  (int)xevent->xkey.keycode);
     }
 
-    handler->handleKeyPress(xevent->xkey.keycode, keycode, keysym);
-    return true;
-  } else if (xevent->type == KeyRelease) {
-    handler->handleKeyRelease(xevent->xkey.keycode);
+    if (xevent->type == KeyPress) {
+      handler->handleKeyPress(xevent->xkey.keycode, keycode, keysym);
+    } else if (xevent->type == KeyRelease) {
+      handler->handleKeyRelease(xevent->xkey.keycode, keycode, keysym);
+    }
     return true;
   }