vbox5: react on host size changes immediately

The guest may take some time to adjust nevertheless.

Fixes #3498

repos/ports/run/virtualbox.run

@@ -278,7 +278,7 @@ lappend_if [expr         $use_top] boot_modules top
 lappend_if [expr         $use_gui] boot_modules report_rom
 
 append boot_modules {
-	ld.lib.so libc.lib.so vfs.lib.so libm.lib.so libc_pipe.lib.so
+	libc.lib.so vfs.lib.so libm.lib.so libc_pipe.lib.so
 	libiconv.lib.so stdcxx.lib.so
 	qemu-usb.lib.so
 }

repos/ports/src/virtualbox5/frontend/fb.h

@@ -37,12 +37,7 @@ class Genodefb :
 		Nitpicker::Connection &_nitpicker;
 		Fb_Genode::Session    &_fb;
 		View_handle            _view;
-
+		Fb_Genode::Mode        _fb_mode { 1024, 768, Fb_Genode::Mode::RGB565 };
-		/* The mode at the time when the mode change signal was received */
-		Fb_Genode::Mode        _next_fb_mode { 1024, 768, Fb_Genode::Mode::RGB565 };
-
-		/* The mode matching the currently attached dataspace */
-		Fb_Genode::Mode        _fb_mode;
 
 		/*
 		 * The mode currently used by the VM. Can be smaller than the
@@ -55,20 +50,21 @@ class Genodefb :
 
 		void _clear_screen()
 		{
-			size_t const num_pixels = _fb_mode.width() * _virtual_fb_mode.height();
+			size_t const max_h = Genode::min(_fb_mode.height(), _virtual_fb_mode.height());
+			size_t const num_pixels = _fb_mode.width() * max_h;
 			memset(_fb_base, 0, num_pixels * _fb_mode.bytes_per_pixel());
 			_fb.refresh(0, 0, _virtual_fb_mode.width(), _virtual_fb_mode.height());
 		}
 
 		void _adjust_buffer()
 		{
-			_nitpicker.buffer(Fb_Genode::Mode(_next_fb_mode.width(), _next_fb_mode.height(),
+			_nitpicker.buffer(Fb_Genode::Mode(_fb_mode.width(), _fb_mode.height(),
 			                                  Fb_Genode::Mode::RGB565), false);
 
 			typedef Nitpicker::Session::Command Command;
 
 			Nitpicker::Rect rect(Nitpicker::Point(0, 0),
-			                     Nitpicker::Area(_next_fb_mode.width(), _next_fb_mode.height()));
+			                     Nitpicker::Area(_fb_mode.width(), _fb_mode.height()));
 
 			_nitpicker.enqueue<Command::Geometry>(_view, rect);
 			_nitpicker.execute();
@@ -85,7 +81,7 @@ class Genodefb :
 			_nitpicker.enqueue<Command::To_front>(_view, View_handle());
 			_nitpicker.execute();
 
-			return _next_fb_mode;
+			return _fb_mode;
 		}
 
 	public:
@@ -95,22 +91,28 @@ class Genodefb :
 			_env(env),
 			_nitpicker(nitpicker),
 			_fb(*nitpicker.framebuffer()),
-			_fb_mode(_initial_setup()),
+			_virtual_fb_mode(_initial_setup()),
-			_virtual_fb_mode(_fb_mode),
 			_fb_base(env.rm().attach(_fb.dataspace()))
 		{
 			int rc = RTCritSectInit(&_fb_lock);
 			Assert(rc == VINF_SUCCESS);
 		}
 
-		/* Return the next mode of the framebuffer */ 
+		int w() const { return _fb_mode.width(); }
-		int w() const { return _next_fb_mode.width(); }
+		int h() const { return _fb_mode.height(); }
-		int h() const { return _next_fb_mode.height(); }
 
 		void update_mode(Fb_Genode::Mode mode)
 		{
 			Lock();
-			_next_fb_mode = mode;
+
+			_fb_mode = mode;
+
+			_env.rm().detach(_fb_base);
+
+			_adjust_buffer();
+
+			_fb_base = _env.rm().attach(_fb.dataspace());
+
 			Unlock();
 		}
 
@@ -131,42 +133,33 @@ class Genodefb :
 
 			Lock();
 
-			bool ok = (w <= (ULONG)_next_fb_mode.width()) &&
+			bool ok = (w <= (ULONG)_fb_mode.width()) &&
-			          (h <= (ULONG)_next_fb_mode.height());
+			          (h <= (ULONG)_fb_mode.height());
 
 			if (ok) {
 				Genode::log("fb resize : [", screen, "] ",
 				            _virtual_fb_mode.width(), "x",
 				            _virtual_fb_mode.height(), " -> ",
 				            w, "x", h,
-				            " (host: ", _next_fb_mode.width(), "x",
+				            " (host: ", _fb_mode.width(), "x",
-				             _next_fb_mode.height(), ")");
+				             _fb_mode.height(), ")");
 
-				if ((w < (ULONG)_next_fb_mode.width()) ||
+				if ((w < (ULONG)_fb_mode.width()) ||
-				    (h < (ULONG)_next_fb_mode.height())) {
+				    (h < (ULONG)_fb_mode.height())) {
 					/* clear the old content around the new, smaller area. */
 				    _clear_screen();
 				}
 
-				_fb_mode = _next_fb_mode;
-
 				_virtual_fb_mode = Fb_Genode::Mode(w, h, Fb_Genode::Mode::RGB565);
 
-				_env.rm().detach(_fb_base);
-
-				_adjust_buffer();
-
-				_fb_base = _env.rm().attach(_fb.dataspace());
-
 				result = S_OK;
-
 			} else
 				Genode::log("fb resize : [", screen, "] ",
 				            _virtual_fb_mode.width(), "x",
 				            _virtual_fb_mode.height(), " -> ",
 				            w, "x", h, " ignored"
-				            " (host: ", _next_fb_mode.width(), "x",
+				            " (host: ", _fb_mode.width(), "x",
-				             _next_fb_mode.height(), ")");
+				             _fb_mode.height(), ")");
 
 			Unlock();
 
@@ -201,9 +194,11 @@ class Genodefb :
 		                               PRUint32 imageSize,
 		                               PRUint8 *image) override
 		{
-			Nitpicker::Area area_fb = Nitpicker::Area(_fb_mode.width(),
+			Lock();
-			                                          _fb_mode.height());
+
-			Nitpicker::Area area_vm = Nitpicker::Area(width, height);
+			Nitpicker::Area const area_fb = Nitpicker::Area(_fb_mode.width(),
+			                                                _fb_mode.height());
+			Nitpicker::Area const area_vm = Nitpicker::Area(width, height);
 
 			using namespace Genode;
 
@@ -217,6 +212,8 @@ class Genodefb :
 
 			_fb.refresh(o_x, o_y, area_vm.w(), area_vm.h());
 
+			Unlock();
+
 			return S_OK;
 		}
 
@@ -234,8 +231,8 @@ class Genodefb :
 			if (!supported)
 				return E_POINTER;
 
-			*supported = ((width <= (ULONG)_next_fb_mode.width()) &&
+			*supported = ((width <= (ULONG)_fb_mode.width()) &&
-			              (height <= (ULONG)_next_fb_mode.height()));
+			              (height <= (ULONG)_fb_mode.height()));
 
 			return S_OK;
 		}