From 0e344c983034adb3d2cd2756748c9d2829545463 Mon Sep 17 00:00:00 2001
From: Christian Prochaska <christian.prochaska@genode-labs.com>
Date: Thu, 26 Mar 2015 15:02:05 +0100
Subject: [PATCH] vbox: support more mouse event combinations

VirtualBox can receive absolute or relative mouse motion events from the
'Input' service and the VM can support either or both of them. With this
patch, more of the possible combinations are handled.

Fixes #1470
---
 repos/ports/src/virtualbox/frontend/console.h | 49 ++++++++++++++++---
 1 file changed, 42 insertions(+), 7 deletions(-)

diff --git a/repos/ports/src/virtualbox/frontend/console.h b/repos/ports/src/virtualbox/frontend/console.h
index d648032f6..d57925f99 100644
--- a/repos/ports/src/virtualbox/frontend/console.h
+++ b/repos/ports/src/virtualbox/frontend/console.h
@@ -109,6 +109,7 @@ class GenodeConsole : public Console {
 		Genode::Signal_context   _context;
 		Input::Event            *_ev_buf;
 		unsigned                 _ax, _ay;
+		bool                     _last_received_motion_event_was_absolute;
 
 		bool _key_status[Input::KEY_MAX + 1];
 
@@ -125,7 +126,8 @@ class GenodeConsole : public Console {
 		:
 			Console(),
 			_ev_buf(static_cast<Input::Event *>(Genode::env()->rm_session()->attach(_input.dataspace()))),
-			_ax(0), _ay(0)
+			_ax(0), _ay(0),
+			_last_received_motion_event_was_absolute(false)
 		{
 			for (unsigned i = 0; i <= Input::KEY_MAX; i++)
 				_key_status[i] = 0;
@@ -191,22 +193,55 @@ class GenodeConsole : public Console {
 					                       | (_key_status[Input::BTN_RIGHT]  ? MouseButtonState_RightButton : 0)
 					                       | (_key_status[Input::BTN_MIDDLE] ? MouseButtonState_MiddleButton : 0);
 					if (ev.is_absolute_motion()) {
+
+						_last_received_motion_event_was_absolute = true;
+
 						/* transform absolute to relative if guest is so odd */
 						if (!guest_abs && guest_rel) {
 							int const boundary = 20;
-							int rx = ev.ax() - _ax; _ax = ev.ax();
-							int ry = ev.ay() - _ay; _ay = ev.ay();
+							int rx = ev.ax() - _ax;
+							int ry = ev.ay() - _ay;
 							rx = Genode::min(boundary, Genode::max(-boundary, rx));
 							ry = Genode::min(boundary, Genode::max(-boundary, ry));
 							gMouse->PutMouseEvent(rx, ry, 0, 0, buttons);
 						} else
 							gMouse->PutMouseEventAbsolute(ev.ax(), ev.ay(), 0,
 							                              0, buttons);
-					} else if (ev.is_relative_motion())
-						gMouse->PutMouseEvent(ev.rx(), ev.ry(), 0, 0, buttons);
+
+						_ax = ev.ax();
+						_ay = ev.ay();
+
+					} else if (ev.is_relative_motion()) {
+
+						_last_received_motion_event_was_absolute = false;
+
+						/* prefer relative motion event */
+						if (guest_rel)
+							gMouse->PutMouseEvent(ev.rx(), ev.ry(), 0, 0, buttons);
+						else if (guest_abs) {
+							_ax += ev.rx();
+							_ay += ev.ry();
+							gMouse->PutMouseEventAbsolute(_ax, _ay, 0, 0, buttons);
+						}
+					}
 					/* only the buttons changed */
-					else
-						gMouse->PutMouseEvent(0, 0, 0, 0, buttons);
+					else {
+
+						if (_last_received_motion_event_was_absolute) {
+							/* prefer absolute button event */
+							if (guest_abs)
+								gMouse->PutMouseEventAbsolute(_ax, _ay, 0, 0, buttons);
+							else if (guest_rel)
+								gMouse->PutMouseEvent(0, 0, 0, 0, buttons);
+						} else {
+							/* prefer relative button event */
+							if (guest_rel)
+								gMouse->PutMouseEvent(0, 0, 0, 0, buttons);
+							else if (guest_abs)
+								gMouse->PutMouseEventAbsolute(_ax, _ay, 0, 0, buttons);
+						}
+
+					}
 				}
 
 				if (is_wheel)