5 files changed, 26 insertions, 9 deletions
diff --git a/unix/x0vncserver/XDesktop.cxx b/unix/x0vncserver/XDesktop.cxx
index 29af059f..bf796452 100644
--- a/unix/x0vncserver/XDesktop.cxx
+++ b/unix/x0vncserver/XDesktop.cxx
@@ -242,9 +242,9 @@ void XDesktop::init(VNCServer* vs)
 void XDesktop::start()
 {
   // Determine actual number of buttons of the X pointer device.
-  unsigned char btnMap[8];
-  int numButtons = XGetPointerMapping(dpy, btnMap, 8);
-  maxButtons = (numButtons > 8) ? 8 : numButtons;
+  unsigned char btnMap[9];
+  int numButtons = XGetPointerMapping(dpy, btnMap, 9);
+  maxButtons = (numButtons > 9) ? 9 : numButtons;
   vlog.info("Enabling %d button%s of X pointer device",
             maxButtons, (maxButtons != 1) ? "s" : "");
 
@@ -342,7 +342,7 @@ void XDesktop::queryConnection(network::Socket* sock,
   queryConnectDialog->map();
 }
 
-void XDesktop::pointerEvent(const Point& pos, uint8_t buttonMask) {
+void XDesktop::pointerEvent(const Point& pos, uint16_t buttonMask) {
 #ifdef HAVE_XTEST
   if (!haveXtest) return;
   XTestFakeMotionEvent(dpy, DefaultScreen(dpy),
diff --git a/unix/x0vncserver/XDesktop.h b/unix/x0vncserver/XDesktop.h
index cf374fb9..711d6893 100644
--- a/unix/x0vncserver/XDesktop.h
+++ b/unix/x0vncserver/XDesktop.h
@@ -60,7 +60,7 @@ public:
   bool isRunning();
   void queryConnection(network::Socket* sock,
                        const char* userName) override;
-  void pointerEvent(const rfb::Point& pos, uint8_t buttonMask) override;
+  void pointerEvent(const rfb::Point& pos, uint16_t buttonMask) override;
   void keyEvent(uint32_t keysym, uint32_t xtcode, bool down) override;
   unsigned int setScreenLayout(int fb_width, int fb_height,
                                const rfb::ScreenSet& layout) override;
@@ -79,7 +79,7 @@ protected:
   rfb::VNCServer* server;
   QueryConnectDialog* queryConnectDialog;
   network::Socket* queryConnectSock;
-  uint8_t oldButtonMask;
+  uint16_t oldButtonMask;
   bool haveXtest;
   bool haveDamage;
   int maxButtons;
diff --git a/unix/xserver/hw/vnc/XserverDesktop.cc b/unix/xserver/hw/vnc/XserverDesktop.cc
index e3bc57d8..328b0886 100644
--- a/unix/xserver/hw/vnc/XserverDesktop.cc
+++ b/unix/xserver/hw/vnc/XserverDesktop.cc
@@ -463,7 +463,7 @@ void XserverDesktop::terminate()
   kill(getpid(), SIGTERM);
 }
 
-void XserverDesktop::pointerEvent(const Point& pos, uint8_t buttonMask)
+void XserverDesktop::pointerEvent(const Point& pos, uint16_t buttonMask)
 {
   vncPointerMove(pos.x + vncGetScreenX(screenIndex),
                  pos.y + vncGetScreenY(screenIndex));
diff --git a/unix/xserver/hw/vnc/XserverDesktop.h b/unix/xserver/hw/vnc/XserverDesktop.h
index d287b72f..8c543db7 100644
--- a/unix/xserver/hw/vnc/XserverDesktop.h
+++ b/unix/xserver/hw/vnc/XserverDesktop.h
@@ -95,7 +95,7 @@ public:
   void terminate() override;
   void queryConnection(network::Socket* sock,
                        const char* userName) override;
-  void pointerEvent(const rfb::Point& pos, uint8_t buttonMask) override;
+  void pointerEvent(const rfb::Point& pos, uint16_t buttonMask) override;
   void keyEvent(uint32_t keysym, uint32_t keycode, bool down) override;
   unsigned int setScreenLayout(int fb_width, int fb_height,
                                const rfb::ScreenSet& layout) override;
diff --git a/unix/xserver/hw/vnc/vncInput.c b/unix/xserver/hw/vnc/vncInput.c
index 1de41430..a705a85a 100644
--- a/unix/xserver/hw/vnc/vncInput.c
+++ b/unix/xserver/hw/vnc/vncInput.c
@@ -50,7 +50,7 @@ extern const unsigned int code_map_qnum_to_xorgevdev_len;
 extern const unsigned short code_map_qnum_to_xorgkbd[];
 extern const unsigned int code_map_qnum_to_xorgkbd_len;
 
-#define BUTTONS 7
+#define BUTTONS 9
 
 DeviceIntPtr vncKeyboardDev;
 DeviceIntPtr vncPointerDev;
@@ -207,6 +207,23 @@ static int vncPointerProc(DeviceIntPtr pDevice, int onoff)
 		btn_labels[5] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_HWHEEL_LEFT);
 		btn_labels[6] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_HWHEEL_RIGHT);
 
+		/*
+		 * The labels BTN_LABEL_PROP_BTN_SIDE and BTN_LABEL_PROP_BTN_EXTRA
+		 * represent the side buttons on mice that are typically used to
+		 * navigate back/forward respectively in web browsers.
+		 *
+		 * In X11, these labels are mapped to the BTN_SIDE and BTN_EXTRA
+		 * input codes, which are mapped in the Linux HID driver. These
+		 * are not to be confused with the BTN_FORWARD and BTN_BACK input
+		 * codes, which some applications also use for back/forward
+		 * navigation.
+		 *
+		 * It seems like most mice have their side buttons mapped to
+		 * BTN_SIDE and BTN_EXTRA.
+		 */
+		btn_labels[7] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_SIDE);
+		btn_labels[8] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_EXTRA);
+
 		axes_labels[0] = XIGetKnownProperty(AXIS_LABEL_PROP_REL_X);
 		axes_labels[1] = XIGetKnownProperty(AXIS_LABEL_PROP_REL_Y);