diff --git a/common/xrdp_constants.h b/common/xrdp_constants.h
index 76c12c13..57f3439b 100644
--- a/common/xrdp_constants.h
+++ b/common/xrdp_constants.h
@@ -201,6 +201,11 @@
 #define PTRFLAGS_BUTTON2               0x2000
 #define PTRFLAGS_BUTTON3               0x4000
 
+/* Mouse Event (MS-RDPBCGR 2.2.8.1.1.3.1.1.4) */
+#define PTRXFLAGS_DOWN                 0x8000
+#define PTRXFLAGS_BUTTON1              0x0001
+#define PTRXFLAGS_BUTTON2              0x0002
+
 /* Raster operation masks */
 #define ROP2_S(rop3)                   (rop3 & 0xf)
 #define ROP2_P(rop3)                   ((rop3 & 0x3) | ((rop3 & 0x30) >> 2))
diff --git a/xrdp/xrdp_wm.c b/xrdp/xrdp_wm.c
index 7379979d..3d16fe63 100644
--- a/xrdp/xrdp_wm.c
+++ b/xrdp/xrdp_wm.c
@@ -1722,24 +1722,24 @@ static int
 xrdp_wm_process_input_mousex(struct xrdp_wm* self, int device_flags,
                              int x, int y)
 {
-    if (device_flags & 0x8000) /* PTRXFLAGS_DOWN */
+    if (device_flags & PTRXFLAGS_DOWN)
     {
-        if (device_flags & 0x0001) /* PTRXFLAGS_BUTTON1 */
+        if (device_flags & PTRXFLAGS_BUTTON1)
         {
             xrdp_wm_mouse_click(self, x, y, 6, 1);
         }
-        else if (device_flags & 0x0002) /* PTRXFLAGS_BUTTON2 */
+        else if (device_flags & PTRXFLAGS_BUTTON2)
         {
             xrdp_wm_mouse_click(self, x, y, 7, 1);
         }
     }
     else
     {
-        if (device_flags & 0x0001) /* PTRXFLAGS_BUTTON1 */
+        if (device_flags & PTRXFLAGS_BUTTON1)
         {
             xrdp_wm_mouse_click(self, x, y, 6, 0);
         }
-        else if (device_flags & 0x0002) /* PTRXFLAGS_BUTTON2 */
+        else if (device_flags & PTRXFLAGS_BUTTON2)
         {
             xrdp_wm_mouse_click(self, x, y, 7, 0);
         }