dix: when a window disappears, remove it from the touch sprite trace

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Chase Douglas <chase.douglas@canonical.com>

Xi/exevents.c

@@ -1866,6 +1866,36 @@ InputClientGone(WindowPtr pWin, XID id)
     FatalError("client not on device event list");
 }
 
+/**
+ * Search for window in each touch trace for each device. Remove the window
+ * and all its subwindows from the trace when found. The initial window
+ * order is preserved.
+ */
+void WindowGone(WindowPtr win)
+{
+    DeviceIntPtr dev;
+
+    for (dev = inputInfo.devices; dev; dev = dev->next) {
+        TouchClassPtr t = dev->touch;
+        int i;
+
+        if (!t)
+            continue;
+
+        for (i = 0; i < t->num_touches; i++) {
+            SpritePtr sprite = &t->touches[i].sprite;
+            int j;
+
+            for (j = 0; j < sprite->spriteTraceGood; j++) {
+                if (sprite->spriteTrace[j] == win) {
+                    sprite->spriteTraceGood = j;
+                    break;
+                }
+            }
+        }
+    }
+}
+
 int
 SendEvent(ClientPtr client, DeviceIntPtr d, Window dest, Bool propagate,
 	  xEvent * ev, Mask mask, int count)

dix/window.c

@@ -131,6 +131,7 @@ Equipment Corporation.
 
 #include "privates.h"
 #include "xace.h"
+#include "exevents.h"
 
 #include <X11/Xatom.h> /* must come after server includes */
 
@@ -2971,8 +2972,10 @@ UnmapWindow(WindowPtr pWin, Bool fromConfigure)
 	if (!fromConfigure && pScreen->PostValidateTree)
 	    (*pScreen->PostValidateTree)(pLayerWin->parent, pWin, VTUnmap);
     }
-    if (wasRealized && !fromConfigure)
+    if (wasRealized && !fromConfigure) {
 	WindowsRestructured ();
+	WindowGone(pWin);
+    }
     return Success;
 }
 
@@ -3055,8 +3058,10 @@ UnmapSubwindows(WindowPtr pWin)
 	if (anyMarked && pScreen->PostValidateTree)
 	    (*pScreen->PostValidateTree)(pLayerWin->parent, pHead, VTUnmap);
     }
-    if (wasRealized)
+    if (wasRealized) {
 	WindowsRestructured ();
+	WindowGone(pWin);
+    }
 }
 
 

include/exevents.h

@@ -245,6 +245,10 @@ InputClientGone(
 	WindowPtr              /* pWin */,
 	XID                    /* id */);
 
+extern void
+WindowGone(
+	WindowPtr              /* win */);
+
 extern int
 SendEvent (
 	ClientPtr              /* client */,