dix: When the last slave is removed, set master to the original classes.

DeviceClassesChangedEvent is sent to the client, where device == new slave.

Xi/exevents.c

@@ -162,25 +162,10 @@ ProcessOtherEvent(xEventPtr xE, DeviceIntPtr device, int count)
 
         /* event is already correct size, see comment in GetPointerEvents */
         classbuff = (char*)&xE[1];
-        if (master->key) 
-        {
-            /* we don't actually swap here, swapping is done later */
-            CopySwapKeyClass(NullClient, master->key, &classbuff);
-            dcce->num_classes++;
-        }
-        if (master->button) 
-        {
-            CopySwapButtonClass(NullClient, master->button, &classbuff);
-            dcce->num_classes++;
-        }
-        if (master->valuator)
-        {
-            CopySwapValuatorClass(NullClient, master->valuator, &classbuff);
-            dcce->num_classes++;
-        }
-
-        SendEventToAllWindows(master, XI_DeviceClassesChangedMask,
-                              xE, 1);
+        /* we don't actually swap if there's a NullClient, swapping is done
+         * later when event is delivered. */
+        CopySwapClasses(NullClient, master, &dcce->num_classes, &classbuff);
+        SendEventToAllWindows(master, XI_DeviceClassesChangedMask, xE, 1);
         return;
     }
 

Xi/listdev.c

@@ -142,7 +142,7 @@ CopyDeviceName(char **namebuf, char *name)
  *
  */
 
-void
+static void
 CopySwapButtonClass(ClientPtr client, ButtonClassPtr b, char **buf)
 {
     char n;
@@ -201,7 +201,7 @@ CopySwapDevice(ClientPtr client, DeviceIntPtr d, int num_classes,
  *
  */
 
-void
+static void
 CopySwapKeyClass(ClientPtr client, KeyClassPtr k, char **buf)
 {
     char n;
@@ -231,7 +231,7 @@ CopySwapKeyClass(ClientPtr client, KeyClassPtr k, char **buf)
  *
  */
 
-int
+static int
 CopySwapValuatorClass(ClientPtr client, ValuatorClassPtr v, char **buf)
 {
     int i, j, axes, t_axes;
@@ -286,17 +286,24 @@ ListDeviceInfo(ClientPtr client, DeviceIntPtr d, xDeviceInfoPtr dev,
 {
     CopyDeviceName(namebuf, d->name);
     CopySwapDevice(client, d, 0, devbuf);
-    if (d->key != NULL) {
-	CopySwapKeyClass(client, d->key, classbuf);
-	dev->num_classes++;
+    CopySwapClasses(client, d, &dev->num_classes, classbuf);
+}
+
+void
+CopySwapClasses(ClientPtr client, DeviceIntPtr dev, CARD8 *num_classes,
+                char** classbuf)
+{
+    if (dev->key != NULL) {
+	CopySwapKeyClass(client, dev->key, classbuf);
+	(*num_classes)++;
     }
-    if (d->button != NULL) {
-	CopySwapButtonClass(client, d->button, classbuf);
-	dev->num_classes++;
+    if (dev->button != NULL) {
+	CopySwapButtonClass(client, dev->button, classbuf);
+	(*num_classes)++;
     }
-    if (d->valuator != NULL) {
-	dev->num_classes +=
-	    CopySwapValuatorClass(client, d->valuator, classbuf);
+    if (dev->valuator != NULL) {
+	(*num_classes) +=
+	    CopySwapValuatorClass(client, dev->valuator, classbuf);
     }
 }
 

Xi/listdev.h

@@ -44,15 +44,9 @@ void SRepXListInputDevices(ClientPtr /* client */ ,
     );
 
 void
-CopySwapKeyClass(ClientPtr /* client */, 
-                 KeyClassPtr /* k */, 
-                 char** /* buf */);
-void
-CopySwapButtonClass(ClientPtr /* client */, 
-                    ButtonClassPtr /* b */, 
-                    char** /* buf */);
-int
-CopySwapValuatorClass(ClientPtr /* client */, 
-                      ValuatorClassPtr /* v */, 
-                      char** /* buf */);
+CopySwapClasses(ClientPtr /* client */,
+                DeviceIntPtr /* dev */,
+                CARD8* /* num_classes */,
+                char** /* classbuf */);
+
 #endif /* LISTDEV_H */

dix/devices.c

@@ -79,6 +79,7 @@ SOFTWARE.
 #include <X11/extensions/XIproto.h>
 #include "exglobals.h"
 #include "exevents.h"
+#include "listdev.h" /* for CopySwapXXXClass */
 
 /** @file
  * This file handles input device-related stuff.
@@ -2314,9 +2315,50 @@ AttachDevice(ClientPtr client, DeviceIntPtr dev, DeviceIntPtr master)
      */
     if (!master)
     {
+        DeviceIntPtr it;
                               /* current root window */
         InitializeSprite(dev, dev->spriteInfo->sprite->spriteTrace[0]);
         dev->spriteInfo->spriteOwner = FALSE;
+
+        /* the master may need to restore the original classes, search for a
+         * device that is still paired with our master. */
+        for (it = inputInfo.devices; it; it = it->next)
+            if (!it->isMaster && it->u.master == master)
+                break;
+
+        if (!it)  /* no dev is paired with our master */
+        {
+            ClassesPtr classes;
+            EventList event = { NULL, 0};
+            char* classbuf;
+
+            classes = master->devPrivates[MasterDevClassesPrivIdx].ptr;
+            master->key = classes->key;
+            master->valuator = classes->valuator;
+            master->button = classes->button;
+            master->focus = classes->focus;
+            master->proximity = classes->proximity;
+            master->absolute = classes->absolute;
+            master->kbdfeed = classes->kbdfeed;
+            master->ptrfeed = classes->ptrfeed;
+            master->intfeed = classes->intfeed;
+            master->stringfeed = classes->stringfeed;
+            master->bell = classes->bell;
+            master->leds = classes->leds;
+
+            /* Send event to clients */
+            CreateClassesChangedEvent(&event, master, master);
+            deviceClassesChangedEvent *dcce = 
+                        (deviceClassesChangedEvent*)event.event;
+            dcce->deviceid = master->id;
+            dcce->num_classes = 0;
+            classbuf = (char*)&event.event[1];
+            CopySwapClasses(NullClient, master, &dcce->num_classes, &classbuf);
+            SendEventToAllWindows(master, XI_DeviceClassesChangedMask, 
+                    event.event, 1);
+            xfree(event.event);
+        }
+
     } else
         dev->spriteInfo->sprite = master->spriteInfo->sprite;
 

dix/getevents.c

@@ -111,7 +111,7 @@ key_autorepeats(DeviceIntPtr pDev, int key_code)
               (1 << (key_code & 7)));
 }
 
-static void
+void
 CreateClassesChangedEvent(EventList* event, 
                           DeviceIntPtr master, 
                           DeviceIntPtr slave)

include/input.h

@@ -402,6 +402,9 @@ extern int GetMaximumEventsNum(void);
 extern EventListPtr InitEventList(int num_events);
 extern void FreeEventList(EventListPtr list, int num_events);
 
+extern void CreateClassesChangedEvent(EventListPtr event, 
+                                      DeviceIntPtr master,
+                                      DeviceIntPtr slave);
 extern int GetPointerEvents(
     EventListPtr events,
     DeviceIntPtr pDev,