mi: ensure chained button mappings from SD -> MD (#19282)

After copying the master event, flip the detail field to the mapped button of
the SD, not the physical button. This way if the SD has a mapping 1:3 and the
MD has a mapping of 3:4, a press on button 1 on the SD results in a core event
on button 4.

X.Org Bug 19282 <http://bugs.freedesktop.org/show_bug.cgi?id=19282>

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

2 files changed, 25 insertions, 3 deletions

diff --git a/mi/mieq.c b/mi/mieq.c
index 963f27c01..3ce3c49d3 100644
--- a/mi/mieq.c
+++ b/mi/mieq.c
@@ -320,21 +320,38 @@ ChangeDeviceID(DeviceIntPtr dev, xEvent* event)
                     ((xGenericEvent*)event)->extension,
                     ((xGenericEvent*)event)->evtype);
     } else
         DebugF("[mi] Unknown event type (%d), cannot change id.\n", type);
 }
 
+static void
+FixUpEventForMaster(DeviceIntPtr mdev, DeviceIntPtr sdev, xEvent* original,
+                    EventListPtr master, int count)
+{
+    /* Ensure chained button mappings, i.e. that the detail field is the
+     * value of the mapped button on the SD, not the physical button */
+    if (original->u.u.type == DeviceButtonPress || original->u.u.type == DeviceButtonRelease)
+    {
+        int btn = original->u.u.detail;
+        if (!sdev->button)
+            return; /* Should never happen */
+
+        master->event->u.u.detail = sdev->button->map[btn];
+    }
+}
+
 /**
  * Copy the given event into master.
  * @param mdev The master device
+ * @param sdev The slave device the original event comes from
  * @param original The event as it came from the EQ
  * @param master The event after being copied
  * @param count Number of events in original.
  */
 void
-CopyGetMasterEvent(DeviceIntPtr mdev, xEvent* original,
+CopyGetMasterEvent(DeviceIntPtr mdev, DeviceIntPtr sdev, xEvent* original,
                    EventListPtr master, int count)
 {
     int len = count * sizeof(xEvent);
 
     /* Assumption: GenericEvents always have count 1 */
 
@@ -343,15 +360,20 @@ CopyGetMasterEvent(DeviceIntPtr mdev, xEvent* original,
 
     if (master->evlen < len)
         SetMinimumEventSize(master, 1, len);
 
     memcpy(master->event, original, len);
     while (count--)
+    {
         ChangeDeviceID(mdev, &master->event[count]);
+        FixUpEventForMaster(mdev, sdev, original, master, count);
+    }
 }
 
+
+
 /* Call this from ProcessInputEvents(). */
 void
 mieqProcessInputEvents(void)
 {
     mieqHandler handler;
     EventRec *e = NULL;
@@ -416,13 +438,13 @@ mieqProcessInputEvents(void)
             x = event->u.keyButtonPointer.rootX;
             y = event->u.keyButtonPointer.rootY;
             NewCurrentScreen (dev, DequeueScreen(dev), x, y);
         }
         else {
             if (master)
-                CopyGetMasterEvent(master, event, masterEvents, nevents);
+                CopyGetMasterEvent(master, dev, event, masterEvents, nevents);
 
             /* If someone's registered a custom event handler, let them
              * steal it. */
             if (handler)
             {
                 handler(DequeueScreen(dev)->myNum, event, dev, nevents);
diff --git a/xkb/ddxDevBtn.c b/xkb/ddxDevBtn.c
index 709efc13a..03fb440fe 100644
--- a/xkb/ddxDevBtn.c
+++ b/xkb/ddxDevBtn.c
@@ -113,13 +113,13 @@ DeviceIntPtr		master = NULL;
             SetMinimumEventSize(masterEvents, 1, (1 + MAX_VALUATOR_EVENTS) * sizeof(xEvent));
         }
         master = dev->u.master;
         if (!IsPointerDevice(master))
             master = GetPairedDevice(dev->u.master);
 
-        CopyGetMasterEvent(master, &events, masterEvents, count);
+        CopyGetMasterEvent(master, dev, &events, masterEvents, count);
     }
 
     (*dev->public.processInputProc)((xEventPtr)btn, dev, count);
 
     if (master) {
         (*master->public.processInputProc)(masterEvents->event, master, count);