[PATCH 2/2] Keep virtual core pointer touch class around if new slave doesn't have one

[Chase Douglas]

The VCP may have active touch grabs. The touch records must be kept so
these touch grabs may be accepted/rejected in the future. This means the
touch class list will not represent the touch class of the attached
slave device if it does not have a touch class, but we already were
breaking that assumption by keeping a separate touches array for the
VCP.

Signed-off-by: Chase Douglas <chase.douglas at canonical.com>
---
I haven't seen this cause a crash in the wild, and I haven't stress tested it,
but I don't see how accept/reject could work after we switch to a non-touch
slave device without this change.

 Xi/exevents.c |    9 +++------
 1 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/Xi/exevents.c b/Xi/exevents.c
index 51f991c..069a52c 100644
--- a/Xi/exevents.c
+++ b/Xi/exevents.c
@@ -699,13 +699,10 @@ DeepCopyPointerClasses(DeviceIntPtr from, DeviceIntPtr to)
         to->touch->touches = to_touches_array_tmp;
         to->touch->num_touches = to_num_touches_tmp;
         to->touch->sourceid = from->id;
-    } else if (to->touch)
-    {
-        ClassesPtr classes;
-        classes = to->unused_classes;
-        classes->touch = to->touch;
-        to->touch      = NULL;
     }
+    /* Don't remove touch class if from->touch is non-existent. The to device
+     * may have an active touch grab, so we need to keep the touch class record
+     * around. */
 }
 
 /**
-- 
1.7.9