From 98e3db2ac43d4a3f13475cb160c8ce0155ac7d61 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marco=20Trevisan=20=28Trevi=C3=B1o=29?= <mail@3v1n0.net>
Date: Fri, 26 Oct 2018 19:52:49 +0200
Subject: [PATCH] Xi: Use current device active grab to deliver touch events if
 any

When Retrieving touch delivery data we need to check if we have an active
grab on such device, and in that case use it to delivery events.
If we don't do this, when rejecting the touch events in DeactivatePointerGrab,
we will end-up in creating an implicit grab that will change the device
deviceGrab's state, causing a recursion during TouchEndTouch.

Fixes #7

https://bugs.freedesktop.org/show_bug.cgi?id=96536
(cherry picked from commit 35e5a76cc1d02801fadd49d12e60664b02e4bebc)
---
 Xi/exevents.c | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/Xi/exevents.c b/Xi/exevents.c
index 17d751e31..659816a46 100644
--- a/Xi/exevents.c
+++ b/Xi/exevents.c
@@ -1293,14 +1293,21 @@ RetrieveTouchDeliveryData(DeviceIntPtr dev, TouchPointInfoPtr ti,
     int rc;
     InputClients *iclients = NULL;
     *mask = NULL;
+    *grab = NULL;
 
     if (listener->type == LISTENER_GRAB ||
         listener->type == LISTENER_POINTER_GRAB) {
-
         *grab = listener->grab;
 
         BUG_RETURN_VAL(!*grab, FALSE);
+    }
+    else if (ti->emulate_pointer && dev->deviceGrab.grab &&
+             !dev->deviceGrab.fromPassiveGrab) {
+        /* There may be an active pointer grab on the device */
+        *grab = dev->deviceGrab.grab;
+    }
 
+    if (*grab) {
         *client = rClient(*grab);
         *win = (*grab)->window;
         *mask = (*grab)->xi2mask;
@@ -1357,8 +1364,6 @@ RetrieveTouchDeliveryData(DeviceIntPtr dev, TouchPointInfoPtr ti,
             /* if owner selected, oclients is NULL */
             *client = oclients ? rClient(oclients) : wClient(*win);
         }
-
-        *grab = NULL;
     }
 
     return TRUE;
@@ -1498,16 +1503,6 @@ DeliverEmulatedMotionEvent(DeviceIntPtr dev, TouchPointInfoPtr ti,
                                        &mask))
             return;
 
-        /* There may be a pointer grab on the device */
-        if (!grab) {
-            grab = dev->deviceGrab.grab;
-            if (grab) {
-                win = grab->window;
-                mask = grab->xi2mask;
-                client = rClient(grab);
-            }
-        }
-
         DeliverTouchEmulatedEvent(dev, ti, (InternalEvent*)&motion, &ti->listeners[0], client,
                                   win, grab, mask);
     }