[PATCH] dix: Use DeliverGrabbedEvent for implicit passive grabs (#25400)

[Peter Hutterer]

A client requesting a GrabModeSync button grab, owner-events true, with only
the ButtonRelease mask set would never receive the press event even if the
grab window had the ButtonPress mask set.

The protocol requires that if owner-events is true, then the delivery mask
is the combination of the grab mask + the window event mask.

DeliverGrabbedEvents does this already for us, checking first the delivery
based on owner_events and then based on the grab mask. AFAICT, the device
cannot enter the states FREEZE_BOTH_NEXT_EVENT or FREEZE_NEXT_EVENT that
would be handled by DGE in any possible path here.

Bonus point - CheckPassiveGrabsOnWindows suddenly becomes a lot lesss
complicated.

X.Org Bug 25400 <http://bugs.freedesktop.org/show_bug.cgi?id=25400>
---

This is the second version of the patch to address the same issue, previous
one was rejected by Keith.

Keith, I'll leave that in your court, please apply to master as you see fit,
I won't include it in my pull requests to avoid duplication.

Cheers,
  Peter

 dix/events.c |   63 +---------------------------------------------------------
 1 files changed, 1 insertions(+), 62 deletions(-)

diff --git a/dix/events.c b/dix/events.c
index 4eb8afa..30cbadf 100644
--- a/dix/events.c
+++ b/dix/events.c
@@ -3458,7 +3458,6 @@ CheckPassiveGrabsOnWindow(
     {
 	DeviceIntPtr	gdev;
 	XkbSrvInfoPtr	xkbi = NULL;
-	Mask		mask = 0;
 
 	gdev= grab->modifierDevice;
         if (grab->grabtype == GRABTYPE_CORE)
@@ -3511,10 +3510,6 @@ CheckPassiveGrabsOnWindow(
 	     (grab->confineTo->realized &&
 				BorderSizeNotEmpty(device, grab->confineTo))))
 	{
-            int rc, count = 0;
-            xEvent *xE = NULL;
-            xEvent core;
-
             event->corestate &= 0x1f00;
             event->corestate |= tempGrab.modifiersDetail.exact & (~0x1f00);
             grabinfo = &device->deviceGrab;
@@ -3561,62 +3556,8 @@ CheckPassiveGrabsOnWindow(
             }
 
 
-            if (match & CORE_MATCH)
-            {
-                rc = EventToCore((InternalEvent*)event, &core);
-                if (rc != Success)
-                {
-                    if (rc != BadMatch)
-                        ErrorF("[dix] %s: core conversion failed in CPGFW "
-                                "(%d, %d).\n", device->name, event->type, rc);
-                    continue;
-                }
-                xE = &core;
-                count = 1;
-                mask = grab->eventMask;
-            } else if (match & XI2_MATCH)
-            {
-                rc = EventToXI2((InternalEvent*)event, &xE);
-                if (rc != Success)
-                {
-                    if (rc != BadMatch)
-                        ErrorF("[dix] %s: XI2 conversion failed in CPGFW "
-                                "(%d, %d).\n", device->name, event->type, rc);
-                    continue;
-                }
-                count = 1;
-
-                /* FIXME: EventToXI2 returns NULL for enter events, so
-                 * dereferencing the event is bad. Internal event types are
-                 * aligned with core events, so the else clause is valid.
-                 * long-term we should use internal events for enter/focus
-                 * as well */
-                if (xE)
-                    mask = grab->xi2mask[device->id][((xGenericEvent*)xE)->evtype/8];
-                else if (event->type == XI_Enter || event->type == XI_FocusIn)
-                    mask = grab->xi2mask[device->id][event->type/8];
-            } else
-            {
-                rc = EventToXI((InternalEvent*)event, &xE, &count);
-                if (rc != Success)
-                {
-                    if (rc != BadMatch)
-                        ErrorF("[dix] %s: XI conversion failed in CPGFW "
-                                "(%d, %d).\n", device->name, event->type, rc);
-                    continue;
-                }
-                mask = grab->eventMask;
-            }
-
 	    (*grabinfo->ActivateGrab)(device, grab, currentTime, TRUE);
-
-            if (xE)
-            {
-                FixUpEventFromWindow(device, xE, grab->window, None, TRUE);
-
-                TryClientEvents(rClient(grab), device, xE, count, mask,
-                                       GetEventFilter(device, xE), grab);
-            }
+            DeliverGrabbedEvent((InternalEvent*)event, device, FALSE);
 
 	    if (grabinfo->sync.state == FROZEN_NO_EVENT)
 	    {
@@ -3626,8 +3567,6 @@ CheckPassiveGrabsOnWindow(
 		grabinfo->sync.state = FROZEN_WITH_EVENT;
             }
 
-            if (match & (XI_MATCH | XI2_MATCH))
-                xfree(xE); /* on core match xE == &core */
 	    return TRUE;
 	}
     }
-- 
1.6.6.1