From c28a87053b36628baa8a7befb18c52d90579637c Mon Sep 17 00:00:00 2001
From: "Enrico Weigelt, metux IT consult" <info@metux.net>
Date: Wed, 4 Sep 2024 13:13:01 +0200
Subject: [PATCH] dix: make FreeGrab() NULL tolerant

Allow NULL parameters to be passed to FreeGrab(), so callers don't all
need to check on their own anymore.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
(cherry picked from commit 48cee2fd22d1d84f5f4ee0b316bd3ad7359c015f)
---
 dix/devices.c  |  3 +--
 dix/events.c   | 12 ++++--------
 dix/gestures.c |  6 ++----
 dix/grabs.c    |  3 ++-
 4 files changed, 9 insertions(+), 15 deletions(-)

diff --git a/dix/devices.c b/dix/devices.c
index 4d853298f..491a012df 100644
--- a/dix/devices.c
+++ b/dix/devices.c
@@ -1033,8 +1033,7 @@ CloseDevice(DeviceIntPtr dev)
         }
     }
 
-    if (dev->deviceGrab.grab)
-        FreeGrab(dev->deviceGrab.grab);
+    FreeGrab(dev->deviceGrab.grab);
     free(dev->deviceGrab.sync.event);
     free(dev->config_info);     /* Allocated in xf86ActivateDevice. */
     free(dev->last.scroll);
diff --git a/dix/events.c b/dix/events.c
index 4a51439dd..4275b8855 100644
--- a/dix/events.c
+++ b/dix/events.c
@@ -1525,8 +1525,7 @@ UpdateTouchesForGrab(DeviceIntPtr mouse)
             listener->window = grab->window;
             listener->state = TOUCH_LISTENER_IS_OWNER;
 
-            if (listener->grab)
-                FreeGrab(listener->grab);
+            FreeGrab(listener->grab);
             listener->grab = AllocGrab(grab);
         }
     }
@@ -1566,8 +1565,7 @@ UpdateGesturesForGrab(DeviceIntPtr mouse)
         listener->listener = grab->resource;
         listener->window = grab->window;
 
-        if (listener->grab)
-            FreeGrab(listener->grab);
+        FreeGrab(listener->grab);
         listener->grab = AllocGrab(grab);
     }
 }
@@ -1625,8 +1623,7 @@ ActivatePointerGrab(DeviceIntPtr mouse, GrabPtr grab,
     UpdateGesturesForGrab(mouse);
     CheckGrabForSyncs(mouse, (Bool) grab->pointerMode,
                       (Bool) grab->keyboardMode);
-    if (oldgrab)
-        FreeGrab(oldgrab);
+    FreeGrab(oldgrab);
 }
 
 /**
@@ -1745,8 +1742,7 @@ ActivateKeyboardGrab(DeviceIntPtr keybd, GrabPtr grab, TimeStamp time,
     grabinfo->implicitGrab = passive & ImplicitGrabMask;
     CheckGrabForSyncs(keybd, (Bool) grab->keyboardMode,
                       (Bool) grab->pointerMode);
-    if (oldgrab)
-        FreeGrab(oldgrab);
+    FreeGrab(oldgrab);
 }
 
 /**
diff --git a/dix/gestures.c b/dix/gestures.c
index 60eba9a4c..ea8d13d47 100644
--- a/dix/gestures.c
+++ b/dix/gestures.c
@@ -114,10 +114,8 @@ void
 GestureEndGesture(GestureInfoPtr gi)
 {
     if (gi->has_listener) {
-        if (gi->listener.grab) {
-            FreeGrab(gi->listener.grab);
-            gi->listener.grab = NULL;
-        }
+        FreeGrab(gi->listener.grab);
+        gi->listener.grab = NULL;
         gi->listener.listener = 0;
         gi->has_listener = FALSE;
     }
diff --git a/dix/grabs.c b/dix/grabs.c
index 66c498cd3..f72deb4c3 100644
--- a/dix/grabs.c
+++ b/dix/grabs.c
@@ -254,7 +254,8 @@ CreateGrab(int client, DeviceIntPtr device, DeviceIntPtr modDevice,
 void
 FreeGrab(GrabPtr pGrab)
 {
-    BUG_RETURN(!pGrab);
+    if (!pGrab)
+        return;
 
     free(pGrab->modifiersDetail.pMask);
     free(pGrab->detail.pMask);