From 9a067a31050292a9b12e2fa055ca12f7ff4937e2 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Fri, 29 Nov 2013 19:38:27 +0000
Subject: [PATCH] xduplic-copier: do not call XmuClientWindow on a null
 subwindow

If you click on the root window, xduplic-copier gets an event with
subwindow==0.  Current XmuClientWindow crashes if you call it with a
null window.

Instead, shortcut this: look for subwindow==0 as the way to tell it's
the root window.
---
 cprogs/xduplic-copier.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/cprogs/xduplic-copier.c b/cprogs/xduplic-copier.c
index 8c1da08..80374f9 100644
--- a/cprogs/xduplic-copier.c
+++ b/cprogs/xduplic-copier.c
@@ -144,8 +144,7 @@ static void buttonpress(XButtonEvent *e) {
 
   if (e->window != e->root) return;
 
-  sw= XmuClientWindow(display, e->subwindow);
-  if (!sw) {
+  if (!e->subwindow) {
     if (!rightbutton) {
       stopselecting();
     } else {
@@ -160,6 +159,8 @@ static void buttonpress(XButtonEvent *e) {
     return;
   }
 
+  sw= XmuClientWindow(display, e->subwindow);
+
   if (sw == w) { beep(); return; }
 
   for (ownp=&headwn;
-- 
2.30.2