master 6fb206329f 2/2: ; * src/xterm.c (x_if_event): Minor speed improvements.

[Po Lu]

branch: master
commit 6fb206329f9c3f14154bd425e08b2e72e7f31855
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    ; * src/xterm.c (x_if_event): Minor speed improvements.
---
 src/xterm.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/xterm.c b/src/xterm.c
index eb1a557e88..f82340958e 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -6605,12 +6605,17 @@ x_if_event (Display *dpy, XEvent *event_return,
   current_time = current_timespec ();
   target = timespec_add (current_time, timeout);
 
+  /* Check if an event is already in the queue.  If it is, avoid
+     syncing.  */
+  if (XCheckIfEvent (dpy, event_return, predicate, arg))
+    return 0;
+
   while (true)
     {
       /* Get events into the queue.  */
       XSync (dpy, False);
 
-      /* Check if an event is now in the queue.  */
+      /* Look for an event again.  */
       if (XCheckIfEvent (dpy, event_return, predicate, arg))
        return 0;