From 93a050c3ad2d2264d3880db3791387b1a9bf2e9e Mon Sep 17 00:00:00 2001 From: Tatu Frisk Date: Tue, 14 Mar 2017 14:41:27 +0200 Subject: Fix hanging issue in _XReply Assume event queue is empty if another thread is blocking waiting for event. If one thread was blocking waiting for an event and another thread sent a reply to the X server, both threads got blocked until an event was received. Signed-off-by: Tatu Frisk Signed-off-by: Jose Alarcon --- src/xcb_io.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) (limited to 'src') diff --git a/src/xcb_io.c b/src/xcb_io.c index 4be75408..dff441ff 100644 --- a/src/xcb_io.c +++ b/src/xcb_io.c @@ -704,18 +704,14 @@ Status _XReply(Display *dpy, xReply *rep, int extra, Bool discard) if(dpy->xcb->event_owner == XlibOwnsEventQueue) { xcb_generic_reply_t *event; - /* If some thread is already waiting for events, - * it will get the first one. That thread must - * process that event before we can continue. */ - /* FIXME: That event might be after this reply, - * and might never even come--or there might be - * multiple threads trying to get events. */ - while(dpy->xcb->event_waiter) - { /* need braces around ConditionWait */ - ConditionWait(dpy, dpy->xcb->event_notify); - } - while((event = poll_for_event(dpy, True))) - handle_response(dpy, event, True); + + /* Assume event queue is empty if another thread is blocking + * waiting for event. */ + if(!dpy->xcb->event_waiter) + { + while((event = poll_for_response(dpy))) + handle_response(dpy, event, True); + } } req->reply_waiter = 0; -- cgit v1.2.1