[Xcb] [PATCH 1/1] read from connection when polling special events and replies

[David McFarland]

Using the mesa vulkan driver, if you acquire an image from a
swapchain using a finite timeout (x11_acquire_next_image_poll_x11),
it will occasionally lock, calling xcb_poll_for_special_event in
a loop until the timeout expires.

Call _xcb_in_read() once from the polling functions for special
events and replies, in the same way as xcb_poll_for_event.

Signed-off-by: David McFarland <corngood at gmail.com>
---
 src/xcb_in.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/xcb_in.c b/src/xcb_in.c
index bab4bc7..73209e0 100644
--- a/src/xcb_in.c
+++ b/src/xcb_in.c
@@ -661,6 +661,8 @@ int xcb_poll_for_reply(xcb_connection_t *c, unsigned int request, void **reply,
     assert(reply != 0);
     pthread_mutex_lock(&c->iolock);
     ret = poll_for_reply(c, widen(c, request), reply, error);
+    if(!ret && c->in.reading == 0 && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */
+        ret = poll_for_reply(c, widen(c, request), reply, error);
     pthread_mutex_unlock(&c->iolock);
     return ret;
 }
@@ -678,6 +680,8 @@ int xcb_poll_for_reply64(xcb_connection_t *c, uint64_t request, void **reply, xc
     assert(reply != 0);
     pthread_mutex_lock(&c->iolock);
     ret = poll_for_reply(c, request, reply, error);
+    if(!ret && c->in.reading == 0 && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */
+        ret = poll_for_reply(c, request, reply, error);
     pthread_mutex_unlock(&c->iolock);
     return ret;
 }
@@ -768,6 +772,8 @@ xcb_generic_event_t *xcb_poll_for_special_event(xcb_connection_t *c,
         return 0;
     pthread_mutex_lock(&c->iolock);
     event = get_special_event(c, se);
+    if(!event && c->in.reading == 0 && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */
+        event = get_special_event(c, se);
     pthread_mutex_unlock(&c->iolock);
     return event;
 }
-- 
2.12.2