[PATCH xserver] AttendClient of grab-pervious client should queue to saved_ready_clients

[Keith Packard]

A client which is attended while a grab is blocking execution of its
requests needs to be placed in the saved_ready_clients list so that it
will get scheduled once the grab terminates. Otherwise, if the client
never sends another request, there is no way for it to be placed in
the ready_clients list.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99333
Signed-off-by: Keith Packard <keithp at keithp.com>
---
 dix/dispatch.c      | 7 +++++++
 include/dixstruct.h | 3 +++
 os/connection.c     | 4 ++++
 3 files changed, 14 insertions(+)

diff --git a/dix/dispatch.c b/dix/dispatch.c
index 3d0fe26fd..ab69d34b9 100644
--- a/dix/dispatch.c
+++ b/dix/dispatch.c
@@ -266,6 +266,13 @@ mark_client_ready(ClientPtr client)
         xorg_list_append(&client->ready, &ready_clients);
 }
 
+/* Client has requests queued or data on the network, but awaits a server grab release */
+void mark_client_saved_ready(ClientPtr client)
+{
+    if (xorg_list_is_empty(&client->ready))
+        xorg_list_append(&client->ready, &saved_ready_clients);
+}
+
 /* Client has no requests queued and no data on network */
 void
 mark_client_not_ready(ClientPtr client)
diff --git a/include/dixstruct.h b/include/dixstruct.h
index d71b0ac05..fd9195972 100644
--- a/include/dixstruct.h
+++ b/include/dixstruct.h
@@ -143,6 +143,9 @@ extern void SmartScheduleStopTimer(void);
 /* Client has requests queued or data on the network */
 void mark_client_ready(ClientPtr client);
 
+/* Client has requests queued or data on the network, but awaits a server grab release */
+void mark_client_saved_ready(ClientPtr client);
+
 /* Client has no requests queued and no data on network */
 void mark_client_not_ready(ClientPtr client);
 
diff --git a/os/connection.c b/os/connection.c
index a901ebf3c..a2629c8a2 100644
--- a/os/connection.c
+++ b/os/connection.c
@@ -1067,6 +1067,10 @@ AttendClient(ClientPtr client)
     set_poll_client(client);
     if (listen_to_client(client))
         mark_client_ready(client);
+    else if (!(oc->flags & OS_COMM_IGNORED)) {
+        /* grab active, mark ready when grab goes away */
+        mark_client_saved_ready(client);
+    }
 }
 
 /* make client impervious to grabs; assume only executing client calls this */
-- 
2.11.0