mi: Add a callback to notify driver about input event submission

This is useful for mock input drivers that control the server in
integration tests. Given that input submission happens on a different
thread than processing, it's otherwise impossible for the driver to
synchronize with the completion of the processing of submitted events.

Signed-off-by: Povilas Kanapickas <povilas@radix.lt>

2 files changed, 24 insertions, 0 deletions

diff --git a/mi/mi.h b/mi/mi.h
index 2cd3066c1..8b0a231ca 100644
--- a/mi/mi.h
+++ b/mi/mi.h
@@ -205,6 +205,12 @@ extern _X_EXPORT void mieqProcessDeviceEvent(DeviceIntPtr /* dev */ ,
 extern _X_EXPORT void mieqProcessInputEvents(void
     );
 
+extern _X_EXPORT void mieqAddCallbackOnDrained(CallbackProcPtr callback,
+                                               void *param);
+
+extern _X_EXPORT void mieqRemoveCallbackOnDrained(CallbackProcPtr callback,
+                                                  void *param);
+
 extern DeviceIntPtr CopyGetMasterEvent(DeviceIntPtr /* sdev */ ,
                                        InternalEvent * /* original */ ,
                                        InternalEvent *  /* copy */
diff --git a/mi/mieq.c b/mi/mieq.c
index 09b71b639..bcd62d572 100644
--- a/mi/mieq.c
+++ b/mi/mieq.c
@@ -87,6 +87,8 @@ typedef struct _EventQueue {
 
 static EventQueueRec miEventQueue;
 
+static CallbackListPtr miCallbacksWhenDrained = NULL;
+
 static size_t
 mieqNumEnqueued(EventQueuePtr eventQueue)
 {
@@ -565,5 +567,21 @@ mieqProcessInputEvents(void)
 
     inProcessInputEvents = FALSE;
 
+    CallCallbacks(&miCallbacksWhenDrained, NULL);
+
+    input_unlock();
+}
+
+void mieqAddCallbackOnDrained(CallbackProcPtr callback, void *param)
+{
+    input_lock();
+    AddCallback(&miCallbacksWhenDrained, callback, param);
+    input_unlock();
+}
+
+void mieqRemoveCallbackOnDrained(CallbackProcPtr callback, void *param)
+{
+    input_lock();
+    DeleteCallback(&miCallbacksWhenDrained, callback, param);
     input_unlock();
 }