From ce37290a5a7b630207c4303c90c44a9a09a8ab2b Mon Sep 17 00:00:00 2001
From: Nikolay Sivov <nsivov@codeweavers.com>
Date: Wed, 14 Apr 2021 09:49:10 +0300
Subject: [PATCH] mfplat: Release queue subscriber on queue release.

Signed-off-by: Nikolay Sivov <nsivov@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>
---
 dlls/mfplat/main.c         |  6 ++----
 dlls/mfplat/tests/mfplat.c | 21 +++++++++++++++++++--
 2 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/dlls/mfplat/main.c b/dlls/mfplat/main.c
index e23c648c823..5a35350f5c5 100644
--- a/dlls/mfplat/main.c
+++ b/dlls/mfplat/main.c
@@ -7019,6 +7019,7 @@ static void event_queue_cleanup(struct event_queue *queue)
 
     while ((event = queue_pop_event(queue)))
         IMFMediaEvent_Release(event);
+    event_queue_clear_subscriber(queue);
 }
 
 static HRESULT WINAPI eventqueue_QueryInterface(IMFMediaEventQueue *iface, REFIID riid, void **out)
@@ -7162,9 +7163,7 @@ static HRESULT WINAPI eventqueue_EndGetEvent(IMFMediaEventQueue *iface, IMFAsync
     else if (queue->subscriber == (IRtwqAsyncResult *)result)
     {
         *event = queue_pop_event(queue);
-        if (queue->subscriber)
-            IRtwqAsyncResult_Release(queue->subscriber);
-        queue->subscriber = NULL;
+        event_queue_clear_subscriber(queue);
         queue->notified = FALSE;
         hr = *event ? S_OK : E_FAIL;
     }
@@ -7265,7 +7264,6 @@ static HRESULT WINAPI eventqueue_Shutdown(IMFMediaEventQueue *iface)
     if (!queue->is_shut_down)
     {
         event_queue_cleanup(queue);
-        event_queue_clear_subscriber(queue);
         queue->is_shut_down = TRUE;
     }
 
diff --git a/dlls/mfplat/tests/mfplat.c b/dlls/mfplat/tests/mfplat.c
index 603dbbe22ff..fd9a27d599c 100644
--- a/dlls/mfplat/tests/mfplat.c
+++ b/dlls/mfplat/tests/mfplat.c
@@ -326,6 +326,7 @@ static WCHAR *load_resource(const WCHAR *name)
 struct test_callback
 {
     IMFAsyncCallback IMFAsyncCallback_iface;
+    LONG refcount;
     HANDLE event;
     DWORD param;
     IMFMediaEvent *media_event;
@@ -352,12 +353,14 @@ static HRESULT WINAPI testcallback_QueryInterface(IMFAsyncCallback *iface, REFII
 
 static ULONG WINAPI testcallback_AddRef(IMFAsyncCallback *iface)
 {
-    return 2;
+    struct test_callback *callback = impl_from_IMFAsyncCallback(iface);
+    return InterlockedIncrement(&callback->refcount);
 }
 
 static ULONG WINAPI testcallback_Release(IMFAsyncCallback *iface)
 {
-    return 1;
+    struct test_callback *callback = impl_from_IMFAsyncCallback(iface);
+    return InterlockedDecrement(&callback->refcount);
 }
 
 static HRESULT WINAPI testcallback_GetParameters(IMFAsyncCallback *iface, DWORD *flags, DWORD *queue)
@@ -2462,6 +2465,7 @@ static void init_test_callback(struct test_callback *callback)
 {
     callback->IMFAsyncCallback_iface.lpVtbl = &testcallbackvtbl;
     callback->event = NULL;
+    callback->refcount = 1;
 }
 
 static void test_MFCreateAsyncResult(void)
@@ -3114,6 +3118,19 @@ static void test_event_queue(void)
 
     IMFMediaEventQueue_Release(queue);
 
+    /* Release while subscribed. */
+    init_test_callback(&callback);
+
+    hr = MFCreateEventQueue(&queue);
+    ok(hr == S_OK, "Failed to create event queue, hr %#x.\n", hr);
+
+    hr = IMFMediaEventQueue_BeginGetEvent(queue, &callback.IMFAsyncCallback_iface, NULL);
+    ok(hr == S_OK, "Failed to Begin*, hr %#x.\n", hr);
+    EXPECT_REF(&callback.IMFAsyncCallback_iface, 2);
+
+    IMFMediaEventQueue_Release(queue);
+    EXPECT_REF(&callback.IMFAsyncCallback_iface, 1);
+
     hr = MFShutdown();
     ok(hr == S_OK, "Failed to shut down, hr %#x.\n", hr);
 }