[PATCH 1/1] mf/session: Ensure that the command callback does not return without clearing SESSION_FLAG_PENDING_COMMAND.

[Torge Matthies]

From: Torge Matthies

Leaving SESSION_FLAG_PENDING_COMMAND set results in no more work items being queued by session_submit_command, and even
if they were, callback would return immediately due to a check at the start of the function.
Thus, it is never valid to leave the function without clearing the SESSION_FLAG_PENDING_COMMAND flag.

This case can be hit by SESSION_CMD_START, and leaves the session unable to process any commands.

Fix this by ensuring that SESSION_FLAG_PENDING_COMMAND is always cleared before the command callback returns.
---
 dlls/mf/session.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/dlls/mf/session.c b/dlls/mf/session.c
index 3c989249229..da8e0bb824a 100644
--- a/dlls/mf/session.c
+++ b/dlls/mf/session.c
@@ -2725,7 +2725,6 @@ static HRESULT WINAPI session_commands_callback_Invoke(IMFAsyncCallback *iface,
             break;
         case SESSION_CMD_SET_TOPOLOGY:
             session_set_topology(session, op->set_topology.flags, op->set_topology.topology);
-            session_command_complete(session);
             break;
         case SESSION_CMD_START:
             session_start(session, &op->start.time_format, &op->start.start_position);
@@ -2744,12 +2743,14 @@ static HRESULT WINAPI session_commands_callback_Invoke(IMFAsyncCallback *iface,
             break;
         case SESSION_CMD_SHUTDOWN:
             session_clear_command_list(session);
-            session_command_complete(session);
             break;
         default:
             ;
     }

+    if (session->presentation.flags & SESSION_FLAG_PENDING_COMMAND)
+        session_command_complete(session);
+
     LeaveCriticalSection(&session->cs);

IUnknown_Release(&op->IUnknown_iface);