[PATCH v2 2/3] win32u: Only return from NtWaitForMultipleObjects if signaled.

[Rémi Bernon]

From: Rémi Bernon

There's only driver events, with QS_DRIVER, internal hardware messages,
with QS_HARDWARE, or input hardware messages with QS_INPUT and we should
avoid returning from the wait unnecessarily.

Some applications like iTunes, simply call MsgWaitForMultipleObjects in
a loop with an empty mask and without processing any message. They don't
expect the wait to return spuriously more than a couple of times (which
is allowed and happens on windows when focus changes for instance).

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=58793
---
 dlls/win32u/message.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/dlls/win32u/message.c b/dlls/win32u/message.c
index 4b179619cf9..28a05ce1027 100644
--- a/dlls/win32u/message.c
+++ b/dlls/win32u/message.c
@@ -3229,8 +3229,7 @@ BOOL process_driver_events( UINT mask )
         peek_message( &msg, &filter );
     }

-    /* check for hardware messages requiring client dispatch */
-    return check_internal_bits( QS_HARDWARE );
+    return is_queue_signaled();
 }

void check_for_events( UINT flags )
@@ -3287,12 +3286,9 @@ static DWORD wait_message( DWORD count, const HANDLE *handles, DWORD timeout, DW
         params.restore = TRUE;
     }

-    if (process_driver_events( QS_ALLINPUT )) ret = count - 1;
-    else
-    {
-        do ret = NtWaitForMultipleObjects( count, handles, !(flags & MWMO_WAITALL), !!(flags & MWMO_ALERTABLE), abs );
-        while (ret == count - 1 && !process_driver_events( QS_ALLINPUT ) && !is_queue_signaled());
-    }
+    process_driver_events( QS_ALLINPUT );
+    do ret = NtWaitForMultipleObjects( count, handles, !(flags & MWMO_WAITALL), !!(flags & MWMO_ALERTABLE), abs );
+    while (ret == count - 1 && !process_driver_events( QS_ALLINPUT ));
     if (HIWORD(ret)) /* is it an error code? */
     {
         RtlSetLastWin32Error( RtlNtStatusToDosError(ret) );