Andrew Nguyen : winmm: mixerOpen should return success with NULL dwCallback and CALLBACK_WINDOW flag .

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 0135bf8a0cfa61493de97ad3cc4c5e8844979348
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=0135bf8a0cfa61493de97ad3cc4c5e8844979348

Author: Andrew Nguyen <arethusa26 at gmail.com>
Date:   Sun Dec 21 01:48:40 2008 -0600

winmm: mixerOpen should return success with NULL dwCallback and CALLBACK_WINDOW flag.

---

 dlls/winmm/tests/mixer.c |    1 -
 dlls/winmm/winmm.c       |    2 +-
 2 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/dlls/winmm/tests/mixer.c b/dlls/winmm/tests/mixer.c
index d4227b4..6951621 100644
--- a/dlls/winmm/tests/mixer.c
+++ b/dlls/winmm/tests/mixer.c
@@ -1035,7 +1035,6 @@ static void test_mixerOpen()
 
         /* Test mixerOpen with a NULL dwCallback and CALLBACK_WINDOW flag. */
         rc = mixerOpen(&mix, d, 0, 0, CALLBACK_WINDOW);
-        todo_wine
         ok(rc == MMSYSERR_NOERROR,
            "mixerOpen: MMSYSERR_NOERROR expected, got %s\n",
            mmsys_error(rc));
diff --git a/dlls/winmm/winmm.c b/dlls/winmm/winmm.c
index 389fff8..d9bd190 100644
--- a/dlls/winmm/winmm.c
+++ b/dlls/winmm/winmm.c
@@ -355,7 +355,7 @@ UINT  MIXER_Open(LPHMIXER lphMix, UINT uDeviceID, DWORD_PTR dwCallback,
 
     case CALLBACK_WINDOW:
         mod.dwInstance = dwCallback;
-        if (!IsWindow((HWND)dwCallback))
+        if (dwCallback && !IsWindow((HWND)dwCallback))
             return MMSYSERR_INVALPARAM;
         break;
     }