When ole has set the clipboard data, the clipboard manager may preempt
this data (by sending a WM_RENDERFORMAT message). At this point the
clipboard ownership may be occupied by the clipboard manager; resulting
in a failure to flush the ole clipboard.

Signed-off-by: Haoyang Chen
---
dlls/ole32/clipboard.c | 2 ++
dlls/ole32/tests/clipboard.c | 10 ++++++++++
2 files changed, 12 insertions(+)

diff --git a/dlls/ole32/clipboard.c b/dlls/ole32/clipboard.c
index e61b3076883..ebc498d52e7 100644
--- a/dlls/ole32/clipboard.c
+++ b/dlls/ole32/clipboard.c
@@ -2261,6 +2261,7 @@ HRESULT WINAPI OleFlushClipboard(void)
HRESULT hr;
ole_clipbrd *clipbrd;
HWND wnd;
+ MSG msg;

TRACE("() ");

@@ -2273,6 +2274,7 @@ HRESULT WINAPI OleFlushClipboard(void)
*/
if (!clipbrd->src_data) return S_OK;

+ PeekMessageW(&msg, wnd, WM_RENDERFORMAT, WM_RENDERFORMAT, PM_REMOVE);
if (!OpenClipboard(wnd)) return CLIPBRD_E_CANT_OPEN;

SendMessageW(wnd, WM_RENDERALLFORMATS, 0, 0);
diff --git a/dlls/ole32/tests/clipboard.c b/dlls/ole32/tests/clipboard.c
index fd8f287680b..47700e7f3fd 100644
--- a/dlls/ole32/tests/clipboard.c
+++ b/dlls/ole32/tests/clipboard.c
@@ -1085,6 +1085,7 @@ static void test_set_clipboard_DRAWCLIPBOARD(void)
HWND viewer;
int ret;
HANDLE thread;
+ int i;

hr = DataObjectImpl_CreateText("data", &data);
ok(hr == S_OK, "Failed to create data object: 0x%08x ", hr);
@@ -1120,6 +1121,15 @@ static void test_set_clipboard_DRAWCLIPBOARD(void)
ret = SendMessageA( viewer, WM_USER, 0, 0 );
ok( ret == 2, "%u WM_DRAWCLIPBOARD received ", ret );

+ Sleep(500);
+
+ for (i = 0; i < 10; i++)
+ {
+ hr = OleFlushClipboard();
+ if (hr == S_OK) break;
+ Sleep(100);
+ }
+ ok(hr == S_OK, "got %08x ", hr);
clip_data = NULL;
hr = OleFlushClipboard();
ok(hr == S_OK, "failed to flush clipboard, hr = 0x%08x ", hr);
--
2.20.1