[PATCH] user32: Allow WM_CAPTURECHANGE indicating SetCapture() parameter.

[Christopher Thielen]

Fixes https://bugs.winehq.org/show_bug.cgi?id=13683

A window may be notified with WM_CAPTURECHANGED about itself
gaining mouse capture if it calls SetCapture() twice.

Tested on Windows XP and Fedora Workstation 22.

Signed-off-by: Christopher Thielen <cthielen at gmail.com>
---
  dlls/user32/input.c     |  2 +-
  dlls/user32/tests/msg.c | 30 ++++++++++++++++++++++++++++++
  2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/dlls/user32/input.c b/dlls/user32/input.c
index 40e35a9..63fae67 100644
--- a/dlls/user32/input.c
+++ b/dlls/user32/input.c
@@ -108,7 +108,7 @@ BOOL set_capture_window( HWND hwnd, UINT gui_flags, 
HWND *prev_ret )
      {
          USER_Driver->pSetCapture( hwnd, gui_flags );
  -        if (previous && previous != hwnd)
+        if (previous)
              SendMessageW( previous, WM_CAPTURECHANGED, 0, (LPARAM)hwnd );
           if (prev_ret) *prev_ret = previous;
diff --git a/dlls/user32/tests/msg.c b/dlls/user32/tests/msg.c
index d92fbc7..8ac3239 100644
--- a/dlls/user32/tests/msg.c
+++ b/dlls/user32/tests/msg.c
@@ -14906,6 +14906,35 @@ else
      flush_sequence();
  }
  +// Not const in order to set lParam during test
+static struct message DoubleSetCaptureSeq[] =
+{
+    { WM_CAPTURECHANGED, sent|wparam|lparam, 0, 1 },
+    { 0 }
+};
+
+static void test_DoubleSetCapture(void)
+{
+    HWND hwnd;
+
+    hwnd = CreateWindowExA(0, "TestWindowClass", "Test DoubleSetCapture",
+                           WS_OVERLAPPEDWINDOW | WS_VISIBLE,
+                           100, 100, 200, 200, 0, 0, 0, NULL);
+    ok (hwnd != 0, "Failed to create overlapped window\n");
+    DoubleSetCaptureSeq[0].lParam = (LPARAM)hwnd;
+    ShowWindow( hwnd, SW_SHOW );
+    flush_sequence();
+
+    trace("SetCapture( hwnd )\n");
+    SetCapture( hwnd );
+    trace("SetCapture( hwnd )\n");
+    SetCapture( hwnd );
+    ok_sequence(DoubleSetCaptureSeq, "SetCapture( hwnd ) twice", FALSE);
+    trace("done\n");
+
+    DestroyWindow(hwnd);
+}
+
  static void init_funcs(void)
  {
      HMODULE hKernel32 = GetModuleHandleA("kernel32.dll");
@@ -15045,6 +15074,7 @@ START_TEST(msg)
      test_layered_window();
      test_TrackPopupMenu();
      test_TrackPopupMenuEmpty();
+    test_DoubleSetCapture();
      /* keep it the last test, under Windows it tends to break the tests
       * which rely on active/foreground windows being correct.
       */
-- 
2.4.3