discard any pending messages for the socket being destroyed to avoid the problem with having them delivered to the next socket we create which reuses the same message number (patch 1856012)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@50893 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/changes.txt

@@ -299,6 +299,10 @@ All (GUI):
 
 - Added wxWindow::GetNextSibling() and GetPrevSibling()
 
+wxMSW:
+
+- Fix rare bug with messages delivered to wrong wxSocket (Tim Kosse)
+
 
 2.8.7
 -----

src/msw/gsockmsw.cpp

@@ -311,7 +311,19 @@ void GSocketMSWManager::Destroy_Socket(GSocket *socket)
   /* Remove the socket from the list */
   EnterCriticalSection(&critical);
   if ( socket->IsOk() )
-      socketList[(socket->m_msgnumber - WM_USER)] = NULL;
+  {
+      const int msgnum = socket->m_msgnumber;
+
+      // we need to remove any pending messages for this socket to avoid having
+      // them sent to a new socket which could reuse the same message number as
+      // soon as we destroy this one
+      MSG msg;
+      while ( ::PeekMessage(&msg, hWin, msgnum, msgnum, PM_REMOVE) )
+          ;
+
+      socketList[msgnum - WM_USER] = NULL;
+  }
+
   LeaveCriticalSection(&critical);
 }