Use the same console event loop in wxBase and wxCore in wxMSW.

Refactor the console event loop code into separate files to untangle it from
the GUI version and ensure that it doesn't depend on the GUI at all. It can
now be defined in the base library and simply reused by the core one.

This also makes the console event loop usable for other ports under Windows,
e.g. wxGTK.

Closes #14426.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72008 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/evtloopconsole.cpp

@@ -0,0 +1,161 @@
+///////////////////////////////////////////////////////////////////////////////
+// Name:        src/msw/evtloopconsole.cpp
+// Purpose:     wxConsoleEventLoop class for Windows
+// Author:      Vadim Zeitlin
+// Modified by:
+// Created:     01.06.01
+// RCS-ID:      $Id$
+// Copyright:   (c) 2001 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
+// Licence:     wxWindows licence
+///////////////////////////////////////////////////////////////////////////////
+
+// ============================================================================
+// declarations
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------
+
+// For compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#ifdef __BORLANDC__
+    #pragma hdrstop
+#endif
+
+#include "wx/evtloop.h"
+
+// ============================================================================
+// wxMSWEventLoopBase implementation
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// ctor/dtor
+// ----------------------------------------------------------------------------
+
+wxMSWEventLoopBase::wxMSWEventLoopBase()
+{
+    m_shouldExit = false;
+    m_exitcode = 0;
+}
+
+// ----------------------------------------------------------------------------
+// wxEventLoop message processing dispatching
+// ----------------------------------------------------------------------------
+
+bool wxMSWEventLoopBase::Pending() const
+{
+    MSG msg;
+    return ::PeekMessage(&msg, 0, 0, 0, PM_NOREMOVE) != 0;
+}
+
+bool wxMSWEventLoopBase::GetNextMessage(WXMSG* msg)
+{
+    const BOOL rc = ::GetMessage(msg, NULL, 0, 0);
+
+    if ( rc == 0 )
+    {
+        // got WM_QUIT
+        return false;
+    }
+
+    if ( rc == -1 )
+    {
+        // should never happen, but let's test for it nevertheless
+        wxLogLastError(wxT("GetMessage"));
+
+        // still break from the loop
+        return false;
+    }
+
+    return true;
+}
+
+int wxMSWEventLoopBase::GetNextMessageTimeout(WXMSG *msg, unsigned long timeout)
+{
+    // MsgWaitForMultipleObjects() won't notice any input which was already
+    // examined (e.g. using PeekMessage()) but not yet removed from the queue
+    // so we need to remove any immediately messages manually
+    //
+    // NB: using MsgWaitForMultipleObjectsEx() could simplify the code here but
+    //     it is not available in very old Windows versions
+    if ( !::PeekMessage(msg, 0, 0, 0, PM_REMOVE) )
+    {
+        // we use this function just in order to not block longer than the
+        // given timeout, so we don't pass any handles to it at all
+        DWORD rc = ::MsgWaitForMultipleObjects
+                     (
+                        0, NULL,
+                        FALSE,
+                        timeout,
+                        QS_ALLINPUT
+                     );
+
+        switch ( rc )
+        {
+            default:
+                wxLogDebug("unexpected MsgWaitForMultipleObjects() return "
+                           "value %lu", rc);
+                // fall through
+
+            case WAIT_TIMEOUT:
+                return -1;
+
+            case WAIT_OBJECT_0:
+                if ( !::PeekMessage(msg, 0, 0, 0, PM_REMOVE) )
+                {
+                    // somehow it may happen that MsgWaitForMultipleObjects()
+                    // returns true but there are no messages -- just treat it
+                    // the same as timeout then
+                    return -1;
+                }
+                break;
+        }
+    }
+
+    return msg->message != WM_QUIT;
+}
+
+// ============================================================================
+// wxConsoleEventLoop implementation
+// ============================================================================
+
+#if wxUSE_CONSOLE_EVENTLOOP
+
+void wxConsoleEventLoop::WakeUp()
+{
+#if wxUSE_THREADS
+    wxWakeUpMainThread();
+#endif
+}
+
+void wxConsoleEventLoop::ProcessMessage(WXMSG *msg)
+{
+    ::DispatchMessage(msg);
+}
+
+bool wxConsoleEventLoop::Dispatch()
+{
+    MSG msg;
+    if ( !GetNextMessage(&msg) )
+        return false;
+
+    ProcessMessage(&msg);
+
+    return !m_shouldExit;
+}
+
+int wxConsoleEventLoop::DispatchTimeout(unsigned long timeout)
+{
+    MSG msg;
+    int rc = GetNextMessageTimeout(&msg, timeout);
+    if ( rc != 1 )
+        return rc;
+
+    ProcessMessage(&msg);
+
+    return !m_shouldExit;
+}
+
+#endif // wxUSE_CONSOLE_EVENTLOOP