first phase of transition to unified Unicode build:

1. changed c_str() to return wxCStrData (implicitly convertible to wxChar*)
2. added template type-safe wrappers for vararg functions
3. added wxUniChar class representing single Unicode character
4. changed wxString::operator[] and wxString::iterator to return wxUniChar


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@44865 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/strvararg.cpp

@@ -0,0 +1,79 @@
+///////////////////////////////////////////////////////////////////////////////
+// Name:        src/common/strvararg.cpp
+// Purpose:     macros for implementing type-safe vararg passing of strings
+// Author:      Vaclav Slavik
+// Created:     2007-02-19
+// RCS-ID:      $Id$
+// Copyright:   (c) 2007 REA Elektronik GmbH
+// Licence:     wxWindows licence
+///////////////////////////////////////////////////////////////////////////////
+
+// ============================================================================
+// declarations
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------
+
+// for compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#ifdef __BORLANDC__
+    #pragma hdrstop
+#endif
+
+#include "wx/strvararg.h"
+#include "wx/buffer.h"
+#include "wx/strconv.h"
+#include "wx/string.h"
+
+// ============================================================================
+// implementation
+// ============================================================================
+
+const wxArgNativeCharType *wxArgNormalizer<const wxCStrData&>::get() const
+{
+    return m_value;
+}
+
+const wxArgNativeCharType *wxArgNormalizer<const wxString&>::get() const
+{
+    return m_value.c_str();
+}
+
+#if wxUSE_UNICODE_WCHAR
+
+wxArgNormalizer<const char*>::wxArgNormalizer(const char *value)
+{
+    m_value = new wxWCharBuffer(wxConvLibc.cMB2WC(value));
+}
+
+wxArgNormalizer<const char*>::~wxArgNormalizer()
+{
+    delete m_value;
+}
+
+const wchar_t *wxArgNormalizer<const char*>::get() const
+{
+    return m_value->data();
+}
+
+#elif wxUSE_WCHAR_T // !wxUSE_UNICODE_WCHAR && wxUSE_WCHAR_T
+
+wxArgNormalizer<const wchar_t*>::wxArgNormalizer(const wchar_t *value)
+{
+    m_value = new wxCharBuffer(wxConvLibc.cWC2MB(value));
+}
+
+wxArgNormalizer<const wchar_t*>::~wxArgNormalizer()
+{
+    delete m_value;
+}
+
+const char *wxArgNormalizer<const wchar_t*>::get() const
+{
+    return m_value->data();
+}
+
+#endif // wxUSE_UNICODE_WCHAR / !wxUSE_UNICODE_WCHAR && wxUSE_WCHAR_T