From 26b273bef910977bf0e770da58261e21e11f56ff Mon Sep 17 00:00:00 2001
From: Maarten Bent <MaartenBent@users.noreply.github.com>
Date: Sat, 10 Aug 2019 22:22:32 +0200
Subject: [PATCH] Fix RTTI class declarations of wxSVGFileDC

wxIMPLEMENT_DYNAMIC_CLASS requires a default constructor (no filename). Check
if m_outfile is initialized with a valid filename before using it.
---
 include/wx/dcsvg.h   |  9 +++++++++
 src/common/dcsvg.cpp | 18 +++++++++++++++---
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/include/wx/dcsvg.h b/include/wx/dcsvg.h
index 964e3166a9..4773c6152c 100644
--- a/include/wx/dcsvg.h
+++ b/include/wx/dcsvg.h
@@ -277,6 +277,7 @@ private:
     size_t m_clipUniqueId;
 
     wxDECLARE_ABSTRACT_CLASS(wxSVGFileDCImpl);
+    wxDECLARE_NO_COPY_CLASS(wxSVGFileDCImpl);
 };
 
 
@@ -298,6 +299,14 @@ public:
     void SetBitmapHandler(wxSVGBitmapHandler* handler);
 
     void SetShapeRenderingMode(wxSVGShapeRenderingMode renderingMode);
+
+private:
+    wxSVGFileDC()
+        : wxDC(new wxSVGFileDCImpl(this, wxString()))
+    {
+    }
+
+    wxDECLARE_DYNAMIC_CLASS(wxSVGFileDC);
 };
 
 #endif // wxUSE_SVG
diff --git a/src/common/dcsvg.cpp b/src/common/dcsvg.cpp
index 9d6b16b265..a02bbd6f5b 100644
--- a/src/common/dcsvg.cpp
+++ b/src/common/dcsvg.cpp
@@ -462,6 +462,8 @@ wxSVGBitmapFileHandler::ProcessBitmap(const wxBitmap& bmp,
 // wxSVGFileDC (specialisations)
 // ----------------------------------------------------------
 
+wxIMPLEMENT_DYNAMIC_CLASS(wxSVGFileDC, wxDC);
+
 void wxSVGFileDC::SetBitmapHandler(wxSVGBitmapHandler* handler)
 {
     ((wxSVGFileDCImpl*)GetImpl())->SetBitmapHandler(handler);
@@ -476,7 +478,7 @@ void wxSVGFileDC::SetShapeRenderingMode(wxSVGShapeRenderingMode renderingMode)
 // wxSVGFileDCImpl
 // ----------------------------------------------------------
 
-wxIMPLEMENT_ABSTRACT_CLASS(wxSVGFileDCImpl, wxDC);
+wxIMPLEMENT_ABSTRACT_CLASS(wxSVGFileDCImpl, wxDCImpl);
 
 wxSVGFileDCImpl::wxSVGFileDCImpl(wxSVGFileDC *owner, const wxString &filename,
                                  int width, int height, double dpi, const wxString &title)
@@ -517,7 +519,11 @@ void wxSVGFileDCImpl::Init(const wxString &filename, int Width, int Height,
     ////////////////////code here
 
     m_bmp_handler.reset();
-    m_outfile.reset(new wxFileOutputStream(m_filename));
+
+    if ( m_filename.IsEmpty() )
+        m_outfile.reset();
+    else
+        m_outfile.reset(new wxFileOutputStream(m_filename));
 
     wxString s;
     s += wxS("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n");
@@ -1215,14 +1221,20 @@ void wxSVGFileDCImpl::DoDrawBitmap(const class wxBitmap & bmp, wxCoord x, wxCoor
     if ( !m_bmp_handler )
         m_bmp_handler.reset(new wxSVGBitmapFileHandler(m_filename));
 
+    m_OK = m_outfile && m_outfile->IsOk();
+    if (!m_OK)
+        return;
+
     m_bmp_handler->ProcessBitmap(bmp, x, y, *m_outfile);
+    m_OK = m_outfile->IsOk();
 }
 
 void wxSVGFileDCImpl::write(const wxString &s)
 {
-    m_OK = m_outfile->IsOk();
+    m_OK = m_outfile && m_outfile->IsOk();
     if (!m_OK)
         return;
+
     const wxCharBuffer buf = s.utf8_str();
     m_outfile->Write(buf, strlen((const char *)buf));
     m_OK = m_outfile->IsOk();