Avoid division by zero

...as happens during CppunitTest_sd_export_tests:

> sd/source/filter/eppt/epptso.cxx:118:76: runtime error: division by zero
>  #0 in PPTExBulletProvider::GetId(Graphic const&, Size&) at sd/source/filter/eppt/epptso.cxx:118:76 (instdir/program/libsdfiltlo.so +0x38e7e7)
>  #1 in ParagraphObj::ImplGetNumberingLevel(PPTExBulletProvider*, short, bool, bool) at sd/source/filter/eppt/pptx-text.cxx:897:46 (instdir/program/libsdfiltlo.so +0x55464d)
>  #2 in ParagraphObj::ImplGetParagraphValues(PPTExBulletProvider*, bool) at sd/source/filter/eppt/pptx-text.cxx:1114:5 (instdir/program/libsdfiltlo.so +0x54c01d)
>  #3 in ParagraphObj::ParagraphObj(com::sun::star::uno::Reference<com::sun::star::text::XTextContent> const&, ParaFlags, FontCollection&, PPTExBulletProvider&) at sd/source/filter/eppt/pptx-text.cxx:741:9 (instdir/program/libsdfiltlo.so +0x54e373)
>  #4 in TextObj::TextObj(com::sun::star::uno::Reference<com::sun::star::text::XSimpleText> const&, int, FontCollection&, PPTExBulletProvider&) at sd/source/filter/eppt/pptx-text.cxx:1313:47 (instdir/program/libsdfiltlo.so +0x5574a4)
>  #5 in TextObjBinary::TextObjBinary(com::sun::star::uno::Reference<com::sun::star::text::XSimpleText> const&, int, FontCollection&, PPTExBulletProvider&) at sd/source/filter/eppt/eppt.hxx:141:101 (instdir/program/libsdfiltlo.so +0x4068e7)
>  #6 in PPTWriter::ImplWritePage(PHLayout const&, EscherSolverContainer&, PageType, bool, int) at sd/source/filter/eppt/epptso.cxx:2367:39 (instdir/program/libsdfiltlo.so +0x3dc5bb)
>  #7 in PPTWriter::ImplWriteSlide(unsigned int, unsigned int, unsigned short, bool, com::sun::star::uno::Reference<com::sun::star::beans::XPropertySet> const&) at sd/source/filter/eppt/eppt.cxx:312:5 (instdir/program/libsdfiltlo.so +0x327239)
>  #8 in PPTWriterBase::CreateSlide(unsigned int) at sd/source/filter/eppt/pptx-epptbase.cxx:399:5 (instdir/program/libsdfiltlo.so +0x49896a)
>  #9 in PPTWriterBase::exportPPT(std::__debug::vector<com::sun::star::beans::PropertyValue, std::allocator<com::sun::star::beans::PropertyValue> > const&) at sd/source/filter/eppt/pptx-epptbase.cxx:233:15 (instdir/program/libsdfiltlo.so +0x48ff5e)
>  #10 in ExportPPT at sd/source/filter/eppt/eppt.cxx:1451:17 (instdir/program/libsdfiltlo.so +0x34dfdc)
>  #11 in SdPPTFilter::Export() at sd/source/filter/sdpptwrp.cxx:173:24 (instdir/program/libsdlo.so +0x26b070d)
>  #12 in sd::DrawDocShell::ConvertTo(SfxMedium&) at sd/source/ui/docshell/docshel4.cxx:662:29 (instdir/program/libsdlo.so +0x2c454b7)
>  #13 in SfxObjectShell::SaveTo_Impl(SfxMedium&, SfxItemSet const*) at sfx2/source/doc/objstor.cxx:1508:19 (instdir/program/libsfxlo.so +0x2baa19d)
>  #14 in SfxObjectShell::PreDoSaveAs_Impl(rtl::OUString const&, rtl::OUString const&, SfxItemSet const&) at sfx2/source/doc/objstor.cxx:2792:39 (instdir/program/libsfxlo.so +0x2bcdc17)
>  #15 in SfxObjectShell::CommonSaveAs_Impl(INetURLObject const&, rtl::OUString const&, SfxItemSet&) at sfx2/source/doc/objstor.cxx:2650:9 (instdir/program/libsfxlo.so +0x2bc86cf)
>  #16 in SfxObjectShell::APISaveAs_Impl(rtl::OUString const&, SfxItemSet&) at sfx2/source/doc/objserv.cxx:302:19 (instdir/program/libsfxlo.so +0x2b69519)
>  #17 in SfxBaseModel::impl_store(rtl::OUString const&, com::sun::star::uno::Sequence<com::sun::star::beans::PropertyValue> const&, bool) at sfx2/source/doc/sfxbasemodel.cxx:2959:46 (instdir/program/libsfxlo.so +0x2cbd740)
>  #18 in SfxBaseModel::storeToURL(rtl::OUString const&, com::sun::star::uno::Sequence<com::sun::star::beans::PropertyValue> const&) at sfx2/source/doc/sfxbasemodel.cxx:1638:13 (instdir/program/libsfxlo.so +0x2cc26b5)
>  #19 in SdExportTest::testBulletsAsImage() at sd/qa/unit/export-tests.cxx:934:20 (workdir/LinkTarget/CppunitTest/libtest_sd_export_tests.so +0x8988c)

Change-Id: I516bb2367d6a7fae23e2d474e63ab50af925208b
Reviewed-on: https://gerrit.libreoffice.org/54034
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

1 files changed, 31 insertions, 16 deletions

diff --git a/sd/source/filter/eppt/epptso.cxx b/sd/source/filter/eppt/epptso.cxx
index 7ca401b50dff..d3a017236c72 100644
--- a/sd/source/filter/eppt/epptso.cxx
+++ b/sd/source/filter/eppt/epptso.cxx
@@ -115,26 +115,41 @@ sal_uInt16 PPTExBulletProvider::GetId(Graphic const & rGraphic, Size& rGraphicSi
 
         if ( rGraphicSize.Width() && rGraphicSize.Height() )
         {
-            double          fQ1 = ( static_cast<double>(aPrefSize.Width()) / static_cast<double>(aPrefSize.Height()) );
-            double          fQ2 = ( static_cast<double>(rGraphicSize.Width()) / static_cast<double>(rGraphicSize.Height()) );
-            double          fXScale = 1;
-            double          fYScale = 1;
+            Size aNewSize;
+            bool changed = false;
+            if (aPrefSize.Width() == 0 || aPrefSize.Height() == 0)
+            {
+                aBmpEx.Scale(aPrefSize);
+                aNewSize = aPrefSize;
+                changed = true;
+            }
+            else
+            {
+                double          fQ1 = ( static_cast<double>(aPrefSize.Width()) / static_cast<double>(aPrefSize.Height()) );
+                double          fQ2 = ( static_cast<double>(rGraphicSize.Width()) / static_cast<double>(rGraphicSize.Height()) );
+                double          fXScale = 1;
+                double          fYScale = 1;
 
-            if ( fQ1 > fQ2 )
-                fYScale = fQ1 / fQ2;
-            else if ( fQ1 < fQ2 )
-                fXScale = fQ2 / fQ1;
+                if ( fQ1 > fQ2 )
+                    fYScale = fQ1 / fQ2;
+                else if ( fQ1 < fQ2 )
+                    fXScale = fQ2 / fQ1;
 
-            if ( ( fXScale != 1.0 ) || ( fYScale != 1.0 ) )
-            {
-                aBmpEx.Scale( fXScale, fYScale );
-                Size aNewSize( static_cast<sal_Int32>(static_cast<double>(rGraphicSize.Width()) / fXScale + 0.5 ),
-                                static_cast<sal_Int32>(static_cast<double>(rGraphicSize.Height()) / fYScale + 0.5 ) );
+                if ( ( fXScale != 1.0 ) || ( fYScale != 1.0 ) )
+                {
+                    aBmpEx.Scale( fXScale, fYScale );
+                    aNewSize = Size( static_cast<sal_Int32>(static_cast<double>(rGraphicSize.Width()) / fXScale + 0.5 ),
+                                     static_cast<sal_Int32>(static_cast<double>(rGraphicSize.Height()) / fYScale + 0.5 ) );
+                    changed = true;
+                }
 
-                rGraphicSize = aNewSize;
+                if (changed)
+                {
+                    rGraphicSize = aNewSize;
 
-                aMappedGraphic = Graphic( aBmpEx );
-                xGraphicObject.reset(new GraphicObject(aMappedGraphic));
+                    aMappedGraphic = Graphic( aBmpEx );
+                    xGraphicObject.reset(new GraphicObject(aMappedGraphic));
+                }
             }
         }
         sal_uInt32 nId = pGraphicProv->GetBlibID(aBuExPictureStream, *xGraphicObject.get());