LOK: don't crash when trying to show a dialog during file load

Opening an ODP with a linked object, which wants to show a "update
links?" dialog during the load, would assert in Online debug build
with this stack:

libvcllo.so!vcl::Window::SetLOKNotifier(vcl::Window * const this, const vcl::ILibreOfficeKitNotifier * pNotifier, bool bParent) Line 3188
libvcllo.so!Dialog::ImplStartExecute(Dialog * const this) Line 940
libvcllo.so!Dialog::Execute(Dialog * const this) Line 1072
libvcllo.so!SalInstanceDialog::run(SalInstanceDialog * const this) Line 1881
libvcllo.so!JSMessageDialog::run(JSMessageDialog * const this) Line 1483
libsfxlo.so!sfx2::LinkManager::UpdateAllLinks(sfx2::LinkManager * const this, bool bAskUpdate, bool bUpdateGrfLinks, weld::Window * pParentWin) Line 333
libsdlo.so!SdDrawDocument::UpdateAllLinks(SdDrawDocument * const this) Line 827
libsdlo.so!SdXMLFilter::Import(SdXMLFilter * const this, ErrCode & nError) Line 647
libsdlo.so!sd::DrawDocShell::Load(sd::DrawDocShell * const this, SfxMedium & rMedium) Line 299
libsfxlo.so!SfxObjectShell::LoadOwnFormat(SfxObjectShell * const this, SfxMedium & rMedium) Line 3320
libsfxlo.so!SfxObjectShell::DoLoad(SfxObjectShell * const this, SfxMedium * pMed) Line 705
libsfxlo.so!SfxBaseModel::load(SfxBaseModel * const this, const com::sun::star::uno::Sequence<com::sun::star::beans::PropertyValue> & seqArguments) Line 1983
libsfxlo.so!(anonymous namespace)::SfxFrameLoader_Impl::load((anonymous namespace)::SfxFrameLoader_Impl * const this, const com::sun::star::uno::Sequence<com::sun::star::beans::PropertyValue> & rArgs, const com::sun::star::uno::Reference<com::sun::star::frame::XFrame> & _rTargetFrame) Line 725
libfwklo.so!framework::LoadEnv::impl_loadContent(framework::LoadEnv * const this) Line 1176
libfwklo.so!framework::LoadEnv::start(framework::LoadEnv * const this) Line 412
libfwklo.so!framework::LoadEnv::startLoading(framework::LoadEnv * const this, const rtl::OUString & sURL, const com::sun::star::uno::Sequence<com::sun::star::beans::PropertyValue> & lMediaDescriptor, const com::sun::star::uno::Reference<com::sun::star::frame::XFrame> & xBaseFrame, const rtl::OUString & sTarget, sal_Int32 nSearchFlags, LoadEnvFeatures eFeature) Line 308
libfwklo.so!framework::LoadEnv::loadComponentFromURL(const com::sun::star::uno::Reference<com::sun::star::frame::XComponentLoader> & xLoader, const com::sun::star::uno::Reference<com::sun::star::uno::XComponentContext> & xContext, const rtl::OUString & sURL, const rtl::OUString & sTarget, sal_Int32 nSearchFlags, const com::sun::star::uno::Sequence<com::sun::star::beans::PropertyValue> & lArgs) Line 168
libfwklo.so!framework::Desktop::loadComponentFromURL(framework::Desktop * const this, const rtl::OUString & sURL, const rtl::OUString & sTargetFrameName, sal_Int32 nSearchFlags, const com::sun::star::uno::Sequence<com::sun::star::beans::PropertyValue> & lArguments) Line 592
libsofficeapp.so!lo_documentLoadWithOptions(LibreOfficeKit * pThis, const char * pURL, const char * pOptions) Line 2927
lok::Office::documentLoad(lok::Office * const this, const char * pFilterOptions, const char * pUrl) Line 981
Document::load(Document * const this, const std::shared_ptr<ChildSession> & session, const std::string & renderOpts) Line 1927
Document::onLoad(Document * const this, const std::string & sessionId, const std::string & uriAnonym, const std::string & renderOpts) Line 1224
ChildSession::loadDocument(ChildSession * const this,  tokens) Line 932
ChildSession::_handleInput(ChildSession * const this, const char * buffer, int length) Line 310
Session::handleMessage(Session * const this, const std::vector<char, std::allocator<char> > & data) Line 311
Document::forwardToChild(Document * const this,  prefix,  payload) Line 2139
Document::drainQueue(Document * const this) Line 238
KitSocketPoll::drainQueue(KitSocketPoll * const this) Line 2794
KitSocketPoll::kitPoll(KitSocketPoll * const this, int timeoutMicroS) Line 2873
libvcllo.so!SvpSalInstance::ImplYield(SvpSalInstance * const this, bool bWait, bool bHandleAllCurrentEvents) Line 434
libvcllo.so!SvpSalInstance::DoYield(SvpSalInstance * const this, bool bWait, bool bHandleAllCurrentEvents) Line 475
libvcllo.so!ImplYield(bool i_bWait, bool i_bAllEvents) Line 396
libvcllo.so!Application::Yield() Line 480
libvcllo.so!Application::Execute() Line 374
libsofficeapp.so!desktop::Desktop::Main(desktop::Desktop * const this) Line 1605
libvcllo.so!ImplSVMain() Line 229
libvcllo.so!SVMain() Line 261
libsofficeapp.so!soffice_main() Line 94
libsofficeapp.so!lo_runLoop(LibreOfficeKitPollCallback pPollCallback, LibreOfficeKitWakeCallback pWakeCallback, void * pData) Line 7846
lok::Office::runLoop(void * pData, LibreOfficeKitWakeCallback pWakeCallback, LibreOfficeKitPollCallback pPollCallback) Line 1135
lokit_main(const std::string & childRoot, const std::string & jailId, const std::string & sysTemplate, const std::string & loTemplate, bool noCapabilities, bool noSeccomp, bool useMountNamespaces, bool queryVersion, bool displayVersion, bool sysTemplateIncomplete, std::size_t numericIdentifier) Line 3691
createLibreOfficeKit(const std::string & childRoot, const std::string & sysTemplate,  loTemplate, bool useMountNamespaces, bool queryVersion) Line 490
forkit_main(int argc, char ** argv) Line 872

Change-Id: I45c20ed8c46e927301aa1de43179638a17608a26
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/179430
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>

1 files changed, 16 insertions, 12 deletions

diff --git a/vcl/source/window/dialog.cxx b/vcl/source/window/dialog.cxx
index 17f9ddc9fd48..8b33aa64c8db 100644
--- a/vcl/source/window/dialog.cxx
+++ b/vcl/source/window/dialog.cxx
@@ -925,18 +925,22 @@ bool Dialog::ImplStartExecute()
     {
         if (bKitActive && !GetLOKNotifier())
         {
-#ifdef IOS
-            // gh#5908 handle pasting disallowed clipboard contents on iOS
-            // When another app owns the current clipboard contents, pasting
-            // will display a "allow or disallow" dialog. If the disallow
-            // option is selected, the data from the UIPasteboard will be
-            // garbage and we will find ourselves here. Since calling
-            // SetLOKNotifier() with a nullptr aborts in an assert(), fix
-            // the crash by failing gracefully.
-            return false;
-#else
-            SetLOKNotifier(mpDialogImpl->m_aInstallLOKNotifierHdl.Call(nullptr));
-#endif
+            if (auto pNotifier = mpDialogImpl->m_aInstallLOKNotifierHdl.Call(nullptr))
+                SetLOKNotifier(pNotifier);
+            else
+            {
+                // gh#5908 handle pasting disallowed clipboard contents on iOS
+                // When another app owns the current clipboard contents, pasting
+                // will display a "allow or disallow" dialog. If the disallow
+                // option is selected, the data from the UIPasteboard will be
+                // garbage and we will find ourselves here. Since calling
+                // SetLOKNotifier() with a nullptr aborts in an assert(), fix
+                // the crash by failing gracefully.
+
+                // Also pNotifier may be nullptr when a dialog (e.g., "update
+                // links?") is to be shown when loading a document.
+                return false;
+            }
         }
 
         switch ( Application::GetDialogCancelMode() )