tdf#108189 inspection of object hangs LO

There is no general solution to this that I am aware of, so just
implement a rather specific solution that will need periodic extending
to check for other dangerous properties

Change-Id: Ie09d89416fea5b7cdf782319ed9921657faa5a5a
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/176593
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

5 files changed, 40 insertions, 2 deletions

diff --git a/basctl/inc/strings.hrc b/basctl/inc/strings.hrc
index ee83fbb543b0..8dba3f960c93 100644
--- a/basctl/inc/strings.hrc
+++ b/basctl/inc/strings.hrc
@@ -114,6 +114,7 @@
 #define RID_STR_MODULE_READONLY             NC_("RID_STR_READONLY_WARNING", "This module is read-only and cannot be edited.")
 #define RID_STR_DIALOG_READONLY             NC_("RID_STR_READONLY_WARNING", "This dialog is read-only and cannot be edited.")
 #define RID_LINE_STATUS_CONTROL             NC_("RID_LINE_STATUS_CONTROL", "Current line and character. Click to open 'Go to Line' dialog.")
+#define RID_VARIABLE_TOO_LARGE_TO_DISPLAY   NC_("RID_VARIABLE_TOO_LARGE_TO_DISPLAY", "Variable too large to display in debugger")
 
 // Color scheme names
 #define RID_STR_COLORSCHEME_DEFAULT         NC_("RID_STR_COLORSCHEME_DEFAULT", "Default")
diff --git a/basctl/source/basicide/baside2b.cxx b/basctl/source/basicide/baside2b.cxx
index b3d44695740c..b7b75b958183 100644
--- a/basctl/source/basicide/baside2b.cxx
+++ b/basctl/source/basicide/baside2b.cxx
@@ -2314,7 +2314,13 @@ SbxBase* WatchWindow::ImplGetSBXForEntry(const weld::TreeIter& rEntry, bool& rbA
                 // Force getting value
                 SbxValues aRes;
                 aRes.eType = SbxVOID;
-                pVar->Get( aRes );
+                if (!isVeryLargeUnoProperty(pVar))
+                    pVar->Get( aRes );
+                else
+                {
+                    aRes.eType = SbxSTRING;
+                    aRes.pOUString = new OUString("<" + IDEResId(RID_VARIABLE_TOO_LARGE_TO_DISPLAY) + ">");
+                }
             }
         }
         // Array?
@@ -2495,7 +2501,11 @@ void WatchWindow::UpdateWatches(bool bBasicStopped)
             {
                 // extra treatment of arrays
                 SbxDataType eType = pVar->GetType();
-                if ( eType & SbxARRAY )
+                if (isVeryLargeUnoProperty(pVar))
+                {
+                    aWatchStr += "<" + IDEResId(RID_VARIABLE_TOO_LARGE_TO_DISPLAY) + ">";
+                }
+                else if ( eType & SbxARRAY )
                 {
                     // consider multidimensional arrays!
                     if (SbxDimArray* pNewArray = dynamic_cast<SbxDimArray*>(pVar->GetObject()))
diff --git a/basic/source/classes/sbunoobj.cxx b/basic/source/classes/sbunoobj.cxx
index 7f75e18bbe5b..25a395e7a6bf 100644
--- a/basic/source/classes/sbunoobj.cxx
+++ b/basic/source/classes/sbunoobj.cxx
@@ -40,6 +40,7 @@
 #include <com/sun/star/script/ArrayWrapper.hpp>
 #include <com/sun/star/script/CannotConvertException.hpp>
 #include <com/sun/star/script/NativeObjectWrapper.hpp>
+#include <com/sun/star/sheet/XSheetCellCursor.hpp>
 
 #include <com/sun/star/uno/XComponentContext.hpp>
 #include <com/sun/star/uno/DeploymentException.hpp>
@@ -2585,6 +2586,27 @@ SbUnoProperty::SbUnoProperty
 SbUnoProperty::~SbUnoProperty()
 {}
 
+bool isVeryLargeUnoProperty(SbxVariable const * pVar)
+{
+    auto pUnoVar = dynamic_cast<const SbUnoProperty*>(pVar);
+    if (!pUnoVar)
+        return false;
+    // The ScCellRangeObj methods will attempt to generate massive strings,
+    // which will use up massive amounts of RAM and also lock of the program
+    // for some time.
+    const OUString & aUnoName = pUnoVar->getUnoName();
+    if (aUnoName == "DataArray" || aUnoName == "FormulaArray")
+    {
+        auto pParent = dynamic_cast<const SbUnoObject*>(pUnoVar->GetParent());
+        if (!pParent)
+            return false;
+        css::uno::Any aAny = const_cast<SbUnoObject*>(pParent)->getUnoAny();
+        css::uno::Reference<css::sheet::XSheetCellCursor> xCursor = aAny.query<css::sheet::XSheetCellCursor>();
+        if (xCursor)
+            return true;
+    }
+    return false;
+}
 
 SbxVariable* SbUnoObject::Find( const OUString& rName, SbxClassType t )
 {
diff --git a/basic/source/inc/sbunoobj.hxx b/basic/source/inc/sbunoobj.hxx
index 4dee669219ef..16e32af5a87e 100644
--- a/basic/source/inc/sbunoobj.hxx
+++ b/basic/source/inc/sbunoobj.hxx
@@ -200,6 +200,7 @@ public:
     bool isInvocationBased() const
         { return mbInvocation; }
     SbxDataType getRealType() const { return mRealType; }
+    const OUString& getUnoName() const { return aUnoProp.Name; }
 };
 
 // factory class to create uno-structs per DIM AS NEW
diff --git a/include/basic/sbuno.hxx b/include/basic/sbuno.hxx
index b19f0f5da249..cd35561db33a 100644
--- a/include/basic/sbuno.hxx
+++ b/include/basic/sbuno.hxx
@@ -41,4 +41,8 @@ css::uno::Any sbxToUnoValue( const SbxValue* pVar, const css::uno::Type& rType,
 
 BASIC_DLLPUBLIC void unoToSbxValue( SbxVariable* pVar, const css::uno::Any& aValue );
 
+/// Used by the BASIC debugger to detect very large UNO property values that should not be displayed
+/// because they will stall the program.
+BASIC_DLLPUBLIC bool isVeryLargeUnoProperty(const SbxVariable* pVar);
+
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */