1) Create new database (.odb file)
2) Create a macro in the database, e.g.:

Sub Tst()
    MsgBox "Tst"
End Tst()

3) Create a dialog in the database
4) save as e.g. foo.odb
5) exit LibreOffice
6) Launch LibreOffice
7) Open foo.odb
8) Run the macro; this forces the loading of the "Standard" Basic library of the .odb file. DO NOT load the Dialog library in any way.
9) Make a change to the database: e.g. create a new report.
10) "File/save" (or the equivalent toolbar button) does not do anything

If one either does not run any macro (not load the basic library) or loads the Dialog library, then the save works.

I traced this back to:

In dbaccess/source/core/dataaccess/ModelImpl.[hc]xx, m_xDialogLibraries is set (as a reference), but the library is NOT LOADED. On save:
 - ODatabaseDocument::store calls
 - ODatabaseDocument::impl_storeToStorage_throw calls
 - ODatabaseDocument::impl_writeStorage_throw calls
 - ODatabaseModelImpl::storeLibraryContainersTo has this code:

    if ( m_xDialogLibraries.is() )
        m_xDialogLibraries->storeLibrariesToStorage( _rxToRootStorage );

That is, it calls SfxDialogLibraryContainer::storeLibrariesToStorage (baisc/source/uno/dlgcont.cxx) as soon as m_xDialogLibraries is a valid reference. Then:

 - SfxDialogLibraryContainer::storeLibrariesToStorage iterates over the libraries
 - within a library (variable xLib) it iterates over the dialogs in that library:

            Sequence< OUString > sDialogs = xLib->getElementNames();
            sal_Int32 nDialogs( sDialogs.getLength() );
            for ( sal_Int32 j=0; j < nDialogs; ++j )
            {
                // Each Dialog has an associated xISP
                Reference< io::XInputStreamProvider > xISP;
                xLib->getByName( sDialogs[ j ] ) >>= xISP;


And here you have it: getByName is called on xLib, but xLib is not loaded. Meaning (in file basic/source/uno/namecont.cxx):

 - SfxLibraryContainer::getByName calls 
 - SfxLibrary::getByName

The first thing that SfxLibrary::getByName does is
   impl_checkLoaded();
which raises  WrappedTargetException (with an empty message!), because the library is not loaded.

I see three places where this can be "fixed" and I'm not sure which is the "right fix". Please advise.


1) Remove call to impl_checkLoaded() from SfxLibrary::getByName

Then it returns a NULL reference, and SfxDialogLibraryContainer::storeLibrariesToStorage handles that well:

                xLib->getByName( sDialogs[ j ] ) >>= xISP;
                if ( xISP.is() )

2) Add to SfxDialogLibraryContainer::storeLibrariesToStorage before the code above:

                if ( ! xLib->isLibraryLoaded(sDialogs[ j ]) ) {
                    continue;
                }

3) Change ODatabaseModelImpl::storeLibraryContainersTo from


    if ( m_xDialogLibraries.is() )
       m_xDialogLibraries->storeLibrariesToStorage( _rxToRootStorage );
 
to

    if ( m_xDialogLibraries.is() &&  m_xDialogLibraries->isModified() )
       m_xDialogLibraries->storeLibrariesToStorage( _rxToRootStorage );
 
And the same for m_xBasicLibraries, obviously.


Analysis:

I have a bad feeling about number "3)"; it corrects this specific bug, but it may still be the case that some Dialog libraries are modified and others are not loaded... and then we are in trouble again.

Number 1) essentially changes the guarantees given by getByName; it was guaranteed to return a valid Reference or throw an exception, and now it can return a NULL reference, which can break existing code. OTOH, if some other code somewhere _also_ calls getByName without _first_ checking whether the library is loaded (but properly checks whether it got a valid reference afterwards), it will also fix that yet undiscovered bug :)

Number 2) has the symmetric advantages and disadvantages of number 1)... It won't make previously valid code invalid (the guarantees given by getByName don't change), but it lets responsibility to check for isLibraryLoaded _before_ to callers of getByName, which is a recipe for future similar bugs IMHO.