svtools/source/misc/svtaccessiblefactory.cxx

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  30
  31 // MARKER(update_precomp.py): autogen include statement, do not remove
  32 #include "precompiled_svtools.hxx"
  33 #include "svtaccessiblefactory.hxx"
  34 #include <osl/module.h>
  35
  36 // #define UNLOAD_ON_LAST_CLIENT_DYING
  37     // this is not recommended currently. If enabled, the implementation will log
  38     // the number of active clients, and unload the acc library when the last client
  39     // goes away.
  40     // Sounds like a good idea, unfortunately, there's no guarantee that all objects
  41     // implemented in this library are already dead.
  42     // Iow, just because an object implementing an XAccessible (implemented in this lib
  43     // here) died, it's not said that everybody released all references to the
  44     // XAccessibleContext used by this component, and implemented in the acc lib.
  45     // So we cannot really unload the lib.
  46     //
  47     // Alternatively, if the lib would us own "usage counting", i.e. every component
  48     // implemented therein would affect a static ref count, the acc lib could care
  49     // for unloading itself.
  50
  51 //........................................................................
  52 namespace svt
  53 {
  54 //........................................................................
  55
  56     using namespace ::com::sun::star::uno;
  57     using namespace ::com::sun::star::awt;
  58     using namespace ::com::sun::star::accessibility;
  59
  60     namespace
  61     {
  62 #ifdef UNLOAD_ON_LAST_CLIENT_DYING
  63         static oslInterlockedCount                      s_nAccessibleFactoryAccesss = 0;
  64 #endif // UNLOAD_ON_LAST_CLIENT_DYING
  65         static oslModule                                s_hAccessibleImplementationModule = NULL;
  66         static GetSvtAccessibilityComponentFactory      s_pAccessibleFactoryFunc = NULL;
  67         static ::rtl::Reference< IAccessibleFactory >   s_pFactory;
  68
  69         //====================================================================
  70         //= AccessibleDummyFactory
  71         //====================================================================
  72         class AccessibleDummyFactory : public IAccessibleFactory
  73         {
  74         public:
  75             AccessibleDummyFactory();
  76
  77         protected:
  78             virtual ~AccessibleDummyFactory();
  79
  80         private:
  81             AccessibleDummyFactory( const AccessibleDummyFactory& );            // never implemented
  82             AccessibleDummyFactory& operator=( const AccessibleDummyFactory& ); // never implemented
  83
  84             oslInterlockedCount m_refCount;
  85
  86         public:
  87             // IReference
  88             virtual oslInterlockedCount SAL_CALL acquire();
  89             virtual oslInterlockedCount SAL_CALL release();
  90
  91             // IAccessibleFactory
  92             virtual IAccessibleTabListBox*
  93                 createAccessibleTabListBox(
  94                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*rxParent*/,
  95                     SvHeaderTabListBox& /*rBox*/
  96                 ) const
  97             {
  98                 return NULL;
  99             }
 100
 101             virtual IAccessibleBrowseBox*
 102                 createAccessibleBrowseBox(
 103                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_rxParent*/,
 104                     IAccessibleTableProvider& /*_rBrowseBox*/
 105                 ) const
 106             {
 107                 return NULL;
 108             }
 109
 110             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 111                 createAccessibleIconChoiceCtrl(
 112                     SvtIconChoiceCtrl& /*_rIconCtrl*/,
 113                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_xParent*/
 114                 ) const
 115             {
 116                 return NULL;
 117             }
 118
 119             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 120                 createAccessibleTabBar(
 121                     TabBar& /*_rTabBar*/
 122                 ) const
 123             {
 124                 return NULL;
 125             }
 126
 127             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >
 128                 createAccessibleTextWindowContext(
 129                     VCLXWindow* /*pVclXWindow*/, TextEngine& /*rEngine*/, TextView& /*rView*/, bool /*bCompoundControlChild*/
 130                 ) const
 131             {
 132                 return NULL;
 133             }
 134
 135             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 136                 createAccessibleTreeListBox(
 137                     SvTreeListBox& /*_rListBox*/,
 138                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_xParent*/
 139                 ) const
 140             {
 141                 return NULL;
 142             }
 143
 144             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 145                 createAccessibleBrowseBoxHeaderBar(
 146                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*rxParent*/,
 147                     IAccessibleTableProvider& /*_rOwningTable*/,
 148                     AccessibleBrowseBoxObjType /*_eObjType*/
 149                 ) const
 150             {
 151                 return NULL;
 152             }
 153
 154             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 155                 createAccessibleBrowseBoxTableCell(
 156                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_rxParent*/,
 157                     IAccessibleTableProvider& /*_rBrowseBox*/,
 158                     const ::com::sun::star::uno::Reference< ::com::sun::star::awt::XWindow >& /*_xFocusWindow*/,
 159                     sal_Int32 /*_nRowId*/,
 160                     sal_uInt16 /*_nColId*/,
 161                     sal_Int32 /*_nOffset*/
 162                 ) const
 163             {
 164                 return NULL;
 165             }
 166
 167             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 168                 createAccessibleBrowseBoxHeaderCell(
 169                     sal_Int32 /*_nColumnRowId*/,
 170                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*rxParent*/,
 171                     IAccessibleTableProvider& /*_rBrowseBox*/,
 172                     const ::com::sun::star::uno::Reference< ::com::sun::star::awt::XWindow >& /*_xFocusWindow*/,
 173                     AccessibleBrowseBoxObjType  /*_eObjType*/
 174                 ) const
 175             {
 176                 return NULL;
 177             }
 178
 179             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 180                 createAccessibleCheckBoxCell(
 181                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_rxParent*/,
 182                     IAccessibleTableProvider& /*_rBrowseBox*/,
 183                     const ::com::sun::star::uno::Reference< ::com::sun::star::awt::XWindow >& /*_xFocusWindow*/,
 184                     sal_Int32 /*_nRowPos*/,
 185                     sal_uInt16 /*_nColPos*/,
 186                     const TriState& /*_eState*/,
 187                     sal_Bool /*_bEnabled*/,
 188                     sal_Bool /*_bIsTriState*/
 189                 ) const
 190             {
 191                 return NULL;
 192             }
 193
 194             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 195                 createEditBrowseBoxTableCellAccess(
 196                     const ::com::sun::star::uno::Reference< com::sun::star::accessibility::XAccessible >& /*_rxParent*/,
 197                     const ::com::sun::star::uno::Reference< com::sun::star::accessibility::XAccessible >& /*_rxControlAccessible*/,
 198                     const ::com::sun::star::uno::Reference< ::com::sun::star::awt::XWindow >& /*_rxFocusWindow*/,
 199                     IAccessibleTableProvider& /*_rBrowseBox*/,
 200                     sal_Int32 /*_nRowPos*/,
 201                     sal_uInt16 /*_nColPos*/
 202                 ) const
 203             {
 204                 return NULL;
 205             }
 206         };
 207
 208         //----------------------------------------------------------------
 209         AccessibleDummyFactory::AccessibleDummyFactory()
 210         {
 211         }
 212
 213         //----------------------------------------------------------------
 214         AccessibleDummyFactory::~AccessibleDummyFactory()
 215         {
 216         }
 217
 218         //----------------------------------------------------------------
 219         oslInterlockedCount SAL_CALL AccessibleDummyFactory::acquire()
 220         {
 221             return osl_incrementInterlockedCount( &m_refCount );
 222         }
 223
 224         //----------------------------------------------------------------
 225         oslInterlockedCount SAL_CALL AccessibleDummyFactory::release()
 226         {
 227             if ( 0 == osl_decrementInterlockedCount( &m_refCount ) )
 228             {
 229                 delete this;
 230                 return 0;
 231             }
 232             return m_refCount;
 233         }
 234     }
 235
 236     //====================================================================
 237     //= AccessibleFactoryAccess
 238     //====================================================================
 239     //--------------------------------------------------------------------
 240     AccessibleFactoryAccess::AccessibleFactoryAccess()
 241         :m_bInitialized( false )
 242     {
 243     }
 244
 245     //--------------------------------------------------------------------
 246     extern "C" { static void SAL_CALL thisModule() {} }
 247
 248     void AccessibleFactoryAccess::ensureInitialized()
 249     {
 250         if ( m_bInitialized )
 251             return;
 252
 253         ::osl::MutexGuard aGuard( ::osl::Mutex::getGlobalMutex() );
 254
 255 #ifdef UNLOAD_ON_LAST_CLIENT_DYING
 256         if ( 1 == osl_incrementInterlockedCount( &s_nAccessibleFactoryAccesss ) )
 257         {   // the first client
 258 #endif // UNLOAD_ON_LAST_CLIENT_DYING
 259             // load the library implementing the factory
 260             if ( !s_pFactory.get() )
 261             {
 262                 const ::rtl::OUString sModuleName = ::rtl::OUString::createFromAscii(
 263                     SVLIBRARY( "acc" )
 264                 );
 265                 s_hAccessibleImplementationModule = osl_loadModuleRelative( &thisModule, sModuleName.pData, 0 );
 266                 if ( s_hAccessibleImplementationModule != NULL )
 267                 {
 268                     const ::rtl::OUString sFactoryCreationFunc =
 269                         ::rtl::OUString::createFromAscii( "getSvtAccessibilityComponentFactory" );
 270                     s_pAccessibleFactoryFunc = (GetSvtAccessibilityComponentFactory)
 271                         osl_getFunctionSymbol( s_hAccessibleImplementationModule, sFactoryCreationFunc.pData );
 272
 273                 }
 274                 OSL_ENSURE( s_pAccessibleFactoryFunc, "ac_registerClient: could not load the library, or not retrieve the needed symbol!" );
 275
 276                 // get a factory instance
 277                 if ( s_pAccessibleFactoryFunc )
 278                 {
 279                     IAccessibleFactory* pFactory = static_cast< IAccessibleFactory* >( (*s_pAccessibleFactoryFunc)() );
 280                     if ( pFactory )
 281                     {
 282                         s_pFactory = pFactory;
 283                         pFactory->release();
 284                     }
 285                 }
 286             }
 287
 288             if ( !s_pFactory.get() )
 289                 // the attempt to load the lib, or to create the factory, failed
 290                 // -> fall back to a dummy factory
 291                 s_pFactory = new AccessibleDummyFactory;
 292 #ifdef UNLOAD_ON_LAST_CLIENT_DYING
 293         }
 294 #endif
 295
 296         m_bInitialized = true;
 297     }
 298
 299     //--------------------------------------------------------------------
 300     AccessibleFactoryAccess::~AccessibleFactoryAccess()
 301     {
 302         if ( m_bInitialized )
 303         {
 304             ::osl::MutexGuard aGuard( ::osl::Mutex::getGlobalMutex() );
 305
 306 #ifdef UNLOAD_ON_LAST_CLIENT_DYING
 307             if( 0 == osl_decrementInterlockedCount( &s_nAccessibleFactoryAccesss ) )
 308             {
 309                 s_pFactory = NULL;
 310                 s_pAccessibleFactoryFunc = NULL;
 311                 if ( s_hAccessibleImplementationModule )
 312                 {
 313                     osl_unloadModule( s_hAccessibleImplementationModule );
 314                     s_hAccessibleImplementationModule = NULL;
 315                 }
 316             }
 317 #endif // UNLOAD_ON_LAST_CLIENT_DYING
 318         }
 319     }
 320
 321     //--------------------------------------------------------------------
 322     IAccessibleFactory& AccessibleFactoryAccess::getFactory()
 323     {
 324         ensureInitialized();
 325         DBG_ASSERT( s_pFactory.is(), "AccessibleFactoryAccess::getFactory: at least a dummy factory should have been created!" );
 326         return *s_pFactory;
 327     }
 328
 329 //........................................................................
 330 }   // namespace svt
 331 //........................................................................