svtools/source/misc/svtaccessiblefactory.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include "svtaccessiblefactory.hxx"
  21 #include <osl/module.h>
  22
  23 // #define UNLOAD_ON_LAST_CLIENT_DYING
  24     // this is not recommended currently. If enabled, the implementation will log
  25     // the number of active clients, and unload the acc library when the last client
  26     // goes away.
  27     // Sounds like a good idea, unfortunately, there's no guarantee that all objects
  28     // implemented in this library are already dead.
  29     // Iow, just because an object implementing an XAccessible (implemented in this lib
  30     // here) died, it's not said that everybody released all references to the
  31     // XAccessibleContext used by this component, and implemented in the acc lib.
  32     // So we cannot really unload the lib.
  33     //
  34     // Alternatively, if the lib would us own "usage counting", i.e. every component
  35     // implemented therein would affect a static ref count, the acc lib could care
  36     // for unloading itself.
  37
  38 //........................................................................
  39 namespace svt
  40 {
  41 //........................................................................
  42
  43     using namespace ::com::sun::star::uno;
  44     using namespace ::com::sun::star::awt;
  45     using namespace ::com::sun::star::accessibility;
  46
  47     namespace
  48     {
  49 #ifdef UNLOAD_ON_LAST_CLIENT_DYING
  50         static oslInterlockedCount                      s_nAccessibleFactoryAccesss = 0;
  51 #endif // UNLOAD_ON_LAST_CLIENT_DYING
  52 #ifndef DISABLE_DYNLOADING
  53         static oslModule                                s_hAccessibleImplementationModule = NULL;
  54 #endif
  55         static GetSvtAccessibilityComponentFactory      s_pAccessibleFactoryFunc = NULL;
  56         static ::rtl::Reference< IAccessibleFactory >   s_pFactory;
  57
  58         //====================================================================
  59         //= AccessibleDummyFactory
  60         //====================================================================
  61         class AccessibleDummyFactory : public IAccessibleFactory
  62         {
  63         public:
  64             AccessibleDummyFactory();
  65
  66         protected:
  67             virtual ~AccessibleDummyFactory();
  68
  69         private:
  70             AccessibleDummyFactory( const AccessibleDummyFactory& );            // never implemented
  71             AccessibleDummyFactory& operator=( const AccessibleDummyFactory& ); // never implemented
  72
  73             oslInterlockedCount m_refCount;
  74
  75         public:
  76             // IReference
  77             virtual oslInterlockedCount SAL_CALL acquire();
  78             virtual oslInterlockedCount SAL_CALL release();
  79
  80             // IAccessibleFactory
  81             virtual IAccessibleTabListBox*
  82                 createAccessibleTabListBox(
  83                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*rxParent*/,
  84                     SvHeaderTabListBox& /*rBox*/
  85                 ) const
  86             {
  87                 return NULL;
  88             }
  89
  90             virtual IAccessibleBrowseBox*
  91                 createAccessibleBrowseBox(
  92                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_rxParent*/,
  93                     IAccessibleTableProvider& /*_rBrowseBox*/
  94                 ) const
  95             {
  96                 return NULL;
  97             }
  98
  99             virtual table::IAccessibleTableControl*
 100                 createAccessibleTableControl(
 101                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_rxParent*/,
 102                     table::IAccessibleTable& /*_rTable*/
 103                 ) const
 104             {
 105                 return NULL;
 106             }
 107
 108             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 109                 createAccessibleIconChoiceCtrl(
 110                     SvtIconChoiceCtrl& /*_rIconCtrl*/,
 111                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_xParent*/
 112                 ) const
 113             {
 114                 return NULL;
 115             }
 116
 117             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 118                 createAccessibleTabBar(
 119                     TabBar& /*_rTabBar*/
 120                 ) const
 121             {
 122                 return NULL;
 123             }
 124
 125             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >
 126                 createAccessibleTextWindowContext(
 127                     VCLXWindow* /*pVclXWindow*/, TextEngine& /*rEngine*/, TextView& /*rView*/, bool /*bCompoundControlChild*/
 128                 ) const
 129             {
 130                 return NULL;
 131             }
 132
 133             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 134                 createAccessibleTreeListBox(
 135                     SvTreeListBox& /*_rListBox*/,
 136                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_xParent*/
 137                 ) const
 138             {
 139                 return NULL;
 140             }
 141
 142             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 143                 createAccessibleBrowseBoxHeaderBar(
 144                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*rxParent*/,
 145                     IAccessibleTableProvider& /*_rOwningTable*/,
 146                     AccessibleBrowseBoxObjType /*_eObjType*/
 147                 ) const
 148             {
 149                 return NULL;
 150             }
 151
 152             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 153                 createAccessibleBrowseBoxTableCell(
 154                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_rxParent*/,
 155                     IAccessibleTableProvider& /*_rBrowseBox*/,
 156                     const ::com::sun::star::uno::Reference< ::com::sun::star::awt::XWindow >& /*_xFocusWindow*/,
 157                     sal_Int32 /*_nRowId*/,
 158                     sal_uInt16 /*_nColId*/,
 159                     sal_Int32 /*_nOffset*/
 160                 ) const
 161             {
 162                 return NULL;
 163             }
 164
 165             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 166                 createAccessibleBrowseBoxHeaderCell(
 167                     sal_Int32 /*_nColumnRowId*/,
 168                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*rxParent*/,
 169                     IAccessibleTableProvider& /*_rBrowseBox*/,
 170                     const ::com::sun::star::uno::Reference< ::com::sun::star::awt::XWindow >& /*_xFocusWindow*/,
 171                     AccessibleBrowseBoxObjType  /*_eObjType*/
 172                 ) const
 173             {
 174                 return NULL;
 175             }
 176
 177             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 178                 createAccessibleCheckBoxCell(
 179                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*_rxParent*/,
 180                     IAccessibleTableProvider& /*_rBrowseBox*/,
 181                     const ::com::sun::star::uno::Reference< ::com::sun::star::awt::XWindow >& /*_xFocusWindow*/,
 182                     sal_Int32 /*_nRowPos*/,
 183                     sal_uInt16 /*_nColPos*/,
 184                     const TriState& /*_eState*/,
 185                     sal_Bool /*_bIsTriState*/
 186                 ) const
 187             {
 188                 return NULL;
 189             }
 190
 191             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
 192                 createEditBrowseBoxTableCellAccess(
 193                     const ::com::sun::star::uno::Reference< com::sun::star::accessibility::XAccessible >& /*_rxParent*/,
 194                     const ::com::sun::star::uno::Reference< com::sun::star::accessibility::XAccessible >& /*_rxControlAccessible*/,
 195                     const ::com::sun::star::uno::Reference< ::com::sun::star::awt::XWindow >& /*_rxFocusWindow*/,
 196                     IAccessibleTableProvider& /*_rBrowseBox*/,
 197                     sal_Int32 /*_nRowPos*/,
 198                     sal_uInt16 /*_nColPos*/
 199                 ) const
 200             {
 201                 return NULL;
 202             }
 203
 204             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >
 205                 createAccessibleToolPanelDeck(
 206                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*i_rAccessibleParent*/,
 207                     ::svt::ToolPanelDeck& /*i_rPanelDeck*/
 208                 )
 209             {
 210                 return NULL;
 211             }
 212             virtual ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >
 213                 createAccessibleToolPanelTabBar(
 214                     const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& /*i_rAccessibleParent*/,
 215                     ::svt::IToolPanelDeck& /*i_rPanelDeck*/,
 216                     ::svt::PanelTabBar& /*i_rTabBar*/
 217                 )
 218             {
 219                 return NULL;
 220             }
 221         };
 222
 223         //----------------------------------------------------------------
 224         AccessibleDummyFactory::AccessibleDummyFactory()
 225         {
 226         }
 227
 228         //----------------------------------------------------------------
 229         AccessibleDummyFactory::~AccessibleDummyFactory()
 230         {
 231         }
 232
 233         //----------------------------------------------------------------
 234         oslInterlockedCount SAL_CALL AccessibleDummyFactory::acquire()
 235         {
 236             return osl_atomic_increment( &m_refCount );
 237         }
 238
 239         //----------------------------------------------------------------
 240         oslInterlockedCount SAL_CALL AccessibleDummyFactory::release()
 241         {
 242             if ( 0 == osl_atomic_decrement( &m_refCount ) )
 243             {
 244                 delete this;
 245                 return 0;
 246             }
 247             return m_refCount;
 248         }
 249     }
 250
 251     //====================================================================
 252     //= AccessibleFactoryAccess
 253     //====================================================================
 254     //--------------------------------------------------------------------
 255     AccessibleFactoryAccess::AccessibleFactoryAccess()
 256         :m_bInitialized( false )
 257     {
 258     }
 259
 260     //--------------------------------------------------------------------
 261 #ifndef DISABLE_DYNLOADING
 262     extern "C" { static void SAL_CALL thisModule() {} }
 263 #else
 264     extern "C" void* getSvtAccessibilityComponentFactory();
 265 #endif
 266
 267     void AccessibleFactoryAccess::ensureInitialized()
 268     {
 269         if ( m_bInitialized )
 270             return;
 271
 272         ::osl::MutexGuard aGuard( ::osl::Mutex::getGlobalMutex() );
 273
 274 #ifdef UNLOAD_ON_LAST_CLIENT_DYING
 275         if ( 1 == osl_atomic_increment( &s_nAccessibleFactoryAccesss ) )
 276         {   // the first client
 277 #endif // UNLOAD_ON_LAST_CLIENT_DYING
 278             // load the library implementing the factory
 279             if ( !s_pFactory.get() )
 280             {
 281 #ifndef DISABLE_DYNLOADING
 282                 const OUString sModuleName( SVLIBRARY( "acc" ));
 283                 s_hAccessibleImplementationModule = osl_loadModuleRelative( &thisModule, sModuleName.pData, 0 );
 284                 if ( s_hAccessibleImplementationModule != NULL )
 285                 {
 286                     const OUString sFactoryCreationFunc( "getSvtAccessibilityComponentFactory" );
 287                     s_pAccessibleFactoryFunc = (GetSvtAccessibilityComponentFactory)
 288                         osl_getFunctionSymbol( s_hAccessibleImplementationModule, sFactoryCreationFunc.pData );
 289
 290                 }
 291                 OSL_ENSURE( s_pAccessibleFactoryFunc, "ac_registerClient: could not load the library, or not retrieve the needed symbol!" );
 292 #else
 293                 s_pAccessibleFactoryFunc = getSvtAccessibilityComponentFactory;
 294 #endif
 295                 // get a factory instance
 296                 if ( s_pAccessibleFactoryFunc )
 297                 {
 298                     IAccessibleFactory* pFactory = static_cast< IAccessibleFactory* >( (*s_pAccessibleFactoryFunc)() );
 299                     if ( pFactory )
 300                     {
 301                         s_pFactory = pFactory;
 302                         pFactory->release();
 303                     }
 304                 }
 305             }
 306
 307             if ( !s_pFactory.get() )
 308                 // the attempt to load the lib, or to create the factory, failed
 309                 // -> fall back to a dummy factory
 310                 s_pFactory = new AccessibleDummyFactory;
 311 #ifdef UNLOAD_ON_LAST_CLIENT_DYING
 312         }
 313 #endif
 314
 315         m_bInitialized = true;
 316     }
 317
 318     //--------------------------------------------------------------------
 319     AccessibleFactoryAccess::~AccessibleFactoryAccess()
 320     {
 321         if ( m_bInitialized )
 322         {
 323             ::osl::MutexGuard aGuard( ::osl::Mutex::getGlobalMutex() );
 324
 325 #ifdef UNLOAD_ON_LAST_CLIENT_DYING
 326             if( 0 == osl_atomic_decrement( &s_nAccessibleFactoryAccesss ) )
 327             {
 328                 s_pFactory = NULL;
 329                 s_pAccessibleFactoryFunc = NULL;
 330                 if ( s_hAccessibleImplementationModule )
 331                 {
 332                     osl_unloadModule( s_hAccessibleImplementationModule );
 333                     s_hAccessibleImplementationModule = NULL;
 334                 }
 335             }
 336 #endif // UNLOAD_ON_LAST_CLIENT_DYING
 337         }
 338     }
 339
 340     //--------------------------------------------------------------------
 341     IAccessibleFactory& AccessibleFactoryAccess::getFactory()
 342     {
 343         ensureInitialized();
 344         DBG_ASSERT( s_pFactory.is(), "AccessibleFactoryAccess::getFactory: at least a dummy factory should have been created!" );
 345         return *s_pFactory;
 346     }
 347
 348 //........................................................................
 349 }   // namespace svt
 350 //........................................................................
 351
 352 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */