framework/source/fwe/helper/undomanagerhelper.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 <framework/undomanagerhelper.hxx>
  21 #include <framework/imutex.hxx>
  22
  23 #include <com/sun/star/document/EmptyUndoStackException.hpp>
  24 #include <com/sun/star/document/UndoContextNotClosedException.hpp>
  25 #include <com/sun/star/document/UndoFailedException.hpp>
  26 #include <com/sun/star/document/XUndoManager.hpp>
  27 #include <com/sun/star/lang/XComponent.hpp>
  28 #include <com/sun/star/util/InvalidStateException.hpp>
  29 #include <com/sun/star/util/NotLockedException.hpp>
  30 #include <com/sun/star/util/XModifyListener.hpp>
  31
  32 #include <comphelper/interfacecontainer4.hxx>
  33 #include <cppuhelper/exc_hlp.hxx>
  34 #include <comphelper/flagguard.hxx>
  35 #include <comphelper/asyncnotification.hxx>
  36 #include <svl/undo.hxx>
  37 #include <comphelper/diagnose_ex.hxx>
  38 #include <osl/conditn.hxx>
  39 #include <vcl/svapp.hxx>
  40
  41 #include <functional>
  42 #include <mutex>
  43 #include <stack>
  44 #include <queue>
  45 #include <utility>
  46
  47 namespace framework
  48 {
  49
  50     using ::com::sun::star::uno::Reference;
  51     using ::com::sun::star::uno::XInterface;
  52     using ::com::sun::star::uno::UNO_QUERY;
  53     using ::com::sun::star::uno::Exception;
  54     using ::com::sun::star::uno::RuntimeException;
  55     using ::com::sun::star::uno::Any;
  56     using ::com::sun::star::uno::Sequence;
  57     using ::com::sun::star::document::XUndoManagerListener;
  58     using ::com::sun::star::document::UndoManagerEvent;
  59     using ::com::sun::star::document::EmptyUndoStackException;
  60     using ::com::sun::star::document::UndoContextNotClosedException;
  61     using ::com::sun::star::document::UndoFailedException;
  62     using ::com::sun::star::util::NotLockedException;
  63     using ::com::sun::star::lang::EventObject;
  64     using ::com::sun::star::document::XUndoAction;
  65     using ::com::sun::star::lang::XComponent;
  66     using ::com::sun::star::document::XUndoManager;
  67     using ::com::sun::star::util::InvalidStateException;
  68     using ::com::sun::star::lang::IllegalArgumentException;
  69     using ::com::sun::star::util::XModifyListener;
  70
  71     //= UndoActionWrapper
  72
  73     namespace {
  74
  75     class UndoActionWrapper : public SfxUndoAction
  76     {
  77     public:
  78         explicit            UndoActionWrapper(
  79                                 Reference< XUndoAction > const& i_undoAction
  80                             );
  81         virtual             ~UndoActionWrapper() override;
  82
  83         virtual OUString    GetComment() const override;
  84         virtual void        Undo() override;
  85         virtual void        Redo() override;
  86         virtual bool        CanRepeat(SfxRepeatTarget&) const override;
  87
  88     private:
  89         const Reference< XUndoAction >  m_xUndoAction;
  90     };
  91
  92     }
  93
  94     UndoActionWrapper::UndoActionWrapper( Reference< XUndoAction > const& i_undoAction )
  95         : m_xUndoAction( i_undoAction )
  96     {
  97         ENSURE_OR_THROW( m_xUndoAction.is(), "illegal undo action" );
  98     }
  99
 100     UndoActionWrapper::~UndoActionWrapper()
 101     {
 102         try
 103         {
 104             Reference< XComponent > xComponent( m_xUndoAction, UNO_QUERY );
 105             if ( xComponent.is() )
 106                 xComponent->dispose();
 107         }
 108         catch( const Exception& )
 109         {
 110             DBG_UNHANDLED_EXCEPTION("fwk");
 111         }
 112     }
 113
 114     OUString UndoActionWrapper::GetComment() const
 115     {
 116         OUString sComment;
 117         try
 118         {
 119             sComment = m_xUndoAction->getTitle();
 120         }
 121         catch( const Exception& )
 122         {
 123             DBG_UNHANDLED_EXCEPTION("fwk");
 124         }
 125         return sComment;
 126     }
 127
 128     void UndoActionWrapper::Undo()
 129     {
 130         m_xUndoAction->undo();
 131     }
 132
 133     void UndoActionWrapper::Redo()
 134     {
 135         m_xUndoAction->redo();
 136     }
 137
 138     bool UndoActionWrapper::CanRepeat(SfxRepeatTarget&) const
 139     {
 140         return false;
 141     }
 142
 143     //= UndoManagerRequest
 144
 145     namespace {
 146
 147     class UndoManagerRequest : public ::comphelper::AnyEvent
 148     {
 149     public:
 150         explicit UndoManagerRequest( ::std::function<void ()>  i_request )
 151             :m_request(std::move( i_request ))
 152         {
 153             m_finishCondition.reset();
 154         }
 155
 156         void execute()
 157         {
 158             try
 159             {
 160                 m_request();
 161             }
 162             catch( const Exception& )
 163             {
 164                 m_caughtException = ::cppu::getCaughtException();
 165             }
 166             m_finishCondition.set();
 167         }
 168
 169         void wait()
 170         {
 171             m_finishCondition.wait();
 172             if ( m_caughtException.hasValue() )
 173                 ::cppu::throwException( m_caughtException );
 174         }
 175
 176         void cancel( const Reference< XInterface >& i_context )
 177         {
 178             m_caughtException <<= RuntimeException(
 179                 u"Concurrency error: an earlier operation on the stack failed."_ustr,
 180                 i_context
 181             );
 182             m_finishCondition.set();
 183         }
 184
 185     protected:
 186         virtual ~UndoManagerRequest() override
 187         {
 188         }
 189
 190     private:
 191         ::std::function<void ()>    m_request;
 192         Any                         m_caughtException;
 193         ::osl::Condition            m_finishCondition;
 194     };
 195
 196     }
 197
 198     //= UndoManagerHelper_Impl
 199
 200     class UndoManagerHelper_Impl : public SfxUndoListener
 201     {
 202     private:
 203         ::osl::Mutex                        m_aMutex;
 204         /// Use different mutex for listeners to prevent ABBA deadlocks
 205         std::mutex                          m_aListenerMutex;
 206         std::mutex                          m_aQueueMutex;
 207         bool                                m_bAPIActionRunning;
 208         std::atomic<bool>                   m_bProcessingEvents;
 209         sal_Int32                           m_nLockCount;
 210         ::comphelper::OInterfaceContainerHelper4<XUndoManagerListener>   m_aUndoListeners;
 211         ::comphelper::OInterfaceContainerHelper4<XModifyListener>   m_aModifyListeners;
 212         IUndoManagerImplementation&         m_rUndoManagerImplementation;
 213         ::std::stack< bool >                m_aContextVisibilities;
 214 #if OSL_DEBUG_LEVEL > 0
 215         bool                                m_bContextAPIFlagsEverPushed = {false};
 216         ::std::stack< bool >                m_aContextAPIFlags;
 217 #endif
 218         ::std::queue< ::rtl::Reference< UndoManagerRequest > >
 219                                             m_aEventQueue;
 220
 221     public:
 222         ::osl::Mutex&   getMutex() { return m_aMutex; }
 223
 224     public:
 225         explicit UndoManagerHelper_Impl( IUndoManagerImplementation& i_undoManagerImpl )
 226             :m_bAPIActionRunning( false )
 227             ,m_bProcessingEvents( false )
 228             ,m_nLockCount( 0 )
 229             ,m_rUndoManagerImplementation( i_undoManagerImpl )
 230         {
 231             getUndoManager().AddUndoListener( *this );
 232         }
 233
 234         virtual ~UndoManagerHelper_Impl()
 235         {
 236         }
 237
 238         SfxUndoManager& getUndoManager() const
 239         {
 240             return m_rUndoManagerImplementation.getImplUndoManager();
 241         }
 242
 243         Reference< XUndoManager > getXUndoManager() const
 244         {
 245             return m_rUndoManagerImplementation.getThis();
 246         }
 247
 248         // SfxUndoListener
 249         virtual void actionUndone( const OUString& i_actionComment ) override;
 250         virtual void actionRedone( const OUString& i_actionComment ) override;
 251         virtual void undoActionAdded( const OUString& i_actionComment ) override;
 252         virtual void cleared() override;
 253         virtual void clearedRedo() override;
 254         virtual void resetAll() override;
 255         virtual void listActionEntered( const OUString& i_comment ) override;
 256         virtual void listActionLeft( const OUString& i_comment ) override;
 257         virtual void listActionCancelled() override;
 258
 259         // public operations
 260         void disposing();
 261
 262         void enterUndoContext( const OUString& i_title, const bool i_hidden, IMutexGuard& i_instanceLock );
 263         void leaveUndoContext( IMutexGuard& i_instanceLock );
 264         void addUndoAction( const Reference< XUndoAction >& i_action, IMutexGuard& i_instanceLock );
 265         void undo( IMutexGuard& i_instanceLock );
 266         void redo( IMutexGuard& i_instanceLock );
 267         void clear( IMutexGuard& i_instanceLock );
 268         void clearRedo( IMutexGuard& i_instanceLock );
 269         void reset( IMutexGuard& i_instanceLock );
 270
 271         void lock();
 272         void unlock();
 273
 274         void addUndoManagerListener( const Reference< XUndoManagerListener >& i_listener )
 275         {
 276             std::unique_lock g(m_aListenerMutex);
 277             m_aUndoListeners.addInterface( g, i_listener );
 278         }
 279
 280         void removeUndoManagerListener( const Reference< XUndoManagerListener >& i_listener )
 281         {
 282             std::unique_lock g(m_aListenerMutex);
 283             m_aUndoListeners.removeInterface( g, i_listener );
 284         }
 285
 286         void addModifyListener( const Reference< XModifyListener >& i_listener )
 287         {
 288             std::unique_lock g(m_aListenerMutex);
 289             m_aModifyListeners.addInterface( g, i_listener );
 290         }
 291
 292         void removeModifyListener( const Reference< XModifyListener >& i_listener )
 293         {
 294             std::unique_lock g(m_aListenerMutex);
 295             m_aModifyListeners.removeInterface( g, i_listener );
 296         }
 297
 298         UndoManagerEvent
 299             buildEvent( OUString const& i_title ) const;
 300
 301         void impl_notifyModified();
 302         void notify(    OUString const& i_title,
 303                         void ( SAL_CALL XUndoManagerListener::*i_notificationMethod )( const UndoManagerEvent& )
 304                     );
 305         void notify( void ( SAL_CALL XUndoManagerListener::*i_notificationMethod )( const EventObject& ) );
 306
 307     private:
 308         /// adds a function to be called to the request processor's queue
 309         void impl_processRequest(::std::function<void ()> const& i_request, IMutexGuard& i_instanceLock);
 310
 311         /// impl-versions of the XUndoManager API.
 312         void impl_enterUndoContext( const OUString& i_title, const bool i_hidden );
 313         void impl_leaveUndoContext();
 314         void impl_addUndoAction( const Reference< XUndoAction >& i_action );
 315         void impl_doUndoRedo( IMutexGuard& i_externalLock, const bool i_undo );
 316         void impl_clear();
 317         void impl_clearRedo();
 318         void impl_reset();
 319     };
 320
 321     void UndoManagerHelper_Impl::disposing()
 322     {
 323         EventObject aEvent;
 324         aEvent.Source = getXUndoManager();
 325         {
 326             std::unique_lock g(m_aListenerMutex);
 327             m_aUndoListeners.disposeAndClear( g, aEvent );
 328             m_aModifyListeners.disposeAndClear( g, aEvent );
 329         }
 330         ::osl::MutexGuard aGuard( m_aMutex );
 331
 332         getUndoManager().RemoveUndoListener( *this );
 333     }
 334
 335     UndoManagerEvent UndoManagerHelper_Impl::buildEvent( OUString const& i_title ) const
 336     {
 337         UndoManagerEvent aEvent;
 338         aEvent.Source = getXUndoManager();
 339         aEvent.UndoActionTitle = i_title;
 340         aEvent.UndoContextDepth = getUndoManager().GetListActionDepth();
 341         return aEvent;
 342     }
 343
 344     void UndoManagerHelper_Impl::impl_notifyModified()
 345     {
 346         const EventObject aEvent( getXUndoManager() );
 347         std::unique_lock g(m_aListenerMutex);
 348         m_aModifyListeners.notifyEach( g, &XModifyListener::modified, aEvent );
 349     }
 350
 351     void UndoManagerHelper_Impl::notify( OUString const& i_title,
 352         void ( SAL_CALL XUndoManagerListener::*i_notificationMethod )( const UndoManagerEvent& ) )
 353     {
 354         const UndoManagerEvent aEvent( buildEvent( i_title ) );
 355
 356         // TODO: this notification method here is used by UndoManagerHelper_Impl, to multiplex the notifications we
 357         // receive from the SfxUndoManager. Those notifications are sent with a locked SolarMutex, which means
 358         // we're doing the multiplexing here with a locked SM, too. Which is Bad (TM).
 359         // Fixing this properly would require outsourcing all the notifications into an own thread - which might lead
 360         // to problems of its own, since clients might expect synchronous notifications.
 361
 362         {
 363             std::unique_lock g(m_aListenerMutex);
 364             m_aUndoListeners.notifyEach( g, i_notificationMethod, aEvent );
 365         }
 366         impl_notifyModified();
 367     }
 368
 369     void UndoManagerHelper_Impl::notify( void ( SAL_CALL XUndoManagerListener::*i_notificationMethod )( const EventObject& ) )
 370     {
 371         const EventObject aEvent( getXUndoManager() );
 372
 373         // TODO: the same comment as in the other notify, regarding SM locking applies here ...
 374         {
 375             std::unique_lock g(m_aListenerMutex);
 376             m_aUndoListeners.notifyEach( g, i_notificationMethod, aEvent );
 377         }
 378         impl_notifyModified();
 379     }
 380
 381     void UndoManagerHelper_Impl::enterUndoContext( const OUString& i_title, const bool i_hidden, IMutexGuard& i_instanceLock )
 382     {
 383         impl_processRequest(
 384             [this, &i_title, i_hidden] () { return this->impl_enterUndoContext(i_title, i_hidden); },
 385             i_instanceLock
 386         );
 387     }
 388
 389     void UndoManagerHelper_Impl::leaveUndoContext( IMutexGuard& i_instanceLock )
 390     {
 391         impl_processRequest(
 392             [this] () { return this->impl_leaveUndoContext(); },
 393             i_instanceLock
 394         );
 395     }
 396
 397     void UndoManagerHelper_Impl::addUndoAction( const Reference< XUndoAction >& i_action, IMutexGuard& i_instanceLock )
 398     {
 399         if ( !i_action.is() )
 400             throw IllegalArgumentException(
 401                 u"illegal undo action object"_ustr,
 402                 getXUndoManager(),
 403                 1
 404             );
 405
 406         impl_processRequest(
 407             [this, &i_action] () { return this->impl_addUndoAction(i_action); },
 408             i_instanceLock
 409         );
 410     }
 411
 412     void UndoManagerHelper_Impl::clear( IMutexGuard& i_instanceLock )
 413     {
 414         impl_processRequest(
 415             [this] () { return this->impl_clear(); },
 416             i_instanceLock
 417         );
 418     }
 419
 420     void UndoManagerHelper_Impl::clearRedo( IMutexGuard& i_instanceLock )
 421     {
 422         impl_processRequest(
 423             [this] () { return this->impl_clearRedo(); },
 424             i_instanceLock
 425         );
 426     }
 427
 428     void UndoManagerHelper_Impl::reset( IMutexGuard& i_instanceLock )
 429     {
 430         impl_processRequest(
 431             [this] () { return this->impl_reset(); },
 432             i_instanceLock
 433         );
 434     }
 435
 436     void UndoManagerHelper_Impl::lock()
 437     {
 438         // SYNCHRONIZED --->
 439         ::osl::MutexGuard aGuard( getMutex() );
 440
 441         if ( ++m_nLockCount == 1 )
 442         {
 443             SfxUndoManager& rUndoManager = getUndoManager();
 444             rUndoManager.EnableUndo( false );
 445         }
 446         // <--- SYNCHRONIZED
 447     }
 448
 449     void UndoManagerHelper_Impl::unlock()
 450     {
 451         // SYNCHRONIZED --->
 452         ::osl::MutexGuard aGuard( getMutex() );
 453
 454         if ( m_nLockCount == 0 )
 455             throw NotLockedException( u"Undo manager is not locked"_ustr, getXUndoManager() );
 456
 457         if ( --m_nLockCount == 0 )
 458         {
 459             SfxUndoManager& rUndoManager = getUndoManager();
 460             rUndoManager.EnableUndo( true );
 461         }
 462         // <--- SYNCHRONIZED
 463     }
 464
 465     void UndoManagerHelper_Impl::impl_processRequest(::std::function<void ()> const& i_request, IMutexGuard& i_instanceLock)
 466     {
 467         // create the request, and add it to our queue
 468         ::rtl::Reference< UndoManagerRequest > pRequest( new UndoManagerRequest( i_request ) );
 469         {
 470             std::unique_lock aQueueGuard( m_aQueueMutex );
 471             m_aEventQueue.push( pRequest );
 472         }
 473
 474         i_instanceLock.clear();
 475
 476         if ( m_bProcessingEvents )
 477         {
 478             // another thread is processing the event queue currently => it will also process the event which we just added
 479             pRequest->wait();
 480             return;
 481         }
 482
 483         m_bProcessingEvents = true;
 484         do
 485         {
 486             pRequest.clear();
 487             {
 488                 std::unique_lock aQueueGuard( m_aQueueMutex );
 489                 if ( m_aEventQueue.empty() )
 490                 {
 491                     // reset the flag before releasing the queue mutex, otherwise it's possible that another thread
 492                     // could add an event after we release the mutex, but before we reset the flag. If then this other
 493                     // thread checks the flag before be reset it, this thread's event would starve.
 494                     m_bProcessingEvents = false;
 495                     return;
 496                 }
 497                 pRequest = m_aEventQueue.front();
 498                 m_aEventQueue.pop();
 499             }
 500             try
 501             {
 502                 pRequest->execute();
 503                 pRequest->wait();
 504             }
 505             catch( ... )
 506             {
 507                 {
 508                     // no chance to process further requests, if the current one failed
 509                     // => discard them
 510                     std::unique_lock aQueueGuard( m_aQueueMutex );
 511                     while ( !m_aEventQueue.empty() )
 512                     {
 513                         pRequest = m_aEventQueue.front();
 514                         m_aEventQueue.pop();
 515                         pRequest->cancel( getXUndoManager() );
 516                     }
 517                     m_bProcessingEvents = false;
 518                 }
 519                 // re-throw the error
 520                 throw;
 521             }
 522         }
 523         while ( true );
 524     }
 525
 526     void UndoManagerHelper_Impl::impl_enterUndoContext( const OUString& i_title, const bool i_hidden )
 527     {
 528         // SYNCHRONIZED --->
 529         ::osl::ClearableMutexGuard aGuard( m_aMutex );
 530
 531         SfxUndoManager& rUndoManager = getUndoManager();
 532         if ( !rUndoManager.IsUndoEnabled() )
 533             // ignore this request if the manager is locked
 534             return;
 535
 536         if ( i_hidden && ( rUndoManager.GetUndoActionCount() == 0 ) )
 537             throw EmptyUndoStackException(
 538                 u"can't enter a hidden context without a previous Undo action"_ustr,
 539                 m_rUndoManagerImplementation.getThis()
 540             );
 541
 542         {
 543             ::comphelper::FlagGuard aNotificationGuard( m_bAPIActionRunning );
 544             rUndoManager.EnterListAction( i_title, OUString(), 0, ViewShellId(-1) );
 545         }
 546
 547         m_aContextVisibilities.push( i_hidden );
 548
 549         const UndoManagerEvent aEvent( buildEvent( i_title ) );
 550         aGuard.clear();
 551         // <--- SYNCHRONIZED
 552
 553         {
 554             std::unique_lock g(m_aListenerMutex);
 555             m_aUndoListeners.notifyEach( g, i_hidden ? &XUndoManagerListener::enteredHiddenContext : &XUndoManagerListener::enteredContext, aEvent );
 556         }
 557         impl_notifyModified();
 558     }
 559
 560     void UndoManagerHelper_Impl::impl_leaveUndoContext()
 561     {
 562         // SYNCHRONIZED --->
 563         ::osl::ClearableMutexGuard aGuard( m_aMutex );
 564
 565         SfxUndoManager& rUndoManager = getUndoManager();
 566         if ( !rUndoManager.IsUndoEnabled() )
 567             // ignore this request if the manager is locked
 568             return;
 569
 570         if ( !rUndoManager.IsInListAction() )
 571             throw InvalidStateException(
 572                 u"no active undo context"_ustr,
 573                 getXUndoManager()
 574             );
 575
 576         size_t nContextElements = 0;
 577
 578         const bool isHiddenContext = m_aContextVisibilities.top();
 579         m_aContextVisibilities.pop();
 580
 581         const bool bHadRedoActions = ( rUndoManager.GetRedoActionCount( SfxUndoManager::TopLevel ) > 0 );
 582         {
 583             ::comphelper::FlagGuard aNotificationGuard( m_bAPIActionRunning );
 584             if ( isHiddenContext )
 585                 nContextElements = rUndoManager.LeaveAndMergeListAction();
 586             else
 587                 nContextElements = rUndoManager.LeaveListAction();
 588         }
 589         const bool bHasRedoActions = ( rUndoManager.GetRedoActionCount( SfxUndoManager::TopLevel ) > 0 );
 590
 591         // prepare notification
 592         void ( SAL_CALL XUndoManagerListener::*notificationMethod )( const UndoManagerEvent& ) = nullptr;
 593
 594         UndoManagerEvent aContextEvent( buildEvent( OUString() ) );
 595         const EventObject aClearedEvent( getXUndoManager() );
 596         if ( nContextElements == 0 )
 597         {
 598             notificationMethod = &XUndoManagerListener::cancelledContext;
 599         }
 600         else if ( isHiddenContext )
 601         {
 602             notificationMethod = &XUndoManagerListener::leftHiddenContext;
 603         }
 604         else
 605         {
 606             aContextEvent.UndoActionTitle = rUndoManager.GetUndoActionComment();
 607             notificationMethod = &XUndoManagerListener::leftContext;
 608         }
 609
 610         aGuard.clear();
 611         // <--- SYNCHRONIZED
 612
 613         {
 614             std::unique_lock g(m_aListenerMutex);
 615             if ( bHadRedoActions && !bHasRedoActions )
 616                 m_aUndoListeners.notifyEach( g, &XUndoManagerListener::redoActionsCleared, aClearedEvent );
 617             m_aUndoListeners.notifyEach( g, notificationMethod, aContextEvent );
 618         }
 619         impl_notifyModified();
 620     }
 621
 622     void UndoManagerHelper_Impl::impl_doUndoRedo( IMutexGuard& i_externalLock, const bool i_undo )
 623     {
 624         ::osl::Guard< ::framework::IMutex > aExternalGuard( i_externalLock.getGuardedMutex() );
 625             // note that this assumes that the mutex has been released in the thread which added the
 626             // Undo/Redo request, so we can successfully acquire it
 627
 628         // SYNCHRONIZED --->
 629         ::osl::ClearableMutexGuard aGuard( m_aMutex );
 630
 631         SfxUndoManager& rUndoManager = getUndoManager();
 632         if ( rUndoManager.IsInListAction() )
 633             throw UndoContextNotClosedException( OUString(), getXUndoManager() );
 634
 635         const size_t nElements  =   i_undo
 636                                 ?   rUndoManager.GetUndoActionCount( SfxUndoManager::TopLevel )
 637                                 :   rUndoManager.GetRedoActionCount( SfxUndoManager::TopLevel );
 638         if ( nElements == 0 )
 639             throw EmptyUndoStackException(u"stack is empty"_ustr, getXUndoManager() );
 640
 641         aGuard.clear();
 642         // <--- SYNCHRONIZED
 643
 644         try
 645         {
 646             if ( i_undo )
 647                 rUndoManager.Undo();
 648             else
 649                 rUndoManager.Redo();
 650         }
 651         catch( const RuntimeException& ) { /* allowed to leave here */ throw; }
 652         catch( const UndoFailedException& ) { /* allowed to leave here */ throw; }
 653         catch( const Exception& )
 654         {
 655             // not allowed to leave
 656             const Any aError( ::cppu::getCaughtException() );
 657             throw UndoFailedException( OUString(), getXUndoManager(), aError );
 658         }
 659
 660         // note that in opposite to all of the other methods, we do *not* have our mutex locked when calling
 661         // into the SfxUndoManager implementation. This ensures that an actual XUndoAction::undo/redo is also
 662         // called without our mutex being locked.
 663         // As a consequence, we do not set m_bAPIActionRunning here. Instead, our actionUndone/actionRedone methods
 664         // *always* multiplex the event to our XUndoManagerListeners, not only when m_bAPIActionRunning is FALSE (This
 665         // again is different from all other SfxUndoListener methods).
 666         // So, we do not need to do this notification here ourself.
 667     }
 668
 669     void UndoManagerHelper_Impl::impl_addUndoAction( const Reference< XUndoAction >& i_action )
 670     {
 671         // SYNCHRONIZED --->
 672         ::osl::ClearableMutexGuard aGuard( m_aMutex );
 673
 674         SfxUndoManager& rUndoManager = getUndoManager();
 675         if ( !rUndoManager.IsUndoEnabled() )
 676             // ignore the request if the manager is locked
 677             return;
 678
 679         const UndoManagerEvent aEventAdd( buildEvent( i_action->getTitle() ) );
 680         const EventObject aEventClear( getXUndoManager() );
 681
 682         const bool bHadRedoActions = ( rUndoManager.GetRedoActionCount() > 0 );
 683         {
 684             ::comphelper::FlagGuard aNotificationGuard( m_bAPIActionRunning );
 685             rUndoManager.AddUndoAction( std::make_unique<UndoActionWrapper>( i_action ) );
 686         }
 687         const bool bHasRedoActions = ( rUndoManager.GetRedoActionCount() > 0 );
 688
 689         aGuard.clear();
 690         // <--- SYNCHRONIZED
 691
 692         {
 693             std::unique_lock g(m_aListenerMutex);
 694             m_aUndoListeners.notifyEach( g, &XUndoManagerListener::undoActionAdded, aEventAdd );
 695             if ( bHadRedoActions && !bHasRedoActions )
 696                 m_aUndoListeners.notifyEach( g, &XUndoManagerListener::redoActionsCleared, aEventClear );
 697         }
 698         impl_notifyModified();
 699     }
 700
 701     void UndoManagerHelper_Impl::impl_clear()
 702     {
 703         EventObject aEvent;
 704         {
 705             SolarMutexGuard aGuard;
 706             ::osl::MutexGuard aGuard2( m_aMutex );
 707
 708             SfxUndoManager& rUndoManager = getUndoManager();
 709             if ( rUndoManager.IsInListAction() )
 710                 throw UndoContextNotClosedException( OUString(), getXUndoManager() );
 711
 712             {
 713                 ::comphelper::FlagGuard aNotificationGuard( m_bAPIActionRunning );
 714                 rUndoManager.Clear();
 715             }
 716
 717             aEvent = EventObject( getXUndoManager() );
 718         }
 719
 720         {
 721             std::unique_lock g(m_aListenerMutex);
 722             m_aUndoListeners.notifyEach( g, &XUndoManagerListener::allActionsCleared, aEvent );
 723         }
 724         impl_notifyModified();
 725     }
 726
 727     void UndoManagerHelper_Impl::impl_clearRedo()
 728     {
 729         // SYNCHRONIZED --->
 730         ::osl::ClearableMutexGuard aGuard( m_aMutex );
 731
 732         SfxUndoManager& rUndoManager = getUndoManager();
 733         if ( rUndoManager.IsInListAction() )
 734             throw UndoContextNotClosedException( OUString(), getXUndoManager() );
 735
 736         {
 737             ::comphelper::FlagGuard aNotificationGuard( m_bAPIActionRunning );
 738             rUndoManager.ClearRedo();
 739         }
 740
 741         const EventObject aEvent( getXUndoManager() );
 742         aGuard.clear();
 743         // <--- SYNCHRONIZED
 744
 745         {
 746             std::unique_lock g(m_aListenerMutex);
 747             m_aUndoListeners.notifyEach( g, &XUndoManagerListener::redoActionsCleared, aEvent );
 748         }
 749         impl_notifyModified();
 750     }
 751
 752     void UndoManagerHelper_Impl::impl_reset()
 753     {
 754         // SYNCHRONIZED --->
 755         ::osl::ClearableMutexGuard aGuard( m_aMutex );
 756
 757         SfxUndoManager& rUndoManager = getUndoManager();
 758         {
 759             ::comphelper::FlagGuard aNotificationGuard( m_bAPIActionRunning );
 760             rUndoManager.Reset();
 761         }
 762
 763         const EventObject aEvent( getXUndoManager() );
 764         aGuard.clear();
 765         // <--- SYNCHRONIZED
 766
 767         {
 768             std::unique_lock g(m_aListenerMutex);
 769             m_aUndoListeners.notifyEach( g, &XUndoManagerListener::resetAll, aEvent );
 770         }
 771         impl_notifyModified();
 772     }
 773
 774     void UndoManagerHelper_Impl::actionUndone( const OUString& i_actionComment )
 775     {
 776         UndoManagerEvent aEvent;
 777         aEvent.Source = getXUndoManager();
 778         aEvent.UndoActionTitle = i_actionComment;
 779         aEvent.UndoContextDepth = 0;    // Undo can happen on level 0 only
 780         {
 781             std::unique_lock g(m_aListenerMutex);
 782             m_aUndoListeners.notifyEach( g, &XUndoManagerListener::actionUndone, aEvent );
 783         }
 784         impl_notifyModified();
 785     }
 786
 787     void UndoManagerHelper_Impl::actionRedone( const OUString& i_actionComment )
 788     {
 789         UndoManagerEvent aEvent;
 790         aEvent.Source = getXUndoManager();
 791         aEvent.UndoActionTitle = i_actionComment;
 792         aEvent.UndoContextDepth = 0;    // Redo can happen on level 0 only
 793         {
 794             std::unique_lock g(m_aListenerMutex);
 795             m_aUndoListeners.notifyEach( g, &XUndoManagerListener::actionRedone, aEvent );
 796         }
 797         impl_notifyModified();
 798     }
 799
 800     void UndoManagerHelper_Impl::undoActionAdded( const OUString& i_actionComment )
 801     {
 802         if ( m_bAPIActionRunning )
 803             return;
 804
 805         notify( i_actionComment, &XUndoManagerListener::undoActionAdded );
 806     }
 807
 808     void UndoManagerHelper_Impl::cleared()
 809     {
 810         if ( m_bAPIActionRunning )
 811             return;
 812
 813         notify( &XUndoManagerListener::allActionsCleared );
 814     }
 815
 816     void UndoManagerHelper_Impl::clearedRedo()
 817     {
 818         if ( m_bAPIActionRunning )
 819             return;
 820
 821         notify( &XUndoManagerListener::redoActionsCleared );
 822     }
 823
 824     void UndoManagerHelper_Impl::resetAll()
 825     {
 826         if ( m_bAPIActionRunning )
 827             return;
 828
 829         notify( &XUndoManagerListener::resetAll );
 830     }
 831
 832     void UndoManagerHelper_Impl::listActionEntered( const OUString& i_comment )
 833     {
 834 #if OSL_DEBUG_LEVEL > 0
 835         m_aContextAPIFlags.push( m_bAPIActionRunning );
 836         m_bContextAPIFlagsEverPushed = true;
 837 #endif
 838
 839         if ( m_bAPIActionRunning )
 840             return;
 841
 842         notify( i_comment, &XUndoManagerListener::enteredContext );
 843     }
 844
 845     void UndoManagerHelper_Impl::listActionLeft( const OUString& i_comment )
 846     {
 847 #if OSL_DEBUG_LEVEL > 0
 848         // It may happen that the very first event listener is added during a
 849         // list action after listActionEntered() was already called, e.g. Calc
 850         // formula calculation event listener during the input of the very
 851         // first formula. Instead of checking m_aContextAPIFlags for empty,
 852         // still assert (on calling top()) other stack mismatches but ignore
 853         // this one case. See tdf#142980
 854         if (m_bContextAPIFlagsEverPushed)
 855         {
 856             const bool bCurrentContextIsAPIContext = m_aContextAPIFlags.top();
 857             m_aContextAPIFlags.pop();
 858             OSL_ENSURE( bCurrentContextIsAPIContext == m_bAPIActionRunning, "UndoManagerHelper_Impl::listActionLeft: API and non-API contexts interwoven!" );
 859         }
 860 #endif
 861
 862         if ( m_bAPIActionRunning )
 863             return;
 864
 865         notify( i_comment, &XUndoManagerListener::leftContext );
 866     }
 867
 868     void UndoManagerHelper_Impl::listActionCancelled()
 869     {
 870 #if OSL_DEBUG_LEVEL > 0
 871         const bool bCurrentContextIsAPIContext = m_aContextAPIFlags.top();
 872         m_aContextAPIFlags.pop();
 873         OSL_ENSURE( bCurrentContextIsAPIContext == m_bAPIActionRunning, "UndoManagerHelper_Impl::listActionCancelled: API and non-API contexts interwoven!" );
 874 #endif
 875
 876         if ( m_bAPIActionRunning )
 877             return;
 878
 879         notify( OUString(), &XUndoManagerListener::cancelledContext );
 880     }
 881
 882     //= UndoManagerHelper
 883
 884     UndoManagerHelper::UndoManagerHelper( IUndoManagerImplementation& i_undoManagerImpl )
 885         :m_xImpl( new UndoManagerHelper_Impl( i_undoManagerImpl ) )
 886     {
 887     }
 888
 889     UndoManagerHelper::~UndoManagerHelper()
 890     {
 891     }
 892
 893     void UndoManagerHelper::disposing()
 894     {
 895         m_xImpl->disposing();
 896     }
 897
 898     void UndoManagerHelper::enterUndoContext( const OUString& i_title, IMutexGuard& i_instanceLock )
 899     {
 900         m_xImpl->enterUndoContext( i_title, false, i_instanceLock );
 901     }
 902
 903     void UndoManagerHelper::enterHiddenUndoContext( IMutexGuard& i_instanceLock )
 904     {
 905         m_xImpl->enterUndoContext( OUString(), true, i_instanceLock );
 906     }
 907
 908     void UndoManagerHelper::leaveUndoContext( IMutexGuard& i_instanceLock )
 909     {
 910         m_xImpl->leaveUndoContext( i_instanceLock );
 911     }
 912
 913     void UndoManagerHelper_Impl::undo( IMutexGuard& i_instanceLock )
 914     {
 915         impl_processRequest(
 916             [this, &i_instanceLock] () { return this->impl_doUndoRedo(i_instanceLock, true); },
 917             i_instanceLock
 918         );
 919     }
 920
 921     void UndoManagerHelper_Impl::redo( IMutexGuard& i_instanceLock )
 922     {
 923         impl_processRequest(
 924             [this, &i_instanceLock] () { return this->impl_doUndoRedo(i_instanceLock, false); },
 925             i_instanceLock
 926         );
 927     }
 928
 929     void UndoManagerHelper::addUndoAction( const Reference< XUndoAction >& i_action, IMutexGuard& i_instanceLock )
 930     {
 931         m_xImpl->addUndoAction( i_action, i_instanceLock );
 932     }
 933
 934     void UndoManagerHelper::undo( IMutexGuard& i_instanceLock )
 935     {
 936         m_xImpl->undo( i_instanceLock );
 937     }
 938
 939     void UndoManagerHelper::redo( IMutexGuard& i_instanceLock )
 940     {
 941         m_xImpl->redo( i_instanceLock );
 942     }
 943
 944     bool UndoManagerHelper::isUndoPossible() const
 945     {
 946         // SYNCHRONIZED --->
 947         ::osl::MutexGuard aGuard( m_xImpl->getMutex() );
 948         SfxUndoManager& rUndoManager = m_xImpl->getUndoManager();
 949         if ( rUndoManager.IsInListAction() )
 950             return false;
 951         return rUndoManager.GetUndoActionCount( SfxUndoManager::TopLevel ) > 0;
 952         // <--- SYNCHRONIZED
 953     }
 954
 955     bool UndoManagerHelper::isRedoPossible() const
 956     {
 957         // SYNCHRONIZED --->
 958         ::osl::MutexGuard aGuard( m_xImpl->getMutex() );
 959         const SfxUndoManager& rUndoManager = m_xImpl->getUndoManager();
 960         if ( rUndoManager.IsInListAction() )
 961             return false;
 962         return rUndoManager.GetRedoActionCount( SfxUndoManager::TopLevel ) > 0;
 963         // <--- SYNCHRONIZED
 964     }
 965
 966     namespace
 967     {
 968
 969         OUString lcl_getCurrentActionTitle( UndoManagerHelper_Impl& i_impl, const bool i_undo )
 970         {
 971             // SYNCHRONIZED --->
 972             ::osl::MutexGuard aGuard( i_impl.getMutex() );
 973
 974             const SfxUndoManager& rUndoManager = i_impl.getUndoManager();
 975             const size_t nActionCount = i_undo
 976                                     ?   rUndoManager.GetUndoActionCount( SfxUndoManager::TopLevel )
 977                                     :   rUndoManager.GetRedoActionCount( SfxUndoManager::TopLevel );
 978             if ( nActionCount == 0 )
 979                 throw EmptyUndoStackException(
 980                     i_undo ? u"no action on the undo stack"_ustr
 981                            : u"no action on the redo stack"_ustr,
 982                     i_impl.getXUndoManager()
 983                 );
 984             return  i_undo
 985                 ?   rUndoManager.GetUndoActionComment( 0, SfxUndoManager::TopLevel )
 986                 :   rUndoManager.GetRedoActionComment( 0, SfxUndoManager::TopLevel );
 987             // <--- SYNCHRONIZED
 988         }
 989
 990         Sequence< OUString > lcl_getAllActionTitles( UndoManagerHelper_Impl& i_impl, const bool i_undo )
 991         {
 992             // SYNCHRONIZED --->
 993             ::osl::MutexGuard aGuard( i_impl.getMutex() );
 994
 995             const SfxUndoManager& rUndoManager = i_impl.getUndoManager();
 996             const size_t nCount =   i_undo
 997                                 ?   rUndoManager.GetUndoActionCount( SfxUndoManager::TopLevel )
 998                                 :   rUndoManager.GetRedoActionCount( SfxUndoManager::TopLevel );
 999
1000             Sequence< OUString > aTitles( nCount );
1001             auto aTitlesRange = asNonConstRange(aTitles);
1002             for ( size_t i=0; i<nCount; ++i )
1003             {
1004                 aTitlesRange[i] =    i_undo
1005                             ?   rUndoManager.GetUndoActionComment( i, SfxUndoManager::TopLevel )
1006                             :   rUndoManager.GetRedoActionComment( i, SfxUndoManager::TopLevel );
1007             }
1008             return aTitles;
1009             // <--- SYNCHRONIZED
1010         }
1011     }
1012
1013     OUString UndoManagerHelper::getCurrentUndoActionTitle() const
1014     {
1015         return lcl_getCurrentActionTitle( *m_xImpl, true );
1016     }
1017
1018     OUString UndoManagerHelper::getCurrentRedoActionTitle() const
1019     {
1020         return lcl_getCurrentActionTitle( *m_xImpl, false );
1021     }
1022
1023     Sequence< OUString > UndoManagerHelper::getAllUndoActionTitles() const
1024     {
1025         return lcl_getAllActionTitles( *m_xImpl, true );
1026     }
1027
1028     Sequence< OUString > UndoManagerHelper::getAllRedoActionTitles() const
1029     {
1030         return lcl_getAllActionTitles( *m_xImpl, false );
1031     }
1032
1033     void UndoManagerHelper::clear( IMutexGuard& i_instanceLock )
1034     {
1035         m_xImpl->clear( i_instanceLock );
1036     }
1037
1038     void UndoManagerHelper::clearRedo( IMutexGuard& i_instanceLock )
1039     {
1040         m_xImpl->clearRedo( i_instanceLock );
1041     }
1042
1043     void UndoManagerHelper::reset( IMutexGuard& i_instanceLock )
1044     {
1045         m_xImpl->reset( i_instanceLock );
1046     }
1047
1048     void UndoManagerHelper::lock()
1049     {
1050         m_xImpl->lock();
1051     }
1052
1053     void UndoManagerHelper::unlock()
1054     {
1055         m_xImpl->unlock();
1056     }
1057
1058     bool UndoManagerHelper::isLocked()
1059     {
1060         // SYNCHRONIZED --->
1061         ::osl::MutexGuard aGuard( m_xImpl->getMutex() );
1062
1063         SfxUndoManager& rUndoManager = m_xImpl->getUndoManager();
1064         return !rUndoManager.IsUndoEnabled();
1065         // <--- SYNCHRONIZED
1066     }
1067
1068     void UndoManagerHelper::addUndoManagerListener( const Reference< XUndoManagerListener >& i_listener )
1069     {
1070         if ( i_listener.is() )
1071             m_xImpl->addUndoManagerListener( i_listener );
1072     }
1073
1074     void UndoManagerHelper::removeUndoManagerListener( const Reference< XUndoManagerListener >& i_listener )
1075     {
1076         if ( i_listener.is() )
1077             m_xImpl->removeUndoManagerListener( i_listener );
1078     }
1079
1080     void UndoManagerHelper::addModifyListener( const Reference< XModifyListener >& i_listener )
1081     {
1082         if ( i_listener.is() )
1083             m_xImpl->addModifyListener( i_listener );
1084     }
1085
1086     void UndoManagerHelper::removeModifyListener( const Reference< XModifyListener >& i_listener )
1087     {
1088         if ( i_listener.is() )
1089             m_xImpl->removeModifyListener( i_listener );
1090     }
1091
1092 } // namespace framework
1093
1094 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */