xref: /AOO41X/main/comphelper/source/misc/accessibleeventnotifier.cxx (revision dde7d3faf6dcd9cbeb7b48ba6d0cea5ffcc883d0)
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21 
22 
23 
24 // MARKER(update_precomp.py): autogen include statement, do not remove
25 #include "precompiled_comphelper.hxx"
26 #include <comphelper/accessibleeventnotifier.hxx>
27 #include <osl/diagnose.h>
28 #include <rtl/instance.hxx>
29 #include <comphelper/guarding.hxx>
30 
31 using namespace ::com::sun::star::uno;
32 using namespace ::com::sun::star::lang;
33 using namespace ::com::sun::star::accessibility;
34 using namespace ::comphelper;
35 
36 //=====================================================================
37 //= AccessibleEventNotifier
38 //=====================================================================
39 //---------------------------------------------------------------------
40 namespace
41 {
42     struct lclMutex
43         : public rtl::Static< ::osl::Mutex, lclMutex > {};
44     struct Clients
45         : public rtl::Static< AccessibleEventNotifier::ClientMap, Clients > {};
46 }
47 
48 //.........................................................................
49 namespace comphelper
50 {
51 //.........................................................................
52 
53     //---------------------------------------------------------------------
generateId()54     AccessibleEventNotifier::TClientId AccessibleEventNotifier::generateId()
55     {
56         TClientId nBiggestUsedId = 0;
57         TClientId nFreeId = 0;
58 
59         // look through all registered clients until we find a "gap" in the ids
60 
61         // Note that the following relies on the fact the elements in the map are traveled with
62         // ascending keys (aka client ids)
63         AccessibleEventNotifier::ClientMap &rClients = Clients::get();
64         for (   ClientMap::const_iterator aLookup = rClients.begin();
65                 aLookup != rClients.end();
66                 ++aLookup
67             )
68         {
69             TClientId nCurrent = aLookup->first;
70             OSL_ENSURE( nCurrent > nBiggestUsedId, "AccessibleEventNotifier::generateId: map is expected to be sorted ascending!" );
71 
72             if ( nCurrent - nBiggestUsedId > 1 )
73             {   // found a "gap"
74                 nFreeId = nBiggestUsedId + 1;
75                 break;
76             }
77 
78             nBiggestUsedId = nCurrent;
79         }
80 
81         if ( !nFreeId )
82             nFreeId = nBiggestUsedId + 1;
83 
84         OSL_ENSURE( rClients.end() == rClients.find( nFreeId ),
85             "AccessibleEventNotifier::generateId: algorithm broken!" );
86 
87         return nFreeId;
88     }
89 
90     //---------------------------------------------------------------------
registerClient()91     AccessibleEventNotifier::TClientId AccessibleEventNotifier::registerClient( )
92     {
93         ::osl::MutexGuard aGuard( lclMutex::get() );
94 
95         // generate a new client id
96         TClientId nNewClientId = generateId( );
97 
98         // the event listeners for the new client
99         EventListeners* pNewListeners = new EventListeners( lclMutex::get() );
100             // note that we're using our own mutex here, so the listener containers for all
101             // our clients share this same mutex.
102             // this is a reminiscense to the days where the notifier was asynchronous. Today this is
103             // completely nonsense, and potentially slowing down the Office me thinks ...
104 
105         // add the client
106         Clients::get().insert( ClientMap::value_type( nNewClientId, pNewListeners ) );
107 
108         // outta here
109         return nNewClientId;
110     }
111 
112     //---------------------------------------------------------------------
implLookupClient(const TClientId _nClient,ClientMap::iterator & _rPos)113     sal_Bool AccessibleEventNotifier::implLookupClient( const TClientId _nClient, ClientMap::iterator& _rPos )
114     {
115         // look up this client
116         AccessibleEventNotifier::ClientMap &rClients = Clients::get();
117         _rPos = rClients.find( _nClient );
118         OSL_ENSURE( rClients.end() != _rPos, "AccessibleEventNotifier::implLookupClient: invalid client id (did you register your client?)!" );
119 
120         return ( rClients.end() != _rPos );
121     }
122 
123     //---------------------------------------------------------------------
revokeClient(const TClientId _nClient)124     void AccessibleEventNotifier::revokeClient( const TClientId _nClient )
125     {
126         ::osl::MutexGuard aGuard( lclMutex::get() );
127 
128         ClientMap::iterator aClientPos;
129         if ( !implLookupClient( _nClient, aClientPos ) )
130             // already asserted in implLookupClient
131             return;
132 
133         // remove it from the clients map
134         delete aClientPos->second;
135         Clients::get().erase( aClientPos );
136     }
137 
138     //---------------------------------------------------------------------
revokeClientNotifyDisposing(const TClientId _nClient,const Reference<XInterface> & _rxEventSource)139     void AccessibleEventNotifier::revokeClientNotifyDisposing( const TClientId _nClient,
140             const Reference< XInterface >& _rxEventSource ) SAL_THROW( ( ) )
141     {
142         ::osl::MutexGuard aGuard( lclMutex::get() );
143 
144         ClientMap::iterator aClientPos;
145         if ( !implLookupClient( _nClient, aClientPos ) )
146             // already asserted in implLookupClient
147             return;
148 
149         // notify the "disposing" event for this client
150         EventObject aDisposalEvent;
151         aDisposalEvent.Source = _rxEventSource;
152 
153         // notify the listeners
154         EventListeners* pListeners = aClientPos->second;
155 
156         // we do not need the entry in the clients map anymore
157         // (do this before actually notifying, because some client implementations have re-entrance
158         // problems and call into revokeClient while we are notifying from hereing)
159         Clients::get().erase( aClientPos );
160 
161         // now really do the notification
162         pListeners->disposeAndClear( aDisposalEvent );
163         delete pListeners;
164 
165     }
166 
167     //---------------------------------------------------------------------
addEventListener(const TClientId _nClient,const Reference<XAccessibleEventListener> & _rxListener)168     sal_Int32 AccessibleEventNotifier::addEventListener(
169         const TClientId _nClient, const Reference< XAccessibleEventListener >& _rxListener ) SAL_THROW( ( ) )
170     {
171         ::osl::MutexGuard aGuard( lclMutex::get() );
172 
173         ClientMap::iterator aClientPos;
174         if ( !implLookupClient( _nClient, aClientPos ) )
175             // already asserted in implLookupClient
176             return 0;
177 
178         if ( _rxListener.is() )
179             aClientPos->second->addInterface( _rxListener );
180 
181         return aClientPos->second->getLength();
182     }
183 
184     //---------------------------------------------------------------------
removeEventListener(const TClientId _nClient,const Reference<XAccessibleEventListener> & _rxListener)185     sal_Int32 AccessibleEventNotifier::removeEventListener(
186         const TClientId _nClient, const Reference< XAccessibleEventListener >& _rxListener ) SAL_THROW( ( ) )
187     {
188         ::osl::MutexGuard aGuard( lclMutex::get() );
189 
190         ClientMap::iterator aClientPos;
191         if ( !implLookupClient( _nClient, aClientPos ) )
192             // already asserted in implLookupClient
193             return 0;
194 
195         if ( _rxListener.is() )
196             aClientPos->second->removeInterface( _rxListener );
197 
198         return aClientPos->second->getLength();
199     }
200 
201     //---------------------------------------------------------------------
getEventListeners(const TClientId _nClient)202     Sequence< Reference< XInterface > > AccessibleEventNotifier::getEventListeners( const TClientId _nClient ) SAL_THROW( ( ) )
203     {
204         Sequence< Reference< XInterface > > aListeners;
205 
206         ::osl::MutexGuard aGuard( lclMutex::get() );
207 
208         ClientMap::iterator aClientPos;
209         if ( implLookupClient( _nClient, aClientPos ) )
210             aListeners = aClientPos->second->getElements();
211 
212         return aListeners;
213     }
214 
215     //---------------------------------------------------------------------
addEvent(const TClientId _nClient,const AccessibleEventObject & _rEvent)216     void AccessibleEventNotifier::addEvent( const TClientId _nClient, const AccessibleEventObject& _rEvent ) SAL_THROW( ( ) )
217     {
218         Sequence< Reference< XInterface > > aListeners;
219 
220         // --- <mutex lock> -------------------------------
221         {
222             ::osl::MutexGuard aGuard( lclMutex::get() );
223 
224             ClientMap::iterator aClientPos;
225             if ( !implLookupClient( _nClient, aClientPos ) )
226                 // already asserted in implLookupClient
227                 return;
228 
229             // since we're synchronous, again, we want to notify immediately
230             aListeners = aClientPos->second->getElements();
231         }
232         // --- </mutex lock> ------------------------------
233 
234             // default handling: loop through all listeners, and notify them
235         const Reference< XInterface >* pListeners = aListeners.getConstArray();
236         const Reference< XInterface >* pListenersEnd = pListeners + aListeners.getLength();
237         while ( pListeners != pListenersEnd )
238         {
239             try
240             {
241                 static_cast< XAccessibleEventListener* >( pListeners->get() )->notifyEvent( _rEvent );
242             }
243             catch( const Exception& )
244             {
245                 // no assertion, because a broken access remote bridge or something like this
246                 // can cause this exception
247             }
248             ++pListeners;
249         }
250     }
251 
252 //.........................................................................
253 }   // namespace comphelper
254 //.........................................................................
255 
256