ImageManager/RequestQueue.cpp

   1 /* Copyright (C) 2003-2006 Jesper K. Pedersen <blackie@kde.org>
   2
   3    This program is free software; you can redistribute it and/or
   4    modify it under the terms of the GNU General Public
   5    License as published by the Free Software Foundation; either
   6    version 2 of the License, or (at your option) any later version.
   7
   8    This program is distributed in the hope that it will be useful,
   9    but WITHOUT ANY WARRANTY; without even the implied warranty of
  10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11    General Public License for more details.
  12
  13    You should have received a copy of the GNU General Public License
  14    along with this program; see the file COPYING.  If not, write to
  15    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  16    Boston, MA 02110-1301, USA.
  17 */
  18 #include "RequestQueue.h"
  19 #include "ImageRequest.h"
  20
  21 bool ImageManager::RequestQueue::addRequest( ImageRequest* request )
  22 {
  23     if ( _uniquePending.contains( request ) ) {
  24         // We have this very same request already in the queue. Ignore this one.
  25         delete request;
  26         return false;
  27     }
  28
  29     _queues[ request->priority() ].enqueue( request );
  30     _uniquePending.insert( request );
  31
  32     if ( request->client() )
  33         _activeRequests.insert( request );
  34
  35     return true;
  36 }
  37
  38 ImageManager::ImageRequest* ImageManager::RequestQueue::popNext()
  39 {
  40     QueueType::iterator it = _queues.end(); // _queues is initialized to non-zero size
  41     do {
  42         --it;
  43         while ( ! it->empty() ) {
  44             ImageRequest* request = it->dequeue();
  45
  46             if ( ! request->stillNeeded() ) {
  47                 removeRequest( request );
  48                 delete request;
  49             } else {
  50                 _uniquePending.remove( request );
  51                 return request;
  52             }
  53         }
  54     } while ( it != _queues.begin() );
  55
  56     return NULL;
  57 }
  58
  59 void ImageManager::RequestQueue::cancelRequests( ImageClient* client, StopAction action )
  60 {
  61     // remove from active map
  62     for( QSet<ImageRequest*>::const_iterator it = _activeRequests.begin(); it != _activeRequests.end(); ) {
  63         ImageRequest* request = *it;
  64         ++it; // We need to increase it before removing the element.
  65         if ( client == request->client() && ( action == StopAll || ( request->priority() < ThumbnailVisible ) ) ) {
  66             _activeRequests.remove( request );
  67             // active requests are not deleted - they might already have been
  68             // popNext()ed and are being processed. They will be deleted
  69             // in Manger::customEvent().
  70         }
  71     }
  72
  73     for ( QueueType::iterator qit = _queues.begin(); qit != _queues.end(); ++qit ) {
  74         for ( QQueue<ImageRequest*>::iterator it = qit->begin(); it != qit->end(); /* no increment here */) {
  75             ImageRequest* request = *it;
  76             if ( request->client() == client && ( action == StopAll || request->priority() < ThumbnailVisible ) ) {
  77                 it = qit->erase( it );
  78                 _uniquePending.remove( request );
  79                 delete request;
  80             } else {
  81                 ++it;
  82             }
  83         }
  84     }
  85 }
  86
  87 bool ImageManager::RequestQueue::isRequestStillValid( ImageRequest* request )
  88 {
  89     return _activeRequests.contains( request );
  90 }
  91
  92 void ImageManager::RequestQueue::removeRequest( ImageRequest* request )
  93 {
  94     _activeRequests.remove( request );
  95     _uniquePending.remove( request );
  96 }
  97
  98 ImageManager::RequestQueue::RequestQueue()
  99 {
 100     for ( int i = 0; i < LastPriority; ++i )
 101         _queues.append( QQueue<ImageRequest*>() );
 102 }
 103
 104
 105 #include "RequestQueue.moc"