/* * Copyright 2006-2007 Aaron Seigo * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Library General Public License as * published by the Free Software Foundation; either version 2, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details * * You should have received a copy of the GNU Library General Public * License along with this program; if not, write to the * Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include "dataenginemanager.h" #include #include namespace Plasma { class NullEngine : public DataEngine { public: NullEngine(QObject* parent = 0) : DataEngine(parent) { setObjectName(i18n("Null Engine")); setValid(false); // ref() ourselves to ensure we never get deleted ref(); } }; class DataEngineManager::Private { public: Private() : nullEng(0) {} ~Private() { foreach (Plasma::DataEngine* engine, engines) { delete engine; } engines.clear(); delete nullEng; } DataEngine* nullEngine() { if (!nullEng) { nullEng = new NullEngine; } return nullEng; } DataEngine::Dict engines; DataEngine* nullEng; }; class DataEngineManagerSingleton { public: DataEngineManager self; }; K_GLOBAL_STATIC(DataEngineManagerSingleton, privateDataEngineManagerSelf) DataEngineManager* DataEngineManager::self() { return &privateDataEngineManagerSelf->self; } DataEngineManager::DataEngineManager() : d(new Private()) { } DataEngineManager::~DataEngineManager() { delete d; } Plasma::DataEngine* DataEngineManager::dataEngine(const QString& name) const { Plasma::DataEngine::Dict::const_iterator it = d->engines.find(name); if (it != d->engines.end()) { // ref and return the engine //Plasma::DataEngine *engine = *it; return *it; } return d->nullEngine(); } Plasma::DataEngine* DataEngineManager::loadDataEngine(const QString& name) { Plasma::DataEngine* engine = 0; Plasma::DataEngine::Dict::const_iterator it = d->engines.find(name); if (it != d->engines.end()) { engine = *it; engine->ref(); return engine; } // load the engine, add it to the engines QString constraint = QString("[X-EngineName] == '%1'").arg(name); KService::List offers = KServiceTypeTrader::self()->query("Plasma/DataEngine", constraint); QString error; if (offers.isEmpty()) { kDebug() << "offers are empty for " << name << " with constraint " << constraint; } else { engine = KService::createInstance(offers.first(), 0, QVariantList(), &error); } if (!engine) { kDebug() << "Couldn't load engine \"" << name << "\". Error given: " << error; return d->nullEngine(); } engine->ref(); engine->setObjectName(offers.first()->name()); engine->setIcon(offers.first()->icon()); d->engines[name] = engine; return engine; } void DataEngineManager::unloadDataEngine(const QString& name) { Plasma::DataEngine::Dict::iterator it = d->engines.find(name); if (it != d->engines.end()) { Plasma::DataEngine* engine = *it; engine->deref(); if (!engine->isUsed()) { d->engines.erase(it); delete engine; } } } QStringList DataEngineManager::knownEngines() { QStringList engines; KService::List offers = KServiceTypeTrader::self()->query("Plasma/DataEngine"); foreach (KService::Ptr service, offers) { engines.append(service->property("X-EngineName").toString()); } return engines; } } // namespace Plasma #include "dataenginemanager.moc"