Revert "Streamline singleton behavior in a class QgsSingleton"

This reverts commit e1f6edb as it breaks tests

src/core/CMakeLists.txt

@@ -557,7 +557,6 @@ SET(QGIS_CORE_HDRS
   qgssimplifymethod.h
   qgssnapper.h
   qgsspatialindex.h
-  qgssingleton.h
   qgstolerance.h
   qgsvectordataprovider.h
   qgsvectorlayercache.h

src/core/qgsapplication.cpp

@@ -14,13 +14,12 @@
  ***************************************************************************/
 
 #include "qgsapplication.h"
-#include "qgscrscache.h"
-#include "qgsexception.h"
-#include "qgsgeometry.h"
 #include "qgslogger.h"
 #include "qgsmaplayerregistry.h"
-#include "qgsnetworkaccessmanager.h"
 #include "qgsproviderregistry.h"
+#include "qgsnetworkaccessmanager.h"
+#include "qgsexception.h"
+#include "qgsgeometry.h"
 
 #include <QDir>
 #include <QFile>
@@ -608,13 +607,11 @@ void QgsApplication::initQgis()
 
 void QgsApplication::exitQgis()
 {
-  // Cleanup providers
+  delete QgsMapLayerRegistry::instance();
+
   delete QgsProviderRegistry::instance();
 
-  // Cleanup known singletons
-  QgsMapLayerRegistry::cleanup();
-  QgsNetworkAccessManager::cleanup();
-  QgsCoordinateTransformCache::cleanup();
+  delete QgsNetworkAccessManager::instance();
 }
 
 QString QgsApplication::showSettings()

src/core/qgscrscache.cpp

@@ -18,15 +18,20 @@
 #include "qgscrscache.h"
 #include "qgscoordinatetransform.h"
 
+
+QgsCoordinateTransformCache* QgsCoordinateTransformCache::instance()
+{
+  static QgsCoordinateTransformCache mInstance;
+  return &mInstance;
+}
+
 QgsCoordinateTransformCache::~QgsCoordinateTransformCache()
 {
   QHash< QPair< QString, QString >, QgsCoordinateTransform* >::const_iterator tIt = mTransforms.constBegin();
   for ( ; tIt != mTransforms.constEnd(); ++tIt )
   {
     delete tIt.value();
   }
-
-  mTransforms.clear();
 }
 
 const QgsCoordinateTransform* QgsCoordinateTransformCache::transform( const QString& srcAuthId, const QString& destAuthId, int srcDatumTransform, int destDatumTransform )

src/core/qgscrscache.h

@@ -19,16 +19,16 @@
 #define QGSCRSCACHE_H
 
 #include "qgscoordinatereferencesystem.h"
-#include "qgssingleton.h"
 #include <QHash>
 
 class QgsCoordinateTransform;
 
 /**Cache coordinate transform by authid of source/dest transformation to avoid the
 overhead of initialisation for each redraw*/
-class CORE_EXPORT QgsCoordinateTransformCache : public QgsSingleton<QgsCoordinateTransformCache>
+class CORE_EXPORT QgsCoordinateTransformCache
 {
   public:
+    static QgsCoordinateTransformCache* instance();
     ~QgsCoordinateTransformCache();
     /**Returns coordinate transformation. Cache keeps ownership
         @param srcAuthId auth id string of source crs
@@ -41,6 +41,7 @@ class CORE_EXPORT QgsCoordinateTransformCache : public QgsSingleton<QgsCoordinat
     void invalidateCrs( const QString& crsAuthId );
 
   private:
+    static QgsCoordinateTransformCache* mInstance;
     QMultiHash< QPair< QString, QString >, QgsCoordinateTransform* > mTransforms; //same auth_id pairs might have different datum transformations
 };
 

src/core/qgsmaplayerregistry.cpp

@@ -19,6 +19,19 @@
 #include "qgsmaplayer.h"
 #include "qgslogger.h"
 
+//
+// Static calls to enforce singleton behaviour
+//
+QgsMapLayerRegistry *QgsMapLayerRegistry::mInstance = 0;
+QgsMapLayerRegistry *QgsMapLayerRegistry::instance()
+{
+  if ( mInstance == 0 )
+  {
+    mInstance = new QgsMapLayerRegistry();
+  }
+  return mInstance;
+}
+
 //
 // Main class begins now...
 //

src/core/qgsmaplayerregistry.h

@@ -23,20 +23,21 @@
 #include <QSet>
 #include <QObject>
 #include <QStringList>
-
-#include "qgssingleton.h"
 class QString;
 class QgsMapLayer;
 
 /** \ingroup core
 * This class tracks map layers that are currently loaded and provides
 * a means to fetch a pointer to a map layer and delete it.
 */
-class CORE_EXPORT QgsMapLayerRegistry : public QObject, public QgsSingleton<QgsMapLayerRegistry>
+class CORE_EXPORT QgsMapLayerRegistry : public QObject
 {
     Q_OBJECT
 
   public:
+    //! Returns the instance pointer, creating the object on the first call
+    static QgsMapLayerRegistry * instance();
+
     //! Return the number of registered layers.
     int count();
 
@@ -238,10 +239,9 @@ class CORE_EXPORT QgsMapLayerRegistry : public QObject, public QgsSingleton<QgsM
     //! private singleton constructor
     QgsMapLayerRegistry( QObject * parent = 0 );
 
+    static QgsMapLayerRegistry *mInstance;
     QMap<QString, QgsMapLayer*> mMapLayers;
     QSet<QgsMapLayer*> mOwnedLayers;
-
-    friend class QgsSingleton; // Let QgsSingleton access private constructor
 }; // class QgsMapLayerRegistry
 
 #endif //QgsMapLayerRegistry_H

src/core/qgsnetworkaccessmanager.cpp

@@ -86,6 +86,19 @@ class QgsNetworkProxyFactory : public QNetworkProxyFactory
     }
 };
 
+//
+// Static calls to enforce singleton behaviour
+//
+QgsNetworkAccessManager* QgsNetworkAccessManager::sInstance = 0;
+QgsNetworkAccessManager* QgsNetworkAccessManager::instance()
+{
+  if ( sInstance == 0 )
+  {
+    sInstance = new QgsNetworkAccessManager();
+  }
+  return sInstance;
+}
+
 QgsNetworkAccessManager::QgsNetworkAccessManager( QObject *parent )
     : QNetworkAccessManager( parent )
     , mUseSystemProxy( false )

src/core/qgsnetworkaccessmanager.h

@@ -24,8 +24,6 @@
 #include <QNetworkProxy>
 #include <QNetworkRequest>
 
-#include "qgssingleton.h"
-
 /*
  * \class QgsNetworkAccessManager
  * \brief network access manager for QGIS
@@ -43,11 +41,15 @@
  * that the fallback proxy should not be used for, then no proxy will be used.
  *
  */
-class CORE_EXPORT QgsNetworkAccessManager : public QNetworkAccessManager, public QgsSingleton<QgsNetworkAccessManager>
+class CORE_EXPORT QgsNetworkAccessManager : public QNetworkAccessManager
 {
     Q_OBJECT
 
   public:
+    //! returns a pointer to the single instance
+    // and creates that instance on the first call.
+    static QgsNetworkAccessManager* instance();
+
     QgsNetworkAccessManager( QObject *parent = 0 );
 
     //! destructor
@@ -98,6 +100,7 @@ class CORE_EXPORT QgsNetworkAccessManager : public QNetworkAccessManager, public
     QNetworkProxy mFallbackProxy;
     QStringList mExcludedURLs;
     bool mUseSystemProxy;
+    static QgsNetworkAccessManager* sInstance;
 };
 
 #endif // QGSNETWORKACCESSMANAGER_H

src/core/qgsproviderregistry.cpp

@@ -208,7 +208,7 @@ QgsProviderRegistry::~QgsProviderRegistry()
 
   while ( it != mProviders.end() )
   {
-    QgsDebugMsg( QString( "cleanup: %1" ).arg( it->first ) );
+    QgsDebugMsg( QString( "cleanup:%1" ).arg( it->first ) );
     QString lib = it->second->library();
     QLibrary myLib( lib );
     if ( myLib.isLoaded() )
@@ -405,7 +405,7 @@ QWidget* QgsProviderRegistry::selectWidget( const QString & providerKey,
 
 #if QT_VERSION >= 0x050000
 QFunctionPointer QgsProviderRegistry::function( QString const & providerKey,
-    QString const & functionName )
+                                                QString const & functionName )
 {
   QLibrary myLib( library( providerKey ) );