Merge branch 'iterator'

Semi fix #7472.
Semi fix #7862

Author: NathanW2

src/providers/ogr/qgsogrfeatureiterator.cpp

@@ -32,17 +32,31 @@
 
 
 QgsOgrFeatureIterator::QgsOgrFeatureIterator( QgsOgrProvider* p, const QgsFeatureRequest& request )
-    : QgsAbstractFeatureIterator( request ), P( p )
+  : QgsAbstractFeatureIterator( request ), P( p ), ogrDataSource(0), ogrLayer(0), mSubsetStringSet(false)
 {
-  // make sure that only one iterator is active
-  if ( P->mActiveIterator )
+  mFeatureFetched = false;
+  P->mActiveIterators.insert( this );
+
+  ogrDataSource = OGROpen( TO8F( P->filePath() ), false, NULL );
+
+  if ( P->layerName().isNull() )
   {
-    QgsMessageLog::logMessage( QObject::tr( "Already active iterator on this provider was closed." ), QObject::tr( "OGR" ) );
-    P->mActiveIterator->close();
+    ogrLayer = OGR_DS_GetLayer( ogrDataSource, P->layerIndex() );
+  }
+  else
+  {
+    ogrLayer = OGR_DS_GetLayerByName( ogrDataSource, TO8( p->layerName() ) );
   }
-  P->mActiveIterator = this;
 
-  mFeatureFetched = false;
+  if ( !P->subsetString().isEmpty() )
+  {
+      QString sql = QString( "SELECT * FROM %1 WHERE %2" )
+                    .arg( P->quotedIdentifier( FROM8( OGR_FD_GetName( OGR_L_GetLayerDefn( ogrLayer ) ) ) ) )
+                    .arg( P->subsetString() );
+      QgsDebugMsg( QString( "SQL: %1" ).arg( sql ) );
+      ogrLayer = OGR_DS_ExecuteSQL( ogrDataSource, P->textEncoding()->fromUnicode( sql ).constData(), NULL, NULL );
+      mSubsetStringSet = true;
+  }
 
   ensureRelevantFields();
 
@@ -56,12 +70,12 @@ QgsOgrFeatureIterator::QgsOgrFeatureIterator( QgsOgrProvider* p, const QgsFeatur
 
     OGR_G_CreateFromWkt(( char ** )&wktText, NULL, &filter );
     QgsDebugMsg( "Setting spatial filter using " + wktExtent );
-    OGR_L_SetSpatialFilter( P->ogrLayer, filter );
+    OGR_L_SetSpatialFilter( ogrLayer, filter );
     OGR_G_DestroyGeometry( filter );
   }
   else
   {
-    OGR_L_SetSpatialFilter( P->ogrLayer, 0 );
+    OGR_L_SetSpatialFilter( ogrLayer, 0 );
   }
 
   //start with first feature
@@ -94,7 +108,7 @@ bool QgsOgrFeatureIterator::nextFeature( QgsFeature& feature )
 
   if ( mRequest.filterType() == QgsFeatureRequest::FilterFid )
   {
-    OGRFeatureH fet = OGR_L_GetFeature( P->ogrLayer, FID_TO_NUMBER( mRequest.filterFid() ) );
+    OGRFeatureH fet = OGR_L_GetFeature( ogrLayer, FID_TO_NUMBER( mRequest.filterFid() ) );
     if ( !fet )
     {
       close();
@@ -111,7 +125,7 @@ bool QgsOgrFeatureIterator::nextFeature( QgsFeature& feature )
 
   OGRFeatureH fet;
 
-  while (( fet = OGR_L_GetNextFeature( P->ogrLayer ) ) )
+  while (( fet = OGR_L_GetNextFeature( ogrLayer ) ) )
   {
     if ( !readFeature( fet, feature ) )
       continue;
@@ -135,7 +149,7 @@ bool QgsOgrFeatureIterator::rewind()
   if ( mClosed )
     return false;
 
-  OGR_L_ResetReading( P->ogrLayer );
+  OGR_L_ResetReading( ogrLayer );
 
   return true;
 }
@@ -146,10 +160,17 @@ bool QgsOgrFeatureIterator::close()
   if ( mClosed )
     return false;
 
-  // tell provider that this iterator is not active anymore
-  P->mActiveIterator = 0;
+  P->mActiveIterators.remove( this );
+
+  if (mSubsetStringSet)
+  {
+    OGR_DS_ReleaseResultSet(ogrDataSource, ogrLayer );
+  }
+
+  OGR_DS_Destroy( ogrDataSource );
 
   mClosed = true;
+  ogrDataSource = 0;
   return true;
 }
 

src/providers/ogr/qgsogrfeatureiterator.h

@@ -48,6 +48,11 @@ class QgsOgrFeatureIterator : public QgsAbstractFeatureIterator
     void getFeatureAttribute( OGRFeatureH ogrFet, QgsFeature & f, int attindex );
 
     bool mFeatureFetched;
+
+    OGRDataSourceH ogrDataSource;
+    OGRLayerH ogrLayer;
+
+    bool mSubsetStringSet;
 };
 
 

src/providers/ogr/qgsogrprovider.cpp

@@ -209,7 +209,6 @@ QgsOgrProvider::QgsOgrProvider( QString const & uri )
     , ogrDriver( 0 )
     , valid( false )
     , featuresCounted( -1 )
-    , mActiveIterator( 0 )
 {
   QgsCPLErrorHandler handler;
 
@@ -360,8 +359,12 @@ QgsOgrProvider::QgsOgrProvider( QString const & uri )
 
 QgsOgrProvider::~QgsOgrProvider()
 {
-  if ( mActiveIterator )
-    mActiveIterator->close();
+  // Do we need to close all active iterators here?
+
+  foreach ( QgsOgrFeatureIterator* it, mActiveIterators )
+  {
+    it->close();
+  }
 
   if ( ogrLayer != ogrOrigLayer )
   {

src/providers/ogr/qgsogrprovider.h

@@ -15,6 +15,8 @@ email                : sherman at mrcc.com
  *                                                                         *
  ***************************************************************************/
 
+#include "QTextCodec"
+
 #include "qgsrectangle.h"
 #include "qgsvectordataprovider.h"
 #include "qgsvectorfilewriter.h"
@@ -250,6 +252,16 @@ class QgsOgrProvider : public QgsVectorDataProvider
     /** Get single flatten geometry type */
     static OGRwkbGeometryType ogrWkbSingleFlatten( OGRwkbGeometryType type );
 
+    QString layerName() { return mLayerName; }
+
+    QString filePath() { return mFilePath; }
+
+    int layerIndex() { return mLayerIndex; }
+
+    QTextCodec* textEncoding() { return mEncoding; }
+
+    QString quotedIdentifier( QString field );
+
   protected:
     /** loads fields from input file to member attributeFields */
     void loadFields();
@@ -323,11 +335,9 @@ class QgsOgrProvider : public QgsVectorDataProvider
     /**Deletes one feature*/
     bool deleteFeature( QgsFeatureId id );
 
-    QString quotedIdentifier( QString field );
-
     /**Calls OGR_L_SyncToDisk and recreates the spatial index if present*/
     bool syncToDisc();
 
     friend class QgsOgrFeatureIterator;
-    QgsOgrFeatureIterator* mActiveIterator; //!< pointer to currently active iterator (0 if none)
+    QSet< QgsOgrFeatureIterator*> mActiveIterators;
 };