Make geometry import/export more robust in case of invalid geometries. Fixes #12836

Author: mhugent

src/core/geometry/qgsgeometrycollectionv2.cpp

@@ -177,13 +177,24 @@ bool QgsGeometryCollectionV2::fromWkb( const unsigned char * wkb )
   wkbPtr >> mWkbType;
   int nGeometries = 0;
   wkbPtr >> nGeometries;
-  mGeometries.resize( nGeometries );
+
+  QList<QgsAbstractGeometryV2*> geometryList;
   for ( int i = 0; i < nGeometries; ++i )
   {
     QgsAbstractGeometryV2* geom = QgsGeometryImport::geomFromWkb( wkbPtr );
-    mGeometries[i] = geom;
-    wkbPtr += geom->wkbSize();
+    if ( geom )
+    {
+      geometryList.append( geom );
+      wkbPtr += geom->wkbSize();
+    }
+  }
+
+  mGeometries.resize( geometryList.size() );
+  for ( int i = 0; i < geometryList.size(); ++i )
+  {
+    mGeometries[i] = geometryList.at( i );
   }
+
   return true;
 }
 
@@ -198,7 +209,10 @@ int QgsGeometryCollectionV2::wkbSize() const
   int size = sizeof( char ) + sizeof( quint32 ) + sizeof( quint32 );
   foreach ( const QgsAbstractGeometryV2 *geom, mGeometries )
   {
-    size += geom->wkbSize();
+    if ( geom )
+    {
+      size += geom->wkbSize();
+    }
   }
   return size;
 }
@@ -214,10 +228,13 @@ unsigned char* QgsGeometryCollectionV2::asWkb( int& binarySize ) const
   foreach ( const QgsAbstractGeometryV2 *geom, mGeometries )
   {
     int geomWkbLen = 0;
-    unsigned char* geomWkb = geom->asWkb( geomWkbLen );
-    memcpy( wkb, geomWkb, geomWkbLen );
-    wkb += geomWkbLen;
-    delete[] geomWkb;
+    if ( geom )
+    {
+      unsigned char* geomWkb = geom->asWkb( geomWkbLen );
+      memcpy( wkb, geomWkb, geomWkbLen );
+      wkb += geomWkbLen;
+      delete[] geomWkb;
+    }
   }
   return geomPtr;
 }

src/core/geometry/qgsgeometryimport.cpp

@@ -21,6 +21,7 @@
 #include "qgscurvepolygonv2.h"
 #include "qgspointv2.h"
 #include "qgspolygonv2.h"
+#include "qgscurvepolygonv2.h"
 #include "qgslinestringv2.h"
 #include "qgsmulticurvev2.h"
 #include "qgsmultilinestringv2.h"
@@ -229,6 +230,12 @@ QgsAbstractGeometryV2* QgsGeometryImport::geomFromWkbType( QgsWKBTypes::Type t )
       return new QgsMultiPolygonV2();
     case QgsWKBTypes::MultiPoint:
       return new QgsMultiPointV2();
+    case QgsWKBTypes::MultiCurve:
+      return new QgsMultiCurveV2();
+    case QgsWKBTypes::MultiSurface:
+      return new QgsMultiSurfaceV2();
+    case QgsWKBTypes::GeometryCollection:
+      return new QgsGeometryCollectionV2();
     default:
       return 0;
   }

src/core/geometry/qgsgeos.cpp

@@ -1009,12 +1009,42 @@ GEOSGeometry* QgsGeos::asGeos( const QgsAbstractGeometryV2* geom )
     {
       return 0;
     }
-    GEOSGeometry **geomarr = new GEOSGeometry*[ c->numGeometries()];
-    for ( int i = 0; i < c->numGeometries(); ++i )
+
+    try
     {
-      geomarr[i] = asGeos( c->geometryN( i ) );
+
+      //GEOSGeometry **geomarr = new GEOSGeometry*[ c->numGeometries()];
+      QList< GEOSGeometry* > validGeoms;
+      GEOSGeometry* geosGeom = 0;
+      for ( int i = 0; i < c->numGeometries(); ++i )
+      {
+        geosGeom = asGeos( c->geometryN( i ) );
+        if ( geosGeom )
+        {
+          validGeoms.append( geosGeom );
+        }
+      }
+
+      if ( validGeoms.size() < 1 )
+      {
+        return 0;
+      }
+
+      GEOSGeometry **geomarr = new GEOSGeometry*[ validGeoms.size()];
+      for ( int i = 0; i < validGeoms.size(); ++i )
+      {
+        geomarr[i] = validGeoms.at( i );
+      }
+
+      return GEOSGeom_createCollection_r( geosinit.ctxt, geosType, geomarr, validGeoms.size() );
+    }
+
+    catch ( GEOSException &e )
+    {
+      Q_UNUSED( e );
+      //delete?
+      return 0;
     }
-    return GEOSGeom_createCollection_r( geosinit.ctxt, geosType, geomarr, c->numGeometries() ); //todo: geos exceptions
   }
 
   return 0;
@@ -1415,6 +1445,10 @@ GEOSGeometry* QgsGeos::createGeosPolygon( const QgsAbstractGeometryV2* poly )
     return 0;
 
   const QgsCurveV2* exteriorRing = polygon->exteriorRing();
+  if ( !exteriorRing )
+  {
+    return 0;
+  }
   GEOSGeometry* exteriorRingGeos = GEOSGeom_createLinearRing_r( geosinit.ctxt, createCoordinateSequence( exteriorRing ) );
 
   int nHoles = polygon->numInteriorRings();

src/core/geometry/qgspolygonv2.cpp

@@ -48,7 +48,12 @@ bool QgsPolygonV2::fromWkb( const unsigned char* wkb )
   {
     QgsLineStringV2* line = new QgsLineStringV2();
     line->fromWkbPoints( mWkbType, wkbPtr );
-    if ( i == 0 )
+    if ( !line->isRing() )
+    {
+      delete line; continue;
+    }
+
+    if ( !mExteriorRing )
     {
       mExteriorRing = line;
     }