From 60f7822a6e46af1b651260ca18472661f507cbdb Mon Sep 17 00:00:00 2001
From: wonder <wonder@c8812cc2-4d05-0410-92ff-de0c093fc19c>
Date: Fri, 10 Nov 2006 21:36:37 +0000
Subject: [PATCH] Fixed a crash occuring with identify tool which was caused by
 GEOS throwing TopologyException. This exception might be thrown when GEOS has
 problems with calculating intersection.

git-svn-id: http://svn.osgeo.org/qgis/trunk@6071 c8812cc2-4d05-0410-92ff-de0c093fc19c
---
 src/core/qgsgeometry.cpp             | 24 ++++++++++++++++++++----
 src/providers/ogr/qgsogrprovider.cpp | 15 ++++++++++++++-
 2 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/src/core/qgsgeometry.cpp b/src/core/qgsgeometry.cpp
index b4c7e26e4e7f..f3137bd99e6c 100644
--- a/src/core/qgsgeometry.cpp
+++ b/src/core/qgsgeometry.cpp
@@ -2076,9 +2076,17 @@ bool QgsGeometry::intersects(QgsRect* r) const
     rectwkt+="))";
     
     geos::Geometry *geosRect = wktReader->read( qstrdup(rectwkt) );
-    if(geosGeom->intersects(geosRect))
+    try // geos might throw exception on error
     {
-      returnval=true;
+      if(geosGeom->intersects(geosRect))
+      {
+        returnval=true;
+      }
+    }
+    catch (geos::TopologyException* e)
+    {
+      QString error = e->toString().c_str();
+      QgsLogger::warning("GEOS: " + error);
     }
  
     delete geosGeom;
@@ -2121,9 +2129,17 @@ bool QgsGeometry::fast_intersects(const QgsRect* r) const
     geos::WKTReader *wktReader = new geos::WKTReader(gf);
     geos::Geometry *geosRect = wktReader->read( qstrdup(rectwkt) );
     
-    if(geosGeom->intersects(geosRect))
+    try // geos might throw exception on error
+    {
+      if(geosGeom->intersects(geosRect))
+      {
+        returnval=true;
+      }
+    }
+    catch (geos::TopologyException* e)
     {
-      returnval=true;
+      QString error = e->toString().c_str();
+      QgsLogger::warning("GEOS: " + error);
     }
       
     delete geosGeom;
diff --git a/src/providers/ogr/qgsogrprovider.cpp b/src/providers/ogr/qgsogrprovider.cpp
index a8693df1095e..d7730d6e25c0 100644
--- a/src/providers/ogr/qgsogrprovider.cpp
+++ b/src/providers/ogr/qgsogrprovider.cpp
@@ -423,7 +423,20 @@ QgsFeature *QgsOgrProvider::getNextFeature(bool fetchAttributes)
 	       mSelectionRectangle->exportToWkt(&sWkt);  
 	       geos::Geometry *geosRect = wktReader->read(sWkt);
 	       assert(geosRect != 0);
-	       if(geosGeom->intersects(geosRect))
+         bool intersection = false;
+         
+         try // geos might throw exception on error
+         {
+           if(geosGeom->intersects(geosRect))
+             intersection = true;
+         }
+         catch (geos::TopologyException* e)
+         {
+           QString error = e->toString().c_str();
+           QgsLogger::warning("GEOS: " + error);
+         }
+         
+         if (intersection)
 	       {
 		   QgsDebugMsg("intersection found");
 		   delete[] sWkt;