mapscript crashes on getFeature

[Umberto Nicoletti]

I suggest that Query.java be incorporated in mapserver source
distribution (with author's permission, of course) as it will help in
spot similar errors in future: it will work as a kind of test suite,
even if in fact it is not a proper test suite.

Best regards,
Umberto

On 11/16/05, Donovan <donovan at functionfour.ca> wrote:
> >You've got my attention. Donovan do you have any more specific information
> regarding the GEOS crash?   --Steve
>
> Sure,
>
> I'm using mapserver 4.8.0beta - but 4.6.0 breaks too
> --geos-2.1.1 from rpm (gdal-1.2.6 and proj-4.4.9 also)
> --FedoraCore3 with java1.5 (glibc-2.3.5)
>
> I think the crash occurs any time a shapeObj is returned.
>
> I modified the java mapscript example class DrawMap from the mapserver
> source tree to demonstrate the problem - Query.java is attached.
>
> Without GEOS, Query.java generates the png but with GEOS, it looks like this:
> # cd ~/mapserver-4.8.0-beta1/mapscript/java
> # javac -classpath ./:examples/:./mapscript.jar -d examples/ examples/*.java
> # java -classpath ./:examples/:./mapscript.jar -Djava.library.path=. Query
> ../../tests/test.map ./map.png
>
> > The map will be drawn to:./map.png
> > *** glibc detected *** malloc(): memory corruption: 0xb1c11ee8 ***
> > Aborted
>
> From poking around in the source i think the crash happens while freeing the
> geometry pointer in the shape obj but i didn't get any further.
>
> If there is anything else i can provide or if some testing is required i'd
> be happy to help...
>
> Thanks for your attention
>
>
> ----mapscript/java/examples/Query.java----cut-here--
> import edu.umn.gis.mapscript.*;
>
> public class Query {
>
>   public static void usage() {
>     System.err.println("Usage: Query {mapfile} {outfile}");
>     System.exit(-1);
>   }
>
>   public static void main(String[] args) {
>     if (args.length != 2) usage();
>         try
>         {
>           System.loadLibrary("mapscript");
>         }
>         catch(UnsatisfiedLinkError ule)
>         {
>           System.err.println(ule);
>           System.exit(-1);
>         }
>
>     mapObj map = new mapObj(args[0]);
>     map.getImagecolor().setRGB(153, 153, 204);
>     styleObj st = map.getLayer(1).getClass(0).getStyle(0);
>     st.getColor().setHex("#000000");
>     imageObj img = map.draw();
>     System.out.println("The map will be drawn to:"+args[1]);
>
>     layerObj layer = map.getLayerByName("POLYGON");
>     layer.setTemplate("dummy.template");
>     layer.queryByPoint(map,new pointObj(0.10,51.4,0),
>         mapscriptConstants.MS_MULTIPLE,-1);
>     resultCacheObj results = layer.getResults();
>     layer.open();
>     for (int i=0;i<results.getNumresults();i++) {
>        resultCacheMemberObj result = results.getResult(i);
>        //CRASH HAPPENS ON NEXT LINE
>        shapeObj feature = layer.getFeature(result.getShapeindex(),-1);
>     }
>     layer.close();
>
>     img.save(args[1], map);
>   }
> }
> -----End of Query.java----------
>