[Shapelib - PATCH] Distinguish error case from empty intersection case in SHPSearchDiskTreeEx() and SBNSearchDiskTreeInteger()
|Reported by:||Even Rouault||Owned by:||warmerdam|
Currently, SHPSearchDiskTreeEx() and SBNSearchDiskTreeInteger() return a NULL pointer, if there was an error during the search or if the intersection is empty. Those are 2 different situations. The fix returns a non NULL pointer when the intersection is empty (with a count still at 0 of course).