Added GIS extension

BitKeeper/etc/ignore:
  Added myisam/rt_test myisam/sp_test to the ignore list

sql/item_cmpfunc.h

@@ -570,3 +570,82 @@ inline Item *and_conds(Item *a,Item *b)
     cond->update_used_tables();
   return cond;
 }
+
+
+/**************************************************************
+Spatial relations
+***************************************************************/
+
+class Item_func_spatial_rel :public Item_bool_func2
+{
+  enum Functype spatial_rel;
+public:
+  Item_func_spatial_rel(Item *a,Item *b, enum Functype sp_rel) :
+  	Item_bool_func2(a,b) { spatial_rel = sp_rel; }
+  longlong val_int();
+  enum Functype functype() const 
+  { 
+    switch (spatial_rel)
+    {
+      case SP_CONTAINS_FUNC:
+        return SP_WITHIN_FUNC;
+      case SP_WITHIN_FUNC:
+        return SP_CONTAINS_FUNC;
+      default:
+        return spatial_rel;
+    }
+  }
+  enum Functype rev_functype() const { return spatial_rel; }
+  const char *func_name() const 
+  { 
+    switch (spatial_rel)
+    {
+      case SP_CONTAINS_FUNC:
+        return "contains";
+      case SP_WITHIN_FUNC:
+        return "within";
+      case SP_EQUALS_FUNC:
+        return "equals";
+      case SP_DISJOINT_FUNC:
+        return "disjoint";
+      case SP_INTERSECTS_FUNC:
+        return "intersects";
+      case SP_TOUCHES_FUNC:
+        return "touches";
+      case SP_CROSSES_FUNC:
+        return "crosses";
+      case SP_OVERLAPS_FUNC:
+        return "overlaps";
+      default:
+        return "sp_unknown"; 
+    }
+  }
+};
+
+
+class Item_func_isempty :public Item_bool_func
+{
+public:
+  Item_func_isempty(Item *a) :Item_bool_func(a) {}
+  longlong val_int();
+  optimize_type select_optimize() const { return OPTIMIZE_NONE; }
+  const char *func_name() const { return "isempty"; }
+};
+
+class Item_func_issimple :public Item_bool_func
+{
+public:
+  Item_func_issimple(Item *a) :Item_bool_func(a) {}
+  longlong val_int();
+  optimize_type select_optimize() const { return OPTIMIZE_NONE; }
+  const char *func_name() const { return "issimple"; }
+};
+
+class Item_func_isclosed :public Item_bool_func
+{
+public:
+  Item_func_isclosed(Item *a) :Item_bool_func(a) {}
+  longlong val_int();
+  optimize_type select_optimize() const { return OPTIMIZE_NONE; }
+  const char *func_name() const { return "isclosed"; }
+};