fix val_str_ascii to return a string in the ascii-compatible charset.

two items didn't do that properly, one was exploitable, the other was not, but fixed anyway.

mysql-test/r/ctype_utf32.result

@@ -1182,5 +1182,11 @@ a	256
 Warnings:
 Warning	1260	Row 1 was cut by GROUP_CONCAT()
 #
+# incorrect charset for val_str_ascii
+#
+SELECT '2010-10-10 10:10:10' + INTERVAL GeometryType(GeomFromText('POINT(1 1)')) hour_second;
+'2010-10-10 10:10:10' + INTERVAL GeometryType(GeomFromText('POINT(1 1)')) hour_second
+2010-10-10 10:10:10
+#
 # End of 5.5 tests
 #

mysql-test/t/ctype_utf32.test

@@ -854,6 +854,11 @@ SELECT 'a' AS id, REPEAT('bla bla', 100) AS body) t1
 GROUP BY id
 ORDER BY l DESC;
 
+--echo #
+--echo # incorrect charset for val_str_ascii
+--echo #
+
+SELECT '2010-10-10 10:10:10' + INTERVAL GeometryType(GeomFromText('POINT(1 1)')) hour_second;
 
 --echo #
 --echo # End of 5.5 tests

sql/item_geofunc.cc

@@ -135,6 +135,7 @@ String *Item_func_as_wkt::val_str_ascii(String *str)
     return 0;
 
   str->length(0);
+  str->set_charset(&my_charset_latin1);
   if ((null_value= geom->as_wkt(str, &dummy)))
     return 0;
 
@@ -182,7 +183,7 @@ String *Item_func_geometry_type::val_str_ascii(String *str)
   /* String will not move */
   str->copy(geom->get_class_info()->m_name.str,
 	    geom->get_class_info()->m_name.length,
-	    default_charset());
+            &my_charset_latin1);
   return str;
 }