Bug# 20730103 BACKPORT 19688008 TO 5.1

Problem: UDF doesn't handle the arguments properly when they
         are of string type due to a misplaced break.
         The length of arguments is also not set properly
         when the argument is NULL.

Solution: Fixed the code by putting the break at right place
          and setting the argument length to zero when the
          argument is NULL.

sql/item_func.cc

-/* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -3029,8 +3029,12 @@ bool udf_handler::get_arguments()
 	{
 	  f_args.args[i]=    (char*) res->ptr();
 	  f_args.lengths[i]= res->length();
-	  break;
 	}
+	else
+	{
+	  f_args.lengths[i]= 0;
+	}
+	break;
       }
     case INT_RESULT:
       *((longlong*) to) = args[i]->val_int();