------------------------------------------------------------------------------
--                                                                          --
--                 GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                 --
--                                                                          --
--                   A D A . E X C E P T I O N S . P O L L                  --
--       (version supporting asynchronous abort test and time slicing)      --
--                                                                          --
--                                  B o d y                                 --
--                                                                          --
--          Copyright (C) 1992-2005, Free Software Foundation, Inc.         --
--                                                                          --
-- GNARL is free software; you can  redistribute it  and/or modify it under --
-- terms of the  GNU General Public License as published  by the Free Soft- --
-- ware  Foundation;  either version 2,  or (at your option) any later ver- --
-- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
-- for  more details.  You should have  received  a copy of the GNU General --
-- Public License  distributed with GNARL; see file COPYING.  If not, write --
-- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
-- Boston, MA 02110-1301, USA.                                              --
--                                                                          --
-- As a special exception,  if other files  instantiate  generics from this --
-- unit, or you link  this unit with other files  to produce an executable, --
-- this  unit  does not  by itself cause  the resulting  executable  to  be --
-- covered  by the  GNU  General  Public  License.  This exception does not --
-- however invalidate  any other reasons why  the executable file  might be --
-- covered by the  GNU Public License.                                      --
--                                                                          --
-- GNARL was developed by the GNARL team at Florida State University.       --
-- Extensive contributions were provided by Ada Core Technologies, Inc.     --
--                                                                          --
------------------------------------------------------------------------------

--  This version is for targets that do not support per-thread asynchronous
--  signals or that do not handle async timers properly. On such targets, we
--  require compilation with the -gnatP switch that activates periodic polling.
--  Then in the body of the polling routine we test for asynchronous abort and
--  yield periodically.

--  This is currently used only by Interix

pragma Warnings (Off);
--  Allow withing of non-Preelaborated units in Ada 2005 mode where this
--  package will be categorized as Preelaborate. See AI-362 for details.
--  It is safe in the context of the run-time to violate the rules!

with System.Soft_Links;
--  used for Check_Abort_Status

pragma Warnings (On);

separate (Ada.Exceptions)

----------
-- Poll --
----------

procedure Poll is
begin
   if Counter = 10000 then
      Counter := 0;
      delay 0.0;
   else
      Counter := Counter + 1;
   end if;

   --  Test for asynchronous abort on each poll

   if System.Soft_Links.Check_Abort_Status.all /= 0 then
      raise Standard'Abort_Signal;
   end if;
end Poll;