c974009.a

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-- C974009.A
--
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--     Under contracts F33600-87-D-0337, F33600-84-D-0280, MDA903-79-C-0687,
--     F08630-91-C-0015, and DCA100-97-D-0025, the U.S. Government obtained 
--     unlimited rights in the software and documentation contained herein.
--     Unlimited rights are defined in DFAR 252.227-7013(a)(19).  By making 
--     this public release, the Government intends to confer upon all 
--     recipients unlimited rights  equal to those held by the Government.  
--     These rights include rights to use, duplicate, release or disclose the 
--     released technical data and computer software in whole or in part, in 
--     any manner and for any purpose whatsoever, and to have or permit others 
--     to do so.
--
--                                    DISCLAIMER
--
--     ALL MATERIALS OR INFORMATION HEREIN RELEASED, MADE AVAILABLE OR
--     DISCLOSED ARE AS IS.  THE GOVERNMENT MAKES NO EXPRESS OR IMPLIED 
--     WARRANTY AS TO ANY MATTER WHATSOEVER, INCLUDING THE CONDITIONS OF THE
--     SOFTWARE, DOCUMENTATION OR OTHER INFORMATION RELEASED, MADE AVAILABLE 
--     OR DISCLOSED, OR THE OWNERSHIP, MERCHANTABILITY, OR FITNESS FOR A
--     PARTICULAR PURPOSE OF SAID MATERIAL.
--*
--
-- OBJECTIVE:
--      Check that the abortable part of an asynchronous select statement
--      is not started if the triggering statement is a task entry call, 
--      the entry call is not queued and the entry call completes by 
--      propagating an exception.
--
--      Check that the exception is properly propagated to the asynchronous
--      select statement and thus the sequence of statements of the triggering
--      alternative is not executed after the abortable part is left. 
--
--      Check that the exception propagated by the entry call is re-raised
--      immediately following the asynchronous select.
--
-- TEST DESCRIPTION:
--
--      Use a small subset of the base Automated teller machine simulation
--      which is shown in greater detail in other tests of this series.  
--      Declare a main procedure containing an asynchronous select with a task
--      entry call as triggering statement.  Force the task to be waiting at
--      the accept statement so that the call is not queued and the rendezvous
--      is executed immediately.  Simulate an unexpected exception in the
--      rendezvous. Use stripped down versions of called procedures to  check
--      the correct path in the test.
--
--
-- CHANGE HISTORY:
--      06 Dec 94   SAIC    ACVC 2.0
--
--!


package C974009_0 is  -- Automated teller machine abstraction.


   Propagated_From_Task : exception;
   Transaction_Canceled : exception;

   type Key_Enum is (None, Cancel, Deposit, Withdraw);

   type Card_Number_Type is private;
   type Card_PIN_Type    is private;
   type ATM_Card_Type    is private;

   task type ATM_Keyboard_Task is
      entry Cancel_Pressed;
   end ATM_Keyboard_Task;


   procedure Validate_Card (Card : in ATM_Card_Type);

   procedure Perform_Transaction (Card : in ATM_Card_Type);


private

   type Card_Number_Type is range   1 .. 9999;
   type Card_PIN_Type    is range 100 ..  999;

   type ATM_Card_Type is record
      Number : Card_Number_Type;
      PIN    : Card_PIN_Type;
   end record;

end C974009_0;


     --==================================================================--


with Report;
package body C974009_0 is



   -- One of these gets created as "Keyboard" for each transaction
   --
   task body ATM_Keyboard_Task is
      Key_Pressed : Key_Enum := None;
   begin
      accept Cancel_Pressed do        -- queued entry call.
         null;  --:::: stub, user code for cancel
         -- Now simulate an unexpected exception arising in the
         -- user code
         raise Propagated_From_Task;  -- Propagate an exception.
                  
       end Cancel_Pressed;

       Report.Failed ("Exception not propagated in ATM_Keyboard_Task");
               
   exception
      when Propagated_From_Task =>
          null;  -- This is the expected test behavior
      when others =>
          Report.Failed ("Unexpected Exception in ATM_Keyboard_Task");
   end ATM_Keyboard_Task;

   procedure Validate_Card (Card : in ATM_Card_Type) is
   begin
      Report.Failed ("Abortable part was executed");
   end Validate_Card;


   procedure Perform_Transaction (Card : in ATM_Card_Type) is
   begin
      Report.Failed ("Exception not re-raised immediately following " &
                     "asynchronous select");
   end Perform_Transaction;


end C974009_0;


     --==================================================================--


with Report;
with ImpDef;

with C974009_0;  -- Automated teller machine abstraction.
use  C974009_0;

procedure C974009 is

   Card_Data : ATM_Card_Type;

begin  -- Main program.

   Report.Test ("C974009", "Asynchronous Select: Trigger is a call to a " &
                           "task entry, is not queued and is completed " &
                           "first by an exception");


   begin

      declare
         -- Create the task for this transaction
         Keyboard : C974009_0.ATM_Keyboard_Task;
      begin

         -- Ensure task is waiting a the accept so the call is not queued
         -- This is the time required to activate another task and allow it
         -- to run to its first accept statement
         -- 
         delay ImpDef.Switch_To_New_Task;

         --                                    --
         -- Asynchronous select is tested here --
         --                                    --

         select
 
            Keyboard.Cancel_Pressed;

            raise Transaction_Canceled;  -- Should not be executed.
         then abort
            Validate_Card (Card_Data);   -- Keyboard.Cancel_Pressed is accepted
                                         -- and propagates an exception before
                                         -- this call is executed
         end select;

         -- The propagated exception is re-raised here.
         Perform_Transaction(Card_Data); -- Should not be reached.

      exception
         when Transaction_Canceled =>
            Report.Failed ("Triggering alternative sequence of statements " &
                           "executed");
         when Propagated_From_Task =>
            null;  -- This is the expected test path
         when others =>
            Report.Failed ("Wrong exception raised");
      end;

   exception
      when others =>
            Report.Failed ("Unexpected exception raised");
   end;

   Report.Result;

end C974009;