c974010.a

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-- C974010.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 to
--      a task that has already terminated.
--
--      Check that Tasking_Error 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 Tasking_Error 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.  Ensure that the task is
--      terminated before the entry call.  Use stripped down versions of
--      the  called procedures to check the correct path in the test.
--
--
-- CHANGE HISTORY:
--      06 Dec 94   SAIC    ACVC 2.0
--
--!

package C974010_0 is  -- Automated teller machine abstraction.


   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 C974010_0;


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


with Report;
package body C974010_0 is



   -- One of these gets created as "Keyboard" for each transaction
   --
   task body ATM_Keyboard_Task is
      TC_Suicide  : exception;
      Key_Pressed : Key_Enum := None;
   begin
      raise TC_Suicide;   -- Simulate early, unexpected termination

      accept Cancel_Pressed do        -- queued entry call.
         null;  --:::: user code for cancel
                 
      end Cancel_Pressed;

   exception
      when TC_Suicide =>
         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 C974010_0;


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


with Report;
with ImpDef;

with C974010_0;  -- Automated teller machine abstraction.
use  C974010_0;

procedure C974010 is

   Card_Data : ATM_Card_Type;
   TC_Tasking_Error_Handled : Boolean := false;

begin  -- Main program.

   Report.Test ("C974010", "Asynchronous Select: Trigger is a call to a " &
                           "task entry of a task that is already completed");


   declare
      -- Create the task for this transaction
      Keyboard : C974010_0.ATM_Keyboard_Task;
   begin

      -- Ensure the task is already completed before calling
      --
      while not Keyboard'terminated loop
         delay ImpDef.Minimum_Task_Switch;
      end loop;

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

      select
 
         Keyboard.Cancel_Pressed;

         raise Transaction_Canceled;  -- Should not be executed.

      then abort

         -- Since the triggering call is not queued the abortable part
         -- should not be executed.
         --
         Validate_Card (Card_Data);  

      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 Tasking_Error =>
         -- This is the expected test path
         TC_Tasking_Error_Handled := true;
      when others       =>
         Report.Failed ("Wrong exception raised: ");
   end;

   
   if not TC_Tasking_Error_Handled then
      Report.Failed ("Tasking_Error not properly propagated");
   end if;

   Report.Result;

exception
   when Tasking_Error =>
        Report.Failed ("Tasking_Error propagated to wrong handler");
        Report.Result;


end C974010;