c974006.a

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-- C974006.A
--
--                             Grant of Unlimited Rights
--
--     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 sequence of statements of the triggering alternative
--      of an asynchronous select statement is executed if the triggering
--      statement is a protected entry call, and the entry is accepted
--      immediately. Check that the corresponding entry body is executed
--      before the sequence of statements of the triggering alternative.
--      Check that the abortable part is not executed.
--
-- TEST DESCRIPTION:
--      Declare a main procedure containing an asynchronous select with a
--      protected entry call as triggering statement. Declare a protected
--      procedure which sets the protected entry's barrier true. Force the
--      entry call to be accepted immediately by calling this protected
--      procedure prior to the asynchronous select. Since the entry call
--      is accepted immediately, the abortable part should never start. When
--      entry call completes, the sequence of statements of the triggering
--      alternative should execute.
--
--
-- CHANGE HISTORY:
--      06 Dec 94   SAIC    ACVC 2.0
--
--!


package C974006_0 is  -- Automated teller machine abstraction.


   -- Flag for testing purposes:

   Entry_Body_Executed : Boolean := False;


   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;


   Transaction_Canceled : exception;


   protected type ATM_Keyboard_Protected is
      entry Cancel_Pressed;
      procedure Read_Key;
   private
      Last_Key_Pressed : Key_Enum := None;
   end ATM_Keyboard_Protected;


   procedure Read_Card (Card : in out ATM_Card_Type);

   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 C974006_0;


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


with Report;
package body C974006_0 is


   protected body ATM_Keyboard_Protected is

      entry Cancel_Pressed when (Last_Key_Pressed = Cancel) is
      begin
         Entry_Body_Executed := True;
      end Cancel_Pressed;

      procedure Read_Key is
      begin
         -- Simulate a procedure which processes user keyboard input, and
         -- which is called by some interrupt handler.
         Last_Key_Pressed := Cancel;
      end Read_Key;

   end ATM_Keyboard_Protected;


   procedure Read_Card (Card : in out ATM_Card_Type) is
   begin
      Card.Number := 9999;
      Card.PIN    := 111;
   end Read_Card;


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


   procedure Perform_Transaction (Card : in ATM_Card_Type) is
   begin
      Report.Failed ("Triggering alternative sequence of statements " &
                      "not fully executed");
   end Perform_Transaction;


end C974006_0;


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


with Report;

with C974006_0;  -- Automated teller machine abstraction.
use  C974006_0;

procedure C974006 is

   Card_Data : ATM_Card_Type;

begin

   Report.Test ("C974006", "ATC: trigger is protected entry call" &
                              " and completes first");

   Read_Card (Card_Data);

   declare
      Keyboard : C974006_0.ATM_Keyboard_Protected;
   begin

      -- Simulate the situation where the user hits cancel before the
      -- validation process can start:
      Keyboard.Read_Key;                 -- Force Keyboard.Cancel_Pressed to
                                         -- be accepted immediately.

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

      select
         Keyboard.Cancel_Pressed;        -- Entry call is accepted immediately,
                                         -- so abortable part does NOT start.

         if not Entry_Body_Executed then -- Executes after entry completes.
            Report.Failed ("Triggering alternative sequence of statements " &
                           "executed before triggering statement complete");
         end if;

         raise Transaction_Canceled;     -- Control passes to exception
                                         -- handler.
      then abort
         Validate_Card (Card_Data);      -- Should not be executed.
      end select;
      Perform_Transaction (Card_Data);   -- Should not be reached.
   exception
      when Transaction_Canceled =>
         null;
   end;

   Report.Result;

end C974006;