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-- C974011.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 not executed if the triggering
-- statement is a task entry call and the entry is not accepted
-- before the abortable part completes.
-- Check that the call queued on the entry is cancelled
--
-- TEST DESCRIPTION:
-- Declare a main procedure containing an asynchronous select with a task
-- entry call as triggering statement. Force the entry call to be
-- queued by having the task call a procedure, prior to the corresponding
-- accept statement, which simulates (with a delay) a routine waiting
-- for user input
--
-- Once the call is known to be queued, complete the abortable part.
-- Check that the rendezvous (and thus the trigger) does not complete.
-- Then clear the barrier and check that the entry has been cancelled
--
--
-- CHANGE HISTORY:
-- 06 Dec 94 SAIC ACVC 2.0
-- 28 Nov 95 SAIC Eliminated shared global variable for ACVC 2.0.1
--
--!
with ImpDef;
--
package C974011_0 is -- Automated teller machine abstraction.
type Key_Enum is (None, Cancel, Deposit, Withdraw);
protected Key_PO is
procedure Set (K : Key_Enum);
function Value return Key_Enum;
private
Current : Key_Enum := None;
end Key_PO;
-- Flags for testing purposes
TC_Abortable_Part_Completed : Boolean := False;
TC_Rendezvous_Entered : Boolean := False;
TC_Delay_Time : constant duration := ImpDef.Switch_To_New_Task;
Count : Integer := 1234; -- Global to defeat optimization.
type Card_Number_Type is private;
type Card_PIN_Type is private;
type ATM_Card_Type is private;
Transaction_Canceled : exception;
task type ATM_Keyboard_Task is
entry Cancel_Pressed;
end ATM_Keyboard_Task;
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 C974011_0;
--==================================================================--
with Report;
package body C974011_0 is
protected body Key_PO is
procedure Set (K : Key_Enum) is
begin
Current := K;
end Set;
function Value return Key_Enum is
begin
return Current;
end Value;
end Key_PO;
procedure Listen_For_Input (Key : out Key_Enum) is
begin
-- Model the situation where the user does not press cancel thus
-- allowing validation to complete
delay TC_Delay_Time; -- Long enough to force queuing on
-- Keyboard.Cancel_Pressed.
Key := Key_PO.Value;
end Listen_For_Input;
-- One of these gets created as "Keyboard" for each transaction
--
task body ATM_Keyboard_Task is
Key_Pressed : Key_Enum;
begin
loop
-- Force entry calls
Listen_For_Input (Key_Pressed); -- to be queued,
select
when (Key_Pressed = Cancel) =>
accept Cancel_Pressed do
TC_Rendezvous_Entered := True;
end Cancel_Pressed;
-- User has cancelled the transaction so we exit the
-- loop and allow the task to terminate
exit;
else
delay ImpDef.Switch_To_New_Task;
end select;
end loop;
exception
when others =>
Report.Failed ("Unexpected Exception in ATM_Keyboard_Task");
end ATM_Keyboard_Task;
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
Count := (Count + 1) mod Integer (Card.PIN);
-- Simulate a validation activity which is longer than the time
-- taken in Listen_For_Input but not inordinately so.
delay TC_Delay_Time * 2;
end Validate_Card;
procedure Perform_Transaction (Card : in ATM_Card_Type) is
begin
if TC_Rendezvous_Entered then
Report.Failed ("Triggering statement completed");
end if;
if Count = 1234 then
-- Initial value is unchanged
Report.Failed ("Abortable part did not execute");
end if;
if not TC_Abortable_Part_Completed then
Report.Failed ("Abortable part did not complete");
end if;
end Perform_Transaction;
end C974011_0;
--==================================================================--
with Report;
with C974011_0; -- Automated teller machine abstraction.
use C974011_0;
procedure C974011 is
Card_Data : ATM_Card_Type;
begin -- Main program.
Report.Test ("C974011", "Asynchronous Select: Trigger is queued on a " &
"task entry and the abortable part " &
"completes first");
Read_Card (Card_Data);
declare
-- Create the task for this transaction
Keyboard : C974011_0.ATM_Keyboard_Task;
begin
-- --
-- Asynchronous select is tested here --
-- --
select
Keyboard.Cancel_Pressed; -- Entry call is initially queued, so
-- abortable part starts.
raise Transaction_Canceled; -- This would be executed if we
-- completed the rendezvous
then abort
Validate_Card (Card_Data);
TC_Abortable_Part_Completed := true;
end select;
Perform_Transaction (Card_Data);
-- Now clear the entry barrier to allow the rendezvous to complete
-- if the triggering call has not been cancelled
Key_PO.Set (Cancel);
--
delay TC_Delay_Time; -- to allow it all to take place
if TC_Rendezvous_Entered then
Report.Failed ("Triggering Call was not cancelled");
end if;
abort Keyboard; -- clean up. (Note: the task will only exit the
-- loop and terminate if the call hanging on the
-- entry is executed.)
exception
when Transaction_Canceled =>
Report.Failed ("Triggering alternative sequence of statements " &
"executed");
when Others =>
Report.Failed ("Unexpected exception in the Main");
end;
Report.Result;
end C974011;
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