| -- C954014.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 a requeue is not canceled and that the requeueing |
| -- task is unaffected when a calling task is aborted. Check that the |
| -- abort is deferred until the entry call is complete. |
| -- Specifically, check requeue to an entry in a different task, |
| -- requeue where the entry call has parameters, and requeue |
| -- without the abort option. |
| -- |
| -- TEST DESCRIPTION |
| -- In the Driver create a task that places a call on the |
| -- Distributor. In the Distributor requeue this call on the Credit task. |
| -- Abort the calling task when it is known to be in rendezvous with the |
| -- Credit task. (We arrange this by using artificial synchronization |
| -- points in the Driver and the accept body of the Credit task) Ensure |
| -- that the abort is deferred (the task is not terminated) until the |
| -- accept body completes. Afterwards, send one extra message through |
| -- the Distributor to check that the requeueing task has not been |
| -- disrupted. |
| -- |
| -- This series of tests uses a simulation of a transaction driven |
| -- processing system. Line Drivers accept input from an external source |
| -- and build them into transaction records. These records are then |
| -- encapsulated in message tasks which remain extant for the life of the |
| -- transaction in the system. The message tasks put themselves on the |
| -- input queue of a Distributor which, from information in the |
| -- transaction and/or system load conditions forwards them to other |
| -- operating tasks. These in turn might forward the transactions to yet |
| -- other tasks for further action. The routing is, in real life, dynamic |
| -- and unpredictable at the time of message generation. All rerouting in |
| -- this model is done by means of requeues. |
| -- |
| -- |
| -- CHANGE HISTORY: |
| -- 06 Dec 94 SAIC ACVC 2.0 |
| -- 25 Nov 95 SAIC Replaced global variables with protected objects |
| -- for ACVC 2.0.1. |
| -- |
| --! |
| |
| with Report; |
| with ImpDef; |
| |
| procedure C954014 is |
| |
| -- Arbitrary test values |
| Credit_Return : constant := 1; |
| Debit_Return : constant := 2; |
| |
| |
| protected type Shared_Boolean (Initial_Value : Boolean := False) is |
| procedure Set_True; |
| procedure Set_False; |
| function Value return Boolean; |
| private |
| Current_Value : Boolean := Initial_Value; |
| end Shared_Boolean; |
| |
| protected body Shared_Boolean is |
| procedure Set_True is |
| begin |
| Current_Value := True; |
| end Set_True; |
| |
| procedure Set_False is |
| begin |
| Current_Value := False; |
| end Set_False; |
| |
| function Value return Boolean is |
| begin |
| return Current_Value; |
| end Value; |
| end Shared_Boolean; |
| |
| |
| TC_Debit_Message_Complete : Shared_Boolean (False); |
| |
| -- Synchronization flags for handshaking between the Line_Driver |
| -- and the Accept body in the Credit Task |
| TC_Handshake_A : Shared_Boolean (False); |
| TC_Handshake_B : Shared_Boolean (False); |
| TC_Handshake_C : Shared_Boolean (False); |
| TC_Handshake_D : Shared_Boolean (False); |
| TC_Handshake_E : Shared_Boolean (False); |
| TC_Handshake_F : Shared_Boolean (False); |
| |
| |
| type Transaction_Code is (Credit, Debit); |
| |
| type Transaction_Record; |
| type acc_Transaction_Record is access Transaction_Record; |
| type Transaction_Record is |
| record |
| ID : integer := 0; |
| Code : Transaction_Code := Debit; |
| Account_Number : integer := 0; |
| Stock_Number : integer := 0; |
| Quantity : integer := 0; |
| Return_Value : integer := 0; |
| TC_Message_Count : integer := 0; |
| TC_Thru_Distrib : Boolean; |
| end record; |
| |
| |
| task type Message_Task is |
| entry Accept_Transaction (In_Transaction : acc_Transaction_Record); |
| end Message_Task; |
| type acc_Message_Task is access Message_Task; |
| |
| task Line_Driver is |
| entry start; |
| end Line_Driver; |
| |
| task Distributor is |
| entry Input(Transaction : acc_Transaction_Record); |
| end Distributor; |
| |
| task Credit_Computation is |
| entry Input(Transaction : acc_Transaction_Record); |
| end Credit_Computation; |
| |
| task Debit_Computation is |
| entry Input(Transaction : acc_Transaction_Record); |
| end Debit_Computation; |
| |
| |
| -- Assemble messages received from an external source |
| -- Creates a message task for each. The message tasks remain extant |
| -- for the life of the messages in the system. |
| -- TC: The Line Driver task would normally be designed to loop |
| -- continuously creating the messages as input is received. Simulate |
| -- this but limit it to two dummy messages for this test and use |
| -- special artificial handshaking checks with the Credit accept body |
| -- to control the test. Allow it to terminate at the end |
| -- |
| task body Line_Driver is |
| Current_ID : integer := 1; |
| TC_First_message_sent: Boolean := false; |
| |
| procedure Build_Credit_Record |
| ( Next_Transaction : acc_Transaction_Record ) is |
| Dummy_Account : constant integer := 100; |
| begin |
| Next_Transaction.ID := Current_ID; |
| Next_Transaction.Code := Credit; |
| |
| Next_Transaction.Account_Number := Dummy_Account; |
| Current_ID := Current_ID + 1; |
| end Build_Credit_Record; |
| |
| |
| procedure Build_Debit_Record |
| ( Next_Transaction : acc_Transaction_Record ) is |
| Dummy_Account : constant integer := 200; |
| begin |
| Next_Transaction.ID := Current_ID; |
| Next_Transaction.Code := Debit; |
| |
| Next_Transaction.Account_Number := Dummy_Account; |
| Current_ID := Current_ID + 1; |
| end Build_Debit_Record; |
| |
| begin |
| |
| accept Start; -- Wait for trigger from main |
| |
| for i in 1..2 loop -- TC: arbitrarily limit to one credit message |
| -- and one debit, then complete |
| declare |
| -- Create a task for the next message |
| Next_Message_Task : acc_Message_Task := new Message_Task; |
| -- Create a record for it |
| Next_Transaction : acc_Transaction_Record := |
| new Transaction_Record; |
| begin |
| if not TC_First_Message_Sent then |
| -- send out the first message which will be aborted |
| Build_Credit_Record ( Next_Transaction ); |
| Next_Message_Task.Accept_Transaction ( Next_Transaction ); |
| TC_First_Message_Sent := true; |
| |
| -- Wait for Credit task to get into the accept body |
| -- The call from the Message Task has been requeued by |
| -- the distributor |
| while not TC_Handshake_A.Value loop |
| delay ImpDef.Minimum_Task_Switch; |
| end loop; |
| |
| -- Abort the calling task; the Credit task is guaranteed to |
| -- be in the accept body |
| abort Next_Message_Task.all; -- We are still in this declare |
| -- block |
| |
| -- Inform the Credit task that the abort has been initiated |
| TC_Handshake_B.Set_True; |
| |
| -- Now wait for the "acknowledgment" from the Credit task |
| -- this ensures a complete task switch (at least) |
| while not TC_Handshake_C.Value loop |
| delay ImpDef.Minimum_Task_Switch; |
| end loop; |
| |
| -- The aborted task must not terminate till the accept body |
| -- has completed |
| if Next_Message_Task'terminated then |
| Report.Failed ("The abort was not deferred"); |
| end if; |
| |
| -- Inform the Credit task that the termination has been checked |
| TC_Handshake_D.Set_True; |
| |
| -- Now wait for the completion of the accept body in the |
| -- Credit task |
| while not TC_Handshake_E.Value loop |
| delay ImpDef.Minimum_Task_Switch; |
| end loop; |
| |
| while not ( Next_Message_Task'terminated ) loop |
| delay ImpDef.Minimum_Task_Switch; |
| end loop; |
| |
| -- Indicate to the Main program that this section is complete |
| TC_Handshake_F.Set_True; |
| |
| else |
| -- The main part of the test is complete. Send one Debit message |
| -- as further exercise of the Distributor to ensure it has not |
| -- been affected by the abort of the requeue; |
| Build_Debit_Record ( Next_Transaction ); |
| Next_Message_Task.Accept_Transaction ( Next_Transaction ); |
| end if; |
| end; -- declare |
| end loop; |
| |
| exception |
| when others => |
| Report.Failed ("Unexpected exception in Line_Driver"); |
| end Line_Driver; |
| |
| |
| |
| task body Message_Task is |
| |
| TC_Original_Transaction_Code : Transaction_Code; |
| This_Transaction : acc_Transaction_Record := new Transaction_Record; |
| |
| begin |
| |
| accept Accept_Transaction (In_Transaction : acc_Transaction_Record) do |
| This_Transaction.all := In_Transaction.all; |
| end Accept_Transaction; |
| |
| -- Note the original code to ensure correct return |
| TC_Original_Transaction_Code := This_Transaction.Code; |
| |
| -- Queue up on Distributor's Input queue |
| Distributor.Input ( This_Transaction ); |
| -- This task will now wait for the requeued rendezvous |
| -- to complete before proceeding |
| |
| -- After the required computations have been performed |
| -- return the Transaction_Record appropriately (probably to an output |
| -- line driver) |
| null; -- stub |
| |
| -- For the test check that the return values are as expected |
| if TC_Original_Transaction_Code /= This_Transaction.Code then |
| -- Incorrect rendezvous |
| Report.Failed ("Message Task: Incorrect code returned"); |
| end if; |
| |
| if This_Transaction.Code = Credit then |
| -- The only Credit message was the one that should have been aborted |
| Report.Failed ("Abort was not effective"); |
| else |
| if This_Transaction.Return_Value /= Debit_Return or |
| This_Transaction.TC_Message_Count /= 1 or not |
| This_Transaction.TC_Thru_Distrib then |
| Report.Failed ("Expected path not traversed"); |
| end if; |
| TC_Debit_Message_Complete.Set_True; |
| end if; |
| |
| exception |
| when others => |
| Report.Failed ("Unexpected exception in Message_Task"); |
| |
| end Message_Task; |
| |
| |
| |
| -- Dispose each input Transaction_Record to the appropriate |
| -- computation tasks |
| -- |
| task body Distributor is |
| |
| begin |
| loop |
| select |
| accept Input (Transaction : acc_Transaction_Record) do |
| |
| -- Indicate that the message did pass through the |
| -- Distributor Task |
| Transaction.TC_Thru_Distrib := true; |
| |
| -- Pass this transaction on the appropriate computation |
| -- task |
| case Transaction.Code is |
| when Credit => |
| requeue Credit_Computation.Input; -- without abort |
| when Debit => |
| requeue Debit_Computation.Input; -- without abort |
| end case; |
| end Input; |
| or |
| terminate; |
| end select; |
| end loop; |
| |
| exception |
| when others => |
| Report.Failed ("Unexpected exception in Distributor"); |
| end Distributor; |
| |
| |
| |
| -- Computation task. |
| -- Note: After the computation is performed in this task and the |
| -- accept body is completed the rendezvous in the original |
| -- message task is completed. |
| task body Credit_Computation is |
| Message_Count : integer := 0; |
| begin |
| loop |
| select |
| accept Input ( Transaction : acc_Transaction_Record) do |
| -- Perform the computations required for this transaction |
| -- |
| null; -- stub |
| |
| -- The rest of this code is for Test Control |
| -- |
| if not Transaction.TC_Thru_Distrib then |
| Report.Failed |
| ("Credit Task: Wrong queue, Distributor bypassed"); |
| end if; |
| if Transaction.code /= Credit then |
| Report.Failed |
| ("Credit Task: Requeue delivered to the wrong queue"); |
| end if; |
| |
| -- for the test plug a known value and count |
| Transaction.Return_Value := Credit_Return; |
| -- one, and only one message should pass through |
| if Message_Count /= 0 then |
| Report.Failed ("Aborted Requeue was not canceled -1"); |
| end if; |
| Message_Count := Message_Count + 1; |
| Transaction.TC_Message_Count := Message_Count; |
| |
| -- Having done the basic housekeeping we now need to signal |
| -- that we are in the accept body of the credit task. The |
| -- message has arrived and the Line Driver may now abort the |
| -- calling task |
| TC_Handshake_A.Set_True; |
| |
| -- Now wait for the Line Driver to inform us the calling |
| -- task has been aborted |
| while not TC_Handshake_B.Value loop |
| delay ImpDef.Minimum_Task_Switch; |
| end loop; |
| |
| -- The abort has taken place |
| -- Inform the Line Driver that we are still running in the |
| -- accept body |
| TC_Handshake_C.Set_True; |
| |
| -- Now wait for the Line Driver to digest this information |
| while not TC_Handshake_D.Value loop |
| delay ImpDef.Minimum_Task_Switch; |
| end loop; |
| |
| -- The Line driver has checked that the caller is not terminated |
| -- We can now complete the accept |
| |
| end Input; |
| -- We are out of the accept |
| TC_Handshake_E.Set_True; |
| |
| or |
| terminate; |
| end select; |
| end loop; |
| exception |
| when others => |
| Report.Failed ("Unexpected exception in Credit_Computation"); |
| end Credit_Computation; |
| |
| |
| |
| -- Computation task. |
| -- Note: After the computation is performed in this task and the |
| -- accept body is completed the rendezvous in the original |
| -- message task is completed. |
| task body Debit_Computation is |
| Message_Count : integer := 0; |
| begin |
| loop |
| select |
| accept Input (Transaction : acc_Transaction_Record) do |
| -- Perform the computations required for this message |
| -- |
| null; -- stub |
| |
| -- The rest of this code is for Test Control |
| -- |
| if not Transaction.TC_Thru_Distrib then |
| Report.Failed |
| ("Debit Task: Wrong queue, Distributor bypassed"); |
| end if; |
| if Transaction.code /= Debit then |
| Report.Failed |
| ("Debit Task: Requeue delivered to the wrong queue"); |
| end if; |
| |
| -- for the test plug a known value and count |
| Transaction.Return_Value := Debit_Return; |
| -- one, and only one, message should pass through |
| Message_Count := Message_Count + 1; |
| Transaction.TC_Message_Count := Message_Count; |
| end Input; |
| or |
| terminate; |
| end select; |
| end loop; |
| exception |
| when others => |
| Report.Failed ("Unexpected exception in Debit_Computation"); |
| |
| |
| end Debit_Computation; |
| |
| |
| begin -- c954014 |
| Report.Test ("C954014", "Abort a task that has a call" & |
| " requeued_without_abort"); |
| |
| Line_Driver.Start; -- Start the test |
| |
| -- Wait for the message tasks to complete before reporting the result |
| -- |
| while not (TC_Handshake_F.Value -- abort not effective? |
| and TC_Debit_Message_Complete.Value -- Distributor affected? |
| and TC_Handshake_E.Value ) loop -- accept not completed? |
| delay ImpDef.Minimum_Task_Switch; |
| end loop; |
| |
| Report.Result; |
| |
| end C954014; |
