| -- C954023.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 within a protected entry to a family of entries |
| -- in a different protected object is queued correctly |
| -- Call with parameters |
| -- Requeue with abort |
| -- |
| -- TEST DESCRIPTION: |
| -- One transaction is sent through to check the paths. After processing |
| -- this, the Credit task sets the "overloaded" indicator. Once this |
| -- indicator is set the Distributor (a protected object) queues lower |
| -- priority transactions on a family of queues (Wait_for_Underload) in |
| -- another protected object using a requeue. The Distributor still |
| -- delivers high priority transactions. After two more high priority |
| -- transactions have been processed by the Credit task the artificial |
| -- test code clears the overload condition to the threshold level that |
| -- allows only the items on the Medium priority queue of the family to be |
| -- released. When these have been processed and checked the test code |
| -- then lowers the priority threshold once again, allowing the Low |
| -- priority items from the last queue in the family to be released, |
| -- processed and checked. Note: the High priority queue in the family is |
| -- not used. |
| -- |
| -- 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 |
| -- |
| --! |
| |
| with Report; |
| with ImpDef; |
| |
| procedure C954023 is |
| |
| -- Artificial: number of messages required for this test |
| subtype TC_Trans_Range is integer range 1..8; |
| |
| TC_Credit_Messages_Expected : constant integer |
| := TC_Trans_Range'Last - 1; |
| |
| TC_Debit_Message_Complete : Boolean := false; |
| |
| |
| -- Mechanism for handshaking between tasks |
| protected TC_PO is |
| procedure Increment_Tasks_Completed_Count; |
| function Tasks_Completed_Count return integer; |
| function First_Message_Has_Arrived return Boolean; |
| procedure Set_First_Message_Has_Arrived; |
| private |
| Number_Complete : integer := 0; |
| Message_Arrived_Flag : Boolean := false; |
| end TC_PO; |
| -- |
| protected body TC_PO is |
| procedure Increment_Tasks_Completed_Count is |
| begin |
| Number_Complete := Number_Complete + 1; |
| end Increment_Tasks_Completed_Count; |
| |
| function Tasks_Completed_Count return integer is |
| begin |
| return Number_Complete; |
| end Tasks_Completed_Count; |
| |
| function First_Message_Has_Arrived return Boolean is |
| begin |
| return Message_Arrived_Flag; |
| end First_Message_Has_Arrived; |
| |
| procedure Set_First_Message_Has_Arrived is |
| begin |
| Message_Arrived_Flag := true; |
| end Set_First_Message_Has_Arrived; |
| |
| end TC_PO; |
| |
| begin |
| |
| Report.Test ("C954023", "Requeue from within a protected object" & |
| " to a family of entries in another protected object"); |
| |
| |
| declare -- encapsulate the test |
| |
| -- Arbitrary test values |
| Credit_Return : constant := 1; |
| Debit_Return : constant := 2; |
| |
| type Transaction_Code is (Credit, Debit); |
| type App_Priority is (Low, Medium, High); |
| type Priority_Block is array (App_Priority) of Boolean; |
| |
| type Transaction_Record; |
| type acc_Transaction_Record is access Transaction_Record; |
| type Transaction_Record is |
| record |
| ID : integer := 0; |
| Code : Transaction_Code := Debit; |
| Priority : App_Priority := High; |
| Account_Number : integer := 0; |
| Stock_Number : integer := 0; |
| Quantity : integer := 0; |
| Return_Value : integer := 0; |
| TC_Message_Count : integer := 0; |
| TC_Thru_Distrib : Boolean := false; |
| 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; |
| |
| protected Distributor is |
| procedure Set_Credit_Overloaded; |
| procedure Clear_Overload_to_Medium; |
| procedure Clear_Overload_to_Low; |
| entry Input (Transaction : acc_Transaction_Record); |
| private |
| Credit_Overloaded : Boolean := false; |
| end Distributor; |
| |
| protected Hold is |
| procedure Release_Medium; |
| procedure Release_Low; |
| -- Family of entry queues indexed by App_Priority |
| entry Wait_for_Underload (App_Priority) |
| (Transaction : acc_Transaction_Record); |
| private |
| Release : Priority_Block := (others => false); |
| end Hold; |
| |
| 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; |
| |
| -- |
| -- Dispose each input Transaction_Record to the appropriate |
| -- computation tasks |
| -- |
| protected body Distributor is |
| |
| procedure Set_Credit_Overloaded is |
| begin |
| Credit_Overloaded := true; |
| end Set_Credit_Overloaded; |
| |
| procedure Clear_Overload_to_Medium is |
| begin |
| Credit_Overloaded := false; |
| Hold.Release_Medium; -- Release all held messages on Medium |
| -- priority queue |
| end Clear_Overload_to_Medium; |
| |
| procedure Clear_Overload_to_Low is |
| begin |
| Credit_Overloaded := false; |
| Hold.Release_Low; -- Release all held messages on Low |
| -- priority queue |
| end Clear_Overload_to_Low; |
| |
| |
| |
| entry Input (Transaction : acc_Transaction_Record) when true is |
| -- barrier is always open |
| begin |
| -- Test Control: Set the indicator in the message to show it has |
| -- passed through the Distributor object |
| Transaction.TC_thru_Distrib := true; |
| |
| -- Pass this transaction on to the appropriate computation |
| -- task but temporarily hold low-priority transactions under |
| -- overload conditions |
| case Transaction.Code is |
| when Credit => |
| if Credit_Overloaded and Transaction.Priority /= High then |
| -- use the appropriate queue in the family |
| requeue Hold.Wait_for_Underload(Transaction.Priority) |
| with abort; |
| else |
| requeue Credit_Computation.Input with abort; |
| end if; |
| when Debit => |
| requeue Debit_Computation.Input with abort; |
| end case; |
| end Input; |
| end Distributor; |
| |
| |
| -- Low priority Message tasks are held on the Wait_for_Underload queue |
| -- while the Credit computation system is overloaded. Once the Credit |
| -- system reached underload send all queued messages immediately |
| -- |
| protected body Hold is |
| |
| -- Once these are executed the barrier conditions for the entries |
| -- are evaluated |
| procedure Release_Medium is |
| begin |
| Release(Medium) := true; |
| end Release_Medium; |
| -- |
| procedure Release_Low is |
| begin |
| Release(Low) := true; |
| end Release_Low; |
| |
| -- This is a family of entry queues indexed by App_Priority |
| entry Wait_for_Underload (for AP in App_Priority) |
| (Transaction : acc_Transaction_Record) |
| when Release(AP) is |
| begin |
| requeue Credit_Computation.Input with abort; |
| if Wait_for_Underload(AP)'count = 0 then |
| -- Queue is purged. Set up to hold next batch |
| Release(AP) := false; |
| end if; |
| end Wait_for_Underload; |
| |
| end Hold; |
| |
| |
| |
| |
| -- 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. |
| -- The Line Driver task would normally be designed to loop |
| -- creating the messages as input is received. Simulate this |
| -- but limit it to the required number of dummy messages needed for |
| -- this test and allow it to terminate at that point. Artificially |
| -- cycle the generation of High medium and Low priority Credit |
| -- transactions for this test. Send out one final Debit message |
| -- |
| task body Line_Driver is |
| Current_ID : integer := 1; |
| Current_Priority : App_Priority := High; |
| |
| 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.Priority := Current_Priority; |
| |
| 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 |
| |
| for Transaction_Numb in TC_Trans_Range loop -- TC: limit the loop |
| 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 Transaction_Numb = TC_Trans_Range'first then |
| -- Send the first Credit message |
| Build_Credit_Record ( Next_Transaction ); |
| Next_Message_Task.Accept_Transaction ( Next_Transaction ); |
| -- TC: Wait until the first message has been received by the |
| -- Credit task and it has set the Overload indicator for the |
| -- Distributor |
| while not TC_PO.First_Message_Has_Arrived loop |
| delay ImpDef.Minimum_Task_Switch; |
| end loop; |
| elsif Transaction_Numb = TC_Trans_Range'last then |
| -- For this test send the last transaction to the Debit task |
| -- to improve the mix |
| Build_Debit_Record( Next_Transaction ); |
| Next_Message_Task.Accept_Transaction ( Next_Transaction ); |
| else |
| -- TC: Cycle generation of high medium and low priority |
| -- transactions |
| if Current_Priority = High then |
| Current_Priority := Medium; |
| elsif |
| Current_Priority = Medium then |
| Current_Priority := Low; |
| else |
| Current_Priority := High; |
| end if; |
| Build_Credit_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 |
| if This_Transaction.Return_Value /= Credit_Return or |
| not This_Transaction.TC_thru_Distrib then |
| Report.Failed ("Expected path not traversed - Credit"); |
| end if; |
| TC_PO.Increment_Tasks_Completed_Count; |
| 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 - Debit"); |
| end if; |
| TC_Debit_Message_Complete := true; |
| end if; |
| |
| exception |
| when others => |
| Report.Failed ("Unexpected exception in Message_Task"); |
| end Message_Task; |
| |
| |
| |
| |
| |
| -- Computation task. After the computation is performed 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 following is all Test Control code: |
| |
| 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; |
| |
| -- This is checked by the Message_Task: |
| Transaction.Return_Value := Credit_Return; |
| |
| -- Now take special action depending on which Message. |
| -- Note: The count gives the order in which the messages are |
| -- arriving at this task NOT the order in which they |
| -- were originally generated and sent out. |
| |
| Message_Count := Message_Count + 1; |
| |
| if Message_Count < 4 then |
| -- This is one of the first three messages which must |
| -- be High priority because we will set "Overload" after |
| -- the first, which is known to be High. The lower |
| -- priority should be waiting on the queues |
| if Transaction.Priority /= High then |
| Report.Failed |
| ("Credit Task: Lower priority trans. during overload"); |
| end if; |
| if Message_Count = 1 then |
| -- After the first message : |
| Distributor.Set_Credit_Overloaded; |
| -- Now flag the Line_Driver that the second and |
| -- subsequent messages may now be sent |
| TC_PO.Set_First_Message_Has_Arrived; |
| elsif |
| Message_Count = 3 then |
| -- The two high priority transactions created |
| -- subsequent to the overload have now been processed, |
| -- release the Medium priority items |
| Distributor.Clear_Overload_to_Medium; |
| end if; |
| elsif Message_Count < 6 then |
| -- This must be one of the Medium priority messages |
| if Transaction.Priority /= Medium then |
| Report.Failed |
| ("Credit Task: Second group not Medium Priority"); |
| end if; |
| if Message_Count = 5 then |
| -- The two medium priority transactions |
| -- have now been processed - release the |
| -- Low priority items |
| Distributor.Clear_Overload_to_Low; |
| end if; |
| elsif Message_Count < TC_Trans_Range'Last then |
| -- This must be one of the Low priority messages |
| if Transaction.Priority /= Low then |
| Report.Failed |
| ("Credit Task: Third group not Low Priority"); |
| end if; |
| else |
| -- Too many transactions have arrived. Duplicates? |
| -- the Debit transaction? |
| Report.Failed |
| ("Credit Task: Too many transactions"); |
| end if; |
| end Input; |
| or |
| terminate; |
| end select; |
| end loop; |
| exception |
| when others => |
| Report.Failed ("Unexpected exception in Credit_Computation"); |
| end Credit_Computation; |
| |
| |
| |
| -- Computation task. After the computation is performed 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 |
| |
| -- For the test: |
| 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 -- declare |
| |
| null; |
| |
| end; -- declare (test encapsulation) |
| |
| if (TC_PO.Tasks_Completed_Count /= TC_Credit_Messages_Expected) |
| and not TC_Debit_Message_Complete then |
| Report.Failed ("Incorrect number of Message Tasks completed"); |
| end if; |
| |
| Report.Result; |
| |
| end C954023; |
