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-- C97201A.ADA

--                             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.

--*

-- CHECK THAT A RENDEZVOUS REQUESTED BY A CONDITIONAL_ENTRY_CALL

--     IS PERFORMED ONLY IF IMMEDIATELY POSSIBLE.

-- CASE  A:  THE TASK TO BE CALLED IS NOT YET ACTIVE AS OF THE

--     MOMENT OF CALL (CONDITIONAL_ENTRY_CALL),

--     AND THIS FACT CAN BE DETERMINED STATICALLY.

-- RM 4/20/82

WITH REPORT; USE REPORT;

PROCEDURE C97201A IS

     ELSE_BRANCH_TAKEN    :  INTEGER  :=  3 ;

BEGIN

     TEST ("C97201A", "CHECK THAT NO RENDEZVOUS REQUESTED BY"      &

                      " A CONDITIONAL_ENTRY_CALL CAN OCCUR  WHILE" &

                      " THE CALLED TASK IS NOT YET ACTIVE"         );

     -------------------------------------------------------------------

     DECLARE

          TASK  T  IS

               ENTRY  DO_IT_NOW_ORELSE ( AUTHORIZED : IN BOOLEAN ) ;

          END  T ;

          TASK BODY  T  IS

               PACKAGE       SECOND_ATTEMPT  IS    END  SECOND_ATTEMPT ;

               PACKAGE BODY  SECOND_ATTEMPT  IS

               BEGIN

                    SELECT

                         DO_IT_NOW_ORELSE (FALSE) ;--CALLING (OWN) ENTRY

                    ELSE    -- (I.E. CALLER ADOPTS A NO-WAIT POLICY)

                            --      THEREFORE THIS BRANCH MUST BE CHOSEN

                         ELSE_BRANCH_TAKEN := 2 * ELSE_BRANCH_TAKEN ;

                         COMMENT( "ELSE_BRANCH  TAKEN  (#2)" );

                    END SELECT;

               END  SECOND_ATTEMPT ;

          BEGIN

               ACCEPT DO_IT_NOW_ORELSE ( AUTHORIZED : IN BOOLEAN )  DO

                    IF  AUTHORIZED  THEN

                         COMMENT(  "AUTHORIZED ENTRY_CALL" );

                    ELSE

                         FAILED( "UNAUTHORIZED ENTRY_CALL" );

                    END IF;

               END DO_IT_NOW_ORELSE ;

          END  T ;

          PACKAGE       FIRST_ATTEMPT  IS      END  FIRST_ATTEMPT ;

          PACKAGE BODY  FIRST_ATTEMPT  IS

          BEGIN

               SELECT

                    T.DO_IT_NOW_ORELSE (FALSE) ;

               ELSE        -- (I.E. CALLER ADOPTS A NO-WAIT POLICY)

                            --      THEREFORE THIS BRANCH MUST BE CHOSEN

                    ELSE_BRANCH_TAKEN := 1 + ELSE_BRANCH_TAKEN ;

                    COMMENT( "ELSE_BRANCH  TAKEN  (#1)" );

               END SELECT;

          END  FIRST_ATTEMPT ;

     BEGIN

          T.DO_IT_NOW_ORELSE ( TRUE );   -- TO SATISFY THE SERVER'S

                                          --     WAIT FOR SUCH A CALL

     EXCEPTION

          WHEN  TASKING_ERROR  =>

               FAILED( "TASKING ERROR" );

     END  ;

     -------------------------------------------------------------------

     -- BY NOW, THE TASK IS TERMINATED  (AND THE NONLOCALS UPDATED)

     CASE  ELSE_BRANCH_TAKEN  IS

          WHEN  3  =>

               FAILED( "NO 'ELSE'; BOTH (?) RENDEZVOUS ATTEMPTED?" );

          WHEN  4  =>

               FAILED( "'ELSE' #1 ONLY; RENDEZVOUS (#2) ATTEMPTED?" );

          WHEN  6  =>

               FAILED( "'ELSE' #2 ONLY; RENDEZVOUS (#1) ATTEMPTED?" );

          WHEN  7  =>

               FAILED( "WRONG ORDER FOR 'ELSE':  #2,#1 " );

          WHEN  8  =>

               NULL ;

          WHEN  OTHERS  =>

               FAILED( "WRONG CASE_VALUE" );

     END CASE;

     RESULT;

END  C97201A ;