Subversion Repositories openrisc_2011-10-31

-- C97201G.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  G:  THE CORRESPONDING ACCEPT_STATEMENT IS CLOSED

--     AND THIS FACT IS STATICALLY DETERMINABLE.

-- RM 4/21/82

WITH REPORT; USE REPORT;

PROCEDURE C97201G IS

     ELSE_BRANCH_TAKEN    :  BOOLEAN  :=  FALSE ;

     RENDEZVOUS_OCCURRED  :  BOOLEAN  :=  FALSE ;

     QUEUE_NOT_EMPTY      :  BOOLEAN  :=  FALSE ;

     X                    :  INTEGER  :=  17 ;

BEGIN

     TEST ("C97201G", "CHECK THAT NO RENDEZVOUS REQUESTED BY"      &

                      " A CONDITIONAL_ENTRY_CALL CAN EVER OCCUR"   &

                      " IF THE CORRESPONDING ACCEPT_STATEMENT IS"  &

                      " CLOSED"                                    );

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

     DECLARE

          TASK  T  IS

               ENTRY  DO_IT_NOW_ORELSE( DID_YOU_DO_IT : IN OUT BOOLEAN);

               ENTRY  KEEP_ALIVE ;

          END  T ;

          TASK BODY  T  IS

          BEGIN

               IF  DO_IT_NOW_ORELSE'COUNT /= 0  THEN

                    QUEUE_NOT_EMPTY := TRUE ;

               END IF;

               SELECT

                    WHEN  3 = 5  =>

                         ACCEPT  DO_IT_NOW_ORELSE

                                      ( DID_YOU_DO_IT : IN OUT BOOLEAN)

                         DO

                              DID_YOU_DO_IT := TRUE ;

                         END;

               OR

                         ACCEPT  KEEP_ALIVE ; -- TO PREVENT SELECT_ERROR

               END SELECT;

               IF  DO_IT_NOW_ORELSE'COUNT /= 0  THEN

                    QUEUE_NOT_EMPTY := TRUE ;

               END IF;

          END  T ;

     BEGIN

          COMMENT( "PERMANENTLY CLOSED" );

          SELECT

               T.DO_IT_NOW_ORELSE( RENDEZVOUS_OCCURRED );

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

                            --      THEREFORE THIS BRANCH MUST BE CHOSEN

               ELSE_BRANCH_TAKEN := TRUE ;

               COMMENT( "ELSE_BRANCH  TAKEN" );

          END SELECT;

          T.KEEP_ALIVE ;    -- THIS ALSO UPDATES THE NONLOCALS

     END;   -- END OF BLOCK CONTAINING THE ENTRY CALL

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

     -- BY NOW, THE TASK IS TERMINATED

     IF  RENDEZVOUS_OCCURRED

     THEN

          FAILED( "RENDEZVOUS OCCURRED" );

     END IF;

     IF  QUEUE_NOT_EMPTY

     THEN

          FAILED( "ENTRY QUEUE NOT EMPTY" );

     END IF;

     IF  ELSE_BRANCH_TAKEN  THEN

          NULL ;

     ELSE

          FAILED( "RENDEZVOUS ATTEMPTED?" );

     END IF;

     RESULT;

END  C97201G ;