rulebld.c

NASA 开发使用的一个专家系统

   /*******************************************************/
   /*      "C" Language Integrated Production System      */
   /*                                                     */
   /*             CLIPS Version 6.05  04/09/97            */
   /*                                                     */
   /*                  RULE BUILD MODULE                  */
   /*******************************************************/

/*************************************************************/
/* Purpose: Provides routines to ntegrates a set of pattern  */
/*   and join tests associated with a rule into the pattern  */
/*   and join networks. The joins are integrated into the    */
/*   join network by routines in this module. The pattern    */
/*   is integrated by calling the external routine           */
/*   associated with the pattern parser that originally      */
/*   parsed the pattern.                                     */
/*                                                           */
/* Principal Programmer(s):                                  */
/*      Gary D. Riley                                        */
/*                                                           */
/* Contributing Programmer(s):                               */
/*                                                           */
/* Revision History:                                         */
/*                                                           */
/*************************************************************/

#define _RULEBLD_SOURCE_

#include "setup.h"

#if DEFRULE_CONSTRUCT && (! RUN_TIME) && (! BLOAD_ONLY)

#include <stdio.h>
#define _CLIPS_STDIO_

#include "constant.h"
#include "clipsmem.h"
#include "router.h"
#include "watch.h"
#include "constrct.h"
#include "drive.h"
#include "pattern.h"
#include "reteutil.h"
#include "incrrset.h"
#include "rulebld.h"

/***************************************/
/* LOCAL INTERNAL FUNCTION DEFINITIONS */
/***************************************/

#if ANSI_COMPILER
   static struct joinNode        *FindShareableJoin(struct joinNode *,VOID *,int,int,int,
                                                    struct expr *,
                                                    int,int,int,struct joinNode **);
   static int                     TestJoinForReuse(struct joinNode *,int,int,int,
                                                   struct expr *,
                                                   int,int,int,struct joinNode **);
   static struct joinNode        *CreateNewJoin(struct expr *,
                                                struct joinNode *,VOID *,int,int);
   static VOID                    AttachTestCEsToPatternCEs(struct lhsParseNode *);                                           
#else
   static struct joinNode        *FindShareableJoin();
   static int                     TestJoinForReuse();
   static struct joinNode        *CreateNewJoin();
   static VOID                    AttachTestCEsToPatternCEs(); 
#endif
  
/****************************************************************/
/* ConstructJoins: Integrates a set of pattern and join tests   */
/*   associated with a rule into the pattern and join networks. */
/****************************************************************/
globle struct joinNode *ConstructJoins(logicalJoin,theLHS)
  int logicalJoin;
  struct lhsParseNode *theLHS;
  {
   struct joinNode *lastJoin = NULL;
   struct patternNodeHeader *lastPattern;
   int firstJoin = CLIPS_TRUE;
   int tryToReuse = CLIPS_TRUE;
   struct joinNode *listOfJoins;
   struct joinNode *oldJoin;
   int joinNumber = 1;
   int isLogical;
   struct joinNode *nandReconnect[32];
   int currentDepth = 1;
   int lastIteration = CLIPS_FALSE;
   int rhsType;
   int endDepth;
   
   /*===================================================*/
   /* Remove any test CEs from the LHS and attach their */
   /* expression to the closest preceeding non-negated  */
   /* join at the same not/and depth.                   */
   /*===================================================*/
   
   AttachTestCEsToPatternCEs(theLHS);
     
   /*=====================================================*/
   /* Process each pattern CE in the rule. At this point, */
   /* there should be no and/or/not/test CEs in the LHS.  */
   /*=====================================================*/
   
   while (theLHS != NULL)
     {
      if (theLHS->bottom == NULL) lastIteration = CLIPS_TRUE;
      
      /*==================================================*/
      /* If the pattern is the start of a new not/and CE, */
      /* then remember the join to reconnect to after the */
      /* join from the right is completed.                */
      /*==================================================*/
      
      while (theLHS->beginNandDepth > currentDepth)
        {
         nandReconnect[currentDepth-1] = lastJoin;
         currentDepth++;
        }
      
      /*============================================================*/
      /* Add the next pattern for this rule to the pattern network. */
      /*============================================================*/
        
      rhsType = theLHS->patternType->positionInArray;
      lastPattern = (*theLHS->patternType->addPatternFunction)(theLHS);
      
      /*======================================================*/
      /* Determine if the join being added is a logical join. */
      /*======================================================*/
      
      if (joinNumber == logicalJoin) isLogical = CLIPS_TRUE;
      else isLogical = CLIPS_FALSE;
      
      /*===============================================*/  
      /* Get the list of joins which could potentially */
      /* be reused in place of the join being added.   */
      /*===============================================*/  
      
      if (firstJoin == CLIPS_TRUE)
        { listOfJoins = lastPattern->entryJoin; }
      else
        { listOfJoins = lastJoin->nextLevel; }
        
      /*=======================================================*/
      /* Determine if the next join to be added can be shared. */
      /*=======================================================*/

      endDepth = theLHS->endNandDepth;
      if ((tryToReuse == CLIPS_TRUE) &&
          ((oldJoin = FindShareableJoin(listOfJoins,(VOID *) lastPattern,firstJoin,
                                        (int) theLHS->negated,isLogical,
                                        theLHS->networkTest,
                                        endDepth,currentDepth,
                                        lastIteration,nandReconnect)) != NULL) )
        {
#if DEBUGGING_FUNCTIONS
         if ((GetWatchItem("compilations") == CLIPS_TRUE) && GetPrintWhileLoading())
           { PrintCLIPS(WDIALOG,"=j"); }
#endif
         lastJoin = oldJoin;
        }
      else
        {
         tryToReuse = CLIPS_FALSE;
         lastJoin = CreateNewJoin(theLHS->networkTest,
                                  lastJoin,lastPattern,
                                  CLIPS_FALSE,(int) theLHS->negated);
         lastJoin->rhsType = rhsType;
        }

      /*==========================================================*/
      /* Create any joins from the right needed to handle not/and */
      /* CE combinations and connect them to the join network.    */
      /*==========================================================*/
      
      while (endDepth < currentDepth)
        {
         currentDepth--;
           
         if (lastJoin->nextLevel == NULL) tryToReuse = CLIPS_FALSE;
     
         if (tryToReuse)
           { 
#if DEBUGGING_FUNCTIONS
            if ((GetWatchItem("compilations") == CLIPS_TRUE) && GetPrintWhileLoading())
              { PrintCLIPS(WDIALOG,"=j"); }
#endif
            lastJoin = lastJoin->nextLevel;
           }
         else
           {
            lastJoin = CreateNewJoin(NULL,nandReconnect[currentDepth-1],
                                     lastJoin,CLIPS_TRUE,CLIPS_FALSE);
           }
        }
        
      /*=======================================*/
      /* Move on to the next join to be added. */
      /*=======================================*/

      theLHS = theLHS->bottom;
      joinNumber++;
      firstJoin = CLIPS_FALSE;
     }

   /*===================================================*/
   /* If compilations are being watched, put a carriage */
   /* return after all of the =j's and +j's             */
   /*===================================================*/
   
#if DEBUGGING_FUNCTIONS
   if ((GetWatchItem("compilations") == CLIPS_TRUE) && GetPrintWhileLoading())
     { PrintCLIPS(WDIALOG,"\n"); }
#endif

   /*=============================*/
   /* Return the last join added. */
   /*=============================*/
   
   return(lastJoin);
  }
  
/****************************************************************/
/* AttachTestCEsToPatternCEs: Attaches the expressions found in */
/*   test CEs to the closest preceeding pattern CE that is not  */
/*   negated and is at the same not/and depth.                  */
/****************************************************************/
static VOID AttachTestCEsToPatternCEs(theLHS)
  struct lhsParseNode *theLHS;
  {
   struct lhsParseNode *lastNode, *trackNode, *tempNode;
   
   /*===============================================*/
   /* Look at each pattern on the rule's LHS to see */
   /* if any test CEs should be attached to it.     */
   /*===============================================*/
   
   while (theLHS != NULL)
     {
      /*==============================================*/
      /* If the pattern is negated, then don't bother */
      /* looking for any test CEs to attach to it.    */
      /*==============================================*/
      
      if (theLHS->negated)
        { trackNode = NULL; }
      else
        {
         lastNode = theLHS;
         trackNode = theLHS->bottom;
        }
        
      /*=================================================*/
      /* Check all of the patterns following the current */
      /* pattern to check for test CEs which can be      */
      /* attached to the current pattern.                */
      /*=================================================*/
      
      while (trackNode != NULL)
        {
         /*=======================================================*/
         /* Skip over any CEs that have a higher not/and depth or */
         /* are negated since any test CEs found within these CEs */
         /* would be attached to another pattern with the same    */
         /* depth, rather than the current pattern.               */
         /*=======================================================*/
         
         if ((trackNode->beginNandDepth != theLHS->beginNandDepth) ||
             (trackNode->negated))
           {
            lastNode = trackNode;
            trackNode = trackNode->bottom;
           }
           
         /*======================================================*/
         /* Once a non-negated pattern has been encounted at the */
         /* same not/and depth as the current pattern, then stop */
         /* because any test CEs following this pattern would be */
         /* attached to it rather than the current pattern.      */
         /*======================================================*/
         
         else if (trackNode->type == PATTERN_CE)
           { trackNode = NULL; }
           
         /*==================================================*/
         /* A test CE encountered at the same not/and depth  */
         /* can be added to the network test expressions for */ 
         /* the currentpattern.                              */
         /*==================================================*/
         
         else if (trackNode->type == TEST_CE)
           {
            theLHS->networkTest = CombineExpressions(theLHS->networkTest,
                                                     trackNode->networkTest);
            trackNode->networkTest = NULL;
            tempNode = trackNode->bottom;
            trackNode->bottom = NULL;
            lastNode->bottom = tempNode;
            lastNode->endNandDepth = trackNode->endNandDepth;
            ReturnLHSParseNodes(trackNode);