factbld.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            */
   /*                                                     */
   /*                   FACT BUILD MODULE                 */
   /*******************************************************/

/*************************************************************/
/* Purpose: Given a new fact pattern, adds the pattern to    */
/*   the pattern network of the associated deftemplate. Also */
/*   contains routines for deleting a pattern from the fact  */
/*   pattern network.                                        */
/*                                                           */
/* Principal Programmer(s):                                  */
/*      Gary D. Riley                                        */
/*                                                           */
/* Contributing Programmer(s):                               */
/*                                                           */
/* Revision History:                                         */
/*                                                           */
/*************************************************************/

#define _FACTBLD_SOURCE_

#include "setup.h"

#if DEFTEMPLATE_CONSTRUCT && DEFRULE_CONSTRUCT

#include <stdio.h>
#define _CLIPS_STDIO_

#include "clipsmem.h"
#include "reteutil.h"
#include "router.h"
#include "reorder.h"
#include "factcmp.h"
#include "factmch.h"
#include "factgen.h"
#include "factmngr.h"
#include "factlhs.h"
#include "argacces.h"
#include "modulutl.h"
#include "tmpltdef.h"

#include "factbld.h"

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

#if ANSI_COMPILER
#if (! RUN_TIME) && (! BLOAD_ONLY)
   static struct factPatternNode    *FindPatternNode(struct factPatternNode *,struct lhsParseNode *,
                                                  struct factPatternNode **,int);
   static struct factPatternNode    *CreateNewPatternNode(struct lhsParseNode *,struct factPatternNode *,
                                                       struct factPatternNode *,int);
   static VOID                       ClearPatternMatches(struct factPatternNode *);
   static VOID                       DetachFactPattern(struct patternNodeHeader *);
   static struct patternNodeHeader  *PlaceFactPattern(struct lhsParseNode *);
   static struct lhsParseNode       *RemoveUnneededSlots(struct lhsParseNode *);
   static VOID                       FindAndSetDeftemplatePatternNetwork(struct factPatternNode *,struct factPatternNode *);
#endif
#else
#if (! RUN_TIME) && (! BLOAD_ONLY)
   static struct factPatternNode    *FindPatternNode();
   static struct factPatternNode    *CreateNewPatternNode();
   static VOID                       ClearPatternMatches();
   static VOID                       DetachFactPattern();
   static struct patternNodeHeader  *PlaceFactPattern();
   static struct lhsParseNode       *RemoveUnneededSlots();
   static VOID                       FindAndSetDeftemplatePatternNetwork();
#endif
#endif

/****************************************/
/* GLOBAL INTERNAL VARIABLE DEFINITIONS */
/****************************************/

   globle struct patternEntityRecord  FactInfo = { { FACT_ADDRESS,1,0,0,
                                                     PrintFactIdentifier, 
                                                     PrintFactIdentifierInLongForm,
                                                     Retract,
                                                     NULL,
                                                     GetNextFact,
                                                     IncrementFactCount,
                                                     DecrementFactCount,NULL,NULL,NULL,NULL
                                                   },
                                                   DecrementFactBasisCount,
                                                   IncrementFactBasisCount,
                                                   MatchFactFunction,
                                                   NULL
                                                 };

/***************************************/
/* LOCAL INTERNAL VARIABLE DEFINITIONS */
/***************************************/

#if (! RUN_TIME) && (! BLOAD_ONLY)
   static struct deftemplate       *CurrentDeftemplate;
#endif

/*********************************************************/
/* InitializeFactPatterns: Adds fact patterns to the set */
/*   of patterns recognized by the rule pattern parsing  */
/*   and pattern/join network integration routines.      */
/*********************************************************/
globle VOID InitializeFactPatterns()
  {
#if DEFRULE_CONSTRUCT
   InitializeFactReteFunctions();
   
#if (! RUN_TIME) && (! BLOAD_ONLY)   
   AddPatternParser("facts",0,&FactInfo,
                    FactPatternParserFind,
                    FactPatternParse,
                    NULL,PlaceFactPattern,
                    DetachFactPattern,
                    NULL,FactReplaceGetvar,
                    FactGenGetvar,FactJNVariableComparison,
                    FactGenPNConstant,FactReplaceGetfield,
                    FactGenGetfield,FactPNVariableComparison,
                    NULL,NULL,
#if INCREMENTAL_RESET
                    MarkFactPatternForIncrementalReset,
                    FactsIncrementalReset,
#else
                    NULL,NULL,
#endif
                    CreateInitialFactPattern,
#if CONSTRUCT_COMPILER
                    FactPatternNodeReference);
#else
                    NULL);
#endif

#else
   AddPatternParser("facts",0,&FactInfo,
                    NULL,NULL,NULL,NULL,NULL,NULL,NULL,
                    NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,
#if INCREMENTAL_RESET
                    MarkFactPatternForIncrementalReset,
                    FactsIncrementalReset,
#else
                    NULL,NULL,
#endif
                    NULL,NULL);  
#endif
 
#endif
  }

#if (! RUN_TIME) && (! BLOAD_ONLY)
  
/******************************************************************************/
/* PlaceFactPattern: Integrates a fact pattern into the fact pattern network. */
/******************************************************************************/
static struct patternNodeHeader *PlaceFactPattern(thePattern)
  struct lhsParseNode *thePattern;
  {
   struct lhsParseNode *tempPattern = NULL;
   struct factPatternNode *currentLevel, *lastLevel;
   struct factPatternNode *nodeBeforeMatch, *newNode;
   int endSlot, count;
   char *deftemplateName;
   
   /*======================================================================*/
   /* Get the name of the deftemplate associated with the pattern being    */
   /* added (recall that the first field of any pattern must be a symbol). */
   /*======================================================================*/
   
   deftemplateName = ValueToString(thePattern->right->bottom->value);
   
   /*=====================================================*/
   /* Remove any slot tests that test only for existance. */
   /*=====================================================*/
   
   thePattern->right = RemoveUnneededSlots(thePattern->right);
   
   /*========================================================*/
   /* If the constant test for the relation name is the only */
   /* pattern network test and there are no other network    */
   /* tests, then remove the test, but keep the node since   */
   /* there must be a link from the fact pattern network to  */
   /* the join network. Otherwise, remove the test for the   */
   /* relation name since this test has already been done    */
   /* before entering the pattern network (since each        */
   /* deftemplate has its own pattern network).              */
   /*========================================================*/
   
   if (thePattern->right->right == NULL)
     {   
      ReturnExpression(thePattern->right->networkTest);
      thePattern->right->networkTest = NULL;
     }
   else
     {
      tempPattern = thePattern->right;
      thePattern->right = thePattern->right->right;
      tempPattern->right = NULL;
      ReturnLHSParseNodes(tempPattern);
      tempPattern = NULL;
     }
     
   /*============================================================*/
   /* Get a pointer to the deftemplate data structure associated */
   /* with the pattern (use the deftemplate name extracted from  */
   /* the first field of the pattern.                            */
   /*============================================================*/

   CurrentDeftemplate = (struct deftemplate *) 
                        FindImportedConstruct("deftemplate",NULL,
                                              deftemplateName,&count,
                                              CLIPS_TRUE,NULL);
   
   /*================================================*/
   /* Initialize some pointers to indicate where the */
   /* pattern is being added to the pattern network. */
   /*================================================*/
   
   currentLevel = CurrentDeftemplate->patternNetwork;
   lastLevel = NULL;
   thePattern = thePattern->right;
   
   /*===========================================*/
   /* Loop until all fields in the pattern have */ 
   /* been added to the pattern network.        */
   /*===========================================*/
   
   while (thePattern != NULL)
     {
      /*===========================================================*/
      /* If a multifield slot is being processed, then process the */
      /* pattern nodes attached to the multifield pattern node.    */
      /*===========================================================*/
      
      if (thePattern->multifieldSlot)
        {
         tempPattern = thePattern;
         thePattern = thePattern->bottom;
        }
        
      /*============================================*/
      /* Determine if the last pattern field within */
      /* a multifield slot is being processed.      */
      /*============================================*/
      
      if ((thePattern->right == NULL) && (tempPattern != NULL)) 
        { endSlot = CLIPS_TRUE; }
      else 
        { endSlot = CLIPS_FALSE; }
        
      /*========================================*/
      /* Is there a node in the pattern network */
      /* that can be reused (shared)?           */
      /*========================================*/
      
      newNode = FindPatternNode(currentLevel,thePattern,&nodeBeforeMatch,endSlot);
   
      /*================================================*/
      /* If the pattern node cannot be shared, then add */
      /* a new pattern node to the pattern network.     */
      /*================================================*/
      
      if (newNode == NULL)
        { newNode = CreateNewPatternNode(thePattern,nodeBeforeMatch,lastLevel,endSlot); }
      
      /*===========================================================*/
      /* Move on to the next field in the new pattern to be added. */
      /*===========================================================*/

      if ((thePattern->right == NULL) && (tempPattern != NULL))
        {
         thePattern = tempPattern;
         tempPattern = NULL;
        }
        
      thePattern = thePattern->right;
      
      /*==========================================================*/
      /* If there are no more pattern nodes to be added to the    */
      /* pattern network, then mark the last pattern node added   */
      /* as a stop node (i.e. if you get to this node and the     */
      /* network test succeeds, then a pattern has been matched). */
      /*==========================================================*/
      
      if (thePattern == NULL) newNode->header.stopNode = CLIPS_TRUE;
        
      /*================================================*/
      /* Update the pointers which indicate where we're */
      /* trying to add the new pattern to the currently */
      /* existing pattern network.                      */
      /*================================================*/
      
      lastLevel = newNode;
      currentLevel = newNode->nextLevel;
     }
     
   /*==================================================*/
   /* Return the leaf node of the newly added pattern. */
   /*==================================================*/
   
   return((struct patternNodeHeader *) newNode);
  }