/* @(#)gen_path.c	2.1 93/05/19 */
 
/******************************************************************************/
/* function    : gen_path.c  (recursive)                                      */
/*                                                                            */
/* subsystem   : chgen                                                        */
/*                                                                            */
/* input       : path_history, path_head, target                              */
/*                                                                            */
/* output      : <none> (calls store_into_matrix)                             */
/*                                                                            */
/* returns     : void                                                         */
/*                                                                            */
/* author      : Cheng                                                        */
/*                                                                            */
/* created     : July, 1991                                                   */
/*                                                                            */
/* revisions   : 93s523: change strn(cpy/cmp) to use variable hcg_abbr_size   */
/*                                                                            */
/* description : This recursive routine traverses the cp_table, looking for   */
/*               entries matching the specified target table.  With each      */
/*               one found, check if its already in the path history.  If it  */
/*               is, it must be a cycle.  Otherwise, store the entry in the   */
/*               path matrix (that is being build), and recurse on the        */
/*               entry.                                                       */
/*                                                                            */
/******************************************************************************/


#include <stdio.h>
#include <ctype.h>
#include "chgen_define.h"
#include "chgen_externs.h"

/****************************************************************
*                                                               *
* ex : cp_table is as follows :                                 *
*      AAid:BBid                                                *
*      BBid:CCid                                                *
*      CCid:DDid                                                *
*      CCid:FFid                                                *
*      gen_path will build the following paths                  *
*            AA_BB_CC_DD (for path_length = 3 )                 *
*            AA_BB_CC_FF (for path_length = 3 )                 *
*                      .                                        *
*                      .                                        *
*                      .                                        *
*            AA_BB_CC    (for path_length = 2 )                 *
*            AA_CC_DD    (for path_length = 2 )                 *
*                      .                                        *
*                      .                                        *
*                      .                                        *
*                                                               *
****************************************************************/

void gen_path ( path_history, path_head, target )
char path_history[];
char path_head[];
char target[];
{
	static char rcsid[] = "";
        char child_abbrev[ABBREV_NAME_LENGTH] ,
             parent_abbrev[ABBREV_NAME_LENGTH] ,
	     temp_abbrev[ABBREV_NAME_LENGTH];

        struct rr_type *curr_ptr ;
        int i , j , x , y , cycle ;

        curr_ptr = cp_table ;
        while (curr_ptr != NULL)
        {

                strncpy_null(child_abbrev,curr_ptr->firstid,hcg_abbr_size);
                strncpy_null(parent_abbrev,curr_ptr->secondid,hcg_abbr_size);

                if(strcmp(target,child_abbrev)==0)
                {
                        i = 0;
                        cycle = 0;
                        while(path_history[i]!='\0')
                        {
                                if(strncmp(path_history+i,parent_abbrev,
					   hcg_abbr_size) == 0)
                                {
                                        cycle = 1;
                                        break;
                                }
                                i += hcg_abbr_size;
                        }
                        if(!cycle)
                        {
			  strncpy_null(path_history+i,parent_abbrev,
				       hcg_abbr_size);

                                /* get TTchildindex, x and TTparentindex, y */
                                TXindex = encoding(path_head);
                                x = TINDEX[TXindex].TTindex ;

			   strncpy_null(temp_abbrev, curr_ptr->secondid, 
					hcg_abbr_size);

                                TXindex = encoding(temp_abbrev);
                                y = TINDEX[TXindex].TTindex ;

                                store_into_matrix(x, y, i/hcg_abbr_size, 
						  path_history);


                                gen_path(path_history,path_head,parent_abbrev);
                                path_history[i] = '\0' ;
                        }
                }
                curr_ptr = curr_ptr->next_ptr ;
        }

      return;

}