/*
 * Revision Control Information
 *
 * $Source: /vol/opua/opua2/sis/sis-1.2/common/src/stamina/hash/RCS/install.c,v $
 * $Author: sis $
 * $Revision: 1.3 $
 * $Date: 1994/07/15 22:58:45 $
 *
 */
/* SCCSID%W% */
/************************************************************
 * install(name,order,ptr,hashtab, hash_size) --- put name  *
 *					      in hashtab.   					*
 *                                                          *
 *       (a) install uses lookup() to determine whether     *
 *           the name being installed is already present;   *
 *       (b) if so, no action taken, except return the      *
 *           pointer pointing to the exist entry            *  
 *       (c) otherwise, a completely new entry is created.  *
 *	     and return the pointer pointing the new entry  	*
 *       (d) install returns NULL if for any reason there   *
 *           is no room for a new entry.                    *
 ************************************************************/
/* Modified by June Rho  Dec. 1989 */

#include <stdio.h>
#include "hash.h"


NLIST *install(name, order, ptr, hashtab, hash_size)
char *name;
char *ptr;		/* Pointer to first structure */
int order;		/* order index of entries in hashtab */
NLIST *hashtab[];
{
	NLIST *np;	/* a pointer to nlist */
	NLIST *lookup();
	int hashval;
	char *str_save();

	if ( (np = lookup(name,hashtab,hash_size)) == NIL(NLIST) )  {	
	 						     /* not found */
	  /*np = ALLOC ( NLIST , 1 ); */
	    np = (NLIST *) malloc ((unsigned) sizeof (NLIST) );
	    if ( np == NIL(NLIST) )  {
		(void) fprintf ( stderr, "memory allocation error \n");
		return (NIL(NLIST));
	    }

	    if ((np->name = str_save(name)) == NIL(char))  {
	   	(void) fprintf(stderr, 
			"fail to copy a string, died in install.\n");
		exit(1);
	    }

	    hashval = hash(np->name, hash_size);
	    np->order_index = order;
	    np->next = hashtab[hashval];
		np->ptr = (int *) ptr;
		np->h_next = NIL(NLIST);
	    hashtab[hashval] = np;

	    return (np);/* return the pointer pointing the new entry */
	} else  {
	    return (np);/* return the pointer pointing to the exist entry */  
	}

}

NLIST 
*install_input(name, hashtab, hash_size)
char *name;
/* char *ptr;		Pointer to first structure */
/* int order;		order index of entries in hashtab */
NLIST *hashtab[];
{
	NLIST *np;	/* a pointer to nlist */
	NLIST *lookup();
	int hashval;
	char *str_save();

	if ( (np = lookup(name,hashtab,hash_size)) == NIL(NLIST) )  {	
	 						     /* not found */
	  /*np = ALLOC ( NLIST , 1 ); */
	    np = (NLIST *) malloc ((unsigned) sizeof (NLIST) );
	    if ( np == NIL(NLIST) )  {
			panic("install");
	    }

	    if ((np->name = str_save(name)) == NIL(char))  {
	   	(void) fprintf(stderr, 
			"fail to copy a string, died in install.\n");
		exit(1);
	    }

	    hashval = hash(np->name, hash_size);
/*	    np->order_index = order; */
	    np->next = hashtab[hashval];
		np->h_prev = NIL(NLIST);
		np->ptr = (int *)0;
		np->h_next = NIL(NLIST);
	    hashtab[hashval] = np;

	    return (np);/* return the pointer pointing the new entry */
	} else  {
	    return NIL(NLIST);/* return the pointer pointing to the exist entry */  
	}
}