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dis6502/ref.c
2003-09-15 21:49:25 +00:00

108 lines
2.3 KiB
C

/*
* dis6502 by Robert Bond, Udi Finkelstein, and Eric Smith
*
* $Id: ref.c,v 1.5 2003/09/15 21:49:25 eric Exp $
* Copyright 2001-2003 Eric Smith <eric@brouhaha.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation. Note that permission is
* not granted to redistribute this program under the terms of any
* other version of the General Public License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA
*/
#include <stdint.h>
#include <stdio.h>
#include "dis.h"
#define HTSIZE 0x1000 /* Power of 2 */
#define HTMASK (HTSIZE-1)
struct hashslot {
addr_t addr; /* The key */
struct ref_chain *ref; /* Who references it */
char *name; /* The symbolic name (if it has one) */
};
struct hashslot hashtbl[HTSIZE]; /* the hash table */
struct hashslot *hash (addr_t loc, int allocate)
{
int probes;
register struct hashslot *hp;
hp = &hashtbl[loc & HTMASK];
probes = 0;
while (probes< HTSIZE) {
if (hp->addr == loc)
return(hp);
if (hp->name == NULL && hp->ref == NULL) {
if (allocate) {
hp->addr = loc;
return(hp);
} else {
return(NULL);
}
}
hp++;
if (hp == &hashtbl[HTSIZE])
hp = &hashtbl[0];
probes++;
}
crash("Hash table full");
/*NOTREACHED*/
}
void save_ref (addr_t refer, addr_t refee)
{
struct ref_chain *rc;
struct hashslot *hp;
rc = (struct ref_chain *)emalloc(sizeof(*rc));
rc->who = refer;
hp = hash(refee, 1);
rc->next = hp->ref;
hp->ref = rc;
}
void save_name (addr_t loc, char *name)
{
struct hashslot *hp;
hp = hash(loc, 1);
hp->name = name;
}
struct ref_chain *get_ref(addr_t loc)
{
struct hashslot *hp;
hp = hash(loc, 0);
if (!hp)
return(NULL);
return(hp->ref);
}
char * get_name(addr_t loc)
{
struct hashslot *hp;
hp = hash(loc, 0);
if (!hp)
return(NULL);
return(hp->name);
}