list.c

/*
    list.c  -  Functions for dealing with linked lists of goodies
   
    UltraRogue
    Copyright (C) 1985 Herb Chong
    All rights reserved.
    
    Based on "Advanced Rogue"
    Copyright (C) 1982, 1984, 1985 Michael Morgan, Ken Dalka and AT&T
    All rights reserved.

    Based on "Rogue: Exploring the Dungeons of Doom"
    Copyright (C) 1980, 1981 Michael Toy, Ken Arnold and Glenn Wichman
    All rights reserved.
    
    See the file LICENSE.TXT for full copyright and licensing information.
*/

#include <stdlib.h>
#include "curses.h"
#include "rogue.h"

/*
 * detach:
 *	Takes an item out of whatever linked list it might be in
 */

void
_detach(struct linked_list **list, struct linked_list *item)
{
    if (*list == item)
	*list = next(item);
    if (prev(item) != NULL) item->l_prev->l_next = next(item);
    if (next(item) != NULL) item->l_next->l_prev = prev(item);
    item->l_next = NULL;
    item->l_prev = NULL;
}

/*
 * _attach:
 *	add an item to the head of a list
 */

void
_attach(struct linked_list **list, struct linked_list *item)
{
    if (*list != NULL)
    {
	item->l_next = *list;
	(*list)->l_prev = item;
	item->l_prev = NULL;
    }
    else
    {
	item->l_next = NULL;
	item->l_prev = NULL;
    }

    *list = item;
}

/*
 * _free_list:
 *	Throw the whole blamed thing away
 */
void
_free_list(struct linked_list **ptr)
{
    register struct linked_list *item;

    while (*ptr != NULL)
    {
	item = *ptr;
	*ptr = next(item);
	discard(item);
    }
}

/*
 * discard:
 *	free up an item
 */
void
discard(struct linked_list *item)
{
    total -= 2;
    FREE(item->l_data);
    FREE(item);
}

/*
 * new_item
 *	get a new item with a specified size
 */

struct linked_list *
new_item(int size)
{
    register struct linked_list *item;

    if ((item = (struct linked_list *) new(sizeof *item)) == NULL)
	msg("Ran out of memory for header after %d items", total);
    if ((item->l_data = new(size)) == NULL)
	msg("Ran out of memory for data after %d items", total);
    item->l_next = item->l_prev = NULL;
    return item;
}

/*
 * creat_item:
 *      Create just an item structure -- don't make any contents
 */

struct linked_list *
creat_item(void)
{
    register struct linked_list *item;

    if ((item = (struct linked_list *) new(sizeof *item)) == NULL)
        msg("Ran out of memory for header after %d items", total);
    item->l_next = item->l_prev = NULL;
    return item;
}

char *
new(size_t size)
{
    register char *space = ALLOC(size);
    static char errbuf[LINELEN];

    if (space == NULL) {
	sprintf(errbuf,"Rogue ran out of memory (used = %ld, wanted = %d).",
		md_memused(), (int) size);
	fatal(errbuf);
    }
    total++;
    return space;
}