Mercurial > hg > early-roguelike
view rogue4/list.c @ 83:09db0cf536af
Properly handle invalid room references in savefiles.
In all games, rs_write_room_reference() stored -1 for a nonexistent
room, but rs_read_room_reference() did not check for out-of-bounds
values, leading to pointers to rooms[-1], which sometimes caused
crashes. rs_read_room_reference() has now been modified to use NULL
instead.
Some of the games required further changes to replace NULL with the
pointer to the actual room. Others are capable of handling NULL for
objects not in any room.
author | John "Elwin" Edwards |
---|---|
date | Thu, 08 Aug 2013 12:41:35 -0700 |
parents | 9535a08ddc39 |
children | 1b73a8641b37 |
line wrap: on
line source
/* * Functions for dealing with linked lists of goodies * * @(#)list.c 4.7 (Berkeley) 12/19/81 * * Rogue: Exploring the Dungeons of Doom * Copyright (C) 1980, 1981, 1982 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 */ _detach(list, item) register THING **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 */ _attach(list, item) register THING **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 */ _free_list(ptr) register THING **ptr; { register THING *item; while (*ptr != NULL) { item = *ptr; *ptr = next(item); discard(item); } } /* * discard: * Free up an item */ discard(item) register THING *item; { total--; free((char *) item); } /* * new_item * Get a new item with a specified size */ THING * new_item() { register THING *item; if ((item = calloc(1, sizeof *item)) == NULL) msg("ran out of memory after %d items", total); else total++; item->l_next = item->l_prev = NULL; return item; }