empserver/include/lost.h
Markus Armbruster 536ef0b0a2 Add sequence numbers to game state
This oopses on output dependency violations, e.g. two threads doing a
read-modify-write without synchronization, or the one thread nesting
several read-modify-writes.  Such bugs are difficult to spot, and tend
to be abusable.  I figure we have quite a few of them.

New struct emptypedstr member seqno.  Make sure all members of unit
empobj_storage share it.  Initialize it in files: main() and
file_sct_init().  Set it in ef_blank() and new ef_set_uid() by calling
new get_seqno().  Use ef_set_uid() when copying objects: swaps(),
doland(), doship(), doplane(), dounit(), delete_old_news().  Step it
in ef_write() by calling new new_seqno().

Factor do_read() out of fillcache() to make it available for
get_seqno().
2008-05-17 22:50:30 +02:00

61 lines
2 KiB
C

/*
* Empire - A multi-player, client/server Internet based war game.
* Copyright (C) 1986-2008, Dave Pare, Jeff Bailey, Thomas Ruschak,
* Ken Stevens, Steve McClure
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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 02111-1307 USA
*
* ---
*
* See files README, COPYING and CREDITS in the root of the source
* tree for related information and legal notices. It is expected
* that future projects/authors will amend these files as needed.
*
* ---
*
* lost.h: Definitions for lost items
*
* Known contributors to this file:
* Steve McClure, 1997
*/
#ifndef LOST_H
#define LOST_H
#include <time.h>
#include "types.h"
struct loststr {
/* initial part must match struct empobj */
short ef_type;
int lost_uid;
unsigned lost_seqno;
time_t lost_timestamp; /* When it was lost */
natid lost_owner; /* Who lost it */
/* end of part matching struct empobj */
short lost_type; /* Type of thing (ship, plane, nuke, land, sector) */
short lost_id; /* ID of lost thing */
coord lost_x;
coord lost_y;
};
#define getlost(n, p) ef_read(EF_LOST, (n), (p))
#define putlost(n, p) ef_write(EF_LOST, (n), (p))
/* src/lib/subs/lostsub.c */
extern void makelost(short, natid, short, coord, coord);
extern void makenotlost(short, natid, short, coord, coord);
#endif