empserver/include/lost.h
Markus Armbruster 358aee203e Store sequence numbers more compactly
Store them and ef_type in bit-fields.

Allocate eight bits for ef_type.  Values range from 0 to EF_GAME
(currently 16), so this is plenty.

Allocate twelve bits for sequence numbers.  Sequence number mismatches
are now missed when the numbers are equal modulo 2^12.  Still
sufficiently improbable.

Common machines store the bit-fields in a 32 bit word.  There are
twelve bits left in that word for future use.  Total savings 16 bits,
which is exactly what the previous commit spent on wider uids on
common machines.
2010-01-19 08:31:10 +01:00

63 lines
2.1 KiB
C

/*
* Empire - A multi-player, client/server Internet based war game.
* Copyright (C) 1986-2009, 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 */
signed ef_type: 8;
unsigned lost_seqno: 12;
int lost_uid;
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) */
int lost_id; /* uid of lost thing (0 for sector)*/
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 lost_and_found(int, natid, natid, int, coord, coord);
extern void makelost(int, natid, int, coord, coord);
extern void makenotlost(int, natid, int, coord, coord);
extern void delete_old_lostitems(void);
#endif