[unix-history] / usr / src / games / trek / dumpgame.c

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#ifndef lint
static char sccsid[] = "@(#)dumpgame.c	4.3 (Berkeley) %G%";
#endif not lint

# include	"trek.h"

/***  THIS CONSTANT MUST CHANGE AS THE DATA SPACES CHANGE ***/
# define	VERSION		2

struct dump
{
	char	*area;
	int	count;
};


struct dump	Dump_template[] =
{
	(char *)&Ship,		sizeof (Ship),
	(char *)&Now,		sizeof (Now),
	(char *)&Param,		sizeof (Param),
	(char *)&Etc,		sizeof (Etc),
	(char *)&Game,		sizeof (Game),
	(char *)Sect,		sizeof (Sect),
	(char *)Quad,		sizeof (Quad),
	(char *)&Move,		sizeof (Move),
	(char *)Event,		sizeof (Event),
	0
};

/*
**  DUMP GAME
**
**	This routine dumps the game onto the file "trek.dump".  The
**	first two bytes of the file are a version number, which
**	reflects whether this image may be used.  Obviously, it must
**	change as the size, content, or order of the data structures
**	output change.
*/

dumpgame()
{
	int			version;
	register int		fd;
	register struct dump	*d;
	register int		i;

	if ((fd = creat("trek.dump", 0644)) < 0)
		return (printf("cannot dump\n"));
	version = VERSION;
	write(fd, &version, sizeof version);

	/* output the main data areas */
	for (d = Dump_template; d->area; d++)
	{
		write(fd, &d->area, sizeof d->area);
		i = d->count;
		write(fd, d->area, i);
	}

	close(fd);
}


/*
**  RESTORE GAME
**
**	The game is restored from the file "trek.dump".  In order for
**	this to succeed, the file must exist and be readable, must
**	have the correct version number, and must have all the appro-
**	priate data areas.
**
**	Return value is zero for success, one for failure.
*/

restartgame()
{
	register int	fd;
	int		version;

	if ((fd = open("trek.dump", 0)) < 0 ||
	    read(fd, &version, sizeof version) != sizeof version ||
	    version != VERSION ||
	    readdump(fd))
	{
		printf("cannot restart\n");
		close(fd);
		return (1);
	}

	close(fd);
	return (0);
}


/*
**  READ DUMP
**
**	This is the business end of restartgame().  It reads in the
**	areas.
**
**	Returns zero for success, one for failure.
*/

readdump(fd1)
int	fd1;
{
	register int		fd;
	register struct dump	*d;
	register int		i;
	int			junk;

	fd = fd1;

	for (d = Dump_template; d->area; d++)
	{
		if (read(fd, &junk, sizeof junk) != (sizeof junk))
			return (1);
		if ((char *)junk != d->area)
			return (1);
		i = d->count;
		if (read(fd, d->area, i) != i)
			return (1);
	}

	/* make quite certain we are at EOF */
	return (read(fd, &junk, 1));
}
Commit	Line	Data
9758240b KM	1	/*
	2	* Copyright (c) 1980 Regents of the University of California.
	3	* All rights reserved. The Berkeley software License Agreement
	4	* specifies the terms and conditions for redistribution.
	5	*/
	6
1184f029	7	#ifndef lint
9758240b	8	static char sccsid[] = "@(#)dumpgame.c 4.3 (Berkeley) %G%";
1184f029 KM	9	#endif not lint
	10
	11	# include "trek.h"
	12
	13	/* THIS CONSTANT MUST CHANGE AS THE DATA SPACES CHANGE */
401a08c7	14	# define VERSION 2
1184f029 KM	15
	16	struct dump
	17	{
	18	char *area;
	19	int count;
	20	};
	21
401a08c7 KL	22
401a08c7 KL	23	struct dump Dump_template[] =
1184f029	24	{
401a08c7 KL	25	(char *)&Ship, sizeof (Ship),
	26	(char *)&Now, sizeof (Now),
	27	(char *)&Param, sizeof (Param),
	28	(char *)&Etc, sizeof (Etc),
	29	(char *)&Game, sizeof (Game),
	30	(char *)Sect, sizeof (Sect),
	31	(char *)Quad, sizeof (Quad),
	32	(char *)&Move, sizeof (Move),
	33	(char *)Event, sizeof (Event),
1184f029 KM	34	0
	35	};
	36
	37	/*
	38	** DUMP GAME
	39	**
	40	** This routine dumps the game onto the file "trek.dump". The
	41	** first two bytes of the file are a version number, which
	42	** reflects whether this image may be used. Obviously, it must
	43	** change as the size, content, or order of the data structures
	44	** output change.
	45	*/
	46
	47	dumpgame()
	48	{
	49	int version;
	50	register int fd;
	51	register struct dump *d;
	52	register int i;
	53
	54	if ((fd = creat("trek.dump", 0644)) < 0)
	55	return (printf("cannot dump\n"));
	56	version = VERSION;
	57	write(fd, &version, sizeof version);
	58
	59	/* output the main data areas */
	60	for (d = Dump_template; d->area; d++)
	61	{
	62	write(fd, &d->area, sizeof d->area);
	63	i = d->count;
	64	write(fd, d->area, i);
	65	}
	66
	67	close(fd);
	68	}
	69
	70
	71	/*
	72	** RESTORE GAME
	73	**
	74	** The game is restored from the file "trek.dump". In order for
	75	** this to succeed, the file must exist and be readable, must
	76	** have the correct version number, and must have all the appro-
	77	** priate data areas.
	78	**
	79	** Return value is zero for success, one for failure.
	80	*/
	81
	82	restartgame()
	83	{
	84	register int fd;
	85	int version;
	86
	87	if ((fd = open("trek.dump", 0)) < 0 \|\|
	88	read(fd, &version, sizeof version) != sizeof version \|\|
	89	version != VERSION \|\|
	90	readdump(fd))
	91	{
	92	printf("cannot restart\n");
	93	close(fd);
	94	return (1);
	95	}
	96
	97	close(fd);
98	return (0);
99	}
100
101
102	/*
103	** READ DUMP
104	**
105	** This is the business end of restartgame(). It reads in the
106	** areas.
107	**
108	** Returns zero for success, one for failure.
109	*/
110
111	readdump(fd1)
112	int fd1;
113	{
114	register int fd;
115	register struct dump *d;
116	register int i;
117	int junk;
118
119	fd = fd1;
120
121	for (d = Dump_template; d->area; d++)
122	{
401a08c7	123	if (read(fd, &junk, sizeof junk) != (sizeof junk))
1184f029	124	return (1);
401a08c7	125	if ((char *)junk != d->area)
1184f029 KM	126	return (1);
	127	i = d->count;
	128	if (read(fd, d->area, i) != i)
	129	return (1);
	130	}
	131
	132	/* make quite certain we are at EOF */
	133	return (read(fd, &junk, 1));
	134	}