/*-
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * The game adventure was originally written in Fortran by Will Crowther
 * and Don Woods.  It was later translated to C and enhanced by Jim
 * Gillogly.  This code is derived from software contributed to Berkeley
 * by Jim Gillogly at The Rand Corporation.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * @(#)save.c	8.1 (Berkeley) 5/31/93
 * $FreeBSD: src/games/adventure/save.c,v 1.8 1999/12/19 00:21:51 billf Exp $
 * $DragonFly: src/games/adventure/save.c,v 1.3 2007/04/18 18:32:12 swildner Exp $
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include "hdr.h"

struct savestruct
{
	void *address;
	int width;
};

struct savestruct save_array[] =
{
	{&abbnum,        sizeof(abbnum)},
	{&attack,        sizeof(attack)},
	{&blklin,        sizeof(blklin)},
	{&bonus,         sizeof(bonus)},
	{&chloc,         sizeof(chloc)},
	{&chloc2,        sizeof(chloc2)},
	{&clock1,        sizeof(clock1)},
	{&clock2,        sizeof(clock2)},
	{&closed,        sizeof(closed)},
	{&closng,        sizeof(closng)},
	{&daltlc,        sizeof(daltlc)},
	{&demo,          sizeof(demo)},
	{&detail,        sizeof(detail)},
	{&dflag,         sizeof(dflag)},
	{&dkill,         sizeof(dkill)},
	{&dtotal,        sizeof(dtotal)},
	{&foobar,        sizeof(foobar)},
	{&gaveup,        sizeof(gaveup)},
	{&holdng,        sizeof(holdng)},
	{&iwest,         sizeof(iwest)},
	{&k,             sizeof(k)},
	{&k2,            sizeof(k2)},
	{&knfloc,        sizeof(knfloc)},
	{&kq,            sizeof(kq)},
	{&latncy,        sizeof(latncy)},
	{&limit,         sizeof(limit)},
	{&lmwarn,        sizeof(lmwarn)},
	{&loc,           sizeof(loc)},
	{&maxdie,        sizeof(maxdie)},
	{&mxscor,        sizeof(mxscor)},
	{&newloc,        sizeof(newloc)},
	{&numdie,        sizeof(numdie)},
	{&obj,           sizeof(obj)},
	{&oldlc2,        sizeof(oldlc2)},
	{&oldloc,        sizeof(oldloc)},
	{&panic,         sizeof(panic)},
	{&saved,         sizeof(saved)},
	{&savet,         sizeof(savet)},
	{&scorng,        sizeof(scorng)},
	{&spk,           sizeof(spk)},
	{&stick,         sizeof(stick)},
	{&tally,         sizeof(tally)},
	{&tally2,        sizeof(tally2)},
	{&tkk,           sizeof(tkk)},
	{&turns,         sizeof(turns)},
	{&verb,          sizeof(verb)},
	{&wd1,           sizeof(wd1)},
	{&wd2,           sizeof(wd2)},
	{&wzdark,        sizeof(wzdark)},
	{&yea,           sizeof(yea)},
	{atloc,          sizeof(atloc)},
	{dloc,           sizeof(dloc)},
	{dseen,          sizeof(dseen)},
	{fixed,          sizeof(fixed)},
	{hinted,         sizeof(hinted)},
	{linkx,           sizeof(linkx)},
	{odloc,          sizeof(odloc)},
	{place,          sizeof(place)},
	{prop,           sizeof(prop)},
	{tk,             sizeof(tk)},

	{NULL,   0}
};

/* Two passes on data: first to get checksum, second */
/* to output the data using checksum to start random #s */
int
save(const char *outfile)
{
	FILE *out;
	struct savestruct *p;
	char *s;
	long sum;
	int i;

	crc_start();
	for (p = save_array; p->address != NULL; p++)
		sum = crc(p->address, p->width);
	srandom((int) sum);

	if ((out = fopen(outfile, "wb")) == NULL)
	{
	    fprintf(stderr,
		"Hmm.  The name \"%s\" appears to be magically blocked.\n",
		outfile);
	    return 1;
	}

	fwrite(&sum, sizeof(sum), 1, out);      /* Here's the random() key */
	for (p = save_array; p->address != NULL; p++)
	{
		for (s = p->address, i = 0; i < p->width; i++, s++)
			*s = (*s ^ random()) & 0xFF;      /* Lightly encrypt */
		fwrite(p->address, p->width, 1, out);
	}
	fclose(out);
	return 0;
}

int
restore(const char *infile)
{
	FILE *in;
	struct savestruct *p;
	char *s;
	long sum, cksum;
	int i;

	cksum = 0;
	if ((in = fopen(infile, "rb")) == NULL)
	{
	    fprintf(stderr,
		"Hmm.  The file \"%s\" appears to be magically blocked.\n",
		infile);
	    return 1;
	}

	fread(&sum, sizeof(sum), 1, in);        /* Get the seed */
	srandom((int) sum);
	for (p = save_array; p->address != NULL; p++)
	{
		fread(p->address, p->width, 1, in);
		for (s = p->address, i = 0; i < p->width; i++, s++)
			*s = (*s ^ random()) & 0xFF;  /* Lightly decrypt */
	}
	fclose(in);

	crc_start();                            /* See if she cheated */
	for (p = save_array; p->address != NULL; p++)
		cksum = crc(p->address, p->width);
	if (sum != cksum)                       /* Tsk tsk */
	    return 2;                           /* Altered the file */
	/* We successfully restored, so this really was a save file */
	/* Get rid of the file, but don't bother checking that we did */
	return 0;
}
