view srogue/save.c @ 81:0e212d46b68f

rogue4: don't put savefile metadata into the savefile. The save_file() function in save.c stored the savefile's device number, inode number, creation time, and modification time in the file. The restore() function read them back, and apparently used to compare them to protect against cheaters. Unfortunately, the types and sizes of these numbers differ from system to system, which ruins the Roguelike Restoration Project's fine portability work. So they have been removed from the savefile. This BREAKS SAVEFILE COMPATIBILITY, but old files can be converted by excising the chunk starting at offset 0x22 with length sizeof(ino_t) + sizeof(dev_t) + 2 * sizeof(time_t). That's 0x14 on i686 and 0x20 on x86_64, at least with current versions of Linux and glibc.
author John "Elwin" Edwards
date Mon, 05 Aug 2013 20:49:41 -0700
parents 3aa87373c908
children f11eeafc6568
line wrap: on
line source

/*
 * save and restore routines
 *
 * @(#)save.c	9.0	(rdk)	 7/17/84
 *
 * Super-Rogue
 * Copyright (C) 1984 Robert D. Kindelberger
 * All rights reserved.
 *
 * Based on "Rogue: Exploring the Dungeons of Doom"
 * Copyright (C) 1980, 1981 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 <string.h>
#include <unistd.h>
#include <ctype.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <signal.h>
#include <errno.h>
#include "rogue.h"
#include "rogue.ext"

#ifdef BSD
#define srand48(seed)	srandom(seed)
#endif

EXTCHAR version[];
EXTCHAR *ctime();

typedef struct stat STAT;
STAT sbuf;

/*
 * ignore:
 *	Ignore ALL signals possible
 */
ignore()
{
	int i;

	for (i = 0; i < NSIG; i++)
		signal(i, SIG_IGN);
}

/*
 * save_game:
 *	Save the current game
 */
save_game()
{
	reg FILE *savef;
	reg int c;
	char buf[LINLEN];

	mpos = 0;
	if (file_name[0] != '\0') {
		if (use_savedir)
			msg("Save game? (y/n) ");
		else
			msg("Save file (%s)? ", file_name);
		do {
			c = wgetch(cw);
			if(c == ESCAPE) {
				msg("");
				return FALSE;
			}
		} while (c != 'n' && c != 'y');
		mpos = 0;
		if (c == 'y')
			goto gotfile;
	}
	if (use_savedir) {
		msg("");
		return FALSE;
	}
	msg("File name: ");
	mpos = 0;
	buf[0] = '\0';
	if (get_str(buf, cw) == QUIT) {
		msg("");
		return FALSE;
	}
	msg("");
	strcpy(file_name, buf);
gotfile:
	c = dosave();		/* try to save this game */
	if (c == FALSE)
		msg("Could not save game to file %s", file_name);
	return c;
}

/*
 * auto_save:
 *	Automatically save a game
 */
void
auto_save(int a)
{
	dosave();		/* save this game */
	byebye(1);		/* so long for now */
}

/*
 * game_err:
 *	When an error occurs. Set error flag and save game.
 */
void
game_err(int a)
{
	int ok;

	ok = dosave();			/* try to save this game */
	clear();
	refresh();
	endwin();

	printf("\nInternal error !!!\n\nYour game was ");
	if (ok)
		printf("saved.");
	else
		printf("NOT saveable.");

	fflush(stdout);

#ifdef SIGIOT
	signal(SIGIOT, SIG_DFL);	/* allow core dump signal */
#endif

	abort();			/* cause core dump */
	byebye(3);
}

/*
 * dosave:
 *	Set UID back to user and save the game
 */
dosave()
{
	FILE *savef;

	ignore();
	if (!use_savedir)
	{
		setuid(playuid);
		setgid(playgid);
	}
	umask(022);

	if (file_name[0] != '\0') {
		if ((savef = fopen(file_name,"w")) != NULL)
		{
			save_file(savef);
			return TRUE;
		}
	}
	return FALSE;
}

/*
 * save_file:
 *	Do the actual save of this game to a file
 */
save_file(savef)
FILE *savef;
{
	reg int fnum;
	int slines = LINES;
	int scols = COLS;

#ifdef __DJGPP__                      /* st_ino w/ DJGPP under WinXP broken */
        _djstat_flags |= _STAT_INODE; /* so turn off computing it for now   */
#endif

	/*
	 * force allocation of the buffer now so that inodes, etc
	 * can be checked when restoring saved games.
	 */
	fnum = fileno(savef);
	fstat(fnum, &sbuf);
	write(fnum, "RDK", 4);
	lseek(fnum, 0L, 0);
	encwrite(version,strlen(version)+1,savef);
	encwrite(&sbuf.st_ino,sizeof(sbuf.st_ino),savef);
	encwrite(&sbuf.st_dev,sizeof(sbuf.st_dev),savef);
	encwrite(&sbuf.st_ctime,sizeof(sbuf.st_ctime),savef);
	encwrite(&sbuf.st_mtime,sizeof(sbuf.st_mtime),savef);
	encwrite(&slines,sizeof(slines),savef);
	encwrite(&scols,sizeof(scols),savef);
	msg("");
	rs_save_file(savef);
	close(fnum);
	signal(SIGINT, byebye);
	signal(SIGQUIT, byebye);
	wclear(cw);
	draw(cw);
}

/*
 * restore:
 *	Restore a saved game from a file
 */
restore(file, envp)
char *file, **envp;
{
	register inf, pid;
	int ret_status;
#ifndef _AIX
	extern char **environ;
#endif
#ifdef __DJGPP__                      /* st_ino w/ DJGPP under WinXP broken */
        _djstat_flags |= _STAT_INODE; /* so turn off computing it for now   */
#endif
	char buf[LINLEN];
	STAT sbuf2;
	int slines, scols;

	if ((inf = open(file, O_RDONLY)) < 0) {
		if (use_savedir && errno == ENOENT)
			return TRUE;
		else {
			printf("Cannot read save game %s\n",file);
			return FALSE;
		}
	}

	encread(buf, strlen(version) + 1, inf);

	if (strcmp(buf, version) != 0) {
		printf("Sorry, saved game version is out of date.\n");
		return FALSE;
	}

	fstat(inf, &sbuf2);

	encread(&sbuf.st_ino,sizeof(sbuf.st_ino), inf);
	encread(&sbuf.st_dev,sizeof(sbuf.st_dev), inf);
	encread(&sbuf.st_ctime,sizeof(sbuf.st_ctime), inf);
	encread(&sbuf.st_mtime,sizeof(sbuf.st_mtime), inf);
	encread(&slines,sizeof(slines),inf);
	encread(&scols,sizeof(scols),inf);

	/*
	 * we do not close the file so that we will have a hold of the
	 * inode for as long as possible
	 */

	if (!wizard)
	{
		if(sbuf2.st_ino!=sbuf.st_ino || sbuf2.st_dev!=sbuf.st_dev) {
			printf("Sorry, saved game is not in the same file.\n");
			return FALSE;
		}
	}

#ifdef __INTERIX
	setenv("TERM","interix");
#endif

	initscr();

	if (slines > LINES)
	{
		endwin();
		printf("Sorry, original game was played on a screen with %d lines.\n",slines);
		printf("Current screen only has %d lines. Unable to restore game\n",LINES);
		return(FALSE);
	}

	if (scols > COLS)
	{
		endwin();
		printf("Sorry, original game was played on a screen with %d columns.\n", scols);
		printf("Current screen only has %d columns. Unable to restore game\n",COLS);
		return(FALSE);
	}

	cw = newwin(LINES, COLS, 0, 0);
	mw = newwin(LINES, COLS, 0, 0);
	hw = newwin(LINES, COLS, 0, 0);

	mpos = 0;
	mvwprintw(cw, 0, 0, "%s: %s", file, ctime(&sbuf2.st_mtime));

	/* defeat multiple restarting from the same place */

	if (!wizard)
	{
		if (sbuf2.st_nlink != 1)
		{
                        endwin();
			printf("Cannot restore from a linked file\n");
			return FALSE;
		}
	}

	if (rs_restore_file(inf) == FALSE)
	{
		endwin();
		printf("Cannot restore file\n");
		return(FALSE);
	}

#if defined(__CYGWIN__) || defined(__DJGPP__)
	close(inf);
#endif
	if (!wizard)
	{
#ifndef __DJGPP__
			endwin();
			if (!use_savedir)
			{
				while((pid = fork()) < 0)
					sleep(1);

				/* set id to unlink file */
				if(pid == 0)
				{
					setuid(playuid);
					setgid(playgid);
					unlink(file);
					exit(0);
				}
				/* wait for unlink to finish */
				else
				{
					while(wait(&ret_status) != pid)
						continue;
					if (ret_status < 0)
					{
						printf("Cannot unlink file\n");
						return FALSE;
					}
				}
			}
			else
			{
				/* Don't drop privileges, they're needed
				 * for the unlink. */
				if (unlink(file) < 0)
				{
					printf("Cannot unlink file\n");
					return FALSE;
				}
			}
#else
		if (unlink(file) < 0)
		{
			printf("Cannot unlink file\n");
			return FALSE;
		}
#endif

	}

	environ = envp;

	strcpy(file_name, file);
	setup();
	restscr(cw);
	srand48(getpid());
	playit();
}