view srogue/save.c @ 280:70aa5808c782

Fix potential segfaults at restore related to ctime(). In some games, restore() passes the result of ctime() to mvprintw() or some other variadic message-formatting function. If ctime() has not been declared properly, its return type is inferred to be int instead of char *. This does not cause a warning because the compiler does not know the correct type of variadic arguments. On platforms where ints and pointers are not the same size, this can, probably depending on alignment, result in a segfault that is not easy to trace. Including time.h fixes the problem. Some games manually declared ctime() and avoided the bug. These declarations have also been replaced with the include.
author John "Elwin" Edwards
date Fri, 15 Sep 2017 20:51:10 -0400
parents d3968e9cb98d
children e52a8a7ad4c5
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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <signal.h>
#include <time.h>
#include <errno.h>
#if !defined(_WIN32)
#include <unistd.h>
#endif
#include "rogue.h"
#include "rogue.ext"

EXTCHAR version[];

bool dosave(void);
void save_file(FILE *savef);

typedef struct stat STAT;
STAT sbuf;

/*
 * ignore:
 *	Ignore ALL signals possible
 */
void
ignore(void)
{
	md_ignoreallsignals();
}

/*
 * save_game:
 *	Save the current game
 */
bool
save_game(void)
{
	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:
 *	Save the game.  UID/GID no longer get reset here.
 */
bool
dosave(void)
{
	FILE *savef;

	ignore();
	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
 */
void
save_file(FILE *savef)
{
	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

	encwrite(version,strlen(version)+1,savef);
	encwrite(&slines,sizeof(slines),savef);
	encwrite(&scols,sizeof(scols),savef);
	msg("");
	rs_save_file(savef);
	fclose(savef);
	md_onsignal_exit();
	wclear(cw);
	draw(cw);
}

/*
 * restore:
 *	Restore a saved game from a file
 */
bool
restore(char *file, char **envp)
{
	register int 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
	FILE *inf;
	char buf[LINLEN];
	STAT sbuf2;
	int slines, scols;

	if ((inf = fopen(file, "r")) == NULL) {
		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;
	}

	stat(file, &sbuf2);

	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
	 */

#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);
        keypad(cw, 1);

	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__)
	fclose(inf);
#endif
	if (!wizard)
	{
		if (md_unlink_open_file(file, inf) < 0)
		{
			endwin();
			printf("Cannot unlink file\n");
			return FALSE;
		}
	}

	if (him->s_hpt <= 0) {
		endwin();
		printf("This character is already dead.\n");
		return FALSE;
	}

	environ = envp;

	strcpy(file_name, file);
	setup();
	restscr(cw);
	md_srandom(md_random_seed());
	playit();
}