Mercurial > hg > early-roguelike
view rogue4/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 |
line wrap: on
line source
/* * save and restore routines * * @(#)save.c 4.15 (Berkeley) 5/10/82 * * Rogue: Exploring the Dungeons of Doom * Copyright (C) 1980, 1981, 1982 Michael Toy, Ken Arnold and Glenn Wichman * All rights reserved. * * See the file LICENSE.TXT for full copyright and licensing information. */ #include <curses.h> #include <sys/types.h> #include <sys/stat.h> #include <errno.h> #include <string.h> #include <stdlib.h> #include <time.h> #define KERNEL #include <signal.h> #undef KERNEL #include "rogue.h" void save_file(FILE *savef); extern int rs_save_file(FILE *savef); extern int rs_restore_file(FILE *inf); typedef struct stat STAT; extern char version[], encstr[]; extern bool _endwin; STAT sbuf; /* * save_game: * Implement the "save game" command */ /* This has to be cleaned up, these goto's are annoying. */ bool save_game(void) { register FILE *savef; register int c; char buf[256]; /* * get file name */ mpos = 0; over: if (file_name[0] != '\0') { for (;;) { if (use_savedir) msg("Save game? "); else msg("save file (%s)? ", file_name); c = getchar(); mpos = 0; if (c == ESCAPE) { msg(""); return FALSE; } else if (c == 'n' || c == 'N' || c == 'y' || c == 'Y') break; else msg("please answer Y or N"); } if (c == 'y' || c == 'Y') { strcpy(buf, file_name); goto gotfile; } } if (use_savedir) { /* You can't change the savefile if you're using the system savedir, because that means you have privileges. */ msg(""); return FALSE; } do { mpos = 0; msg("file name: "); buf[0] = '\0'; if (get_str(buf, stdscr) == QUIT) { quit: msg(""); return FALSE; } mpos = 0; gotfile: /* * test to see if the file exists */ if (stat(buf, &sbuf) >= 0) { for (;;) { msg("File exists. Do you wish to overwrite it?"); mpos = 0; if ((c = readchar()) == ESCAPE) goto quit; if (c == 'y' || c == 'Y') break; else if (c == 'n' || c == 'N') goto over; else msg("Please answer Y or N"); } msg("file name: %s", buf); } strcpy(file_name, buf); if ((savef = fopen(file_name, "w")) == NULL) { msg(strerror(errno)); /* fake perror() */ if (use_savedir) return FALSE; } } while (savef == NULL); /* * write out encrpyted file (after a stat) * The fwrite is to force allocation of the buffer before the write */ save_file(savef); return TRUE; } /* * auto_save: * Automatically save a file. This is used if a HUP signal is * recieved */ void auto_save(int sig) { register FILE *savef; md_ignore_signals(); if (file_name[0] != '\0' && (savef = fopen(file_name, "w")) != NULL) save_file(savef); endwin(); exit(1); } /* * save_file: * Write the saved game on the file */ void save_file(FILE *savef) { int slines = LINES; int scols = COLS; /* * close any open score file */ if (score_file != NULL) { fclose(score_file); score_file = NULL; } move(LINES-1, 0); refresh(); fstat(md_fileno(savef), &sbuf); /* * DO NOT DELETE. This forces stdio to allocate the output buffer * so that malloc doesn't get confused on restart */ fwrite("junk", 1, 5, savef); fseek(savef, 0L, 0); encwrite(version,strlen(version)+1,savef); encwrite(&slines,sizeof(slines),savef); encwrite(&scols,sizeof(scols),savef); msg(""); rs_save_file(savef); fclose(savef); } /* * restore: * Restore a saved game from a file with elaborate checks for file * integrity from cheaters */ bool restore(char *file, char **envp) { FILE *inf; register bool syml; extern char **environ; char buf[MAXSTR]; STAT sbuf2; int slines, scols; if (strcmp(file, "-r") == 0) file = file_name; #ifdef SIGTSTP /* * If a process can be suspended, this code wouldn't work */ signal(SIGTSTP, SIG_IGN); #endif if ((inf = fopen(file, "r")) == NULL) { if (use_savedir && errno == ENOENT) { /* We're using a system savefile which doesn't exist. This isn't a fatal error, it means start a new game. */ return TRUE; } perror(file); return FALSE; } fflush(stdout); encread(buf, strlen(version) + 1, inf); if (strcmp(buf, version) != 0) { printf("Sorry, saved game is out of date.\n"); return FALSE; } stat(file, &sbuf2); fflush(stdout); syml = issymlink(file); fflush(stdout); 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 */ 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); } hw = newwin(LINES, COLS, 0, 0); keypad(stdscr,1); mpos = 0; mvprintw(0, 0, "%s: %s", file, ctime(&sbuf2.st_mtime)); if (rs_restore_file(inf) == FALSE) { endwin(); printf("Cannot restore file\n"); return(FALSE); } if ( #ifdef WIZARD !wizard && #endif md_unlink_open_file(file, inf) < 0) { endwin(); printf("Cannot unlink file\n"); return FALSE; } /* * defeat multiple restarting from the same place */ #ifdef WIZARD if (!wizard) #endif if (sbuf2.st_nlink != 1 || syml) { endwin(); printf("Cannot restore from a linked file\n"); return FALSE; } if (pstats.s_hpt <= 0) { endwin(); printf("This character is already dead.\n"); return FALSE; } #ifdef SIGTSTP signal(SIGTSTP, tstp); #endif environ = envp; strcpy(file_name, file); setup(); clearok(curscr, TRUE); touchwin(stdscr); srand(md_random_seed()); msg("file name: %s", file); status(); playit(); return 0; } /* * encwrite: * Perform an encrypted write */ void encwrite(void *starta, int size, FILE *outf) { register char *ep; register char *start = (char *) starta; ep = encstr; while (size--) { putc(*start++ ^ *ep++, outf); if (*ep == '\0') ep = encstr; } } /* * encread: * Perform an encrypted read */ int encread(void *starta, int size, FILE *inf) { register char *ep; register int read_size; register char *start = (char *) starta; if ((read_size = fread(start, 1, size, inf)) == 0) return read_size; ep = encstr; while (size--) { *start++ ^= *ep++; if (*ep == '\0') ep = encstr; } return read_size; }