[Emacs-diffs] Changes to emacs/lib-src/update-game-score.c

[Colin Walters]

Index: emacs/lib-src/update-game-score.c
diff -c emacs/lib-src/update-game-score.c:1.4 
emacs/lib-src/update-game-score.c:1.5
*** emacs/lib-src/update-game-score.c:1.4       Sun Apr  7 00:46:03 2002
--- emacs/lib-src/update-game-score.c   Wed Apr 10 15:10:23 2002
***************
*** 19,26 ****
  Boston, MA 02111-1307, USA.  */
  
  /* This program is allows a game to securely and atomically update a
!    score file.  It should be installed setgid, owned by an appropriate
!    group like `games'.
  
     Created 2002/03/22, by Colin Walters <address@hidden>
  */
--- 19,30 ----
  Boston, MA 02111-1307, USA.  */
  
  /* This program is allows a game to securely and atomically update a
!    score file.  It should be installed setuid, owned by an appropriate
!    user like `games'.
! 
!    Alternatively, it can be compiled without HAVE_SHARED_GAME_DIR
!    defined, and in that case it will store scores in the user's home
!    directory (it should NOT be setuid).
  
     Created 2002/03/22, by Colin Walters <address@hidden>
  */
***************
*** 36,50 ****
  #include <pwd.h>
  #include <ctype.h>
  #include <fcntl.h>
  #include <sys/stat.h>
  #include <config.h>
  
  #define MAX_ATTEMPTS 5
  
  #ifdef HAVE_SHARED_GAME_DIR
  #define SCORE_FILE_PREFIX HAVE_SHARED_GAME_DIR
  #else
! #define SCORE_FILE_PREFIX "$HOME"
  #endif
  
  int
--- 40,61 ----
  #include <pwd.h>
  #include <ctype.h>
  #include <fcntl.h>
+ #include <stdarg.h>
  #include <sys/stat.h>
  #include <config.h>
  
  #define MAX_ATTEMPTS 5
+ #define MAX_SCORES 200
+ #define MAX_DATA_LEN 1024
  
  #ifdef HAVE_SHARED_GAME_DIR
  #define SCORE_FILE_PREFIX HAVE_SHARED_GAME_DIR
  #else
! #define SCORE_FILE_PREFIX "~/.emacs.d/games"
! #endif
! 
! #if !defined (__GNUC__) || __GNUC__ < 2
! #define __attribute__(x) 
  #endif
  
  int
***************
*** 90,96 ****
      {
        int count = 1;
        int uid = (int) getuid();
!       while (uid /= 10)
        count++;
        name = malloc(count+1);
        sprintf(name, "%d", uid);
--- 101,108 ----
      {
        int count = 1;
        int uid = (int) getuid();
!       int tuid = uid;
!       while (tuid /= 10)
        count++;
        name = malloc(count+1);
        sprintf(name, "%d", uid);
***************
*** 107,112 ****
--- 119,136 ----
    return buf->pw_dir;
  }
  
+ void lose(const char *msg, ...)
+      __attribute__ ((format (printf,1,0), noreturn));
+ 
+ void lose(const char *msg, ...)
+ {
+     va_list ap;
+     va_start(ap, msg);
+     vfprintf(stderr, msg, ap);
+     va_end(ap);
+     exit(1);
+ }
+ 
  int
  main(int argc, char **argv)
  {
***************
*** 115,121 ****
    char *scorefile, *prefix;
    struct stat buf;
    struct score_entry *scores;
!   int newscore, scorecount, reverse = 0, max = -1;
    char *newdata;
    struct passwd *passwdbuf;
  
--- 139,145 ----
    char *scorefile, *prefix;
    struct stat buf;
    struct score_entry *scores;
!   int newscore, scorecount, reverse = 0, max = MAX_SCORES;
    char *newdata;
    struct passwd *passwdbuf;
  
***************
*** 132,137 ****
--- 156,163 ----
        break;
        case 'm':
        max = atoi(optarg);
+       if (max > MAX_SCORES)
+         max = MAX_SCORES;
        break;
        default:
        usage(1);
***************
*** 142,203 ****
  
    passwdbuf = getpwuid(getuid());
  
!   if (!strcmp(SCORE_FILE_PREFIX, "$HOME"))
      {
!       prefix = get_home_dir(passwdbuf);
!       if (!prefix)
!       {
!         fprintf(stderr, "Unable to determine home directory\n");
!         exit(1);
!       }
      }
    else
!     prefix = SCORE_FILE_PREFIX;
!   
!   scorefile = malloc(strlen(prefix) + strlen(argv[optind]) + 1);
    if (!scorefile)
!     {
!       fprintf(stderr, "Couldn't create score file name: %s\n",
!             strerror(errno));
!       goto fail;
!     }
    strcpy(scorefile, prefix);
    strcat(scorefile, argv[optind]);
    newscore = atoi(argv[optind+1]);
    newdata = argv[optind+2];
    
    if (stat(scorefile, &buf) < 0)
!     {
!       fprintf(stderr, "Failed to access scores file \"%s\": %s\n",
!             scorefile, strerror(errno));
!       goto fail;
!     }
    if (lock_file(scorefile, &lockstate) < 0)
!     {
!       fprintf(stderr, "Failed to lock scores file \"%s\": %s\n",
!             scorefile, strerror(errno));
!       goto fail;
!     }
    if (read_scores(scorefile, &scores, &scorecount) < 0)
      {
!       fprintf(stderr, "Failed to read scores file \"%s\": %s\n",
!             scorefile, strerror(errno));
!       goto fail_unlock;
      }
    push_score(&scores, &scorecount, newscore, get_user_id(passwdbuf), newdata);
    sort_scores(scores, scorecount, reverse);
    if (write_scores(scorefile, scores, scorecount) < 0)
      {
!       fprintf(stderr, "Failed to write scores file \"%s\": %s\n",
!             scorefile, strerror(errno));
!       goto fail_unlock;
      }
    unlock_file(scorefile, lockstate);
    exit(0);
-  fail_unlock:
-   unlock_file(scorefile, lockstate);
-  fail:
-   exit(1);
  }
  
  int
--- 168,232 ----
  
    passwdbuf = getpwuid(getuid());
  
!   if (!strncmp(SCORE_FILE_PREFIX, "~", 1))
      {
!       char *homedir = get_home_dir(passwdbuf);
!       if (!homedir)
!       lose("Unable to determine home directory\n");
!       prefix = malloc(strlen(homedir) + strlen(SCORE_FILE_PREFIX) + 1);
!       strcpy(prefix, homedir);
!       /* Skip over the '~'. */
!       strcat(prefix, SCORE_FILE_PREFIX+1);
      }
    else
!     prefix = strdup(SCORE_FILE_PREFIX);
! 
!   if (!prefix)
!     lose("Couldn't create score file name: %s\n", strerror(errno));
! 
!   scorefile = malloc(strlen(prefix) + strlen(argv[optind]) + 2);
    if (!scorefile)
!     lose("Couldn't create score file name: %s\n", strerror(errno));
! 
    strcpy(scorefile, prefix);
+   free(prefix);
+   strcat(scorefile, "/");
    strcat(scorefile, argv[optind]);
    newscore = atoi(argv[optind+1]);
    newdata = argv[optind+2];
+   if (strlen(newdata) > MAX_DATA_LEN)
+     newdata[MAX_DATA_LEN] = '\0';
    
    if (stat(scorefile, &buf) < 0)
!     lose("Failed to access scores file \"%s\": %s\n", scorefile,
!        strerror(errno));
    if (lock_file(scorefile, &lockstate) < 0)
!       lose("Failed to lock scores file \"%s\": %s\n",
!          scorefile, strerror(errno));
    if (read_scores(scorefile, &scores, &scorecount) < 0)
      {
!       unlock_file(scorefile, lockstate);
!       lose("Failed to read scores file \"%s\": %s\n", scorefile,
!          strerror(errno));
      }
    push_score(&scores, &scorecount, newscore, get_user_id(passwdbuf), newdata);
+   /* Limit the number of scores.  If we're using reverse sorting, then
+      we should increment the beginning of the array, to skip over the
+      *smallest* scores.  Otherwise, we just decrement the number of
+      scores, since the smallest will be at the end. */
+   if (scorecount > MAX_SCORES)
+     scorecount -= (scorecount - MAX_SCORES);
+     if (reverse)
+       scores += (scorecount - MAX_SCORES);
    sort_scores(scores, scorecount, reverse);
    if (write_scores(scorefile, scores, scorecount) < 0)
      {
!       unlock_file(scorefile, lockstate);
!       lose("Failed to write scores file \"%s\": %s\n", scorefile,
!          strerror(errno));
      }
    unlock_file(scorefile, lockstate);
    exit(0);
  }
  
  int
***************
*** 236,246 ****
      while ((c = getc(f)) != EOF
           && !isspace(c))
        {
!       if (unameread == unamelen)
!         {
!           if (!(username = realloc(username, unamelen *= 2)))
!             return -1;
!         }
        username[unameread] = c;
        unameread++;
        }
--- 265,273 ----
      while ((c = getc(f)) != EOF
           && !isspace(c))
        {
!       if (unameread >= unamelen-1)
!         if (!(username = realloc(username, unamelen *= 2)))
!           return -1;
        username[unameread] = c;
        unameread++;
        }
***************
*** 366,372 ****
--- 393,403 ----
      return -1;
    strcpy(tempfile, filename);
    strcat(tempfile, ".tempXXXXXX");
+ #ifdef HAVE_MKSTEMP
    if (mkstemp(tempfile) < 0
+ #else
+   if (mktemp(tempfile) != tempfile
+ #endif
        || !(f = fopen(tempfile, "w")))
      return -1;
    for (i = 0; i < count; i++)
***************
*** 374,433 ****
                scores[i].data) < 0)
        return -1;
    fclose(f);
!   rename(tempfile, filename);
!   return 0;
! }
! 
! #if 0
! int
! lock_file(const char *filename, void **state)
! {
!   struct flock lock;
!   int *istate;
!   int fd, attempts = 0, ret = 0;
!   lock.l_type = F_WRLCK;
!   lock.l_whence = SEEK_SET;
!   lock.l_start = 0;
!   lock.l_len = 0;
!   istate = malloc(sizeof(int));
!   if (!istate)
      return -1;
!   if ((fd = open(filename, O_RDWR, 0600)) < 0)
      return -1;
!   *istate = fd;
!  trylock:
!   attempts++;
!   if ((ret = fcntl(fd, F_GETLK, &lock)) == -1)
!     {
!       if (ret == EACCES || ret == EAGAIN)
!       if (attempts > MAX_ATTEMPTS)
!         exit(1);
!       else
!         {
!           sleep((rand() % 3)+1);
!           goto trylock;
!         }
!       else
!       ret = 0 ;
!     }
!   else
!     ret = 0;
!   *state = istate;
!   return ret;
! }
! 
! int
! unlock_file(const char *filename, void *state)
! {
!   int fd, ret;
!   fd = *((int *) state);
!   free(state);
!   ret = close(fd);
!   return ret;
  }
  
- #else
- 
  int
  lock_file(const char *filename, void **state)
  {
--- 405,417 ----
                scores[i].data) < 0)
        return -1;
    fclose(f);
!   if (rename(tempfile, filename) < 0)
      return -1;
!   if (chmod(filename, 0644) < 0)
      return -1;
!   return 0;
  }
  
  int
  lock_file(const char *filename, void **state)
  {
***************
*** 450,457 ****
             lose some scores. */
          if (attempts > MAX_ATTEMPTS)
            unlink(lockpath);
!         else
!           sleep((rand() % 2)+1);
          goto trylock;
        }
        else
--- 434,440 ----
             lose some scores. */
          if (attempts > MAX_ATTEMPTS)
            unlink(lockpath);
!         sleep((rand() % 2)+1);
          goto trylock;
        }
        else
***************
*** 471,475 ****
    errno = saved_errno;
    return ret;
  }
- 
- #endif
--- 454,456 ----